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MG MGB Technical - Running HOT under load

I have an '72 that is almost overheating under load, 70 mph up a grade in 80 degree weather. The car had been rallied by PO and has a Weber side draft carb. I have:
- drined and flushed radiator
- checked gauge (1/4 inch above N reads ~210 deg F on meat thermo.)
- added water wetter
- added radiator shroud
- Oil temp gauge reads ~190+ deg F

..and now if it is doing any real work ie. going up hills, it inches above N to almost 1/2 way to H. If I go at grade or down hill it will settle just above N and oil temp gauge will lag and drop from 190+ to a little less who knows 180-185.
I added a front valance this winter, there was nothing there before that. Is this part of the problem? Is 210+ too hot to run for several hours?
I have heard that mixture might be to lean or timing might be off.

Where do I go from here.

TIA
Jay Tracey

JT Tracey

Jay. Check the timing and mixture as you have suggested. My 68GT runs at the 3/4 point in summer and has done so for many years without problem. The LE type front spoiler seems to duct additional air into the engine compartment and my LE runs considerably cooler than either the GT or my daughter's 77 roadster. But, I cannot say whether this is a difference in gauge reading or an actually more efficient engine compartment cooling due to the spoiler. One of the many things I need to experiment with as time becomes available. Les
Les Bengtson

Sounds fairly normal to me, and is a long way from true overheating, just slightly warmer than normal which given a hill and 80 degrees is not surprising. 1/2 way between N and H is only a few degrees, and is the normal switch-on point for electric fans (90C 194F). It just means the stat is fully open and the ambient air flow and temp is not quite enough to take away all the heat the engine is generating. I think you would have to push it a lot harder in significantly higher temps to get it anywhere near H and true overheating. Having said that if you are running with slightly retarded timing to cope with lower grade fuel that will increase running temps.
Paul Hunt

Can anyone tell me what is the normal coolant temperature and what is considered hot. I just rebuilt my engine and as I run it now,, when I am making power or going up long inclines the temp guage reads 212 or a little over. I whould like to know if there is a danger. I put an adjustable timimg gear on and have it retarded about 4 degrees but I have my distributer advanced a little ( head work and needed this set up to get some low end torque ). Any help would bve greatly appreciated. Thanks
Ed Kulick
E kulick

Thanks for your help guys, I guess I will continue to run as is and see if a problem develops. It was 95 deg F here the other day and ran it at 70-75 for 15 minutes up hill and it stayed at 1/2 way between N and H (210-215 Deg F so hot but not too hot.

Thanks again! Jay
JT Tracey

This thread was discussed between 26/06/2003 and 27/06/2003

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