compression leakdown results!

-
H

hamesdart

Well-Known Member
Joined
May 26, 2008
Messages
347
Reaction score
0
Location
souther cali
well guys Since i have had my dart i have only really done a regular compression test to see what kinda shape it was in. I just bought a tester and ran it on a few cylinders....
So 1st i tested with low oil & cold engine since I was impatiant :toothy10:
got 30% leakdown, Then i ran to the store and got oil fired it up, pissed off the neihbors and tested again.
Got about 2-5% on it. Kinda unbeliveable since its stock bore and from what I was told it has never been re-built but looked like it had a cheap line bore once. I tested with all the other spark plugs in as well... dont know how important that part is.
I was trying to see if my tax return was going towards a re-build or getting the interior and rest of the car done.
What do you guys think!?!?!?
 
woohooo! thats what I wanted to hear.
Pulling the motor again and spending upwards of 2500 because I had no choice was gonna suck as opposed to wanting to when I had extra money, or instead of finishing the rest of the car for the same amount of money.
 
Good results. The next time tho.. the way you test compression is with the plugs out and the engine hot, and the throttle blocked wide open. Compression testing give a PSI for each cylinder. If you bought a leakdown tester and leaked it down, you should get two pressures and you figure the percentage loss. 30% might be ok cold for that but I dont think you'd see 2% warm on stock engine with some miles. So I'm not sure which one you did, but if it went way up when things were warmed up, and it runs well, like he said... do the interior...lol
 
Well running compression test I do take all the spark plugs out.
But when I ran the leakdown test I left the rest in...
My first reading was 30% since I ran it cold and the oil hadnt sealed the rings. Then as I warmed it up a little more it went to 15%
At true operating tempeture it was 2-4 % and then the next one I tested as it after cooled down a little I got maby 3-5% so it just showed how much getting the temp up and letting the oil seal the rings is important.
The motor as Far as I was told had never been re-built and its stock bore but I can tell someone did a quick line hone on the cylinders so I belive with these numbers it may have been cleaned up a bit and maby been re-ringed.
 
ok. I wasn't sure which test you did. My apologies for misunderstanding. Also just for clarity the cylinders get "honed". The main bearings get "line honed". It had something done at some point. Prob just rings/bearings..
 
yah we belive the cylinders got a cheap hone job at the least since we could see it in the cylinders but we never checked bearings and such for dates and all that.
I think they just gave it a cheap quick once over. We only had it to a shortblock once before we went on pinks all out and we were on an unbeliveable time crunch and didnt get into the short block.
All tested well though so I think I can get a few years or so out of this motor while I save for a stroker build. woohooo
 
You must log in or register to reply here.
-

Back
Top