rssteiny

500 hps motor cold not run in 5 months

1 11%
8 10%
4 15% leakin out exhaust port
3 28% leakin out exhaust port
6 9%
5 10%
7 11%
2 57% leakin out plug hole beside it (head gasket i
assume)

time to pull heads and redo?????????

DMOORE

Yes, pull the heads and inspect/ refresh. 28% and 57% are signs of a real problem. Do it now and save cash in the long run.



Darrell.

Griff

Head gasket for sure. It needs to be fixed or it could ruin the block and/or head.

Griff

Seeing all the numbers from both engines, I would be inclined to pull them both out.

I would at a minimum, pull the heads and get valve jobs and new springs. You could also mill the heads .020-.030 for a slight compression boost.

You could also check or have the cylinders checked with the heads off to evaluate further, but I really think the bottoms will probably be fine for another 400hrs.

Of course you could always do full rebuilds like you were considering. If the bottoms are in good shape, you might just need honing, polishing, rings and bearings.

rssteiny

If i just do heads and cams do i need to replace lifters as well do to hours, or will they be ok if they look fine. also chain and gears, i assume.

hoozeyurdaddy

if lifters are roller, they can be reused. If they are flat tappet, they should be replaced with the cam. never reuse flat tappet lifters with a new cam.
chain and gears are cheap enough, change them.

rssteiny

Yes they are roller lifters, i will inspect them and if they look good reuse them.

Thunderstruck

If you don't take out the motor with the bad head gasket and send it to a machine shop, make sure the deck hasn't been eroded between 2 and 4 on that motor.

Git R Dun spring is springing.

rssteiny

Thanks will do

Griff

I would not reuse the lifters with that many hours on them. A broken lifter can trash the entire engine. If you go to a larger cam, I don't think you'll be able to use the GM roller lifters anyway.