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My Compression has fallen and can't get up!

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Old Dec 26, 2001 | 07:41 PM
  #1  
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Default My Compression has fallen and can't get up!

Leakdown test confirmed #5 is dead. That explains the poor showing for my car despite the recent addition of heads and a bigger cam.

Over the next week or two I'll be exploring my options from mild to wild.

New sig.
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Old Dec 26, 2001 | 07:43 PM
  #2  
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Default Re: My Compression has fallen and can't get up!

Joel, I'm sorry to hear that buddy. Do you have any idea how it happened ?? What are you going to do about it ?

Mitch
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Old Dec 26, 2001 | 08:08 PM
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Default Re: My Compression has fallen and can't get up!

They make these little blue pills for that...err wrong thread. Sorry <img src="gr_stretch.gif" border="0">

Do you think this is from the blower episode?

You might be able to get away with a new piston and rings depending on what things look like when you tear it down.

While its tore apart you could have the block sleeved and bored out. <img src="gr_stretch.gif" border="0"> While thats getting done you might as well throw a stroker crank in there. <img src="gr_stretch.gif" border="0"> Of course then you would need a set of Stage III LS6 heads to go with the bottom end. Wow, next thing you know you've got a

422ci bad *** vert. <img src="gr_grin.gif" border="0"> You could call it "White Lighting" or something.

That would be my vote.

Sorry to hear about your troubles but, it gives you a good excuse to go wild. <img src="graemlins/burnout.gif" border="0" alt="[Burnout]" />

<img src="graemlins/gr_cheers.gif" border="0" alt="[cheers]" />

Johnnie

[ December 26, 2001: Message edited by: XLR8NSS ]</p>
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Old Dec 26, 2001 | 10:53 PM
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Default Re: My Compression has fallen and can't get up!

Have you checked for broken valve springs.A friend had the sam on 2 and 4.Come to find out he just had broken valve springs. <img src="gr_sad.gif" border="0"> <img src="gr_images/icons/mad.gif" border="0">
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Old Dec 26, 2001 | 11:40 PM
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Default Re: My Compression has fallen and can't get up!

If you don't have a blown headgasket, and the motor is not chugging like it's got a cracked ring, I'd bet it's a bent pushrod or a broken spring.
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Old Dec 27, 2001 | 12:41 AM
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Default Re: My Compression has fallen and can't get up!

[quote]Originally posted by Pro Stock John:
<strong>...and the motor is not chugging like it's got a cracked ring, </strong><hr></blockquote>

Sorry to interupt your thread, but would a cracked ring cause the motor to consume coolant?

Thanks a lot,
Chris G
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Old Dec 27, 2001 | 01:16 AM
  #7  
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Default Re: My Compression has fallen and can't get up!

I can't see how, unless it cracked through the cylinder liner into the water jacket! <img src="gr_eek2.gif" border="0">
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Old Dec 27, 2001 | 01:24 AM
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Default Re: My Compression has fallen and can't get up!

[quote]Originally posted by Chris G:
<strong>

Sorry to interupt your thread, but would a cracked ring cause the motor to consume coolant?

Thanks a lot,
Chris G</strong><hr></blockquote>


Chris, since coolant does not actually flow inside each cylinder, a cracked ring alone wouldn't cause for any coolant usage. Only a **** load of oil and loss of compression <img src="gr_tounge.gif" border="0"> . My guess is you have a hair crack in the head somewhere.


Josh
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Old Dec 27, 2001 | 08:12 AM
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Default Re: My Compression has fallen and can't get up!

PSJ:
We pulled the valve cover and visually inspected the springs without removing them and there was no sign of damage. They are new springs. I could pull the springs if there is really a chance its just them.

We pulled the pushrods and they are fine.

When doing the leakdown, we could not detect air from the exhaust or intake, but you could hear it plain as day when you popped the oil filler cap.

The motor does have some stumble to it, which is why we started testing for misfires. #5 always showed a lot of misfires under light throttle cruise.

Since fixing the head gasket, I'm not using any coolant.

Mitch:
Answers to your questions:
1) Detonation when I had the S/C installed.
2) Remind me where you park your car at night. <img src="gr_grin.gif" border="0">

XLR8NSS:
A 422 vert would be cool. If we could get every member on the board to send me $5 I could do it. <img src="graemlins/gr_cheers.gif" border="0" alt="[cheers]" /> Realistically, if I go bigger cubes, I'll either go stroker or bore, but not both; just too much money to explain to the wife. <img src="graemlins/gr_punch.gif" border="0" alt="[fight]" /> <img src="gr_images/icons/wink.gif" border="0">
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Old Dec 27, 2001 | 08:50 AM
  #10  
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Default Re: My Compression has fallen and can't get up!

