Leakdown test....help

[Mr GTiR]

Leakdown test

Can this be done without taking the head off the block?

If so will i need both the inlet and outlet manifolds on for the test?

Got a secondhand engine and need to do as many tests on it before buidling up and slining in the car.

What do people suggest? Compression test and turning over by hand is what i've got planned for it.

 

[Fusion Ed]

Compression test turning it over by hand will not really work unless your able to spin it as fast as the startermotor would. Also bear in mind that any open oil feeds etc, will want to pump oil over the floor, and you should really block them rather than catch it to allow the oil enough pressure to flow around the engine. However a true leakdown test will work fine, i.e. the kind that connects to a compressor, and can be done without having to do much else at all.

 

[Mr GTiR]

Thanks Edd, we will bolt up a starter motor and block all oil and water outlets off.

I take it that the missing inlet and exhaust manifolds will not affect the leakdown test?

 

[Fusion Ed]

Ed If your doing a leak down test you dont need to turn it over, if your doing a compression test you do - they are different. Another thing you can do is block off all the water ways and pressurise it SLOWLY to 40psi and then see if you get any leaks. This will check for any cracks in the block etc.

 

[Mr GTiR]

Thanks Edd, good suggestion.

Going to take the sump cover off and inspect the crank and bearings. Are the bolts that hold in the crank cradle strecth bolts?

 

[Fusion Ed]

No not that I'm aware of.

 

[stevepudney]

Thanks Edd, good suggestion.

Going to take the sump cover off and inspect the crank and bearings. Are the bolts that hold in the crank cradle strecth bolts?

Yes, they are !!

Andy, unless you plan on replacing the bottom end shells & bolts, and have all the necessary tools to reassemble it, I would leave well alone ( just thinking of your engine track record darling !!! ;-) )

 

[Fusion Ed]

Really? I stand corrected then.

 

[Mr GTiR]

LOL, thanks Steve.

Don't worry i'm only bolting the externals bits on this time but this replacement engine has been stood for a few months and just want to make sure it's ok before i bolt everything on and fit it in my car.

Might just get my mate to wip off the sump cover and do a visual inspection.

 

[Fast Guy]

Can this be done without taking the head off the block?

You might find you have trouble pressurising the cylinder to measure any leaks if you take the head off:lol: best to leave it onk:

 

[Mr GTiR]

i know this Carl bu the way i have seen a head done before is they bolted a big plate on the bottom of the head and did the leak down test that way. As i have already stated i did not want to split the engine apart.

 

[Dooie Pop Pop]

Thanks Edd

Ed

Thanks Edd

LMFAO!:roll: :roll: :lol:

 

[Mr GTiR]

LMFAO!:roll: :roll: :lol:

:doh: Sorry Ed

 

[AJ4]

i know this Carl bu the way i have seen a head done before is they bolted a big plate on the bottom of the head and did the leak down test that way. As i have already stated i did not want to split the engine apart.

leave the head on, turn it so both valves are shut and pressurise it through the spark plug hole, thats the way I know to do it.

 

[Fast Guy]

A leak down test is checking for leaks from the valves, piston rings and head gasket.

You can check the valves for sealing with the head off, but not the head gasket or rings.

 

[Mr GTiR]

Thanks for all your help guys. Will get it pressure tested within the week and let you know what happens.

 

[stevepudney]

Andy, check out the link ;-)

http://www.max-boost.co.uk/max-boost/Leakdown_tester.htm