scoobyc

iTrader: (2)

Just got back after a not too harsh burn around, with about 5 min of antilag (my new toy).

after a 10 min cool down i pulled up home and started steaming out engine.

Expansion tank cap has done its job and is venting. Looks like the water has got too hot.

However the oil temp is a nice 85 and water temp is dead in the middle as normal.

This ring any bells with anyone? Clearly i would contribute this to antilag causing too much temperature boiling the water. But had a very good stint yesterday without this issue.

All advice welcome.

Cheers
CHris

The Rig

iTrader: (13)

hmm,maybe the water temp sensor for the dial on the dash wont read higher than halfway,whatever resistance that is etc ????

scoobyc

iTrader: (2)

hmm perhaps. Where bouts is the sensor located?

The Rig

iTrader: (13)

its next to the coolant temp sensor for the ECU,in the alloy piping under the inlet manifold on the drivers side,it has just the 1 wire going to it,the other with the 2 wire plug is the coolant temp sensor for the ECU/cold start etc

scoobyc

iTrader: (2)

And wouldnt the oil temp also increase?

Turbotits

iTrader: (2)

perhaps the temp is good and the cap is releasing to quick

The Rig

iTrader: (13)

not sure,oil takes longer to boil than water but if a thermostat is blocked shut so the water is just circulating round the block that will heat up alot quicker than the oil as thats flowing thru the sump etc

scoobyc

iTrader: (2)

true. will investigate further on weekend.. will look in the morning and see what the levels are at and see if its usable for work.

To be fair the coolant looks like it could do with a change..

scoobyc

iTrader: (2)

Ok Plot thickens after some quick investigation.

Refilled the expansion tank and the other filler this morning. Warmed car up and used heater. rechecked fluids and all ok.

Drove for about 1 mile, lots a steam. I assumed burning off water on zaust. Pulled over and no sign of water escaping the expansion cap. However i felt the tank and it felt like the water was boiling...

Drover further to work, had some squeeling sounds from what i think are the belts. however it could be hissing from pressure release.

Lots more steam.... really slow drive. Got to work popped the hood, and i could see fresh signs of water from the expansion tank.

Again all temperatures are rock solid.


I notice there is a water pipe to the turbo. That would account for last nights boilage, antilag got turbo too hot and boiled the water. However not this mornings.

Also the engine sounds different. I cant describe how it just sounds more throbbing..

I will check levels tonight and see if anything needs topping up. could be just extra water boiling off. Rad pipes both felt super hot so assume rad is working.


Things to note. Just had first remap, with ALS, and using a turbo blanket. Also old coolant. It needs a change..

Advice welcome. Hope these arent signs of something major like head gasket or piston???

JDM_Stig

iTrader: (3)

What age car/miles etc, sorry but it does sound like a head gasket esp after a remap if u have seriously up`d the boost etc,
Was the remap for FMIC or just a tweek? (had you been running it on any mods before the map)

scoobyc

iTrader: (2)

98 STI 70k

3" decat & panel filter pre-remap. std tmic running 298.1 bhp. Its been running fine (i.e. no boiling) like this for the past 8 months or so.

Post map making 1.4 bar, pre-re-map making around 16psi-21psi

Yes the more i read the more it sounds like head gasket. I best get AA tow it home on a flat bed, dont wanna warp the heads!

not good.

53

iTrader: (41)

Muchous Antilag will test the cooling system and find the weak points. My header tank died, replaced with Forge, rad died, replaced with alloy rad and Zerosports Thermostat opening @71dg. Get a coolant change and new thermostat for piece of mind. Be prepared to change other parts depending on age. The plastic header tanks and rad tanks when old won't like the added pressure.

scoobyc

iTrader: (2)

Just to be on the safe side i best get the car towed back home.

Is it ok to Tow a scoob with all 4 wheels on the floor. or is it flatbed only?

mikey30

flatbed only mate!!!!!

scoobyc

iTrader: (2)

Ok time to get inspect... then call AA. they might arrive by the time i finish work at 7pm.

Any conclusive tests to detmine HG failure?

JDM_Stig

iTrader: (3)

You can tow it with all 4 wheels on the road fella, its when 2 arent moving you can have issues,
You could get a block tester kit tests for hydrocarbons or something in the coolant

scoobyc

iTrader: (2)

Ok thought so.

Think ive found the issue. Went to look on lunch break. Put in 4l of water. Ran the engine for a little bit and no steam. Then decided to rev at 3k rpm and straight away steam..

I was thinking wtf?

back to idle jump out and couldnt see anything where the steam was coming from.

Reved it with my hand and started getting spattered with water. Again no leak from expansion or hoses. Followed the splashes from the power sterring pump pully. To the left is a rad hose with has a pin sized hole which only opens above 3krpm spewing water onto the pulley!

I think this is the cause for loss of pressure! Its not really accessible, and i dont have any tools on me so pre2k rpm crawl home is on the books i think keeping it topped up to max.

Im assuming any pressure loss like this can cause the water to boil? Does this sound like the likley cause? i REALLY hope that this hole hasnt caused engine to overheat and do the gaskets anyway....

JDM_Stig

iTrader: (3)

Or it could be the HG failing and the added pressure on the system thats popped the hose?
Be nice if it was a cheap fix though.

53

iTrader: (41)

I also have uprated samco rad pipes !

scoobyc

iTrader: (2)

Yeah lets hope so mate! Was looking forward to a spannerless weekend. never mind!

scoobyc

iTrader: (2)

Samco want 150 bloody quid for the hoses! they made of gold or summat!

scoobyc

iTrader: (2)

Replaced with Samco pipes, filled with blue coolant 50 50 mix.

Seems to be ok! Took it for a good blast and no overheating or boiling or steam or whatever.

Think its fixed! PHEW!!!!!

Thanks guys for all the advice. I was gearing myself up for an engine out next weekend lol!

STI_Baly

iTrader: (23)

Just read this from top to bottom, lucky escape (touch wood). As suggested above if you have a plastic header tank change it for the later uprated metal version.

scoobyc

iTrader: (2)

Its a metal tank. and looks ok.

The water which came out was utter crap. it looked very RUSTY!

Ive read thats sign of HG gone too.

Also my different engine noise turned out to be the exhaust note bouncing off the house opposite. cover zaust and it sounds sweet.

So any comments for the rusty looking coolant? Age since it was last changed? Rusty Rad? Turbo on its way out? HG?

Car pulls fine..

STI_Baly

iTrader: (23)

Good to hear, the rusty residue is usually down to wrong types of coolant used over the years and the HG's and RAD cr ap accumalating over the years..Hopefully HG's and turbo seals are OK..

I advise that you flush it all with a Aluminium friendly flush and then use some performance coolant. Read the instructions on whatever you use as some require that you only use de-ionised water to dilute the coolant and some only require 25% of de-ionised water.

scoobyc

iTrader: (2)

Yeah it all got a very throurough flushing through untill clear.

Im sure the stuff thats in it now willl be good enough. Will double check SH for when it was supposedly last done.