I know the purists will be aghast but I machined a housing to clamp to the dynamo and mounted a small marine pump driven from the same belt( I had to use a timing belt due to limited wrap) that drives the fan. I also incorporated a thermostat in the top hose to the radiator--all seems to work well.The engine is a coil unit and yes I used a 4 bladed fan.

Hi Ken,

Nothing wrong with the odd mod or two! Thinking about what you have done:-

The thermostat should make sure the engine comes up to temperature quickly, there were several 'after market' products available in the 50's and 60's I belive that fitted into the top hose incorporating a thremostat.

The pump is obviously circulating the water and therefore improving the flow. If this has resolved your overheating then it points to the fact that you have a blockage or restriction which is impeeding the un-pumped flow previously. My advice would be to find the cause of this problem because if it gets any worse then the pump may eventually fail to cure it.

An Austin Seven engine with clear water ways works extremely well, having travelled many miles, sometimes in hot conditions, I have never had overheating. I have had vapourisation of the fuel but that is another story!

Hi Ken

I agree with Malcolm on this one. The original cooling system, providing all is in good order, will do that is necessary in cooling an unmodified A7 engine. If you've modded the engine to get more power of course then that's a different situation.

Question. Did you provide a bipass to ensure a pumped circulation round the block before the thermostat opens?

Martin

Oops, sorry. That should have been 'will do ALL that is necessary'
Martin

Yes Martin Guilty as charged--The engine has an Ulster head, Jack French cam &, followers, 1-1/8 inlet valves, Phoenix crank & rods, Honda pistons Hilman hunter oilpump, filter & adjustable relief valve.all coupled to a brand new ( yes realy never used-- been in storage since 1930 ) CR gear box.

Martin, I forgot to tell you I drilled a series of holes in the themostat to get some flow to actuate the the thermostat.

Hi Ken,

My RK saloon has a Supaloy head, Phoenix crank, 1 1/8" inlets, modified ports and uprated oil pump but I am not having cooling problems and the RK has a smaller radiator than the later models and no bonnet vents. It is an everyday car that has travelled well over 4000 miles since May this year.

Why yours is overheating is still the question.

Malcolm,
Fact is my engine is not overheating and I did not install a water pump after having problems--That is the way I built the engine. I agree with one of the correspondents that a standard engine and radiator is able to run trouble free as long as the block and head is clean and you do not have a kink in the bottom hose. After 52 years of owning various sevens I wanted a reliable engine that could run at freeway speed for hours in our North American Summers.

Sorry Ken,

I realised after I sent the reply that I had got my wires crossed. It just goes to show that if you and I both run an uprated engine without cooling problems ( albeit yours is assisted ) then there must be a problem with other cars which are overheating in our temperate climate.

My apologies.

The thermostat you have included in your system, was that ( dare I say it ) home made or was it one of the old ones designed for the A7?

regards

Malcolm

I turned up a housing from aluminium (two piece screwed together) and used a~ 1980 Dodge Colt thermostat. I modified the thermostat by drilling3----5/64 holes in the valve plate (for water flow to actuate thermostat)The whole unit fits between the cyl head and the rad.I am at present using a 180 degree setting but 185 & 190 are available.If you want details give me your "snail Mail Address"and I will send.