How I Learned to Twist

Any good head gasket requires that it get properly torqued. I am going to outline some of the tips that go with making a head gasket work properly and last as long as possible.

I believe it goes with out saying that cleanliness is an absolute must. When you read my article on head gaskets you will note that I emphasize having clean mating surfaces so that the gasket takes a hold of the metal. Using acetone and alcohol will ensure that it has that edge the gasket material can get a hold on to.

You will need before you move on:

• a good square of glass about 8 inches,
• 800 grit wet-dry sand paper,
• some light oil
• small wire brush
• can of spray carburetor cleaner

Find a good stable flat surface to place the glass onto, put a section of wet-dry sand paper down with the grit side up on the glass. Put a teaspoon of oil onto the paper. Find the acorn nuts that hold the head on. Place the flat side down on the paper and using circular strokes, polish the end of the nut until it appears flat. This re-establishes a new flat surface for proper torque. Next do the same thing with the washers on both sides. This will ensure a level torque to the washers, and seal the head from leaks around the stud. Any grit under the washer will cause a water leak.  Last, take the carb cleaner and the small brush to clean the threads on the nuts to remove any residual grit or grime.

Install the washers with the curved side up. The thin washers go on top of the engine lifting bracket. Next is to oil the studs with enough oil to coat the threads. I hand install the nuts until they make contact with the washers. Set the torque wrench to 25 lbs and following the factory torque sequence of cross torquing and working your way out from the center, set the value. Turn your torque wrench to 40 lbs and repeat the process. My last setting is to the factory value for your particular engine, rechecking twice to make sure they are all the correct value. Last step is to clean up any residual oil left behind.

I can’t imagine having to do a head gasket or work on an Alfa, or any other car for that matter with out a good “quality” torque wrench. There are several types that I will discuss the good and bad of each one. I have my preferences as you probably do too, so just understand this is my opinion and not to cast stones at any ones preference. The several types are: slipper, click type, beam, electronic, programmable electronic and mechatronic/angle.

Slipper torque wrench – this wrench will slip when the proper torque is reached and will not go any further.

Slip style torque wrench

Deflecting beam torque wrench- This is usually what a novice will get because of cost and how often it will be used. This is just a simple pointer indicator on a dial to give you a close approximate to the desired value. I have seen better ones with a gauge that you can adjust so that it comes to zero before you use it. How wide the gap is between the increments would be better for a more accurate result, compared to a gauge that is narrower between the marks.

Deflector beam torque wrench

The click type is the most popular as it releases tension when the device reaches the dialed in torque value and you hear or feel the “click”. There is also the ratcheting head so it can be used like a ratchet without having to remove the tool for going forwards as well as backwards. Usually the torque is dialed in by twisting the base of the wrench to the ft/lbs that are desired in half/lb increments. Then the tool is applied and torque is introduced. As the bolt or nut reaches the value, the torque wrench lets go with a click and no more torque should be applied.

Dial indicator on a click type torque wrench

These come in various torque ranges from in/lbs up to 250 or more ft/lbs.There is now the electronic version that has an electronic indicator number face and an audible tone when the torque is reached. The strain on the transducer measures the torque.

Craftsman Electronic Torque Wrench

The programmable torque wrench works the same way but with a preset limit.

In addition to this is the “angle” torque wrench. When the torque is set, then an angle gauge is installed and the torque wrench is swung to a set factory limit in degrees. The Alfa cylinder head on a V6 is torqued to 80 lbs and then angle torqued. This device usually sits between the bolt or nut and the torque wrench.

Lastly is the mechatronic torque wrench which is a “click” type, with a transmitter to a remote box that reads output on a numerical face.

Mechatronic torque wrench

Always remove the torque from the wrench before storing and in a box that protects it. This is a precision tool that if properly it will last a very long time with repeatable accurate results. If you buy a high quality torque wrench like Snap-on you can send it back to the factory for re-calibration.

I personally have a Snap on beam torque wrench with a rotating dial so I can reset my zero point and a movable indicator for setting the limit. When the dial indicator for torque moves it reaches the movable limit indicator letting me know I am there. It is simple and accurate. The end of the torque wrench is open for inserting a longer arm so less pushing force is applied over the longer distance.

