Overheating of car and driver

The previously reported overheating in my '64 was reduced quite a bit by squirting some oil on the water pump shaft, tightening the belt, and changing from a 190 to a 180 degree thermostat. At 65 mph the temp stays between 195 and 200, but in traffic it is 210 - 215, sometimes worse. Obviously the fan isn't doing its job. I saw an electric fan conversion covered in a repair book, which makes me think that the mechanical fan may be a common problem with MGB's. Is it? Also, there's no fan shroud. Would that make a difference?

If you look in Moss at the fans, you will notice an increase in the number of blades over the years. That would indicate a heating problem.
What are you using to find the temp? Are you boiling over?
It might be your water pump, not the fan. Have you flushed out the block and radiator?
Bs never had a shroud; the seal to the hood and the foam between the radiator and support forced all air through the radiator.
You might try a 165 thermostat.

You probably need to have your radiator rodded out by a radiator shop.It may be that the flow is restricted by build up over the years. No amount of flushing will correct that problem. It could be that it even needs to be recored. If it does, I would recomend that you have them put a heavy duty core in it. I don't recomend buying these radiators sold by the parts suppliers. I have had a lot of trouble with them,over and over. Chris, made a good suggestion about puttin a later model fan on it.,but I don't think that's your pronlem. I have worked on too many early B's and MGA's with the early fan and not had an overheating problem. The deal about putting oil on the shaft to help is out there in left field some where.

As an auto parts salesman I have to go along with Tom on aftermarket radiators. Many of them are made super cheap because the parts business is so competitive. A good radiator shop should fix you right up. When I rebuilt my B 5 years ago I had the radiator gutted and gone through and I've never had an overheat under any conditions. It gets into the upper 90s a lot around here and 100s are not uncommon. As an aside. When you paint a radiator go very light in the fin area, just enough paint to color, not coat it.

Chris, for temp readings I'm relying on the dashboard gauge, which looks like it's stock. My car doesn't have any hood seal or radiator mount foam. I flushed the block and radiator, took the radiator out and back flushed it. No obvious problems.

Tom, while the radiator was out I turned the water pump and it seemed tight. A spare pump that came with the car when I bought it was also smooth but tight. I was going to mail order a new pump, but saw in Haynes that early model water pumps should be lubed every 3,000 miles. I doubt that many owners do this. There was no obvious lube hole in the casing so I squirted oil on the shaft, and it worked! Thinking on it some more, a new pump might still be a very good idea.

I don't think the hood seal (on the core support) and foam would make that much difference, but they do direct air through the radiator.
The reason I asked about how you got the temp was, could your guage be off? If you're not losing coolant, you're not overheating.

I did have my radiator recored and I installed a 190 deg thermostat. I have a new seal between the radiator and hood but none along the sides of the radiator(yet). It gets between 90 and 100 often enough around here to put it to the test. I used to drive it everyday, year round. The radiator cap is something to think about. I am not sure but I think mine is either 7 or 10 lbs. I'd have to check it. It rarely runs over. I do not have a recovery system installed either. That reminds me, its probably time to flush and redo the water/coolant. The gauge (original dash gauge) almost never goes up to half way.

I think the British car manufactures were in denial that they're cars were being driven in temperatures exceeding 50°F. "add another blade to the fan until the problem goes away" a good example of this is later model Triumph Spitfires, they ended up with a engine driven fan that looked like an phenastrom tailrotor on a helicopter. But some food for thought, now being the winter, with temperatures hitting the high 40°f range in my area, I have yet to turn on the electric cooling fan (with no engine fan)on my 71 GT under around town driving conditions. I am working on getting rid of the manual fan control, no bank available for a rheostat yet. So if you find the engine running hot and the outside temps are low(less then 60°f), you may look elsewhere for your overheating problem other then the fan.

I agree with Tom. Clogged rad.

Just because water seems to flow thru the rad OK doesn't mean it is an efficient radiator. Scale build up on the iside of the tubes will not conduct heat therefore causing an overhearting problem very much like you describe.

IMHO, I'd convert to an electric fan while the rad is out. Makes the car quieter and seemingly faster, easier to warm up (VERY important) and more efficient on the cooling side..

How does an electric fan make the car quieter?

If you get a big enough fan it will propel the car and you don't have all those engine noises and nasty old polution.

I dropped about 400dba getting rid of my engine driven radiator fan, that thing whirles like my house A/C fan. You do pick up a noticable amount of HP, I suspect five HP. . I was watching shade tree mechanic, and they stuck a electromechanical fan on there monster Dodge P/U, it was an engine driven fan, with an electric clutch to engage it when needed, they picked up something like 20 HP when it wasn't engaged, pretty sweet.