Twilight Zone Cooling

[Guest bigstuff]

Can anyone help on this one, I have 2 LTE efi with header tank and rad with manual fan. Out at the weekend amb temp about 20 Celsius, stuck in traffic engine temp rose to about 60 deg, switched fan on, engine cooled parked up , in less than 5 mins spurting non boiling coolant from pressure release cap

[philshelton]

Have you got a air lock? bleed the system and test would be my first port of call

[Guest Alan_builder]

Hi Bigstuff,

 

I think there is something wrong with the plumbing. It might be piped up wrong or blocked.

 

Lots of people have temperature issues, I never did, Ok the header tank blew up when I miss wired the electric fan.

So driving in France at 40 degrees C not a problem. The fan at tick over did flatten the battery while in a 3 mile queue.

Others on here may say plumb the system up in a particular way, not like that other guy says.

The confusion is around the center water water outlet on the inlet manifold. It is not there to stop hot spots!

This outlet has 3 common functions, the heater, the heating for carbs / choke and as a return for when the thermostat is closed.

So there is no need to drill the thermostat if the thermostat is bypassed correctly.

 

Have you checked your thermostat? Does it open if dropped in a can of boiling water?

 

Can you post some pictures of the plumbing, not so we can have a good laugh, but so we can see how it is plumbed in.

[Foz]

Had a similar problem with mine when something got stuck in the pressure cap & stopped it from holding any pressure at all - as soon as the engine warmed up it chucked about half a pint of coolant on the floor.

1 new cap & everything was back to normal.

Can you check if the system is getting pressurised or not ? Try squeezing the top hose as it warms up.

HTH Steve

[Snapperpaul]

Had a similar issue last week

Pressure cap was very weak causing coolant to leave at the earliest opportunity.

This caused an airlock which exacerbated the problem.

Airlock also made the water temp readings a lot lower than they realy were.

Also found an internally corroded thermostat housing with radwd muck all around the thermostat ( this was on my spare engine bought quickly to put in while I rebuild my super dooper one) replaced both now engine runs real cool

Edited August 2, 2012 by Snapperpaul

[Guest mower man]

Alan the hole inthe themostat is a recognised mod to help with curing air locks etc many stats used to have a 'giggling pin' in them for the same reason ,the connection under the carb needs to be there for circulation as you say ,if piped up correctly with an 82 stat a suck and blow system works very well ,mine stood in traffic in 90degs queueing to get into Lemans with no probs and is still doing it,s thing mower man

[Guest bigstuff]

Thanks for all the info guys, with your help I think we might have cracked it. This may or may not help some of you. The mistake I was making was assuming that the system I have is the same principle» as the sierra, not so. The Sierra system is pressurised with expansion accommodated by the header tank and does not have a pressure release cap on the radiator. I have just replaced the header tank cap, after loosing the old one on a 200 mile journey. The new cap was a sealed type. MY SYSTEM IS DESIGNED TO BE NON PRESSURIZED, hence any expansion was accommodated by the pressure release cap. Vent the header tank cap and hey presto !!2 Thanks guys