This is a picture of what the SnapOn Torque wrench dial looks like.

Reopen the Alfa Romeo Musuem!

All you have to do is follow this link and sign the petition. We need 100,000 signatures with 97,000 more to go to make this happen. ALFA ROMEO MUSEUM

Currently the Alfa Romeo Museum is closed indefinitely. Check out the videos on the website to get an insight as to the historical treasure that awaits you. To lose this would be a travesty to the testimony to all the hard working people that created a marque that is now 100 years old.

Also check out my story here on the museum.

Now go vote!!

How High Can You Get on an Alfa Engine?

Your Alfa smoking? Feeling not to peppy? Sluggish? I might suggest you need to take it to the doctor for an examination of its innard workings to see if it needs a compression test.

This is most likely one of those Alfa Romeo 101 Basics type of test that you think everyone should know, but they don’t. This test was taught to me by a very skilled and knowledgeable Alfa Romeo mechanic when I first started to wrench on Alfas.

Why a compression test? First if you are buying a car, it will give you an idea as to the condition of the motor and a bargaining position. If the owner gives you the compression then your  that much further ahead. It is also a way to diagnose your own engine over time for issues that might come up.

Let me guide you through a simple but effective compression test so you know you are getting the right numbers.

Most Alfa’s have a compression ratio of 9.0:1 (nine to one) Compression can go up from there with higher compression ratio pistons and subsequently so does the gauge readings. What I have learned over the years is that most compression readings will be around 180 lbs per cylinder. The allowance is 10% between cylinders. If you get a large variance, then we have to dig deeper to understand what is exactly going on.

You are going to need a good quality compression guage that can give you repeatable results and last a long time. My recommendation is to get the a compression guage that has a screw in fixture to the spark plug hole. That way you can work by yourself and have two hands free to run the tests. You will also need a good device for squirting oil which I will explain later on. If you happen to have a leak down tester then you are even in better shape for diagnosing compression problems.

First you need a warm engine, so that the rings are properly sealed. Take some compressed air with a small nozzle and put a rag over the top of the spark plugs and blow out any loose dirt that has accumulated around the base of the plug. Why? Because dirt falls in to the hole. Want to guess the result of that? It falls on the face of the valve and creates a compression leak. The rag is to keep the debris from going everywhere.

Remove the wire from the + voltage side of the coil so you don’t get shocked or cause a fire when you turn the engine over. I just remove the center coil wire and drop it down to the frame so it sparks to ground.
Next take your spark plug wrench and give the plugs a 1/4 turn to loosen and then re-tighten. Do this for all 4 or 6 plugs depending upon your engine. Turn the engine for a few seconds. What you have done is to break loose any carbon inside the combustion chamber that has accumulated around the base of the spark plug. This breaks it loose and removes it out through the exhaust.

Next remove the plugs and lay them out in sequencial order (#1, #2 etc). Look at the color of the plugs and see if they are a greyish brown color. If they are you are running a good mixture. If they are dark it could be from being to rich to burning oil. If they are white, the mixture is to lean or the plug is to hot. Computer controlled injection will tend to be on the lean side and the plugs will be lighter than a carbureted car.

Next, put the compression guage in the #1 plug hole and secure tightly. Next, go inside the car, push the gas pedal to the floor to open the throats wide open and turn the engine over 10 revolutions. Hopefully you can remember to count. Here is why you open the throttles wide open. This allows the cylinder to load up with air as if it was driving down the road. If you should do it with the throttles closed you will get a significantly lower compression reading.

Note the compression and write it down. Do this for all 4 cylinders. If you have a healthy engine the compression should be within 10 lbs. of each other. Be sure you release the pressure in the gauge before moving it to the next cylinder.  A normal Alfa with 9:1 compression will show about 180 psi on the gauge  Higher compression pistons, a higher reading. If you should get a cylinder that is low, go back and rerun the test. It might change.

