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quick35th
10-10-2005, 11:48 AM
Hey this may seem like a dumb question to most but I have never had to check the compression on an engine yet. So, my question is when checking compression should the oil pan be on the engine?

Shane

XR7inWI
10-10-2005, 12:34 PM
I would think having the oil pan on the engine would be a rather good idea. Without the oil pan you have no oil and I would not recomend cranking the engine to do compression test with no oil.

I am guessing that the engine is out of the car if you have the oil pan off, correct? If that IS the case, how do you plan to crank the engine with it on a stand, hanging from hoist, laying on floor.... whatever? :confused:

quick35th
10-10-2005, 12:58 PM
Yeah the 460 is not in the car yet and is on a stand. I had just planned on turning the crank by the crank bolt up front.

Shane

XR7inWI
10-10-2005, 01:06 PM
I don't think you will get very good results that way at all. What do you plan to use to turn the crank with? As far as I know, just turning it by hand with a wrench will not be fast enough to give accurate results. Hopefully someone else can jump in here and help out on this one but I doubt you can do compression test with engine on a stand.

Tracy

CrazyCouper
10-10-2005, 01:11 PM
instead of a compression test, do a leak down test.
the advantages are more accurate results, and you don't have to 'crank'
the engine to do it. Disadvantages are you need a reliable air supply and
a leak down tester.

bill

quick35th
10-10-2005, 01:16 PM
instead of a compression test, do a leak down test.
the advantages are more accurate results, and you don't have to 'crank'
the engine to do it. Disadvantages are you need a reliable air supply and
a leak down tester.

bill

Well I do have a really good air compressor so I think I have the reliable air supply thing down unless I need to buy a better regulator than the one thats on the compressor itself. How much do leak down testers usually cost?

Shane

CrazyCouper
10-10-2005, 06:03 PM
Here's a link from summit racing for a dual guage leakdown tester.
They have several this looked like the best one for the money to me.
Later,
Bill

http://store.summitracing.com/default.asp?Ntt=leakdown+tester&Ntk=KeywordSearch&DDS=1&searchinresults=false&N=0&target=egnsearch.asp