LT5 Assembly Project

[HAWAIIZR-1]

Lee,

Sorry to hear about this setback. I know when Greg VanDeventer was working on my heads there were a lot of things to consider and even with trying to get the right valve guide seals I went through some gyrations with that. To further complicate it with aftermarket camshaft grinds he worked very closely with Aaron Scott since my cams were from SGC and then we went back and forth with Jerry and Kurt about the seals till we got the right ones. I don't remember all the technical details, but these LT5s really do require some Specialists in some areas; GVD reallys knows his stuff with these heads and can surely fix the issues if needed. I hope it all works out for you. Best wishes.

Craig

[LGAFF]

Guess it was not clear, previous pics I posted are video links showing the valves leaking.....(they make the porting look bad, its actually very good)

[LGAFF]

Well, shop called, they said no issues with the valves, that they relapped them checked them with Dykem(blue ink) and it shows a seal. I did find out that I had an issue with the valve guides, I was not aware the 90 Exhaust guides needed to be ground down before using seals....so I will be ordering 16 more guides.

I need to read Jerrys website:




Valve Stem Seal Set. Fits 91~95 ZR-1 LT5. NEW AND IMPROVED! effective 12 Jun10.

•Direct replacement of OEM valve stem seal.
•Even lower installed height than OEM seal, providing clearance for very high lift cams
•Positive seal, metal jacket design with garter spring for extended effective sealing of valve stem
•Outstanding valve spring clearance
•Serrated ring design and interference fit provides excellent stability on valve guide
•Manufactured with Viton for superior resistance to heat and wear durability
Always sold from stock on our shelf, just like all of our other products required. Sold by set of 32 only. Not sold individually. Direct replacement on stock engines. Can be used on 90 model with machining of exhaust valve guides to same specs as remaining model years.

Note : Please see our Special Tool PN ST-10067412 for installing this valve stem seal properly without damaging the seal.


Add to Cart:

•Part # 10067412
•Shipping Weight: 0.1lbs
•14 Units in Stock

[XfireZ51]

Lee,

b4 u order them, call me. I have a complete OEM set.

[Bob G]

If you replace the guides then you will have to redo the seats
also did your shop grind the seats w/stone or with a cutter ?

[LGAFF]

Bob they use a cutter......they are going to cut the guides and have a valve seal they can use.

[LGAFF]

heads are back on the motor....rolling the dice and moving forward, machine shop found no issues outside the valve seals on the exhaut. Thanks jerry for getting them out fast......

Build moving forward!

[Blue Flame Restorations]

Congrats, Lee.

[Bob G]

Do you want me to stop & leak It

[A26B]

Originally Posted by LGAFF

heads are back on the motor....rolling the dice and moving forward, machine shop found no issues outside the valve seals on the exhaut. Thanks jerry for getting them out fast......

Build moving forward!

So, if valve seals were the only issue ,what did you find that prevented the engine from having compression on all cylinders?

Lee, just thinking out loud about a couple of things that could easily be overlooked.

1. valve spring seats are installed under all 32 valve springs.

2. insure the new guides are installed at the correct height. Theres not a lot of room between the underside of the spring retainer and the top of the stem seal when at full lift.

3. and, the all too infrequent problem of valve stem installed height too tall after valve & valve seat work has been performed. Hopefully the verified all of this individually on all 32 valves & ground the stem tops properly.

Any of these would be a real PITA to discover later.....