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Also i just remembered now that when i was doing the boost leak test, @10psi oil dipstick popped out and released all the pressure which seems bit odd on such low pressure.

Forgot to take a picture but here's a picture from Google how i did the pressure test:

Getting blow by on the rings. If motor was cold then could be nothing. You'd have to comp test a warm motor to see though.

Thanks for replying.

Engine was warm when i did it. Getting a compression tester from ebay but i hope you're wrong mate, wouldn't want to pull motor apart at the moment.

Edited by GhostK

Get a leak down tester and check it properly.

DO NOT by a ebay leak down tester...i did and spent a whole evening modding it to work properly.

They are suppose to have a 1mm orifice to work correctly, the ebay one didn't and i had to make one to get the right readings.

At the moment i just bought the compression tester but you're right, none of the leak testers on ebay doesn't seem to have orifice on. Did you filled the middle pipe with epoxy or something and drilled the 1mm hole through ?

Removed the inlet hose, cut a thread into the passage, drilled a 1mm hole in a grub screw and loctited it in.

I also pissed off the % gauge and used a normal 100Psi gauge.

95Psi reading when its set at 100Psi translates to 5% leak down

If your compressor wont go to 100Psi, do the test at 50Psi and double the resulting pressure decrease to calculate the true percentage.

So if you test at 50 PSI and the gauge reads 45Psi, your 5Psi drop means a 10% leak down.

Righto, thanks.

Compression test should show if there is something dodgy going on and then i would have to rebuild the engine anyway but if it doesn't I'll get a leak down tester.

Yeah i know it's me again....

Anyway, got the compression tester today and here's why I've been getting mashed by Fords lately.

Cold, dry test

1) 135 psi

2) 50 psi

3) 150 psi

4) 140 psi

5) 135 psi

6) 135 psi

Cold, wet (teaspoon of oil) test

1) 168 psi

2) 90 psi

3) 200 psi

4) 180 psi

5) 178 psi

6) 178 psi

Not sure if to go and buy a carton of bundy or start pulling the motor apart... on a side of the street coz don't have a garage or not even enough room in a yard for a car.

I reckon it's too much of a difference between cyl 3 and all the others too.

If i already have to do the job i might as well get a whole rod and pistons kit, just don't know yet what size to take as that engine was already swapped with original one 2 years ago and not sure if any internal work was done back then or no.

I've got 3 or 4 used OEM pistons (had at least 2 with broken ringlands, would have to check the rest) if you want a cheap option. Also have a brand new set of OEM rings in stock size - bought then decided to buy forged pistons.

Thanks heaps mate, i just lost my long term job today so everything is going pretty bad for me lately...

You wanna pm me the price you would take for the pistons/rings you have there ?

  • 1 month later...

Been exactly month now since last post, finally i got a house with a good size yard so i pulled the motor apart.

Cylinder 2 piston that gave me 50psi (dry)

post-140925-0-74269100-1444469491_thumb.jpg

post-140925-0-61054600-1444469510_thumb.jpg

If i started taking the rings off Cyl 1 and 6 piston ringlands gave up too.

post-140925-0-44310000-1444469530_thumb.jpg

Luckily I got 3 spare OEM used pistons witch gives me a good set of 6 all together + new OEM ring set.

But I'm bit concerned now if i'm already spending that much money to freshen up the head and the block(head is already in engineering shop) and finally decide to aim 250-300rwkw I might end up with another broken ringland ?

So you're now in the same position we were earlier in the year - 2 pistons with cracked ringlands, motor in bits, how far to go (how much to spend). We bought oversize forged pistons and had the block bored to suit, but it added close to $1500 to the build cost - the bores had already been honed to refit the stock pistons and had to go back in for the rebore. This was why I had a new set of OEM rings. It will be more a financial decision than anything. Not sure if your mentioned earlier in the thread, but what are you using the car for? Ours is a track car so spends a lot of time working hard - this is what pushed us towards forged pistons.

It's just gonna be a street car, no track days whatsoever.

What caused these broken ringlands I reckon was a very bad tune in bad hands of previous owners. If i got that car it had a hole in a pod filter, O2 sensor not connected, different spark plugs in every cylinder, very low engine oil + very dirty oil, blocked breather hoses, vacuum leaks, thermostat drilled through so engine never ever warmed up etc etc.

So IF i decide to put it back together with these old pistons hopefully i find a good tuner(hard to find up here) after installing power FC and it SHOULD last but yeah...

Also depends what the bloke in engineering shop reckons next week when i show him the bottom part of that motor.

Oh and by the way the pistons i got from you went clean in heavy duty degreaser in 20 minutes. :wave:

In a meanwhile, the pistons from my engine been soaking for 12 hours and only the sides are clean...

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