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a leakdown test tells you if everything is sealing right,if not you can usually hear if its leaking from the intake or exhaust or things like bubbles in the coolant is a bad head gasket air comming out the dipstick and such would most likley be rings.All you do is put the cylinder you want at TDC on compression and use a leakdown tester hooked up to an air line and fill the cylinder with air pressure,so kinda like compression i guess,this just tells you where you are losing compression.
 

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A leakdown test is done just like a compression test...

You just use shop air to pressurize the cylinder.

I would take it to someone, because there is a possibility of damage to the head gaskets, if done wrong, with too much pressure.

It's basically a fitting with an air valve, and a pressure gauge, that screws into a spark plug hole.

If there is a leak, it won't hold pressure; bubbles or water pouring out the radiator fill mean a bad head gasket, for example...
 

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No shop comressor will damage a head gasket. A compression stroke alone will be more pressure than a shop compresor.

Justin is correct in bringing the crankshaft to TDC but it must be exactly TDC. A few degrees off and the piston will go down as soon as you introduce pressure into the cylinder being tested.

Another reason leak down is prefered over a compression test is you will know how much you are leaking.

A tester has 2 gauges. One is the inlet pressure and the other is the pressure in the cylinder. If you have 100psi on the inlet and 95psi in the cylinder. Then you have 5% leak. Which is good BTW.

 

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Discussion Starter · #5 ·
Well I did do a compression test. The resaults are depressing


1.100 Psi
2. 142 Psi
3. 27 Psi
4. 48 Psi
5. 190 Psi
6. 160 Psi
7. 160 Psi
8. 190 Psi
 

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95tbirdguy said:
Well I did do a compression test. The resaults are depressing


1.100 Psi
2. 142 Psi
3. 27 Psi
4. 48 Psi
5. 190 Psi
6. 160 Psi
7. 160 Psi
8. 190 Psi
one bank (drivers side) looks fine but the other (passenger side) looks horrible. my guess is a blown head gasket, but you won't know until you investigate further. leak down test is definetly a good idea.
 

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Discussion Starter · #9 ·
Bad head gasket wouldn't cause oil in my intake tube though and there is no coolant loss at all. I am thinking rings. And when I removed the #4 plug my socket and the plug was coveed in oil!
 

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I blew it on the HG thing; you are totally correct; downstroke pressure is thousands of psi...

I saw the previous post about the oil; that's the way my firebird looked, after three broken rings, at 60k miles...

My last compression test on my red car was great, (I don't remember the numbers) at 160k miles. These engines rule, but do eventually break, tho...

How many miles do you have on it? I'm at 196k on the red cougar, now, still runs great, but needs a tranny...(and not the eddie murphy kind)
 

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Bummer...

So, did you have something catastrophic happen?

A hydrolock, lean burn, or other major prob is indicated here;

Can you go back to the guy who rebuilt it for you, or otherwise get a warranty replacement?

I realize how much it has cost you so far, if the engine is new, as I've been pricing such things...That sux.

If it's your baby, it's time to bite the bullet, and take it out, and take the heads off.

If there's a warranty, follow it to the letter; people take any excuse not to honor things these days.

Take lots of pics, or an uncut video of it being disassembled, for proof, if you are going to need proof of the problem. Two camcorders, running in overlapping fashion, can give convincing evidence to a court, if you have to sue somebody.

Better is to take it to someone you trust, who will swear in court that the damage was caused by the provider of the engine. (that is, if it really wasn't your doing...Nitrous burnouts on an un-broken-in engine isn't their fault, not that I think you would do anything like that, just an example...)
 

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You don't think it overheated or anything and burned the piston rings, do you? Does it smoke really bad? I find it hard to have 4 burnt piston rings on one side of the engine, but I guess it can happen. It would have to be blowing out oil smoke out the back if you have that many burnt piston rings. Does it miss real bad upon cranking it in the morning or anything until you rev it up and clear it out?
 

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I think you guys may be missing something -- The problem is associated with an entire bank. I doubt he fried rings on 4 cylinders at the same time, and left the other side intact. The fact that there was oil present also tends to defy that.

Check your cam timing.

EDIT: Typo - Thanks Melon ;)
 

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Can you actually break a piston with the valves??

A holy piston would certainly account for the oil, but I think ANYONE could hear the noise that had to precede that...

I guess you could put the head gasket in wrong, so that an oil passage connects to the cylinder...

I really cannot see the valves taking out a ring, so that it didn't make some incredible noises...

Maybe they just left off the rings from one side!! (total drag, but easier to fix!)
 

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Discussion Starter · #16 ·
It runs like crap. It barely idles and when it starts too warm up it won't idle at all it just dies. The reman company seems to think that I might have a bad head.
 

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Did they sell you the head? If it was a long block engine, a bad head is still their problem.

I've seen a bunch of cracked heads; ford 2300 4 cylinder engines are almost always cracked in the boneyards...

I've never seen a crack that would drop 4 cylinders at the same time...and still run.

Your oil; is it full of water? I believe a crack that would take out the whole bank would HAVE to leak into the water jacket.

I've also never heard of these heads cracking, either... blown manifolds, head gaskets, yeah, but... (I have been wrong before, if so this time I'm sure someone will chime in...:tongue: )

Hopefully some doofus left out half the rings.

If they wont stand by it, I'd tear down the engine, if front of witnesses, on video, and send them the result. The video, as long as there are no cuts, can stand as evidence in small claims court; The bad publicity from being shamed here and elsewhere will cost them much more than sending you another rebuilt engine. the video also protects you should they sue you for 'besmirching their good name', should that ever come up.

You should have a good mech do the disassembly If you are unsure about your abilities; you will be on video taking the engine apart, and any '******* engineering' moves are cause for them to deny your claim.

If the video shows they gave you a bad engine, small claims court here is good for $5k, enough for a new engine.

Good luck; I hope you will post pics, and name the company...

If you know you blew it up, I'd just suck it up, and start saving; absent a bonehead assembly job on their part, it will be hard to prove its their fault for certain.

If you assembled it from a short block, there is a lot that can go wrong; a lean condition from a leak on that intake can burn all the pistons up at the same time...and especially the two middle ones, in a short time.

What codes did it throw at the beginning of the mess?
 

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Discussion Starter · #18 ·
Well I finally got a leakdown test done. 85% leak. Excessive Blowby past cylinder and piston out breather tube into air filter housing. BAD RINGS!! Just as I thought.
 
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