Baz

93 1.6 FMII hardware

When I fit my built engine I want to make sure I have no boost leaks, I have made a boost leak tester and tested it to 25 psi and the tester holds pressure no problem.

I am happy testing the IC pipe work from the turbo outlet to the inlet manifold, but I have read on other car forums that they test the complete intake system by attaching the tester to the turbo inlet and pressurising the whole system slightly above your required boost PSI.

I was just wondering if anyone has done this and has any advice ie can this cause any damage to the turbo seals or anything else on the engine?

All advice appreciated......
Barry

Faeflora

iTrader: (2)

Entire stupid intake stupid.

From compressor inlet onwards

Also test to 50psi because ut is easier to hear leak and u will find future failure spots more easily.

Baz

Thanks for the info........

triple88a

iTrader: (2)

What do u want?

Baz

Is that directed at me?

triple88a

iTrader: (2)

No the persons msg got deleted. Scammer i believe.

Baz

Oh OK, this full boost test has me baffled, surely all the compressed air will rush out of the open exhaust valves? I have tested the inlet pipe work from turbo outlet to TB and its holding 30psi so thats ok, but i really want to test the inlet manifold as well....Confused........

Barry

triple88a

iTrader: (2)

Well there's a chance that you'll test on an overlap angle but from memory there isnt much on stock cams.

Baz

Thanks for that, so get #1 cylinder at tdc before doing the test?
Barry

JasonC SBB

What's the risk of 50 psi busting your i/c?

mighty mouse

iTrader: (9)

unless you are going to run 30psi, why would you bother testing that high?

Baz

Far better to test at a higher pressure than you will be running, any potential issues will show.....

Baz

Does anyone have an answer to this:

do you put #1 cylinder at tdc before doing the full intake boost leak test?

Barry

triple88a

iTrader: (2)

I'd imagine a bit before or a bit after. At TDC the intake valve will be opening and exhaust valve closing.

Baz

Cheers bud, appreciate the advice.....

Savington

iTrader: (31)

I'm 99% sure that you can't do a 'full-intake' boost test without unbolting the intake cam, since at least one cylinder is going to have the intake valves open regardless of where you have the crankshaft sitting.

Test IC pipes from the throttle body coupler to the compressor inlet. If you think you have an intake manifold leak, test it with ether, starting fluid, propane, or the smoke from a cigarette. All of that is way, way easier than opening the valve cover, unbolting a cam gear, and unbolting all the cam caps.

JasonC SBB

Just seal the exhaust pipe with a banana.

triple88a

iTrader: (2)

Right but the exhaust valve should be closed so it still wont leak.

Faeflora

iTrader: (2)

Look just hook the damn thing up

Forget all the valve tDC bullshiz.

Just pressurize the motherfukker and you will hear leaks. Yes air will go past valves but that is ok.

you will still find leaks.

Sheesh

Savington

iTrader: (31)

Then you're just doing a leakdown test though, and unless his motor has perfect leakdown (doubt it) it defeats the entire purpose of a boost pipe test.