engine temps...

[peteA]

my cerb seems to be running 'hot', its a 98 4.2.

Its fine when starting from cold...on the move it sits at 80ish on the gauge (and about 55/60 oil pressure) but if I have to stop/start in traffic it quite quickly rises to over 100 and I have seen it at 110 today on the gauge (with the oil pressure @ 30ish at idle and 55 on the run).

If I get on the move again it starts to drop but quickly rises again if I stop or slow down or even get stuck following something like a truck or van.

I know the temp is high at 110 and it could be due to the gauge reading high?

Was wondering what sort of figures are typcial...especially on hot/warm days?

Obvious thoughts are faulty/inaccurate gauge and will check the fans are coming on but worst thoughts are water pump..? Will do a quick check tonight for trapped air by bleeding the headers and the rad.

Thanks in advance.

[2mad]

hi could be leaking radiator check down the sides of the rad for green colour
liquid and bottom of rad also the water manifolds are prone to corrosion best to change them for stainless steel or the seal on the water pump has gone.
check the water level and look for any leaks under the car.

[optimax sniffer]

Probably the guage over reading. IIRC the sense line runs past the exhaust manifold and heats it on the way to the guage. I think anything up to 10 degree overead.

The only way to check is to connect a 'puter and use the diagnostic program.

[DonnyMac]

optimax sniffer said:

The only way to check is to connect a 'puter and use the diagnostic program.

What he said^^^ I think that if the system needs to be bled that the gauge will jump wildly around now and again (air in the system).

At what temps are your fans kicking in? If they're late (on the gauge) then it may well be that the gauge is out by a fair margin.

If you're having overheating (or reading) issues I guess the car has yet to be sent off to Joo? Whirlwind + re-map is the best money you'll spend and guess what... you get cooling magic built in - rarely see mine break 90c since it was done, which removes the temp anxiety.

[sk7ine man]

DonnyMac said:

optimax sniffer said:

I guess the car has yet to be sent off to Joo? Whirlwind + re-map is the best money you'll spend and guess what... you get cooling magic built in - rarely see mine break 90c since it was done, which removes the temp anxiety.

What is the whirlwind?

[peteA]

DonnyMac said:

optimax sniffer said:

The only way to check is to connect a 'puter and use the diagnostic program.

What he said^^^ I think that if the system needs to be bled that the gauge will jump wildly around now and again (air in the system).

At what temps are your fans kicking in? If they're late (on the gauge) then it may well be that the gauge is out by a fair margin.

If you're having overheating (or reading) issues I guess the car has yet to be sent off to Joo? Whirlwind + re-map is the best money you'll spend and guess what... you get cooling magic built in - rarely see mine break 90c since it was done, which removes the temp anxiety.

I wasnt too concerned about the 'high' temp as I know the gauges are prone to over reading and knew I wouldn't be in much stationary traffic but just want to be sure.

when I got home last night I let the car sit idling and sure enough the gauge crept round to 110 Deg C when the first fan cut in...that brings me to my next question: the fans do kick in stages don't they and dont both come on toghether?...at what temps (standard - I know Joo does a chip lowering the temps)? When the fan cut in the temp started to drop so I switched the engine off rather than wait to see if the second fan worked...

There are no obvious leaks and I also checked the coolant level when it had cooled down later on and it was spot on.

Doesnt the blue cap on the coolant system 'blow off' at a certain temperature...from memory 105 Deg C or something? So if my engine temperature was actually 110 would it have let go..?

Thinking of buying/borrowing one of those laser temp reading thingys and spot checking the engine/coolant temp.s around the engine..?

If the gauge is over reading whats the options...can it be reset or calibrated? Does anyone sheild or insulate the 'feed line' as it passes near the exhaust...?

Cheers

[Storer]

Joo's cooling chip works wonders as does some water wetter added to the coolant.

Another improvement would be to change your oil pressure relief valve spring. They get weak after a while. My oil pressure went up by 15psi when I had mine changed.

[optimax sniffer]

sk7ine man said:

What is the whirlwind?

Joo ( spitfire4v8) developed a short induction kit and chip package that is know as the 'whirlwind'

[2mad]

the cooling fans are operated by the ecu your car properly has air con so the first fan cuts in and the second fan cuts in with the a/c on depending on
the temp the blue cap wont blow off but dont open it under pressure .it might be worth checking under the front panel undo 8 or 10 allen key screws under neath are the water manifolds and loads of hoses.if your happy theres no leaks then water wetter which is a chemical to reduce the water temp down
around 10% could be used and also the cooling chip aready mentioned which you
can change youself in the ecu

[VPower]

Pete

I suggest you change the thermostat, flush the system and refill with fresh red stuff.

You symptoms of running at 80 seems to me to indicate that your thermostat could be the fault.
When they fail they tend to fail open a bit, which means they run lower than the set temperature.
But this failure mode also means they can't fully open and your flow through the rad gets restricted and you get over heating in slow traffic.

A good flush and chage of antifreeze is worth doing as you'll have to drain it anyway and RED antifreeze is much better for the engine than the old blue stuff!(apparently)


Steve

[peteA]

VPower said:

Pete

I suggest you change the thermostat, flush the system and refill with fresh red stuff.

You symptoms of running at 80 seems to me to indicate that your thermostat could be the fault.
When they fail they tend to fail open a bit, which means they run lower than the set temperature.
But this failure mode also means they can't fully open and your flow through the rad gets restricted and you get over heating in slow traffic.

A good flush and chage of antifreeze is worth doing as you'll have to drain it anyway and RED antifreeze is much better for the engine than the old blue stuff!(apparently)


Steve

Thanks for the advice Vpower

I carried out alot of refurb work over the winter including changing the hoses to the poly type, stainless pipes from ACT and new coolant (orangey stuff recommended by opie)....wish I had checked/changed the stat for the sake of it...?

The engine heats up relatively quickly/consistantly and, so long as I keep moving its fine....its only when I slow down or stop...but thats when any restriction due to the stat would be apparent...good point...

Come to think of it...where is the stat...is it easy to get to?

Thanks again

[amazon]

With mine, sometimes the needle goes into the oil

But the temperature is actually fine when checked.