Compression Test on Junk Yard Car

[gav240z]

Hi everyone,

A friend and I are looking for a decent L28 in a junk yard and want to know what the best way to test compression would be.

 

If I bring a fully charged battery and connect it at the terminals then place a screw driver at the starter to bridge the connection it should kick over the engine shouldn't it? Provided the wiring in that area is in tact we should be able to kick it over enough to check the compression. Does anyone have a better technique or tricks of the trade?

[nat0_240_chevZ]

not the best but if doesnt have a starter then try the socket on the front pulley and comp tester (held by another on the front).

 

use a ratchet and get your mate to go like hell, wait till you get about 3 compression strokes = 6 rpm per cyl, ouch.

 

this reading will be lower than that on a car/motor with a starter motor.

 

see how you go otherwise, try one with a starter motor and then with the ratchet, and see what sort of margin you get as some idea of the difference between the 2.

 

nato

[XRQTR]

If you're gonna do the socket thing then try to get your hands on a cordless rattle gun, it will save alot of strain LOL, oh and don't forget a spare battery

[tattoo_ink]

nato's nailed it i recon ! dunno about the rattlegun thou maybe a air rachet.......or something that turns it over constantly rather than jolting it ? maybe take a starter with you would be the easiest way to attack it ? just a thought .