angela_itr

Ok I've just done 300 miles in my ITR today. I was cruising at a steady 80mph for about 30 miles on my way home, all was well with the car. Then a Mazda starting harassing me in the fast lane so I floored the throttle and took it up to about 130mph just to show him what he was messing with Point made, I went back to 80mph for a few miles, before pulling in to fill up with petrol.

After leaving the station, I pulled up for 30 secs to get a drink. When I got back in, the temp gauge was halfway between normal and hot. I quickly put the heaters on full and the temp came back down to normal so I carried on driving. I figured maybe it was heat soak and it would eventually cool down if I took it steady and kept the heaters on?

Anyway all the rest of the way home (100 miles or so) I stuck to 80mph but the temps would sometimes go above the midway point if I didn't keep the heaters on. Its been a fairly hot day today but I've never had a problem with it overheating before, except the couple of times when I've had coolant leaks. Its an 84mm sleeved B18C6, stock ITR rad (full size) with 2 fans, FMIC.

Yesterday the cambelt was changed, might this be relevant? I drove 50 miles home afterwards and temps were fine even after 5th gear boosting. We noticed a lot of condensation in the valve cover. I have a breather for the valve cover but its not under vacuum so don't know how useful it is. I'll be getting a proper catch can setup soon.

I've had coolant leaks recently, from bottom rad hose and rad cap (both now replaced) but it also seems to be spraying out of the reservoir bottle cap. Because of this, we over-filled the coolant yesterday. When I checked it after the overheating today, the reservoir was full to the brim. Is it bad if this is too full?

Baffled really, I've done 4000 miles since the engine was built and its never overheated like this before

B18C1CYA

sounds like a sleeve problem or a blown head gasket

lucidvtec

i would say a blown HG....does the colant resv
bubble??

angela_itr

Didn't notice it bubbling when we topped up the coolant yesterday. Would a blown h/g explain the condensation/oil mix on the inside of the valve cover?

It was ok last night, and I was driving it pretty much the same, took it up to 130 a few times. So one 5th gear pull today might've blown the h/g? What other symptoms - do a compression test?

meanEG

you probably have an air pocket in the system somewhere. snap-on makes a bitching tool that applied vacuum to the whole system thought the cap hole, then sucks coolant in froma bottle.

try jacking up the front of the car and running it for a while to see if it drops iin level. also are the fans working?

angela_itr

Yep fans are definitely working. The coolant system was flushed and refilled a month or so ago, but since then the rad cap was still leaking so I've had to keep topping it up regularly.

So hopefully an airlock in the system rather than h/g..

Any more thoughts? What about the reservoir being full right up, when the water gets hot, it has nowhere to go?


Modified by angela_itr at 10:07 AM 8/29/2005

meanEG

if that is the case the car is probably bad.

wtfman2

Filling the reservoir to full will just cause the coolant to be pushed out till it is the correct leval again and isn't a problem. If you ae seeing condensation in the valve cover I would suspect a head gasket or possibly a sleave problem unfortunatly. They also sell a tool that screws on the the rad cap and pressurizes the cooling system and you then listen for air the see where it is coming from. You pull the spark plugs to here for a gasket leak and also the coolant needs to be drained for this test also. But first things first. Are you sure that you got all of the air pockets out of the system, there should be a little bleeder on the thermostadt housing.

Clinton

meanEG

i mean cap not car

Adi Radoncic

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by angela_itr &raquo;</TD></TR><TR><TD CLASS="quote">Would a blown h/g explain the condensation/oil mix on the inside of the valve cover? </TD></TR></TABLE>

Yes, air pockets don't cause that milky looking substance on the inside of the valve cover, if you wanna do anything have a shop do a leakdown test. But its most likely your headgasket.

Suprdave

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by angela_itr &raquo;</TD></TR><TR><TD CLASS="quote">Would a blown h/g explain the condensation/oil mix on the inside of the valve cover?
</TD></TR></TABLE>

Uhm, yes hahaha....

meanEG

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Suprdave &raquo;</TD></TR><TR><TD CLASS="quote">

Uhm, yes hahaha....</TD></TR></TABLE>

oh yea, i didnt see that part.

SOHC_MShue

sounds most definitely like a headgasket or something of that nature.

angela_itr

Yeah I think so too Its overheating again today, which is no surprise but I was kinda hoping it was just yesterdays heat. Also the heater started blowing cold air today despite the temps being hot, which is a classic sign of h/g failure I think?

Haven't lost any more coolant, but have lost oil since the last change 1500 miles ago. Its gone from being on the top mark on the dipstick to just below halfway down. Haven't noticed the car smoking tho, and not aware of any leaks so don't know where its going.