[quote]Originally posted by Ragtop 99:
<strong>Mitch:
Answers to your questions:
1) Detonation when I had the S/C installed.
2) Remind me where you park your car at night. <img src="gr_grin.gif" border="0">
</strong><hr></blockquote>

Lol !! <img src="gr_sad.gif" border="0"> You don't want to know where I park my poor baby at night ..... in my driveway in the freezing cold under a blanket of snow. <img src="graemlins/gr_cry.gif" border="0" alt="[whiner]" />

Some day I'll manage to get my garage emptied and cleaned out.

Good luck fixing the problem, I always hate problems like this but it often makes it easier to tell the wife you need to spend a couple thousand $$$ on the car <img src="gr_images/icons/wink.gif" border="0">

- Mitch
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Old Dec 27, 2001 | 11:04 AM
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Default Re: My Compression has fallen and can't get up!

No compression whatsoever?
You have zero compression in #5? Even a motor with a cracked ring will show some compression. Car idle rough, excessive valvetrain noise? Is the #5 plug wet? Depending on how a valvespring breaks is it always possible to see the broken spot? If you have no compression in one cylinder it's like the valve is hanging open.


Using Coolant?
God knows I broke a ton of stuff. Here's how I check to see if a motor is using coolant. In the morning, I pull off radiator cap. IMO it should be full to the top. If it's not I top it off. Then I start the car up. I continue to top it off until after the t-stat has opened up. If it continues to use coolant there might be a problem, start checking the exhaust to see if it's got a whitish tinge to it. Burning coolant has a distinctive smell too.

I repeat this for like three days. I also check all lines for drips and leaks. If you have an aftermarket tranny cooler definitely check all the connections many times you can loose a small amount of coolant on a weekly basis. If you did heads and cam check all the big clamps again for dripps and leaks.

Next
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Old Dec 27, 2001 | 11:50 AM
  #12  
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Default Re: My Compression has fallen and can't get up!

yekkk! the 98 with the twins , well it sounds like the same thing about 1/2 piston was gone,2 others on the pistons were the rings go were cracked.hope this does NOT HAPPEN TO YOU. MICHAEL <img src="graemlins/gr_cry.gif" border="0" alt="[whiner]" />
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Old Dec 27, 2001 | 02:26 PM
  #13  
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Default Re: My Compression has fallen and can't get up!

[quote]Originally posted by Ragtop 99:
<strong>
If we could get every member on the board to send me $5 I could do it.</strong><hr></blockquote>

Welp, heres my contribution. Now if you figure some way to spend it let me know. <img src="gr_images/icons/wink.gif" border="0"> <img src="gr_grin.gif" border="0">



[ December 27, 2001: Message edited by: XLR8NSS ]</p>
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Old Dec 28, 2001 | 08:04 AM
  #14  
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Default Re: My Compression has fallen and can't get up!

I have some compression, but a 60% loss using a snap-on leakdown tester. Test 2 other cylinders and they show in the green zone, around 10% loss. Yes the car has been running rough but we put in the TR 224 112 cam (had a 218/218 114), so at first everyone told me it was the cam. You can feel a stumble on the highway at light throttle, say 50 mph 4th gear lock-up. ATAP will show tons of misfires at that point.

I've been monitoring the coolant since we put the car back together. Been full to the very top every time I check and coolant overflow bottle level has been pretty constant, so I'm pretty sure that I'm not using coolant. I've put on about 1,000 miles and there is no evidence of usage.

Johnnie, that's so generous <img src="gr_grin.gif" border="0"> Do me a favor, printout out a bunch of them, put them in your bank account and send me a bank check. You know its not safe to send cash through the mail. <img src="gr_images/icons/wink.gif" border="0">

[ December 28, 2001: Message edited by: Ragtop 99 ]</p>
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Old Jan 2, 2002 | 10:11 AM
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Default Re: My Compression has fallen and can't get up!

You have shattered a ringland unfortunately. I bet when you take it out it will fall apart in your hand.
Sorry to hear about it man.
If you are going to upgrade your motor definitely go all bore. Much cheaper and the power gains are higher than from a stroker alone.
Good luck,
Chris
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