CW00BlackTA

iTrader: (31)

I posted about this a few weeks ago--burning a quart every 100-200 miles. This is on a 50K mile car that burned about 1 quart every 2500-3000 miles before the cam swap. I've seen a few other posts about increased oil consumption after a cam swap so I thought I'd share what I've found so far.

The only things I could think of that might cause this would be bad valve seals or the PCV system. The valve seals were the only thing that was changed. I thought about the new cam affecting the PCV system so I took a look inside the throttle body and didn't see any pools of oil or anything. To make sure this isn't an issue, I put a small breather on each valve cover.

Next I pulled the valve covers to take a look at the valve seals--which came with a Patriot dual spring kit I bought from someone on the board. While getting there, I noticed 6 of 8 plugs had oil on the threads. I pulled the first two valve seals and compared them closely with the stock GM seals I just purchased. Neither appeared damaged in any way. However, the seal inside diameters appear to be larger on the seals I pulled off--where it seals to the valve stem and where it seals to the valve guide. I asked my wife to take a look at them and she noticed the difference right away. I'm not sure if these were the wrong seals or if those diameters changed that much from being installed--wouldn't think so. The new GM seals seemed to install the exact same as these did. I guess I'll find out tomorrow when I get it back together. I'll post again with the results.

CW00BlackTA

iTrader: (31)

Sorry for the slow follow-up. My cam spring tool broke and then I had to work a ton of OT this week. Didn't get it done and drive the car again until today. I don't have the tell-tale smoke coming out the exhaust like I did before. That's a good sign. It's been raining all day so haven't pushed it yet either. I plan to put some miles and testing in this weekend and will report back one more time after I've had a chance to check and see what my oil level is doing.

slammedchevy

iTrader: (13)

did you put the right seals on. the exhaust and intake are different part numbers if you put intake on the exhaust you could burn it up because its not ment to handel heat. ive seen that before

CW00BlackTA

iTrader: (31)

The kit (Patriot Gold dual spring kit) came with all exhaust seals--which is fine. It was supposed to be for an LS1 engine. I replace those seals with new GM exhaust seals and they were slightly different than the first set. The first set was installed correctly and there was nothing wrong with them other than the dimensions appeared to be different. Not sure what the story was with the first set.

DaddySS

Thanks for the follow up, keep us psoted.

racecar

Exhaust guide seals usually don't cause oil loss problems because when the exhaust valve is open, there is positive pressure in the port, not vaccume. The intakes are the problem, due to high vac at partial lift, or on de-cel. A small change in seal diameter could cause a big problem. I have total Seal piston rings that have 0% leakdown, that;s right 0. On the intake stroke there is heavy vac in the intake port that is trying to pull oil down the guides. My engine with 1000 miles on new GM LS6 heads had a smoke problem. I had to change from the stock GM black neoprene intake seals, to Viton rubber, that seems to have solved it. The new seals felt like the same fit on the valve stems. The old ones were just not the right material for this motor.
My observation:: if anything is wrong with the intake seals, there will be smoke problems. Sounds like you are in the same ball park.

1BAD98LS1

iTrader: (33)

Thats correct, the intake ones have a red seal around the top as do the exhaust ones have a black seal around the top and are slightly shorter. this could cause a bit of consumption.

GuitsBoy

iTrader: (4)

A lot of people simply dont press the seal on far enough. It takes quite a bit of pressure to seat those seals home. If you use the deep socket to push them on, the palm of your hand should be sore and red by the time youre done. If you tap them on, make sure you tap till you hear it seat fully. Ive seen many cases where the seals are riding up and down the valves, and allowing oil to get into the cylinder.

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