Proper way to do a compression test??

[rcav8or]

Originally Posted by ALBUQ F-1

As far as I know all flatheads have rear sump oil pans, are you asking if it has the truck-style removable circular plate?

I would have to say my car flathead's sump is in the middle:



I am changing it to a truck, with the clean-out. But, my understanding of a sump, is the low spot, where the majority of the oil resides, that would make this a mid-sump, wouldn't it?

R

[jmadsen]

Roger,
That is exactly what my 8ba/eab has for an oil pan, I figured it was out of a car since the trucks would have the rear sump, plus the heads should say 8RT instead of 8BA ? I have been keeping an eye out for a rear sump pan for this engine, it seems like I saw a rear sump pan without the large cleanout (recently on the bay) . I would prefer to use one with the large cleanout though. hmmm
Josh

[rcav8or]

Josh - they can go fairly expensive, sometimes. Yes, I like the idea of the "originality" of the cleanout, but quite a few people have pointed out that they have a tendency to leak more than the one's without it. Since I am putting mine together myself, I will use plenty of "blue-goo", and make sure that it doesn't leak. If I wasn't going "original" and had access to one, the rear sump but without the cleanout, I'd probably go with it. I definitely would use the one out of the car, though. Looks ugly, I think...


R
See my bodywork HERE

[jmadsen]

Well I guess I would be just fine with the pan from the car (sump in the middle), but I thought I couldn't use it because it would hit the front axel or crossmember or something like that?? now I'm confused. would be for my 51 ford F1
Josh

[rcav8or]

I'm not sure about the clearance - I haven't tried it like it sits, in the truck. I've never heard of a clearance problem, but that's not saying anything - but I have heard of car motor's in the trucks - in fact, my truck had a car motor in it, when I got it. Had been rebuilt once, too...

I'm sure someone will pipe up about any clearance problems - if you get to that point, it wouldn't be hard to set the motor/tranny in, and see. Maybe save a few bucks, if it works - your's is going to be a daily driver, right?

R

[hamz52]

I just went and looked and the center sump looks like it could possibly present clearance problems if you hit a bump large enough. Looks like it would be the tie rod that would be in harms way.

[brucelee]

On the compression test, I use a remote starter button (a simple hand held device with a couple jumper wires hooked to the starter solenoid). This way I can watch the compression guage as the engine rotates noting how the pressure build during each cycle. I know that the cylinder has reached its highest pressure plus get an idea how tight the seal is by monitoring how quickly the guage jumps on each compression stroke. For further testing I use a cylinder leak down guage which can help pinpoint leaks in either the intake, exhaust or rings.