: *new problem with my project, compression


FocusMang
07-14-2005, 02:27 AM
It seems the latest problem with the car now (still not running) is the oil pressure? The shop claims I have 155psi across all 4 holes with a compression test, but when the engine is running there is little to no compression in all 4. They checked the head twice they claim and there are no problems with it. They claim its the oil pump not providing enough pressure to raise the lifters. So basically the car still doesnt run or idle at all.

crazymechanic
07-14-2005, 07:58 AM
well, given that the zetec engine (I assume you have a zetec) doesn't have hydraulic lifters, that explanation is a bunch of BS. we have a mechanical valvetrain. get the camshaft timing double checked. you're probably off by a tooth or two

1turbofocus
07-14-2005, 08:07 AM
What is your static compression meaning 8.5 , 9.5 , 10 to 1

Tom

FocusMang
07-14-2005, 09:16 AM
Im not sure on that. The pistons are JE 9-1

I figure its something to do with timing? But these guys have tried with it long enough to give up. I told them not to mess with the head, and they tore it apart and cut the valves a week later, but they claim they have had the head checked by 2 places and its fine. So far I have heard all these reason why the cars not running

-When the engine is warm the piston rings swell
-Its a bad engine
-The Ford oil filter is junk
-My Garrett turbos design is wrong
-My turbo setup is wrong
-My Ford Lightning Maf is junk
-My #42 injectors are TOO big (im trying to reach 300hp)

Scandelous
07-14-2005, 01:32 PM
1. How are you going a compression test with the engine running?
2. Are you doing the compression test with the engine hot or cold? You are right that as the engine warms up that the forged pistons will expand a bit and you will get a more accurate compression reading. However, 155 psi is low of a 9.0:1 compression engine. I have JE 8.8's and my compression is 180 across. That could be why they are saying the engine is bad. It will still start and idle with that low of compression.
3. I'd rule out that Garrett designed your turbo wrong.
4. If the oil filter is clogged then there would be a problem with the oil flow. I would check the oil pump too.
5. It doesn't matter what kind of turbo is on the end of the manifold bolted to the engine. The turbo has no affect on the cars idle what so ever.

FocusMang
07-14-2005, 03:36 PM
1. no
2. cold 155 in all 4, when its warmed up a little bit its making 70-110 across the 4

BlueZetec
07-14-2005, 04:18 PM
I just got my engine rebuild and changed a bunch of stuff in it, one thing that not to idle first was throttle p. sensor wasn't installed right on the new FC 65mm TB, then everything else was tuning, still is. Low conpression shouldn't make big difference on wether it idles or not, 42lbs are not too big, MAF not ideal but not the problem. turbo-idle no conection, oil flow-idle no conection unless engine is been run without oil and the bottom end is no messed up that it wouldn't even crank. But hey, this is only my opinion.

1turbofocus
07-14-2005, 06:35 PM
Originally posted by FocusMang
1. no
2. cold 155 in all 4, when its warmed up a little bit its making 70-110 across the 4

If your compression goes from 155 cold to 70 to 110 warm than your engine is dead

You need to find a shop to do your tuning properly and to where if you have a problem they can at least tell you what the problem is

Any shop that you take your car to that cannot tell you what the problem is when there is a problem are parts changers and not machanics

Tom

Scandelous
07-15-2005, 09:23 AM
Wow, in your first post you didn't state that the compression was that low. 70 psi of compression means a dead engine.