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Discussion Starter #1
Yes friends, it was not pretty. It has been over a year since we started the project and a little over a week ago we got her started. She would only run on starting fluid, but the fix for those issues is another story. Thank God the fuel injection was not operating, because upon pressuring the coolant system I could hear a bubbling in the engine block. The coolant level was dropping and the "oil" level was rising. It was not a good day in the shop.
A week later we dis assembled the engine, but did not see anything out of order. Today we started checking clearances, when the new liners with new O rings are dropped into the block there is approx. .013 protrusion, when the liners are compressed into the block the protrusion is approx. .002. This all seems to make sense. Y/N?

Question: sealant on the O rings?
: sealant on the head gasket?

thanks
 

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Sorry to hear of it. Cylinder protrusion sounds right but should be by the book. I've never used sealant on the head gasket O-Rings (are your roll pins in place?), nor any sealant on the head gasket except a bit in the back depending upon what particular engine and what gasket you have. Several threads here about that that topic. Some folks advocate a thin smear of permatex sealant just below the cylinder O-Rings. I've done it both with and without, did not have a problem either way.
 

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Discussion Starter #3
Roll pins are in place, but a few are almost flush with the block. Looking back, I may have rotated the crank with the liners NOT held down with the retainers. May have been a large mistake.
Hopefully we can get her together without incident this time, this is my first engine rebuild in 30+ years, so maybe it is coming back.

thanks to all for your help/support
 

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Did you put Ultra grey or similar sealant around the holes at the rear of the head gasket? Leakage there is a well known way of getting coolant in the oil.
I once had a new head gasket leak coolant into the oil because I did not torque it properly. I cleaned the male threads on the studs but not the female threads in the nuts. There was sufficient foreign material on those threads to give me false torque readings.
When I did my most recent engine build I used a little Ultra Blue on the liner O rings as advised by my guru - RJ.
 

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Discussion Starter #5
Ed,
I did not use sealant for any gasket during assembly. After this minor incident and reviewing several other threads, I may pull the rear main cap and use a silicone product. The ultra blue and ultra gray silicone based? About 25 years ago I started using Dow Corning medium modulus sealants and cannot remember if they have ever failed.

Thanks for the tip with the "Ultra" products.

BTW, where around the rear portion of the head gasket is there a potential leak, and the sealant recommended?
 

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Discussion Starter #7
Instructions

If I recall the Alfa factory assembly manual as being specific with "no sealants of any type". After reading several threads pertaining to Alfa engine assembly we will be using gobs (maybe not that much) of sealant. We already have several Porsche models that require a cardboard mat to catch the oil leakage.
 

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If I recall the Alfa factory assembly manual as being specific with "no sealants of any type".
That was correct at the time but IIRC there was a design change that resulted in the only good gaskets being for the later motors and the earlier ones need the Ultra-grey.
 

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Definitely give the rear main cap attention. The original seals were a bear to install but if done right would not leak for many years. I have found cigarette seals being sold now are just a tad too small in diameter and require sealant.
 

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I agree with the advice about the rear main seal if you are pulling the engine down that far but that is unlikely to be the cause of coolant in your oil.
 

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Discussion Starter #11 (Edited)
stripped

We have stripped the engine down to the crank w/caps and front timing cover. Given the condition it does not appear these need attention. I will research the GM valve stem seals for the block/roll pins and apply silicone with new cigarette seals. On the plus side, we can reinspect all the components and this was intended as a "practice project" from the start.

Also sealant will be applied to the head gasket rearmost surface
 

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Have you checked the gasket between the front cover and the block? This gasket has 2 holes in it, 1 for oil (with a square rubber ring) and 1 for water. Also there are 2 different gaskets for that side, with different hole spacings. Check that you have the correct one.
 
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