Northern California Ford racer's Message Board Forum Sell & Buy Ford Parts in Northern California Classifieds Mustang Pictures / Videos of Ford Cars in Northern California

Northern California Ford Owners  


Post New Topic  Post a Ford message board Reply
read DMs/my profile login | join CAFords | search | faq |
  next oldest topic   next newest topic
» Northern California Ford Owners     » Automotive   » Tech Talk   » Compression test on sitting engine

 - Email this post to someone!    
Author Topic: Compression test on sitting engine
z pyro
¯
Member # 3745

Ford Icon 1 posted      Profile for z pyro  Ford pictures for z pyro    Send New Direct Message       Edit/Delete Post   Reply With Quote       Share this CAFords post on FB
A compression test should work on a sitting engine, right? I tried a compression test on this engine I just got, and the gauge showed nothing. I did hear, however, air coming out either the intake manifold or the hole where the distributor goes. Did I get screwed on the engine that I thought was good?

Also, what size bolts do you use to put the engine on a stand? Cuz my engine just fell off the stand...I tried rotating it and it sheared the bolts right off. What size bolts, what strength, and where do they bolt to? I had 2 on the lower corners and 2 on two other places that the tranny bolts to. I used 3/8"x3 1/2" bolts that were threaded the whole length of the bolt. the two on the bottom corners sheared off (actually one did....the other had the engine hanging off of it, bent the bolt at about a 45* angle.) the other two just kinda fell out.

--------------------
'95 Integra LS
'08 Buell XB12R Firebolt
'65 Mustang 289 - soon to be 306

Posts: 1732 | From: Fresno, CA | Registered: Nov 2003  |  :
Stimson
_
Member # 51

Ford Icon 1 posted      Profile for Stimson  Ford pictures for Stimson    Send New Direct Message       Edit/Delete Post   Reply With Quote       Share this CAFords post on FB
Sounds like the piston wasn't at TDC. The intake valve was open and letting the air through. The piston has to be at TDC for the cylinder you're testing.
Posts: 2373 | Registered: Jun 2000  |  :
166 Merlo
FELONY
MOTORSPORTS
Member # 1549

Ford Icon 1 posted      Profile for 166 Merlo  Ford pictures for 166 Merlo    Send New Direct Message       Edit/Delete Post   Reply With Quote       Share this CAFords post on FB
7/16"

--------------------
'89 - Boss Coupe
'70 - Drop Cutthang
'68 - Cougnut
'87 - 0166, Its real

Posts: 3953 | From: Thebay | Registered: Jul 2002  |  :
mtbaughs
Road Racer
Member # 4052

Ford Icon 1 posted      Profile for mtbaughs  Ford pictures for mtbaughs    Send New Direct Message       Edit/Delete Post   Reply With Quote       Share this CAFords post on FB
Wow that sucks...Like mentioned you'll have to use 7/16 bolts to set the motor on an engine stand. As far as measuring the compression goes I would do the following to make sure it is a safe thing to do. Drop the long block into the car with the starter and tranny in place. After all the valve's are set/ roller rockers are set with proper pre-load I would than hook up a compression gauge. Using a remote starter switch spin the motor for each cylinder. This will give you the compression for each cylinder. Hopefully with the motor falling like it did you didn't damage anything. Not to sound like an ass here but you may want to grab someone who has some experience in doing this as I think it might save you some time and more importantly a lot of money if things end up going together wrong.

--------------------
R.I.P. Charlie Bruno Dec 2001

Posts: 2019 | From: Boise, Idaho | Registered: Jan 2004  |  :
z pyro
¯
Member # 3745

Ford Icon 1 posted      Profile for z pyro  Ford pictures for z pyro    Send New Direct Message       Edit/Delete Post   Reply With Quote       Share this CAFords post on FB
The problem with putting the engine in the car is I would have to take the engine out of the car that's already in it, then drop this one in, do the compression test, then swap it back out for the old one. and being my daily driver I don't have the time for that right now.

--------------------
'95 Integra LS
'08 Buell XB12R Firebolt
'65 Mustang 289 - soon to be 306

Posts: 1732 | From: Fresno, CA | Registered: Nov 2003  |  :
88-383
¯
Member # 4088

Ford Icon 1 posted      Profile for 88-383  Ford pictures for 88-383    Send New Direct Message       Edit/Delete Post   Reply With Quote       Share this CAFords post on FB
I may be with late with this info, but you can do a diffrential compression test on the engine out of the car.

Pull the rockers off so the valves stay closed then do a diffrential compression test. What you get is what you got! just let the piston settle at BDC becuse it wont matter. The chamber should be sealed.

Trust me this will work.

KM

Posts: 23 | From: Tracy | Registered: Feb 2004  |  :


 
Post New Topic  Post a Ford message board Reply Close Topic   Feature Topic   Move Topic   Delete Topic next oldest topic   next newest topic
 - Printer friendly view of this Ford topic
Hop To:

Questions/Requests/Suggestions? email CAFords



Fueled by Ford Mustang Owners
on CaliforniaFords.com