Outer Limits 4x4 Board

I've pretty much finished the EFI conversion now, and all seems to be running fine.

My coolant temp guage is reading fine, but I have a slight feeling the engine is running too hot. The exhaust gas and the engine bay, seem to feel really bloody hot to me.

There were some modifacations to the magna water jacket in the inlet manifold, and the thermostat housing has been reloacted to accomodate, but it's still hooked up to the front port on the manifold. This was done by someone who's done these before and never had a problem.

What do you think? Any ideas anyone?

Exhaust gas IS hot - it's a byproduct of stuff burning. When you first start your engine what's coming out the pipe may not be too hot, because the gas gives up heat to the exhaust system - steam in the exhaust will condense, and water drips out the tailpipe. Once everything's heated up, less heat is lost to the exhaust pipe/muffler, so the gas coming out the tailpipe will be MUCH hotter. Tailpipe temp will also be dependent on flow - lower at idle, higher at high rpm/load.

Under bonnet may be a different issue. If coolant temperature is OK (and your sender/gauge are working properly) then it may be an efficient cooling system is masking a problem - extra heat from somewhere is being dissipated through the radiator, but where does all the hot air go?

Take it wheeling on a hot day, and see what your temperature gauge does. If your temperature climbs, that's probably a bad sign that the cooling system isn't coping with the heat your engine is producing. If that's the case, you need to establish if the problem is a result of the modifications, or a fault.

All in all, I guess I haven't helped.

Exaust gas bloody hot? I'm not an expert but after a mod like yours first thing you must check anyway is air/fuel ratio.

Thanks for your suggestions guys,

A/F ratio is managed my the ECU (It's a stock magna ECU), that being said, there's not EGO sensor, only AFM at the moment. The AF ratio was very rich witout the AFM attached (limp mode), seems to have leaned out since that's been installed.

I'll check the readings off the sender on a multimeter and see what the sender is doing. Might try to pick up a temp guage from somewhere, it would still be using the same sender though. I'd better check that too!

The extra head i've noticed, is while the vehicle is stationary! Not head build up due to driving. Oh and the bonnet is up, so heat build up shouldn't be an issue.

Doesn't seem to be boiling coolant though, and the overflow is staying pretty constant. System is pressurised except for the tiny leak from a welch plug on the exhaust side. Not too bad though.

extra heat from somewhere is being dissipated through the radiator, but where does all the hot air go?

Ah I get it... What might me making excess heat though? Uh... poor timing, bad AF ratio??