4M40 Problem Solved, i think

[joshua.alexander]

Hi folks, just heads up, my car is repaired, i think,i thought i cracked my head, did exhaust gas test, cylinder and rad compression test every cylinder was reading 200psi at crank speed, only good results; before i took my car to the shop it was over heating every 150kms, there was bubbles in rad and overflow was full, i got rad rebuilt, new water pump , new cap and thermo, cost $750, i dont see bubbles anymore so i hope it has fixed the problem, thanks to all who have helped from my last thread

[Thomas101]

Gday,

Sorry to bring it up, but you're sure the 200psi is correct. Mine returned 400psi. Anyone got any thoughts?

Thomas

[joshua.alexander]

i dont no, i think i got a bit to cockey, it will over heat again i know it, the coolant is going to the overflow and not returning, but there are no bubbles in the radiator, i left my overflow bottle to full (halfway), after driving it, i noticed that the hole bottle was full! when the car was turned off, any thoughts on that?

[Mitsi Lover]

i dont no, i think i got a bit to cockey, it will over heat again i know it, the coolant is going to the overflow and not returning, but there are no bubbles in the radiator, i left my overflow bottle to full (halfway), after driving it, i noticed that the hole bottle was full! when the car was turned off, any thoughts on that?

The cooant expands into the expansion tank when hot and the radiator draws it back as it cools.

200 psi is too low for a diesel engine.

[MTN-KAT]

Hi joshua, I suspect you have a cracked head or blown head gasket. The compression is finding it's way into cooling system and vents itself out overflow. Even a small crack will behave this way. Your original thread indicates an overheating issue. Probably caused by a leaking water pump. If you refill hot system with cool water this is often the result. Happened to my sister in laws Isuzu. Even waiting a few hours to refill was too soon. Should have let it get cold overnight. I've heard of a thing called engine lock? I think that's the term. Happens if water gets in a cylinder which can't be compressed, particularly in a high compression motor like the diesel. Can do severe engine damage. Wish I didn't see it this way and hope I am proven wrong for your sake but it has to be considered. Cheers.

[joshua.alexander]

Hi, i really dont understand, maybe the compression is low, but it has a shitload of power, i dont understand how its the head, or head gasket, i have had a cyclinder compression check, radiator compression check and exhaust gas test, i got a brand new head fitted 16 months ago.
''The cooant expands into the expansion tank when hot and the radiator draws it back as it cools.'', how much coolant expands tho and i let the car cool and nothing, i suspect the car will overheat whenall the coolant expands into the overflow bottle and overflows out of it.
the diesel mechanic said it was 200psi at idle

[MTN-KAT]

Maybe not head or gasket. I was just saying how similar it sounded to my sister in laws case. All tests are hopeful. Have you checked radiator full when cold in morning? Seems excessive to find overflow bottle fills up when hot and equally odd to find it empty when cold. Would not expect that much fluid from expansion. No doubt you will be monitoring its behaviour on a daily basis till you know whats going on. Cheers

[joshua.alexander]

Well i will be monitoring the rad i will check in morning, i appreciate your thoughts and comments but i just cant see it as a head or gasket, tthere are no symptoms lol, but thanks anywY

[Matatak]

How old is the Radiator Cap? if thats buggered it wont return the water back into the system whent he car cools down.

Who did the compression check? 200Psi is way to low for a diesel.

[Mitsi Lover]

Just checked my Haynes manual.

Compression Pressure
2.8 L
Standard 2,640 kPa
Minimium 2,250 kPa
Max Variation 290 kPa

Divide these figures by 6.895 to get a conversion to psi.

[joshua.alexander]

Yeh i am with ya there, either the mech didnt do it right or i am looking at getting new rings, but the water returned to the rad this morning so thats a positive, but if i need new rings atleast a get a new head gasket out of it haha

[REDNUT]

its it overflowing the overflow bottle, maybe try to poke the overflow hose off that bottle straight out your grill, then if it does happen to dump out the overflow bottle you will know really fast,

mine fills the bottle after a drive, then takes a while to suck back down to the max line

[joshua.alexander]

So what do you mean , "try to poke the overflow hose off that bottle straight out your grill" sorry , dont understand

[REDNUT]

well there are 2 hoses that go to your overflow bottle, one from the radiator, another that enters the overflow bottle beside the one from the radiator, vents straight down in front of the bottle, take that hose that points down and move it so if it does dump its water ( or steam ) u will see it, might just need to give the front a good was, maybe a polish if it does dump everything

[joshua.alexander]

ok, thanks for your help, but it wont help whilst i am driving, at the moment the coolant has seem to be staying in between the lines but i ddont see any coolant in the radiator