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Old 09-29-2009, 11:52 AM   #81
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Something we've yet to address is health of the engine. We're assuming it's a compotent mill with decent compression and leak down, but has this been confirmed? I believe you wrote earlier that you double checked mechanical timing to be spot on. What about the damper/crank pulley assembly? Is it OEM 1994? That can make a *huge* difference if it's failing.
The pulley is OEM 1994. When you say fail, how do you mean? I did confirm TDC with #1 cylinder and the mark on the pulley.

Health of the engine? I hope it's darn good! It's a new build but I suppose it wouldn't hurt to do a compression check.
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Old 09-29-2009, 11:57 AM   #82
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(Hell Scott, you might want to look into upgrading your MSI to MSII, it's a much better system [faster, better accuracy, better resolution, more feature rich]).

This is something I considered doing over the winter downtime.
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Old 09-29-2009, 12:51 PM   #83
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I think you are drowning it the very fact that your power falls off with the water speaks volumes to that man turn the water down considerably to maybe 3 gph or so and go up from there and you should see better results.
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Old 09-29-2009, 01:08 PM   #84
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The pulley is OEM 1994. When you say fail, how do you mean? I did confirm TDC with #1 cylinder and the mark on the pulley.

Health of the engine? I hope it's darn good! It's a new build but I suppose it wouldn't hurt to do a compression check.
if it's really new. i've seen cars go for a while before the rings fully seated. compression jumped waaaayyyy up afterwards. just a thought.
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Old 09-29-2009, 01:12 PM   #85
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if it's really new. i've seen cars go for a while before the rings fully seated. compression jumped waaaayyyy up afterwards. just a thought.
I'll test tonight.
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Old 09-29-2009, 03:34 PM   #86
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You don't have to guess on the intercooler as a bottleneck. Just check the pressure drop across it at your 16psi level. If it is a restriction you will see it.
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Old 09-29-2009, 03:43 PM   #87
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The pulley is OEM 1994. When you say fail, how do you mean? I did confirm TDC with #1 cylinder and the mark on the pulley.

Health of the engine? I hope it's darn good! It's a new build but I suppose it wouldn't hurt to do a compression check.
The pulley is basically a rubber sandwich. Interior rubber gets old and does not hold the pulley together. You'd have to check with a timing light on the dyno.

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This is something I considered doing over the winter downtime.
You should do it. Costs $100 and the fueling is 100x more accurate.
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Old 09-29-2009, 06:44 PM   #88
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Red face compression

***

Did the compression check, wasn't sure if the engine was supposed to be cold or hot, did it cold. numbers are bizzare:

cyl dry oil
1 172 300+++ (pegged the gage, bizzare)
2 110 150
3 140 152
4 170 190

WTF?????
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Old 09-29-2009, 06:47 PM   #89
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do that **** again when it's warm.
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Old 09-29-2009, 06:49 PM   #90
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do that **** again when it's warm.
I'll claim a little newb here, I assume you're supposed to do it with a warm engine? Would make sense with the forged pistons. Do i need to disconnect the coils when doing the test? I've heard stories of them blowing out without a load.
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Old 09-29-2009, 07:26 PM   #91
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Well I guess I'm fucked. #2 and #3 look to be very low. I only did the wet test on two and it went from 120 to 230. Too depressed to do the rest. This is a new build too, probably less than 1000 miles on it. Can I assume the rings were not installed correctly?


COLD

cyl dry oil
1 172 300+++ (pegged the gage, bizzare)
2 110 150
3 140 152
4 170 190

WARM

cyl dry oil
1 182
2 130 230
3 160
4 180
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Old 09-29-2009, 11:57 PM   #92
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Quote:
Originally Posted by thymer View Post
Well I guess I'm fucked. #2 and #3 look to be very low. I only did the wet test on two and it went from 120 to 230. Too depressed to do the rest. This is a new build too, probably less than 1000 miles on it. Can I assume the rings were not installed correctly?


COLD

cyl dry oil
1 172 300+++ (pegged the gage, bizzare)
2 110 150
3 140 152
4 170 190

WARM

cyl dry oil
1 182
2 130 230
3 160
4 180
I assembled an engine, and did not compress the rings properly on one piston. It hung up on the deck going down. I chipped a piece off the ring right at the gap. I was unaware that it happened, and continued to assemble the engine. I ran it a while, and always noticed that one venturi on the first carb had a different vacuum value. After doing a compression test, I thought that I blew a head gasket. When I found no problems with the head gasket, I disassembled the motor and discovered the problem.

You should first check the head gasket (obviously) before tearing down the motor. You might get lucky.

One final note. Correct me it I am wrong, but you should remove all spark plugs, and take a compression reading after about three engine revolutions.

Good luck man.
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Old 09-30-2009, 12:00 AM   #93
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After thinking about it a minute, I see that #2 and #3 is low. That is a pretty good clue that it is in fact a head gasket. Gases are probably flowing between the two cylinders.
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Old 09-30-2009, 01:05 AM   #94
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um dude was your throttle open while cranking? The middle 2 numbers are pretty low yeah
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Old 09-30-2009, 09:10 AM   #95
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um dude was your throttle open while cranking? The middle 2 numbers are pretty low yeah
Yeah, throttle wide open. I guess it's time for a leak down test. They all went up with the oil so I'm thinking it's possible that leaky valves could be my issue as well? I'd be surprised if it was the head gasket, I even re-torqued it after the first couple hundred miles. This sucks beyond all belief. I had the engine shop do the block machine work and assemble the bottom end....

I can handle it if it's just a valve issue, good excuse to get a 99 head I suppose. Any thoughts out there?
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Old 09-30-2009, 09:38 AM   #96
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Did you build it? that changes everything if so.

But if someone else assembled it. Will they stand behind there work?
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Old 09-30-2009, 09:48 AM   #97
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Did you build it? that changes everything if so.

But if someone else assembled it. Will they stand behind there work?
The bottom end was assembled by my machine shop. Pistons, rods, crank.
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Old 09-30-2009, 10:19 AM   #98
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It tests the leak down else it gets the hose again.

Seriously, needs to be leak down tested to see where pressure goes. You should be able to hear the air escaping and make a judgment before taking ratchets to the engine.
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Old 09-30-2009, 10:56 AM   #99
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ima thinking its the rings or pistons given the results with oil. I hope i am wrong and its just something dirty and not sealing right.
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Old 09-30-2009, 11:01 AM   #100
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yeah, probably didn't seat the rings good or something lame.
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