Rising Water Temperature

[Rich Cheung]

Hi Guys,

Hope you can offer some pointers on this.

Off boost my water temp sits around 90 deg. Soon as I go into positive boost or drive at high speeds I am seeing my water temps steadily rise. I have seen temps upto 105 deg on the motorway. If I free wheel the temps will drop back down again to low 90\'s. I am not loosing coolant though.

Any ideas ?

Rich

[probedb]

Hmm, 90s is high? I get into the 90s if I floor it. Usual cruising at motorway speeds is just over 80 for me. Not as modified as you but still? Is your coolant definitely topped up and everything? I only get to 100+ if I\'m in standing traffic.

[andysmee]

mine runs in the 90\'s when cruising (social domestic and pleasure) and goes over 100 when cooling down. this morning it managed to stay under 90 whilst commuting.

[Rich Cheung]

Hi Paul,

If I stand in traffic all is fine goes to about 94 deg tops.
Its + boost and higher road speeds that cause it to rise.

Oh btw are you out this weekend around town ? Its my B day so hoping to get over there Sat night. Let me know if you fancy meeting up for a few :guinness

Rich

[antnicuk]

if your temps go up when you are moving at speed it generally means its the rad or not enough air getting to the rad, if it stays cool in traffic it must mean your fans work ok, not that you should need these at high speed.  Have you changed anything recently at the front of the car?  
The other thing could be water seals,  how long since your rebuild?  But you would normally see pressurised water system and loss of coolant.

[ro284]

Plastic bag stuck in rad? dead badger, seagull or something, my temps are steady at 85 when cruising along and only rise in traffic at a standstill to  90-95, when the fans come on (standard motor no mods ) but thermoswitch mod, i thought going fast would bring temps down with the extra volume of air going through the rad.
Bob

[Mr J.T]

agree with antnicuk about the air path,

i see 80-84 slow drivin up to 90 hard hard boot. never anythin above

[gsb876]

I think the front of your car doesn\'t help Rich,

Need to make a vent for more air to get to the rad somehow mate, it sounds that at high speed the air is being restricted from getting to the rad hence the higher figures on the m-way, if you have thick mesh that too will not allow enough cold air to feed through.

Although at track driving 105oC is not uncommon from what i hear ?

Gurj :Thumbs-up

[Rich Cheung]

Thanks for all the info guys.  
Gurj - Yes I know what you mean about the front of my car.

I\'m hoping its not water seals. Checked coolant this morning and had lost some but not much. If I undo the filler cap when the water has cooled slightly and I see champagne bubbles is this what you mean about the system being pressurised (bubbles being the release of pressure) ?

If this is the case is there a short term fix to prong life of seals ?

Rich

[antnicuk]

If your engine is pressurising the water system it will be pushing the water into the overflow tank.

An indication is to start it up from cold with the water cap off (not the ast) and then look for little bubbles rising up in the water.

Taking a cap off while its warm wont really tell you much cos the system should be under pressure by the time its warm.  

I would just see what happens to the water over the next few weeks,  look for things like steam from the exhaust and difficulty in starting when warm and loss of coolant.  Keep an eye on your waer level and temp.

Then try and sort out the air flow to the rad.  Have you got piccys of the front?