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easy compression test with motor out of car?

Old Jan 18, 2008 | 06:30 PM
  #1  
spills's Avatar
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From: Buford, GA
Car: 89 RS
Engine: 6.3L Megasquirted HSR
Transmission: T56
Axle/Gears: 3.70 Posi 9 bolt
easy compression test with motor out of car?

I pulled my motor out for some cleanup reasons, and Ive noticed that it's been smoking a little more than Id like. I dont know if the mixture wasnt right or if Im lekaing oil or coolant into the cylidner somewhere. This is the first motor I built so Il a littke sketchy. Id like to do a compression test on it now while it's out of the car, seems it would be easier to fix leaks that way. Most compression testers Ive seen require to remove one of the apark plugs and turn the motor over. However, the starter isnt hooked up and (for the time being) there's no oil in the motor either. Is there a way to check compression with the way my motor sits right now? I suspect some piston ring failure from the looks of it, but I want to be 100% when i reinstall the motor. Thanks!!!
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Old Jan 18, 2008 | 07:41 PM
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Re: easy compression test with motor out of car?

no. not really an easy way. I guess you could put it on a stand and hook up a starter and go at it. never done it that way myself.
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Old Jan 18, 2008 | 08:28 PM
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From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Re: easy compression test with motor out of car?

More useful than a compression test is a leakdown test, which doesn't need the starter, but does need compressed air.
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Old Jan 18, 2008 | 09:09 PM
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spills's Avatar
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From: Buford, GA
Car: 89 RS
Engine: 6.3L Megasquirted HSR
Transmission: T56
Axle/Gears: 3.70 Posi 9 bolt
Re: easy compression test with motor out of car?

ive heard of leakdown testers before from my DSM days, couldnt I make one pretty cheap? IIRC those things arent cheap to buy off the shelf. Ive got 155psi air at the shop
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Old Jan 19, 2008 | 12:16 AM
  #5  
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From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Re: easy compression test with motor out of car?

They're pretty easy to make with a handful of brass fittings and a couple of gauges.
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Old Jan 19, 2008 | 08:27 AM
  #6  
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From: Adrian, Mi, USA
Car: 1988 Pontiac Firebird Formula
Engine: 5.7 TPI
Transmission: 700R4
Re: easy compression test with motor out of car?

Actualy, the gauge sets really aren't that expensive, and are EXTREMELY useful...... tells alot more about an engine that a simple compression test.
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