Compression gauge showing low compression on a Alfa cylinder

Here is what you do if you come across low compression readings. First have you rerun the compression test to verify it wasn’t a fluke or that carbon hasn’t fallen on the valve face? You might want to use a compressed air nozzle and blow out the cylinder to see if carbon is the culprit. If it still comes up the same, now you squirt oil into the cylinder. About 3 good squirts or a tablespoon of normal weight oil you use should suffice. The oil will seal the top rings to increase your compression. Re run the compression test and notice the results. If it stays the same, we try another test. If the compression goes up, you have weak or bad rings. A weak cylinder(s) will be low, usually under 130 psi. 

Lets say the compression doesn’t go up, then chance are you have a burnt valve. If you think this is the case, bring the piston up to TDC with the valves closed and push in some compressed air. Listen through the intake and the tail pipe to hear leaking air to tell you which valve it might be.

A leak down tester is a comparative tool. It measures the incoming air from the source (50-100 psi) and what leaks out from the cylinder. It should be under 10%. If you have leakage, open the oil cap and listen to see if it hisses in the crankcase (rings). If you hear hissing air in the intake or out the tail pipe your valves are leaking.

Alfa Romeo Giulietta Sprint Speciale – Designed by the Wind

Once in a while something crosses your path that catches your attention. This article did just that and with permissions I have linked to the article for your reading pleasure. The author is Mike Gulett whose blog site is about Iso/Bizzarini cars. I know you will enjoy reading about these amazing cars as much as I have.

by Mike –

Giacomo Arosio has written for My Car Quest before and this past Saturday I met him for the first time in person in Bresso, Italy at the Iso celebration.

I had asked him before the trip if I could publish this article on the Alfa Romeo Giulietta Sprint Speciale and here it is.

Follow to the rest of the article here…

What is the best Penetrating Oil?

I would bet you have some of these penetrating oils kicking around your shops or tool boxes like I do. I have a gallon of WD-40 that has to be about 25-30 years old now in the back of my work shop. Of course there is the obligatory can of PB Blaster in my roll about tool tray for those quick jobs. Now that I have read about the choices like you will, I am sure you will find that not only is there a  cheaper solution that works. This article is all over the internet, so it must have some validity.

A study done by Machinist’s Workshop magazine in their April 2007 issue looked at different penetrating oils to see which one did the best job of removing a rusted bolt by measuring the pounds of torque required to loosen the bolt once treated. If the study was scientifically accurate, it turns out a home brew works best!
Here’s the summary of the test results:

Penetrating oil ….. Average load

None …………………. 516 pounds
WD-40 ………………. 238 pounds
PB Blaster ………….. 214 pounds
Liquid Wrench …… 127 pounds
Kano Kroil …………. 106 pounds
ATF-Acetone mix….53 pounds (50-50 mix)

(ATF is automatic transmission fluid)
Acetone will dissolve paint! The fumes are not to be breathed in an enclosed area.

If you mix it up fresh, put it in a bottle for storage. Just know that the two fluids have different densities and will separate out. Just shake the bottle before use.

The test used some machined up test devices, ran them in a salt bath and a high moisture content bath so they would rust up good and tight. Then using a press, broke them apart using the aforementioned solutions and recorded the results.

WD-40 is great stuff and been around forever. You can visit their website by clicking on the WD-40 link to learn why it was created and a million uses. I used it on latex wall paint to remove creative art projects from my kids with Crayons.

PB Blaster is a great product but it pales in comparison to the acetone/transmission oil combination. I like this product more than I do Liquid Wrench. I use this on just about everything that has to come apart or going back together that doesn’t need anti-seize compound.

Liquid Wrench is another one of those products that has been around since…well forever. I didn’t know it was a better product than PB Blaster looking at the results above. The company also makes “GUNK” engine cleaner. Love the product but the smell! Don’t you think that Liquid Wrench has the smell of diesel in it?

