Paulyy

Driving home from a car meet, a coolant hose (the one that comes from the tube above the headers into the firewall) dumping the water out. i stopped at the nearest servo and filled up with water and had to drive 10 min home. in the 2 min it dumped all the water again, temp gauge on red. and around 1-2 min from home oil pressure dropped from 5 bar to 3 bar and loss of power.

We repaired the hose when i got back so it doesn't leak now.

Now each time i start it, it struggles to idle (sounds like it's stumbling) then it idles fine.

pulled the spark plugs, all black. compression tested it

last year while changing turbo:
1- 154
2- 145
3- 150
3- 145

Todays results

1- 125
2- 125
3- 125
4- 140

(both cold throttle open)

After i did that i opened the expansion tank and the water just exploded out (a lot of pressure in there)

so i get a pressure tester and put 18 psi in the cooling system and all i found was 1 old gasket leaking very slightly and a fitting from the turbo.


My theory so far is i've done the head gasket. Or if damaged the head and/or block. My dad doesn't think I've damaged anything but can't be to sure of that yet.

MooreBoost

damn that sucks man. hope its just the head gasket

Techno Duck

When it stumbles after start, immediately shut off and pull the plugs out. If they are wet, the headgasket is toast. You can also pull the plugs and look down in the cylinders, might see coolant pooling on top of the pistons.

blown 944

Probably HG. Use the hose from the compression tester and hook it to 100 psi of air pressure and watch for bubbles while goign through the fireing order.


It's weird that the compression is down on all cylinders.

I've overheated these engines in the past and they seem pretty resilient (non sleeved type)

Paulyy

me to!

well when i turned it on i didn't really let it idle i just turned it off. when i pulled the plugs they're all the same. black... didn't see much moisture, it was sooty.
I shined the torch down there, but didn't see much i'll have another peak again.

good idea. i've just adapted that to my compressor. about to do it.

I'm hoping it's nothing bad just the HG. i can deal with a cracked piston or something but doubt it's that. if the head is finished. easily replaceable.. but the block, well theres many options but to find one is a problem.

I'm hoping not!

s14kev

My bet is on the block being the issue. Head gasket I would expect greater variation between cylinders since one section on a single cylinder typically fails. Should see one very low reading and the remaining more normal.

Uniform overheating of the entire block can lead to ring wear/cylinder scoring and the lower figures you are seeing in multiple cylinders. Blown head gasket shouldn't drop oil pressure. Needs a leakdown test. I wouldn't run it without dropping the oil pan and checking bearings especially with the described drop in oil pressure.

Paulyy

Well the day after when i started it, it gained normal oil pressure back to 5+ bar.


So i tested cylinders 1 3 & 2. cylinder 1, the air just disappeared through the piston.. scored wall maybe?

cylinder 3 i had water poring out of the expansion tank.

Cylinder 2 blows out water also

number 4 i didn't bother with.

Thom

Time for some head work...

Paulyy

to look at it 1 way. The engine will be coming out as i need to change the oil pan gasket & clutch. which will happen in december so it's a few months.

So far i'm looking at these options:

if it's only the head gasket.. pistons & walls look good, i'll just do a bit of head work, possibly camshaft & custom intake.

If the HG is finished, cylinder walls are scored, i'll overbore 100.5mm or 101mm and get new pistons & rods. + above.

If the block is damaged (hope not) i'll go and build a 3L as a might as well and put my gtx3076r on it and either get the same standalone as yours if josh (rogue) cannot do a 3L map.

Rogue_Ant

Sorry to hear about the coolant/overheating.

3L map is no problem - and with the direct-tuning setup, there is near stand-alone tuning capability for the owner!

Paulyy

I'm just taking it on the chin i guess.

PM coming your way josh!

odurandina

damn.

i know it's water under the bridge, but hot is bad.

2 km from the house or 200 m should never influence what we do.

when a hose blows, that's zero coolant pressure.

gotta shut 'er off and limp home.



i always keep a half used up, creased roll of duct tape in the backpack with my cleaning products.

reno808

Sorry to hear paully that sucks. I got lucky when i blew my head gasket at the track. They seem to take the abuse. Maybe the gasket was already on the way out. Take the head off and get it done. I did mine in the middle of field with basic tools in a day. Drove the car back home 400miles. I actually drove it for a year before i decide to upgrade everything.

blown 944

If it is just the HG, I'd highly recommend using arp studs and a cometic gasket.

tman

+1, they have been good to me.