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leak down results 2nd motor

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Old 02-16-2009 | 04:44 PM
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Default leak down results 2nd motor

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?????????

Last edited by rssteiny; 02-16-2009 at 05:49 PM.
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Old 02-16-2009 | 06:14 PM
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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.
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Old 02-16-2009 | 11:49 PM
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Head gasket for sure. It needs to be fixed or it could ruin the block and/or head.
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Old 02-17-2009 | 12:05 AM
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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.
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Old 02-17-2009 | 08:02 AM
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Originally Posted by 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.
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.
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Old 02-17-2009 | 08:35 AM
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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.
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Old 02-17-2009 | 03:38 PM
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Originally Posted by 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.
Yes they are roller lifters, i will inspect them and if they look good reuse them.
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Old 02-17-2009 | 04:12 PM
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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.
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Old 02-17-2009 | 04:18 PM
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Originally Posted by 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.
Thanks will do
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Old 02-17-2009 | 05:11 PM
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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.
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