Being a back yard, shade tree wrencher, way in back yard and under big tree,

was wondering about pressure testing block by closing off thermostat outlet, pressurizing upper radiator hose and watching bleed down before reinstalling motor in car.

I have had an instance where put new heads and gaskets on my 1990 ej22 and found water spitting out exhuast and bubbling in radiator. Can this be used as a quick test to verify integrity of the repair??

Be nice to find out before going through all the labor of putting motor back in.

Pressurize to about 10-15 psi?? Should hold pressure indefinately, right?

Bad idea?

tnx

rick

w. mi

Pressurize to about 10-15 psi?? Should hold pressure indefinately, right? Bad idea?

It might be a useful test. Certainly if it bleeds down, assuming your t-stat outlet plugging and hose connections are tight, you've got a problem. However, keep in mind that cylinder pressure is about 10 times coolant pressure, and coming from the opposite direction, so this wouldn't be totally conclusive.

You could do it but I dont think it will tell you all that much. Conditions in a cold bench test wont even be close to a running, up to temp engine. Sure it could show you a major issue, but wont prove the integrity of the seal under normal conditions.

 

Gary

...keep in mind that cylinder pressure is about 10 times coolant pressure...

 

And thats just rotating static pressure, actually firing pressures are about 1000 times the coolant pressure.

 

Gary

tnx guys for the input.

Not sure now if it is worth the bother considering I would need to machine up some fittings and valves.

I guess if it was real valid it would be common practice.

rick

w mi.

And thats just rotating static pressure, actually firing pressures are about 1000 times the coolant pressure.

Good point; I guess I was thinking in terms of compression and doing a cylinder leakdown test, but even that might be difficult on a rebuild that hadn't been run in yet.