Kano Kroil I have heard of, but have no experience with the product. Looking at the results the product appears to really do its work. In reading up on the product from a couple of sources, people swear by it, including the US Navy who uses it by the 55 gallon drum. You “cannot” buy this at any parts store, but only direct from the company on their website. One web source says to check your local gun store as it is great for lubricating. I copied this from a website:

The Oil That Creeps, loosens frozen metal parts.  A scientific discovery reduces the surface tension so that this amazing solvent creeps into openings as small as one millionth of an inch.  Wherever there is corrosion due to heat, salt water, chemical action or weathering Kroil will loosen metal joints in a few minutes time, saving labor, equipment and temper.  It dissolves gum, dried grease and oil, removes rust and carbon deposits without attacking the metal and provides proper lubrication.  Resists wetting so prevents rust.

I hope this “primer” on penetrating fluids has crept in to loosen up your ideas of what you might want to carry on your shelves for loosening tight nuts and bolts. We love tight nuts but we also want to be able to get them loose somewhere down the road. Just remember, “It only takes one loose nut to scatter a car of a 1000 pieces all over the road.”

Don’t Blow a Head Gasket

On the heels of the 0-ring topic, here comes the head gasket. This topic is like art, it has to be done a certain way and everyone has a spin on what works for them. Let me say up front that after doing a lot of head gaskets, my success rate is pretty high. What I do is just plain simple “cleanliness” when doing a head gasket. This is written so that it covers not only 1300/1600, but also 1750/2000 engines.

The most obvious fact about doing a head gasket is to get the head off and determine why you are doing all of this labor. Most times it is because the head gasket failed due to leaking out the sides on a cold start. Anti-freeze or oil will run down the block in streaks until the block heats up enough to seal the surfaces. Usually this is caused by the head not being properly torqued, re-torqued or rechecked. The head gets a tad loose and the sealing surface gets wide and the fluids find the path of least resistance. One morning you come out and there is a puddle of anti-freeze or oil under your car you haven’t noticed before that is probably bigger than usual. You take your index finger, touch it, inspect it and “wallah!” its fluid.

Take the head off. I won’t go into a long discussion on how to remove the head as there are several books and threads on the Alfa Bulletin Board.  Now here is where it gets crazy. What if the head doesn’t want to come off? Everything is loose, including the two bolts under the head. You have popped it loose just a hair to break the gasket seal, yet it won’t go more than an inch. Ok. What gives? It is stud corrosion! Yes, the insidious stud corrosion that comes from gunk and rust building up on the studs inside the head passages to where it is so thick you can’t get the head to move. Solution: Lots of spray carburetor cleaner, and PB Blaster soaking down around the stud holes. After letting this soak in for a day applying liberal amounts, the crud should soften up enough that you can begin to move the head. It won’t come easy, but it will lift off. Just be sure you go up and down, and it will come off. Worst case for me was to get a 2×4 and lever it in between the block and head to push up on the cylinder head. I have heard of one case that the head wouldn’t come off, the engine had to be pulled and replaced. Yes, it was that bad.

Install some liner holders so that the liners don’t move and break the seal on the bottom of the liner and block. Trust me, you don’t want the liners to move! You can use some large washers, metal tubing, more washers on top and the “acorn” nut to hold it all in place. Just make the nut tight (about 10-15 ft lbs) to hold it in place.

Now that you have the head off, look at the head gasket and inspect the o-rings. Are they nice and round? Deformed? Hard or soft? If they are soft, most likely they are Viton or some material like it. Look at the sealing surfaces and see if you can find where the leak was coming from. If it was a blown head gasket due to a weak spot or over heating, see if you can spot it. Usually it is a dark spot between the cylinders or out towards a water jacket hole.
Peel the gasket off and toss. Sometimes it just lifts off leaving very little behind .Other times it will be a pulling affair to remove it, leaving lots of material to clean up.

When you do get the head off, check it for flatness using a machined straight edge and feeler guages. When you lay the straight edge on the head you should see no light under the metal. Measure and you should get zero (0) to .002 thousands clearance. Any more and you will have to mill the head for a skim cut.

Something you will notice when you get the head gasket off is the corrosion around the stud holes. This is normal electrolysis and milling the head down to remove it only wastes life of the head. Welding is expensive, so save your dollars. As long as the corrosion doesn’t effect any of the sealing surfaces, just leave it. What you do want to look for is cracks in the aluminum. If you want, take it to a machine shop and have it dye penetrated for cracks. Cracks can occur generally between the water jacket and a valve seat. This can be repaired with welding and a new valve seat.

