built motor leakdown test?

[4x4le]

I have a built sr that has never been started or ran. A potential buyer has asked me to do a leakdown test on it. No where near me rents the testers and the only place that sells them locally is harbor freight which has terrible reviews on theirs. I cant hardly see ordering one and paying over $100 for one that is decent considering in my opinion there is nothing to test.

Am I wrong one this? The engine has never been started, the rings have not seated and there is 0 break in. Wouldn't the results be odd considering this? I thought the leakdown would be for showing ring life/wear or cracks in the pistons. Am I the one missing something or is it the buyer?

Furthermore I am asking if it is even smart to put 100psi in the cylinders on a room temp engine without seated rings and a headgasket that has not seen heat.


Either way, tell me I'm smart, tell me I'm dumb ect. I am ignorant to this entire situation. All I have done is compression tests and boost leak tests in the past.

[Frank_Jaeger]

Buyer should be asking you to pull the head and pan, not for a leakdown test.

[4x4le]

Hah. Id do the pan but at some point i guess there is a leap of faith needing to be taken when buying 2nd hand. Im going to endoscope the bore

[jr_ss]

It's a catch 22. Your results are going to be bad with a leak down, but if you don't provide them he may back out. If you can prove that it's a 0 mile motor, what's the persons hesitation?

[4x4le]

It's a catch 22. Your results are going to be bad with a leak down, but if you don't provide them he may back out. If you can prove that it's a 0 mile motor, what's the persons hesitation?


See I have no idea. I figured one of us were ignorant to the situation but I didnt rule myself out as I personally have not performed leakdown tests.

Assuming something were wrong with the build of the motor it would most likely be tq procedure or clearances or something a leakdown isnt going to show.
I cant justify buying a tool so I can knowingly use it wrong.

The internals and accessories are worth what i am asking for the engine. This situation is frustrating

[hanzbrady]

It's a losing battle.

I recently lost a sale on my built SR because it only compression test 80PSI cold and 110PSI hot. All of this is due to it having a 7.0:1 cranking compression with 270* camshafts. It's actually dead on if you run the numbers in a cranking calculator but it still scares people.

[4x4le]

Exactly. There are so times when someone knows enough to be dangerous but does not actually understand what is going on that it ends up working against everyone.

I don't blame the potential buyer, its a reasonable request on the surface. He isnt answering my texts so I guess he isnt interested anymore.

[jr_ss]

Surely the motor still has assembly lube on the cams and crank correct? Photos showing that would help corroborate your claim.

[EnnEssEnnKAT]

I've got the harbor freight cheap one and it works fine. Good luck

[Karlhammer]

Just buy a decent tester. Its a good tool to have.

[anti tyler]

3 People from FL commented on this, possibly 4.

I would be cautious of this information.

[4x4le]

^^ do what?

[jr_ss]

^^ do what?

He's trying to make a Florida joke... However, he is from Florida too.

[jedi03]

just move on to the next buyer...that guy doesn't understand 0 miles ...

[4x4le]

He told me he is still interested the other day. It could be an honest mistake. I am taking video of it tonight with rhe endoscope to send him

[godrifttoday]

do you own a compressor ? and a compression tester? some have quick disconnect hoses, in which you can connect the hose to the spark plug hole and on the other end to your compressor. what i did was put 90 psi of air on the cylinders one by one and crank by hand, their will be a point in which you can crank anymore because of the pressure, it should not leak to any other cylinder, nor the valve