Rings or Valve Seals?
Thread Starter
Racer
Joined: Jul 2011
Posts: 455
Likes: 0
From: Dalton GA
Rings or Valve Seals?
Ok I have a 98' Corvette 100K on the clock. Before I put my cam in I never had a problem in the world. First time i installed the cam and all goodies. Well when I put the valve seals on I did a crap job becuz I did not use a socket and tap them with a hammer. So when I went to the dyno it smoke all full throttle and declaration. So I go back and change the valve seals again. Almost every seal was riding the valve except a couple.
So This time I replace with Fel Pro seals. Well this time it smokes only on the passenger side and only on hard acceleration and it smells horrible. I thought it was the PCV system so I changed it all over to the LS6 style. Didn't fix it so I go and check my seals once again and 2 of my exhaust seals were indeed riding the valves. One shop tells me I'm chasing my tell and it's my rings but my compression was good on both side and the passenger was actually about 10PSI higher than the driver side.
It's not really burning oil but I know it's oil smoke. I pulled the heads to check all pistons and cylinders. I'll post of pictures. Please help me!
These were the 2 with the valve seals raised!
So This time I replace with Fel Pro seals. Well this time it smokes only on the passenger side and only on hard acceleration and it smells horrible. I thought it was the PCV system so I changed it all over to the LS6 style. Didn't fix it so I go and check my seals once again and 2 of my exhaust seals were indeed riding the valves. One shop tells me I'm chasing my tell and it's my rings but my compression was good on both side and the passenger was actually about 10PSI higher than the driver side.
It's not really burning oil but I know it's oil smoke. I pulled the heads to check all pistons and cylinders. I'll post of pictures. Please help me!
These were the 2 with the valve seals raised!
Thread Starter
Racer
Joined: Jul 2011
Posts: 455
Likes: 0
From: Dalton GA
I have had heads for awhile so I decided to get them out together my a machine shop. So I can be sure the seals are the correct size are installed correctly.
Compression test was done the first time the seals were bad. And they were all 175-185PSI.
Compression test was done the first time the seals were bad. And they were all 175-185PSI.
Thread Starter
Racer
Joined: Jul 2011
Posts: 455
Likes: 0
From: Dalton GA
That's the reason I'm letting a reputable engine builder/ machine shop put them together. So he can measure and check it all. I think that it's the seals but if it still smokes after I get the heads about then I know it's the rings. So we'll see I guess.
Thread Starter
Racer
Joined: Jul 2011
Posts: 455
Likes: 0
From: Dalton GA
Here is a picture of the passenger side head. And that is antifreeze on the chamber not oil.
Also I found this today. Its an indention in my piston. It was cover in carbon build up and I got in all out and its about the size of a beebee but it's not a hole just an indention. Could that have anything to do with my problem.
Also I found this today. Its an indention in my piston. It was cover in carbon build up and I got in all out and its about the size of a beebee but it's not a hole just an indention. Could that have anything to do with my problem.
Le Mans Master
Joined: Mar 2002
Posts: 5,955
Likes: 161
From: PNW
Is that the only piston with the indent? Sometimes pistons have something like that to indicate orientation when installed. It's not the reason for oil consumption or smoking.
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Thread Starter
Racer
Joined: Jul 2011
Posts: 455
Likes: 0
From: Dalton GA
Ok so I took the heads to get assembled and I look at all the cylinders really well and every piston has that same indention in the same spot. What is that? I don't think it's the cause of my problems but just wondering if anyone else has seen that.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
As stated, piston indents are for assembly orientation. I still think your issue is the valve seals. Get the GM seals, which will stay put when installed. Also, get the manual as there is a procedure and measurement to ensure correct installation of the seals.
Also, so you don't get in deeper, if the shop does any work to the heads and specifically the valve seats, you will have to re-check rocker geometry and correct. This may also require new pushrods. Personally, I would lap the valves into the seats while the heads are off the car.
Also, so you don't get in deeper, if the shop does any work to the heads and specifically the valve seats, you will have to re-check rocker geometry and correct. This may also require new pushrods. Personally, I would lap the valves into the seats while the heads are off the car.