Note the arrow showing a crack in the cylinder head.

Ok, here is your list of tools and supplies you will need:

1. Carburetor cleaner or acetone
2. Gasket scraper – wide face
3. Pipe cleaners – large
4. 800 grit wet/dry sand paper
5. Clean rags and/or paper towels

Install the pipe cleaners into the oil passages. Leave about a 1/3 sticking out of the hole and bend over so it doesn’t slide down in the passage. This will help you from getting head gasket material down in the oil passage! Put some rags or paper towels in the chain galley to keep junk from falling down into the oil sump. Want to guess where that will wind up? (see the end of the article *)

Soak the mating surface of the head and block with the carburetor cleaner/acetone. Allow for adequate ventilation. Let sit until the gasket material turns soft or continue to soak with fluid until it does. You do not want to force the material to come loose as we are dealing with aluminum. Any scratches or deep marks is not a good thing on a sealing surface. Gently use the gasket scraper to push the gasket material off the head and block. Do not push down hard, if you are pushing hard you need to soak more. Most of the gasket material will just come right off if you have worked it correctly leaving behind a brownish or grey colored residue.

On the block you can use an Exacto knife, single edge razor blade or something sharp to clean around the locating studs for the head and head gasket. Do not use it anywhere else! This will let you get the minute stuff that you can’t get with the gasket scraper.

Now that you have all of the gasket material off, you are now going to spray the carburetor cleaner on the block and cylinder head to make it wet. Using the 800 grit paper, you will “lightly polish” off the rest of the gasket material until you have a nice clean shiny surface for the new gasket to seal to. Remember this is what the gasket will stick to, cleaner surface the better the seal. Do not overly push as you can leave depressions or wave marks in the surface of the soft aluminum. If you have a small wood block to wrap the paper around that would be a good way to make sure it is level when you polish.

If you sent the head out for repairs, most likely it will come back with a skim cut which should be very fine in appearance or hot tanked leaving a nice clean head you don’t have to mess with until your ready to install the head gasket. Shown below is a before and after shot of what your head should look like.

Using the acetone or carburetor cleaner, use some tissues to do a final wipe down of all the surfaces taking off all oil residue. Remove the pipe cleaners and rags in the chain galley.

Before I go any further, I only put sealant on the back part of the head gasket as per my note below. There are some who will spray gasket sealer on both sides of the head gasket to insure sealing. I have seen Permatex copper sealant used. If you use a gasket that has

no sealant properties on it, then this is great stuff. A Reinz or Victor gasket will usually have a sealant applied to the head gasket. Your choice…use it or not.

Put the head gasket in place, making sure it lies flat on the block and in place with the locating studs. Install the o-rings in to their respective holes (see previous article on o-rings). Slide the head onto the studs and lower gently until the head is sitting on the locating studs or all the way down. The rest is by the book.

While the head has been soaking in cleaner to loosen the head gasket material, I get a sheet of the 800 grit paper, some water, a flat surface like a glass pane and sand both sides of the washers till they are flat again. I also do the same to the bottom of the acorn nuts so they are flat as well. This insures a even torque on the stud, washer face and a clean sealing surface so there are no leaks of coolant around the studs.

Some like to use fresh oil as per the factory book to lubricate the acorn nuts and studs when installing. I prefer to use aluminum anti-seize compound as it just makes it easier to come off next time. Oil can turn to carbon and become sticky or hard, making removal difficult.

Torque is essential and in the correct order. I usually start with 25 ft/lbs, go to 40 ft/lbs, and then torque to final ft/lbs. This way I get a gentle crush on the gasket and o-rings.

In closing there are two more points that are important to remember. Some of the new gaskets do not have sealer around the back of the block crank case ventilation holes in the head. You must use some high temperature gasket sealer on these surfaces or area.
The 2nd point is that you re-torque the head after the engine has fully warmed up to temperature. Back off a 1/4 turn and torque to final value again. I let it sit over night and check torque,  but I don’t back off the nut. If you have no movement your good to go. After 500 miles re-torque again by checking. Some say to back off a 1/4 turn and then reset. I just check them for proper torque.

