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Discussion Starter #1
Ordered a Motronic piston/liner kit, came with everything, pistons, liners, rings, wrist pins, clips, but no O rings for the liners? Do I have to source them myself?
 

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PM me your address and I will mail you a set
 

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Ordered a Motronic piston/liner kit, came with everything, pistons, liners, rings, wrist pins, clips, but no O rings for the liners? Do I have to source them myself?
The O rings typically come with the gasket set - not with the liner set. It's pretty hard to replace pistons & liners without replacing a bunch of gaskets at the same time, so I guess Alfa (or Borgo or ...) decided it was more logical to package the liner O rings with the gaskets than with the liners.
 

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Discussion Starter #4
I also ordered the full gasket set. I guess I should look in there before Alfaparticle sends me a set!
 

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I think your best bet (only bet) is to use Viton for all O-rings and seals. Regular rubber o-rings flatten out, get hard and crack! Don't use the stock o-rings in the kit, unless you know they are Viton -most are not.

Here is a link to uncle Paul's site:

Engine Seal Kit Bottom End 1300,1600,1750,2000 Spiders to '94 - Spruell Motorsport, Inc - Alfa Your Store for Sports Car Performance and Racing Parts

Edit: Oh, and throw away those darn cigarette seals. They shrink and allow oil to leak past them and the rear main seal. Just fill the cigarette seal cavity completely with 'Ultra Black' (or gray). There is a good youtube video that shows how it is easily done on an Alfa -just remember to install the three plates on the 'inside' of the crank that the fly wheel bolts, bolt into. This is easy to forget and that Ultra Black makes it very difficult to remove the rear main bearing cap if you forget. I found this out the hard way.

Mark
Mark
 

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Discussion Starter #6
Well, I looked in the kit and yes, there are O rings in it..... are they Viton? Haven't a clue.
 

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I also ordered the full gasket set. I guess I should look in there before Alfaparticle sends me a set!
The liner O rings should be in there.

IRONBLOCK said:
I think your best bet (only bet) is to use Viton for all O-rings and seals. Regular rubber o-rings flatten out, get hard and crack!
While I agree with IRONBLOCK - viton lasts longer than conventional rubber - I'm not sure how critical this is for the liner O rings. I say this because I tend to take the "belt and suspenders" approach to liner sealing. Since the sealing surface in the block is often a bit pitted, even viton may not seal well there. Consequently, I smear a bit of high temp RTV around the base of the liners (as well as use new O rings) before inserting the liners.
 

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Discussion Starter #8
I looked at the block pretty close, I didn't see any signs of putting. I will use the ones they sent but will be sure to give all the O rings a slight coat of red RTV when I assemble.... I do appreciate the input I get from you guys that have been done this road before.
 

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No mail today - Columbus Day. I will mail them tomorrow. These are the black ones made of EPDM or similar. The same ones that I use on my rebuilds.
 

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I looked at the block pretty close, I didn't see any signs of putting. I will use the ones they sent but will be sure to give all the O rings a slight coat of red RTV when I assemble.... I do appreciate the input I get from you guys that have been done this road before.
Not red!!

Ultra Grey.
 

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This Frank Silvia youtube video was a big help to me. He skips over a few details but at least you get an idea of what you are getting into. I was very fortunate to have an experienced former race shop owner/mechanic & friend (Ernie Cabrera) help guide me along the path. Um, he saved my bacon a time or two...make sure to measure everything you possibly can and compare to the specifications. I bought a 'special set' of Hastings oil control rings for my new 1600 pistons and they turned out to be the wrong size (3.5 mm v. 4.0 mm)!


The engine turned out great and it runs like new. One thing that I wish I had done (and may still do) would be to use a 'Thread Sealant' on all the oil pan bolt threads and differential sealing bolts. I used ultra grey around the bolts holes but not on the threads and some oil gets past the bolt heads. I understand Lock-tite makes a thread sealant too (in addition to their thread locking compound -Lock-tite, Red or Blue...which I don't really like because more often then not, I have to undo something with red and it is a PITA.

Be sure to smooth out where the front main seal runs on the front pulley with wet or dry sand paper (I used 400 or 600 grit). If the groove is too deep, there is a sleeve that you can buy to cover the groove. Also, I used Ultra grey on the outside diameter of the front and rear main seals, as well as the differential nose seal and the inner few threads of each with 'Red n Tacky' on the I.D. of the seals. And yes, the liner sealing o-rings, tiny as they are, do a darn good job of sealing (don't let them stay twisted though)!

Mark
 

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Discussion Starter #14
Thanks for the video! I have the shop manual CD with all the specs but nothing on procedure. This will help me familiarize immensely....
 
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