When my cambelt was done yesterday, they pointed out the nasty stuff on the valve cover but said it might be just condensation building up due to a poor breather system, and said we'd check it again when my catch can arrives. I guess he was just trying to save me the bad news

Wonder when the h/g blew then... Obviously yesterdays blast brought the overheating symptoms on, but it must've already been leaking before. I've been driving the car pretty hard lately, might it be worse than just a h/g or should I be ok for as long as the temps were ok?

SOHC_MShue

Has your car been tuned? Too much ignition timing can easily pop a headgasket espescially if you are doing high gear pulls.

200cs

A defective radiator cap can cause overheating problems. The cap is designed to keep the coolant under pressure. If it does not, then it will leak out and run warm. I had a Volvo do the same thing. I replaced the cap and the problem went away.

As far as the condensation in the valve cover, you may have a problem. I know it is not unheard of to have condensation in high humidity areas. I had a friend with a boat that was doing the same thing when it was humid but on a dry day, it would not. I would suggest testing the compression and the cooling system for abnormalities before anything is torn apart. It may be as simple as a defective cap causing the car to run warm and the extra warmth causing condensation in humid weather. Good luck!

angela_itr

The car was tuned by Mase in July, runs great and I have faith in him, its not a tuning issue

I did have a faulty rad cap which caused overheating about a month ago, as I was losing a lot of coolant. It was also leaking from the bottom rad hose. So a couple of times the car got really hot. Maybe this was when the damage was done? We changed the rad cap and hose, flushed the system and filled back up with coolant, and its been fine ever since... until yesterday. I've done plenty of 5th gear pulls, tho admittedly yesterday was a hotter day than usual.

Anyways, will check the coolant system out again first before drastic action.. fingers crossed!

angela_itr

Well I drove to the workshop to get my Teg checked over today, and ended up hitting a major traffic jam, 2.5 hours on one of the hottest days this summer I sat with the heaters on full the whole time just incase - I nearly boiled to death, but the car was fine and didn't overheat at all. I'd topped up with water this morning, and although the overflow bottle showed the coolant level was ok, the rad actually took 1.5 litres!

So we checked the coolant system, the pressure in the system increased as the engine revs were increased... so possibly h/g problem. But then we did a leak down test, and there was no leakage across any of the cylinders But its obviously losing coolant from somewhere. So thoughts now are that the rad is faulty, possibly blocked - leading to pressure in the system which forces water out of the overflow and leads to it overheating. Sound reasonable?

95rippinrs

could be a crack in the head casting

Muckman

iTrader: (2)

Sorry thats not likely. You have classic signs of a blown head gasket. Its not the end of the world.

angela_itr

If it was the head gasket, it would show on the leakdown test surely? Otherwise whats the point doing it!

200cs

there is a test you can do to check for combustion gasses in the cooling system. It is made by Lisle Tools, part number 75500. It costs about 30 US Dollars. I would suggest trying that to get a better idea of the problem.

As of right now, it sounds like a crack in the block or head that only opens up during compression. A coolant system check generally only puts in about 10 psi which is considerably less than your engine produces during the compression cycle. And, a cooling system check is done while cold. An engine at normal operating temperature could cause the crack to open as metal expands when hot.

Good luck and keep us informed.

edit: I read back over and was shocked at my mis-spelled words. I hope none of my former professors read it!


Modified by 200cs at 12:36 PM 8/31/2005

turbosi03

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by angela_itr &raquo;</TD></TR><TR><TD CLASS="quote">If it was the head gasket, it would show on the leakdown test surely? Otherwise whats the point doing it!</TD></TR></TABLE>

leak down test is very usefull but it does not tell you if your gasket is leaking when engine is hot. its possible you have a hair line gap in the HG between a cylinder and coolant passage. this will only push exhaust gas from cylinder into the coolant when under boost or maybe just when its hot...

Edit:
200cs and I are on the same page I think he's talking about a hydro-carbon tester... great idea! 200cs, thanks for the info on how to get one

Muckman

iTrader: (2)

Unfortunately leakdown and compression tests do not always show blown head gaskets because the pressure of a actual live combustion chamber cannot be simulated with a few PSI from a compressor.

angela_itr

ho hummm... ok so inconclusive then. Well have ordered a new rad anyway as I'm currently using the original rad which was refurbed a year or so ago. What the hell, money just seems to be slipping thru my fingers lately anyway

Ok so this is the tool I want: http://www.lislecorp.com/tool_...=1221, thanks I'll ask at the workshop where I take the car and see if they have one.