I am hoping I covered all the important points and why I have good success with head gaskets not leaking. If I forgot a step or you have a hint/trick that works for you, let me know and I will drop it into a the article.

* it winds up in the oil pump screen, in the oil pump, oil filter and who knows where else*

Oh Oh O-Rings!

Now you want to get into something controversial, it has to do with those o-rings that sit in side the head gasket to seal the oil passages to the cam camshafts. As long as I can remember (getting shorter as I get older), these o-rings have leaked. It wasn’t a question of “will it leak?” It was more like “how many miles before it does start leaking?”

The factory had a great idea, but the execution was poor in my opinion. The material was supposed to work,  as described in the description of the material properties, but it was short term. Given enough time of heat/cold cycles, the o-ring would take a set, the sealing properties of the head gasket would fail, and being that the oil passage is a high pressure area, eventually the oil would find a way out. This “weeping” on a cold engine, would leave a fresh oil track down the side of the block until the aluminum would heat up and reseal. The worst case I have seen is when the o-ring would fail and oil would shoot out between the block and head.

When I was working at Rockwell International, we had a SEM (scanning electron microscope). I asked one of the techs to do me a favor and look at the o-rings up close. What we found out is that the o-rings were made of Buna N rubber. Buna N rubber under heat and pressure will take a set. In other words it will lose its elasticity. The rubber was broken down in to chunks under high magnification. Ever notice how hard they are when you take them out of a head gasket? It is because they were squashed and baked to the thickness of the head gasket. Sometimes the o-ring even bent in on itself because it had no where to go when it was compressed. This had the effect of closing off some portion of the oil passage.

Wikipedia has this to say about Viton o-rings, “Viton o-rings are the only known solution to the pervasive use of Buna-N seals in many popular BMW automobile engine variable timing units, known as VANOS. In the VANOS, the Buna-N o-ring deteriorate while the Viton fluorocarbon o-rings have similar functional characteristics to Buna-N, but with much higher temperature and chemical resistance characteristics.” This is why most use Viton o-rings in post factory head gasket repairs so to minimize the leaks.

The best thing you can do is to get Viton o-rings. Viton is a Dupont trade name for  Viton is a synthetic rubber compound that is impervious to oil, gasoline and heat. it is what is called a “fluoroelastomers” made with Florine and other compounds. So, what does this mean to you? It means that theoretically you could reuse the o-rings next time you replace the head gasket. I do not recommend that you do. The o-ring will not take a set, it will remain pliable, and it will seal the oil passage.

CHOICES AND DESCRIPTOR

Now you have a choice, two to be exact. you can get a “square cut” or the traditional “round” o-ring. What matters the most is the vertical thickness and width of the  o-ring itself, and the external dimensions so it fits securely in the hole in the head gasket. If the o-ring is to thick it will compress and expand inward blocking the oil passage.

If you want to get into the engineering side of o-rings, you can read up on the Parker O-ring web site. This is a .pdf file that is very lengthy. Here is what the front page of the manual says, “Since its initial release in 1957, the Parker O-Ring Handbook has become a fixture on the reference shelves of engineers worldwide. This book contains extensive information about the properties of basic sealing elastomers, as well as examples of typical o-ring applications, fundamentals of static and dynamic seal design and o-ring failure modes. It also provides an overview of international sizes and standards, and compatibility data for fluids, gases and solids.”

I have a Parker O-ring bag here with some o-rings in it for an Alfa Romeo head gasket. On the outside of the bag it says that the Parker size is 5-583 with an inside diameter of .251″ This translates in another table to # 5-583 inside diameter.251″, Tolerance +/- .005,  width .074″, tolerance +/-.003  # 5-583  inside diameter 6.38 mm, Tolerance +/-  0.13 mm,  Width 1.88 mm Tolerance +/-.08 mm.

The material number I can’t source. The bag says it is “V247-75″ I suspect that is a descriptor of the material number.

