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Tackling the oil leak from the front rhs of the head soon. Seems to be a common problem. In Pat Braden’s book he mentions a mod to insert roll pins into the oilways in the block to locate the O rings. Is this considered to be a good idea.? Will it not restrict oil getting to the head? If a good idea where can I get them as none of the usual GB sources seem to list them.
 

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By 75 or 76 Alfa was putting in roll pins at the factory. The main purpose is to hold the o-ring in place. Modern o-rings are better than in Pat's time and don't deform or "figure 8" as much, but the roll pins, or Norman Racing brass ring kit, is a good idea, yes. Restricting oil to the cam bearings is a good thing, not bad. Way more oil goes up there than needed, so if you restrict a bit it keeps more oil at the crankshaft.
Andrew
 

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I second what Andrew said...

Also, I would recommend Viton for all the o-rings and Viton seals for all that you intend to replace. I got all mine from Alfa Romeo parts from Spruell Motorsport Alfa but don't see them listed now. You may want to contact them but I am sure that there are other sources for Viton o-rings and seals.

Mark
 

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Don't use roll pins or anything with a groove. I have some o-rings here that molded themselves into the groove and eventually split. Smooth tubes are required. A friend used short pieces of 3/16 brake line, which involved drilling the head and block to fit.
 

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See post #4. These are ALL I use. Superior to roll or split pins as they cannot disappear into the oil gallery. They work on all Alfa blocks, 750-1300 through 2L. You can modify by internally threading and install restrictors if needed. In my opinion, from my experience, these work best. I've posted comments and applications as well as use in other threads over the years.
 
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The rollpins Alfa used were finely rolled with a smooth exterior. not hardware store roll pins with a rough split down the side.
You can solder up the Norman ones and redrill smaller to restrict oil flow to the cam bearings.
Andrew
 

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+1 on John Norman "roll pins"
 

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Does the Jon Norman kit require counterboring the head or block for the little step in the tube OD, or does that go in the middle of the o-ring?
 

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no special machining or boring...for 2L anyway. Put in pin, then o-ring.
 

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No. The little step is thinner than the compressed head gasket and only prevents the pin from disappearing into the block oil galleries. As I'm unable to find my original discussion on these from years ago, I'll do it again.
 

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You are correct, the shoulder hits home on the block deck, and the O-ring fits over the larger step to hold its shape.
 

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First the issue. Initially, 101-1600 era and earlier, there were no connectors between head and block, and this was often the result.
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Racing TransAm GTA's we made connectors of aluminum that looked much like Norman's.
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Often the "O" rings were blown up into the head plugging cam oil feed holes. This resulted in "blue" cam journals ("Oh! That one got hot!") and damaged heads so we made up connectors to support the "O" rings.
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The positive side effect was no more oil leaks between head and block through the head gasket.
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This is a kit. It's cheap and works perfectly with Reinz and other head gaskets. With some blocks, the hole in the block deck is a trifle tight, usually 1300's, 101 and 750's, 105's and newer are more uniform, but regardless, we made up a drift to correctly install the connectors in tight deck holes.
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The inside diameter of the hole exactly matches the OD of the connector small end, and is drilled so the end of the connector is supported on the walls, end and flange.
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They can be gently tapped into tight galleries with this aluminum drift until the flange contacts the deck. Then the head gasket is installed and "O" rings over the connectors in the pocket in the head gasket.
Head is installed normally and torqued. Completed the "O" ring is fully supported, outside by the gasket, inside by the connector, and compresses for an oil tight connection.
These are re-useable but I keep spares to replace any damaged. This is cheap insurance, and superior to either split pins or roll pins.
 

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So one thing is, the block and head oil passages are not bored together, so they don't always line up perfectly. With the Norman kit, you tap the brass into the block, but for-darn-sure test fit to check alignment with the head passages to make sure they line up before final assembly. Sometimes a bit of hand work is needed.
Andrew
 

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Fortunately or intentionally, the "up" side (head) is smaller diameter than the block, so hole mis match while needing checking as Andrew suggests is not as likely as with connectors (roll or split pins) might be.
 

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Why didn't Alfa get the head gaskets made with the o-rings molded in them like every other car manufacturer?

Pete
 

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Here's a picture of them in place...
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Here's an old school practice. For our builds we like to use GM 6 cylinder valve stem seals. They have square shoulders which resist deforming, and fit perfectly. I've never seen one fail, even after a pretty serious overheat that required a full engine rebuild.
 
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