Pinto cooling conundrum

[Mike Bell]

OK, I've just got my Gp1 Pinto back from rebuild after it (according to the builder) overheated. Surprising considering that the cooling system was all new, including a large core radiator.

One suggestion from said builder is that, as no thermostat was fitted, the coolant was possibly circulating too quickly. The remedy could be to fit a flow restrictor plate in the thermostat housing.

Sound feasible?

[Moosehead]

Had the same issue with mine (SBF) but it wasn't that it was circulating too quickly as such it was the fact that with no restriction the pump was aerating the coolant. With a restrictor plate in place of the thermostat and with no other changes the problem went away.

[Good Times]

BMC engine;s have a blanking sleeve with part number, this would replace the thermostat.

[GORDON STREETER]

Just take the centre out of an old thermostat and use the outside, on the Kent engine always blank the bypass hole off in the water pump otherwise the water doesn't flow round the back of the block.

[IAN #51]

I picked this up a few years ago when i raced my Triumph Spitfire.We used to just remove the mechanical workings and leave the thermostat plate in place. If we took the whole thing out they overheated, not sure why someone told me it was to do with flow vs pressure but i cant explain why.

I currently run a Cosworth YB with the mechanics of the thermostat removed and the thermostat plate in place and it works well.

Ian

[Mike Bell]

Sounds like a done deal then. Lucky still have the thermostat that came out originally. Thanks all for passing on your knowledge and experience!

[zefarelly]

I do the same as Gordon suggests. If the water circulates too fast you can get cavitation. also check there are no odd hose routes ( unlikely I know) causing an air lock

remote things are great for that, but in an old Ford you shouldn't have more than 2 hoses and a rad.

With the best will in the world theres usually something dislodged from a block once its been run a few times, so a backward flush wouldn't hurt either.

[midgetman]

You could also try a bigger water pump pulley. There used to be a steady demand for (IIRC) Marina pulleys amongst MG Midget racers when I was selling spare parts.

We always ran with a thermostat plate too.

[Cliff Ryan]

Thermostat restrictir plate & larger water pump pulley cured overheating in my V12 as it stopped the coolant cavitating, so should help the cooling system work as it was originally designed to.

[zefarelly]

Or take the P*** out and put a crossflow in

[Tel 911S]

As said by the others , you need a restrictor in if you have no stat as the circulation will bypass the back cylinders . And if revving at over 7000 then slow the pump with a larger pulley .

Another problem which we have had come up in the last few years might be worth looking at . Oil filter canisters seem to be thinner materials than they used to be , [ far East made ? ] , & expand under pressure . They can then work loose on the thread , & it is possible to come undone by itself .
We now have a little bracket on the Pinto block by the filter , & a Jubilee clip on the filter body stops it coming undone .

[Moosehead]

I always either lockwire or cable tie my oil filters. Never had one come loose but for such a little effort don't need the worry.

[delta]

Interesting thread this one . On the Ff2000 engines I now always pin the water pump pulley to the water pump shaft as we have had the aluminium pulley expand then start to slip on the pump and hey ho over heating . Yes to oil filter housing coming loose and again the jubilee clip idea does the job . Happy engine building everyone

[midgetman]

Interesting re oil filter, a car in front of me one day had that happen at Zandvoort. Result - one trashed Midget plus quite a bit of damage to mine. All quite exciting.

[356mal]

gordon
where is the bypass hole to blank off in the water pump ?

[zefarelly]

its goes from the front of the block above the impeller and up to the head face, either block the hole in the pump or the block.

Another thing to consider is head gaskets . . . a lot of aftermarket ones don't have all the right water way holes in them . . . for example a precrossflow AH760 Payen has different sized holes front to back . . . a crossflow one doesn't. some have none, so it affects the water flow/route

I've also suffered overheating from a very thin bore wall in the past . . .