Car seems to rev high + get HOT VERY quick (My hot Car)

[dannyboy2005]

When i drive on the motorway, 9/10 the gauge is in the top quatre.

I noticed today (When giving 4 adults a lift) that the needle was almost in the red.

Dad said its because you only have a little engine and can't carry all this weight, so was understandable.

Just picked sister up from prom, 30 seconds walk away and turned the ignition on and the needle was in the bold white bit on the gauge. Got to the school (No further then 1/2 mile @ 20MPh max?) the needle was almost in the red again.

Waitied 20 mins and let the car cool down then she got in, started engine instantly the gauge slowly climbed just below the red.

Any ideas? Coolent seems fine and recently had it changed 8 months ago. And yes, i did bleed the system afterwards.

And as for reving high. Even at 60MPH in 5th gear the revs are at about 3,250RPM which seems pritty high.

I know its only a little engined car but its not seemed to rev that high before.

Can someone help.

[BobC]

Hi,

Try changing the thermostat.

[dannyboy2005]

I herd that putting it in boilging water will clean it up and if the valve opens the thermostat is fine?

[scot-ish]

yup, you can test it like that, its a wax controlled valve(well is on the ones i work on at sea) so you can put it in hot water, and see if it opens, if it does, and is working good, whats your oil/coolant like?? they in good nick, no signs of head gasket failure??

[Darlo-paul]

Maybe headgasket related?
Noticed any excessive white smoke coming out of the exhaust? Mayo on the cap etc

[dannyboy2005]

Well checked the caps on the engine and coolent cap and both were clean.

I'll have to do a longish journey (20 miles or so).No white smoke and not yet checked the coolent as said, only did it 8 months back so wouldn't had thought id would had dropped but will check tomoz.

Putting it in boiling water is good, but how do you know it wont open at 95*C? instead of say 60*C ? A thermometor i guesS? (I don't have one)

[BobC]

Hi. Only need to test it if you want piece of mind. They are around £10 just replace it and play around with the old one or just chuck it. No point in buying a thermometer as you'd be better off with the thermostat.

They are wax based and eventually they stop working and do not seem to be part of any routine servicing. If they fail them they are probably the most common cause of head gasket failure.

[redsaxo22]

Well checked the caps on the engine and coolent cap and both were clean.

I'll have to do a longish journey (20 miles or so).No white smoke and not yet checked the coolent as said, only did it 8 months back so wouldn't had thought id would had dropped but will check tomoz.

Putting it in boiling water is good, but how do you know it wont open at 95*C? instead of say 60*C ? A thermometor i guesS? (I don't have one)

you should check all fluid levels every week. i'd say your thermostat is not opening and allowing the water to circulate the engine. does your engine fan come on when it gets to just over half-way? :P

[Stevo123]

+1 to replacing thermostat, don't bugger about testing it because it may open but not fully etc.
Check radiator condition, if it's all corroded then it needs replacement because it can't do it's job unless it's in good condition. If not corroded make sure it's clean and not obstructed with anything (stray tesco's bag etc etc).

Flush sytem with hosepipe while thermostat is out, USE ANTIFREEZE when filling it up, something around 50% mix with normal water is okay. make sure you bleed sytem correctly enusring to use the coke bottle upside down in top of radiator trick - bleeding without a header of water above the engine is wasting your time.

[dannyboy2005]

you should check all fluid levels every week. i'd say your thermostat is not opening and allowing the water to circulate the engine. does your engine fan come on when it gets to just over half-way? :P

No, fan dosn't come on untill in the middle top quatre. Then it only comes on for a 2 minutes or so to bring it back down to 3/4. Its always been like this since i fitted my dials.

+1 to replacing thermostat, don't bugger about testing it because it may open but not fully etc.
Check radiator condition, if it's all corroded then it needs replacement because it can't do it's job unless it's in good condition. If not corroded make sure it's clean and not obstructed with anything (stray tesco's bag etc etc).

Flush sytem with hosepipe while thermostat is out, USE ANTIFREEZE when filling it up, something around 50% mix with normal water is okay. make sure you bleed sytem correctly enusring to use the coke bottle upside down in top of radiator trick - bleeding without a header of water above the engine is wasting your time.

My Rad has a few of the bits of metal bent, where stones have hit it and a few fryed flies, other then that its Silver and not 'Limescaleed'.I'll be better topping up fluid (Which i checked and is quite low) then trying it. If its still hot change the thermostat

When taking the thermostat out, do i have to drain the coolent system or can i just unbolt it and it will come out?

Would i be better using distiled water or water fom the tap?

Thanks.

[Phsyco_Paff]

No, fan dosn't come on untill in the middle top quatre. Then it only comes on for a 2 minutes or so to bring it back down to 3/4. Its always been like this since i fitted my dials.



My Rad has a few of the bits of metal bent, where stones have hit it and a few fryed flies, other then that its Silver and not 'Limescaleed'.I'll be better topping up fluid (Which i checked and is quite low) then trying it. If its still hot change the thermostat

When taking the thermostat out, do i have to drain the coolent system or can i just unbolt it and it will come out?

Would i be better using distiled water or water fom the tap?

Thanks.
did you take note of where the needles sat befour takeing them off to fit your dials because if you didnt that explains y its going up to 3/4.

it dont overheat so its not the thermostat but change it anyways as i think it should be included in a service

[woody813]

I got same problem pal, im going to check thermostat. . .

It never gos into red but sits at just above 3/4's with the fan on...

Another thing to look oout for is slight wear to headgasket, which may be it.. apparantly look around for oil near the alternator... which mine has! :( yay... not!

But i rekon mine is probly just thermostat, not letting enough water round engine to cool it, cos it should go colder as cold air hits the rad, especially if your going quicker- unless your head gasket is going... lol

[dannyboy2005]

did you take note of where the needles sat befour takeing them off to fit your dials because if you didnt that explains y its going up to 3/4.

it dont overheat so its not the thermostat but change it anyways as i think it should be included in a service

Hi

I didn't need to change the temp gauge dial or even touch the needle. I drained system and fitted a new stat. Temperature has dropped a bit and i did flush the system correctly but now it drops to 3/4 (if i'm lucky) but mainly sits a needles width BELOW the bold HOT mark at the top of the gauge. Luckly its not in the red but far to hot and the fan is kicking in every few minutes.

What else can it be?

[dannyboy2005]

http://www.saxperience.com/forum/showthread.php?t=243602

[Mark1]

Yes something doesnt seem quite right there....

[lurchsaxo]

its ur water pump mine was doing the same this water for the over heating
but the over reving is eles

[johnlambert]

same problem too!!!
just got the headgasket done on my sax;ill have it back tomo so ill know then.
new water pump too!!

are there any records of someone getting a new head and water pump and its still over heated??

obviously related to sensors,thermostat ect