31 replies to this topic

[SA-GTS]

I have a South African 1275 GTS with a 1380 motor, after machining and getting it on the road it is running hot, just to the shops it sits between 100-110 degrees C. We have flushed both the engine and radiator with radiator flush, the water before and after was light brown/rusty, we refilled it up with antifreeze/coolant. Even after this it is still running hot! What would be the best solution to this? The car hasn’t been set up on a rolling road yet and the carbs are running a bit rich (assest do to spot on the tail pipe)
Thanks in advance!

[Spider]

Welcome to the forum

[Bat]

Hi,

Welcome aboard.

Is everything new, radiator, pump, stat?

Is the timing set correctly?

Have you put the fan on the right way round?

Cheers 

[nicklouse]

and id the gauge wired correctly and the sensor correct for said gauge.

 

is it actually getting hot?

[SA-GTS]

Thanks for the reply’s, the car was taken to a mini expert who got the timing correct and the twin carbs balanced and running properly, there no flat spots or lumpiness when driving. As for the gauge it’s a new gauge with its probe machined into the head, fan is the correct way around (first thing I checked) and all flushed with radiator flush according to its recommendations. Pump was checked prior to going back in and the thermostat has been checked. We also used a highly accurate digital external gauge and it is spot on the same Guage... so not sure where to go really...

On a side note now living in the uk and planning on bringing my mini over next year.. should be one of two GTS in the uk!

[carbon]

A freshly rebored engine will tend to run a bit hotter until the rings bed in.

 

Also worth checking that there is not excessive friction. For example if ring grooves in the pistons are not deep enough it can be assembled and have correct ring gap, but when it warms up the rings get tight. Shouldn't happen if pistons and rings are correct, but not unknown.

[Retroman]

I am guessing its pretty hot in SA do you know what rad it is, and are the gills clean?

 

Are you running a thermostat ?

[SA-GTS]

So the engine has only done about 500km since a full rebuild, the pistons I’m using are Nissan Sentra 1400 (rings came with the pistons) bored out to a 1380 with a 10.5:1 CR with a metro head. The radiator is the original 2core with no bent fins, it’s running a thermostat that was new when rebuilt, it isn’t much hotter in Sa than summer in the uk..

[SA-GTS]

I assume to check for play/movement on the rings I’d need to strip the engine completely again??

[Spider]

Other than being bored out a long way, are there any other mods to the engine, intake or exhaust system?

[SA-GTS]

No, the intake is still the original twin su manifold, head has NOT been polished at all and the exhaust is still branches leading to a 40mm straight free flow

[Retroman]

To my way of thinking you need better rad and a 74dgree stat or a blanking sleeve

 

When I do any big cc engines i cut the water jacket at the back side of the water pump

 

and various oil gallery pump work which helps keep the temps down

 

http://www.minispare...|Back to search

[carbon]

I assume to check for play/movement on the rings I’d need to strip the engine completely again??

Does the engine seem at all stiff? You could do a basic check by taking the cylinder head off and then put the piston to top dead centre. There should be about 15-20 thou gap between piston and bore, and you should be able to move top of piston fore/aft until the top land of the piston almost touches the bore. Also if head is off check bores for any signs of unexpected polishing which could indicate the pistons/rings are nipping up.

[SA-GTS]

Nope doesn’t seem stiff at all, it does battle to crank thou if you press the clutch in for some reason, however I think that is a separate issue.. I have a bore scope somewhere that I can put in to check for polishing ect.

[SA-GTS]

@carbon surely changing the radiator isn’t really solving the issue? Isnt it a case of working out if the cooling system is to small for the setup or if there is something creating to much heat?