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Old 10-04-2011, 05:36 PM   #61
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Is there any way you could connect the pressure tester to an air compressor? If you could you could put the unit under water to see if it is leaking air when hooked up to the compressor and thus giving you bad numbers as a result. Maybe your past that point.
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Old 10-04-2011, 05:39 PM   #62
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Is there any way you could connect the pressure tester to an air compressor? If you could you could put the unit under water to see if it is leaking air when hooked up to the compressor and thus giving you bad numbers as a result. Maybe your past that point.
I could have and should have, but that still does not explain the leak through the exhaust.
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Old 10-04-2011, 06:10 PM   #63
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Yes, this is correct. You cannot dispute the howling air on the leak test through the exhaust. I was hoping to get a baseline number where the numbers were close on more than one cylinder, it's clear the engine is blown.

I'm also thinking I had detonation or something although I never heard it on the dyno. That's basically the only excuse for eroded, leaky valves.
I don't understand, aren't exhausts supposed to leak? If they didn't engines wouldn't run...

I'm with mgeoffriau, you need a proper compression tester before you do anything like pull the head.

It's bonkers to be worrying about something when there's no evidence other than a tester which gives funny readings on more than one car.
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Old 10-04-2011, 06:12 PM   #64
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I don't understand, aren't exhausts supposed to leak? If they didn't engines wouldn't run...

I'm with mgeoffriau, you need a proper compression tester before you do anything like pull the head.

It's bonkers to be worrying about something when there's no evidence other than a tester which gives funny readings on more than one car.
When I pressurized the cylinder, exhaust howls out the exhaust in all 3 cylinders except #4. Something is very wrong, regardless of the gauge. It's highly likely that both motors are screwed up.
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Old 10-04-2011, 06:15 PM   #65
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I would just pull it off. if its fine, clean it up, surface it and throw it back on.. If its screwed, I would get a VVT head..
I do agree though. If 1 exhaust is fully closed and all others leak, something is wrong. Regardless of what gauge you use..
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Old 10-04-2011, 06:18 PM   #66
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Did you make sure the valves were fully closed before you pressurized the cylinder? You did not just pressurize one cylinder to the other and not adjust the crank angle did you???
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Old 10-04-2011, 06:20 PM   #67
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I don't understand, aren't exhausts supposed to leak? If they didn't engines wouldn't run...

I'm with mgeoffriau, you need a proper compression tester before you do anything like pull the head.

It's bonkers to be worrying about something when there's no evidence other than a tester which gives funny readings on more than one car.
apparently, you guys don't know hustler.
if he had serious detonation, there would be broken rings/ringlands, before any valve problems. there would also be a hammertone finish on the pistons, which could be verified by putting #1 at tdc and shining a light in there.
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Old 10-04-2011, 06:30 PM   #68
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Did you make sure the valves were fully closed before you pressurized the cylinder? You did not just pressurize one cylinder to the other and not adjust the crank angle did you???
Calling Hustler.............
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Old 10-04-2011, 06:30 PM   #69
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I would just pull it off. if its fine, clean it up, surface it and throw it back on.. If its screwed, I would get a VVT head..
I do agree though. If 1 exhaust is fully closed and all others leak, something is wrong. Regardless of what gauge you use..
This is the plan, but I have to set here and obsess over it for about a week. This car can't take a VVT head. I don't need the power, I'd spend another $500 to get the head and another $700 to get a computer that will run the head.

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Did you make sure the valves were fully closed before you pressurized the cylinder? You did not just pressurize one cylinder to the other and not adjust the crank angle did you???
Comp TDC on every cylinder. I'm going home to check lash again. The exhaust side is a little tight for my taste.
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Old 10-04-2011, 06:35 PM   #70
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apparently, you guys don't know hustler.
It's been a while since I **** blood as a physiological symptom of stress. Maybe I'll get back there this weekend at the track when I think about the bill to tow my car home from the track incessantly while not enjoying the weekend.
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Old 10-04-2011, 06:48 PM   #71
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It's been a while since I **** blood as a physiological symptom of stress. Maybe I'll get back there this weekend at the track when I think about the bill to tow my car home from the track incessantly while not enjoying the weekend.
bill would be gas and maybe dinner or something. (hj) you have hardcore friends.
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Old 10-04-2011, 06:56 PM   #72
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bill would be gas and maybe dinner or something. (hj) you have hardcore friends.
Thanks, dude.
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Old 10-04-2011, 07:18 PM   #73
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When I pressurized the cylinder, exhaust howls out the exhaust in all 3 cylinders except #4. Something is very wrong, regardless of the gauge. It's highly likely that both motors are screwed up.
Which cylinder?

How do you know gas is escaping from said cylinders? have you pulled the exhaust completely?

Maybe the timing belt has just jumped?
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Old 10-04-2011, 08:50 PM   #74
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This is where a video scope would come in handy...
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Old 10-04-2011, 08:56 PM   #75
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This is where a video scope would come in handy...
it's too bad he lives so far away. i have a brand new snap-on scope in my hands right now. we've been probing dark deep holes all day. lol
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Old 10-04-2011, 09:29 PM   #76
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it's too bad he lives so far away. i have a brand new snap-on scope in my hands right now. we've been probing dark deep holes all day. lol
I bought a scope but it turned out to be a horrible piece of ****.
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Old 10-04-2011, 09:30 PM   #77
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Which cylinder?

How do you know gas is escaping from said cylinders? have you pulled the exhaust completely?

Maybe the timing belt has just jumped?
1, 2, 3. Because I can hear air hissing through the exhaust. I have not pulled the exhaust.
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Old 10-04-2011, 11:11 PM   #78
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How did you confirm TDC for each cylinder, dip stick test?

Are you sure that the crank didn't move a hair when you applied pressure? That can happen pretty easily, and when it does, the leak would likely be on the exhaust side.
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Old 10-04-2011, 11:56 PM   #79
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How did you confirm TDC for each cylinder, dip stick test?

Are you sure that the crank didn't move a hair when you applied pressure? That can happen pretty easily, and when it does, the leak would likely be on the exhaust side.
I was wondering this myself. What happens if you apply pressure and try moving the crank slightly by hand. Could a timing belt stretch enough to allow the valves to open slightly? Was the lash on all exhaust valves the same (primarily interested in #4 with respect to the others)?

You may just have some worn valve springs that aren't pulling the valves shut firmly enough.

EDIT: I recall a story similar to this from my auto mechanics class in high school. The car would drive normal, but the compression test or whatever would show a leak. It turned out that one of the valve springs actually cracked/broke so that it had enough spring to pull the valve shut, but not hold it shut very tightly.
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Old 10-05-2011, 12:07 AM   #80
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FWIW, when I've done leakdown tests, I often see the valves leaking slightly. I think it's due to bits of carbon or something getting stuck between the valve and the seat and preventing a complete seal. If you crack the exhaust valve open with pressure in the cylinder, that'll usually blow it loose, then go back and it will seal.

--Ian
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