Neeek

OK, so I have an overheating problem. What are the things that cause overheating, then? I'm going by the process of elimination...

Radiator/engine water passage blockage
(flush will be prerformed to see if it helps)

Knackered (shutting) thermostat
(didn't have one, so can't be that!)

Timing too advanced
(maybe, but it's not pinging - I have a tick under load, but that's most probably lifters)

Carby running too lean
(would have to be REALLY leaned out to affect temp as it has done..?)

Dead bearing/broken impeller in water pump
(my current favourite!)

Cracked hoses
(all good)

What else?

northiam

I had overheating prob till I port matched the water pump volute thru the timing chain cover to the block and trim the gaskets to help flow. Also opened up the thermostat housing bend in the XC type housing. You need a die grinder or similar. What a difference!!

shaynet

Timing too retarded will cause overheating.

The main cause of overheating is loss of pressure in the cooling system. Water stays cooler under pressure. Find the leak! Pin hole in radiator? Loose hose clamps?

You mentioned in another thread that you had leaking welsh plug and fixed it by pouring chemweld or similiar in the system. Have you replaced the welsh plugs? What about the one at the back of the block behind the flywheel? If the others have started to go this one will be a likely contender also. Do it right 1st time and use brass plugs

__________________
The cop said "Do you know why I pulled you over". I said " Well, that all depends on how long you have been following me!"

Neeek

Haven't replaced the plugs yet, no. There doesn't seem to be a leak anywhere at the moment and the car behaved itself the other day. Previous to using the Chemiweld crap, there was a pool of water underneath the sump (from the leaking plug) but now there isn't, so I can only assume that the Chemiweld did it's job in that regard - I just reckon it buggered something else up.

Regardless, replacing the plugs is on my "to do" list, although I won't be using the car much between now and Christmas, so it gives me plenty of time to get it sorted. No doubt I'll say fuggit and just rebuild the 351 in my garage. Been meaning to do that for some time now...

Mr Jucy

I've had a gutless battery overheat my car because i've got thermo fans they wouldn't spin fast enough to keep it cool in stop start traffic until I got a new larger battery.
I also run stuff called Purple Ice in the coolant or water thats made by Royal Purple that keeps it running a bit cooler.

GammaBoy

I think We have a winner!
Put a decent thermostat in it (Repco, ask for thermmostat for Clevo with overheating issues) $20-$27 depending on how badly your local REPCO Rips Every Poor C*nt Off.....
See the thread that became a thermostat discussion...

Ben

streaksinthesk

i have been recomended the trident hi flow thermostats with every car i have had and they work like a treat.

TTNOS8

You seem to have skipped nearly the most important part in your cooling system. Your radiator cap.

What fan are you running?

Do you run an anti-boil/coolant?

Is it pinging? Lean?

What fan are you running?

Put a thermostat in.

Does the coolant level drop after getting hot?

If the car sits for a day or two, does the coolant level drop?

Can you borrow a pressure tester?

Belts slipping?

Buggered water pump?

Too many more questions. Help us out a little more :)

__________________
All Go, No Show
XE, 351C, Nitrous, 337rwkw
XW GS, Silver Fox, 302W
VS 215i Senator *For Sale*

Neeek

Fair point - but is was about 2 months old. It's now got a new one sitting on the bench - 13psi rated, I think and specific to the Clevo, say Repco. Not yet fitted because the car's not moving for a bit, but identical to the one I fitted a couple of months back.

Standard 7-blade. Thermos might help, but I'm not fitting them until the new engine goes in. Have to buy them first too!

Nope - just water. And I don't think water vs coolant is going to make my car overheat so dramatically, so I'm fairly sure it's not that.

Perhaps a little. We'd fiddled with it beforehand, but I refuse to believe that less than half a turn from rich to lean would have *that* much of an effect... and it does tick under load (and not under load for that matter) although I suspect that that's because the engine's a little tired more than anything else.

It always spits out the first litre once you've filled it up, and then it usually settles and doesn't lose any more. Water level was previously fine when fully warmed up. That is, until last weekend!

Nope. No leaks as far as I can tell.

Got one and fancy bringing it over? I'm going to have it pressure-tested before I do anything more, yes. Won't cost me much, and should help diagnose, so...

Nice and tight.

That's what I'm thinking, and it's next on the list to replace - I have a spare, so it's no biggie.

With regards to the thermostat, I'm not sure how NOT having one would make the car overheat. After all, it's getting greater water flow through the inlet without a thermostat in the way... sure, makes it's take about 4 hours to warm up from cold, but don't see how it can keep an engine running cooler out on the freeway once fully warmed up...

TTNOS8

OK.

A few more pointers to help out.

Please don't single out any of my queries as all together can make it a battle to keep a clevo cool.

And I notice your planing on putting a warm 351 in which will make it even more important to have it right.

The point about the radiator cap is to find out if its the right one or not. Is it recovery or non recovery?

Do you have a overflow bottle?

The fan should be ok. Thermos may possibly help, but yeah, the fixed 7-blader will suffice.

Coolant- I know this isn't the problem on its own, but any reasonable anti-boil will help the cause.

Mixtures- What do you mean 'half a turn'? Are you talking idle mixtures? I mean the actual tune of the engine as driving. I'm a little concerned regarding the 'ticking sometimes and not others'. This could be pinging. What is the inital timing at?

The water level will find its own happy spot.

OK, no leaks.

Thats good that you planning on getting it pressure tested. Let us know how that goes.

Belts are good.

Water pump sounds a bit suss at this stage.

Don't think a thermostat has one purpose only. Depending on the cooling system setup, taking the thermostat out WILL make the engine overheat. Plus it is not a good habit to remove the thermostat, it is there for a purpose. You may not care much for your present engine, but when you get your new one, engine wear at cold temps=yukky!

Lastly, and I really didn't want to scare you earlier, but head gasket is not ruled out yet either :(

See where I'm going?

__________________
All Go, No Show
XE, 351C, Nitrous, 337rwkw
XW GS, Silver Fox, 302W
VS 215i Senator *For Sale*