FAILURE OF O-RINGS

Here is what Parker says as to why o-rings fail:

Probably the most common cause of O-ring failure is compression set. An effective O-ring seal requires a continuous “seal line” between the sealed surfaces. The establishment of
this “seal line” is a function of gland design and seal crosssection which determines the correct amount of squeeze (compression) on the O-ring to maintain seal integrity without excessive deformation of the seal element.

In general, Compression Set is caused by one or more of the following conditions:
1. Selection of O-ring material with inherently poor compression
set properties.
2. Improper gland design.
3. Excessive temperature developed causing the O-ring to harden
and lose its elastic properties. (High temperatures may be
caused by system fluids, external environmental factors, or
frictional heat build-up.)
4. Volume swell of the O-ring due to system fluid.
5. Excessive squeeze due to over tightening of adjustable glands.
6. Incomplete curing (vulcanization) of O-ring material during
production.
7. Introduction of fluid incompatible with O-ring material. (Parker.com)

 (Parker.com)

SOLUTIONS

You can continue to use the o-rings that come with the head gasket in the head gasket kits. However, you really don’t know what is being used for the o-ring material. It could most likely be Buna N rubber like the factory. Then you get the same results as before.

There are several “solutions” to this problem depending upon who you buy your head gasket from. 

• Viton o-rings (just a few pennies more per o-ring)
• Dowel pins and Viton o-rings
• Retaining metal rings that insert into the center of the o-ring to prevent deformation
• Sealant on the o-ring (I personally don’t recommend)

When buying the head gasket ask your parts supplier what 0-rings are being used. Most will tell you they are using Viton and will come in a separate baggie.

Best solution is to buy the correct thickness of o-ring so when it is compressed it doesn’t deform by protruding, doesn’t take a heat or compression set (proper material choice) and will last the life of the engine. Cost? Pennies per o-ring and it doesn’t cut the oil supply to the head.

The dowel pin approach has been around since the 70′s. A dowel pin is inserted into the oil passage, the o-ring is then slipped around the pin after the head gasket is installed. The intent is to force the oil through the dowel pin, isolating the o-ring from the oil, and preventing o-ring deformation cutting off the oil supply to the head. The only problems I see using this approach is oil restriction of the oil passage to a pin being inserted into the path way that is smaller than the factory orifice. Also I have seen the pins slip down into the block! Then how do you get them out?

  
This is a rolled dowel pin, notice how it curves in on itself. Here is a picture of the pin installed in the block. (AlfaBB)

There are two types of dowel pins…rolled and split. Most dowel pins I have seen are the split (down the middle). The other is a “rolled” dowel pin so that it curves around over itself.  Measuring the dowel pin that I have here that is the rolled type, the inside measurement is 2.7 mm. The factory opening in the block is 5 mm. The split dowel pin could be even smaller. By inserting a pin into the oil passage your effectively cutting off about 50% of the oil supply to the cams. Does it work? Yes. Is it a good idea? Yes. Does it cut your oil supply to your cams? Yes. I will leave it up to you to decide if you are going to use the dowel pins or not.

Another solution is to buy a kit that has small metal rings that are custom sized, to slip inside of the o-ring. The head gasket is put on the block, the o-ring is inserted into the head   gasket, and the metal ring is put into the o-ring. The intent here is to keep the o-ring from being compressed to where it deforms to protrude over the oil passage and to retain its shape to seal the head gasket. The trick here is to find the right thickness of o-ring so it meets the criteria of sealing, but not overly thick. Does it work? Yes. Is it a good idea? Yes. Does it cut the supply of oil? No.

Putting sealant on the o-ring? Is it a good idea? Yes, in theory. Does it work? Yes. Does it cut the supply of oil? No. Does it offer more protection over the proper o-ring? Maybe. My opinion is to just insert the proper sized o-ring of the correct material.

 (Alfabb)

Here is the head gasket in place with the pin and o-ring. Note the black sealant on the head gasket. This melts at temperature when your get your engine hot and forms a seal. If both sides of the block are clean, this will seal properly.

Any questions or comments please post them and I will answer them to the best of my knowledge. These posts are just my opinion and open to comments.