Morris Minor Owners Club

Hi,

does anyone know if there is a stronger water pump for a 1275 engine that delivers more flow than the original one?

Backgrounds:

The company doing the dyno tests on my car has managed to overheat the engine killing the head gasket the second time. (
They are now asking that question because they argue the water flow of the original pump may be too low to cope with the heat produced by the seriously tuned head a.s.o.
To answer queries in advance:
Timing is 12°advanced and cooling system is clean.

I have a distributor containing an electronic ignition installed. But that one seems to regulate all the time. I have now changed that to a standard distributor without electronic ignition an wait for results.

Thanks for your input

Chris

I fitted one of these to my 1275 Mini and there was a noticeable reduction in temperature. They also do one without the bypass

https://www.minispares.com/gwp134evo-su ... ith-bypass

Of course there could be another fault with the cooling system causing your issues.
An alternative is a Davies Craig electric pump, I fitted one to my mildly tuned Sunbeam Rapier engined Commer Camper and it works well.

I would suggest that there is something basically wrong with your seriously tuned engine to cause the head gasket to fail twice.
My own seriously, seriously tuned 1380cc 'A' Series engine has never had a overheating problem.
The 1380cc engine was originally fitted with a Davis Craig electric water pump with electronic thermostatic control which never gave any problems. The Davis Craig water pump is fitted next to the rear mounted radiator.
I have now reverted to a standard type water pump as per panky's link as I want good circulation out through the back of the head to the intercooler and back to the bottom hose. I will most likely retain the Davis Craig water pump to service the rear mounted radiator.

@Panky

Thanks for that link.

@ Phil,

before I drove the car to the workshop to do the dyno tests I had about 1500miles without any thermal problems. I have driven it at different speeds and with revs up to 5000 at the end. Not a single minute with exeeding temperatures. So I don’t think it’s a general problem of the engine but one of the dyno testing.
These test are done just to find the correct needles for the HS4-carbs and a good adjustment.
Maybe I do better not looking for perfection and stay with a standard solution.


Chris

Seems to me the problem might lie with the testing rather than the car.
Perhaps they just aren't testing it in a manner suitable for the technology of the car, i.e. from the 1960s/70s....

My Minor has been on a rolling road and it never produced any problems.
Most if not all rolling roads have a high power fan blowing cold air through the radiator when the engine/car is on the rolling road..
Did they have a external cooling fan?
Do you have a cooling fan fitted to the water pump?

Hi Phil,

Yes, they have an external fan with the rolling road. When the head gasket blew up the first time they forgot to switch on that fan. The result was a serious damage to the engine with damaged pistons and main and big end bearings. Flollowing that the engine was rebuilt completely including new and lighter conrods an forged pistons a.s.o. After that rebuild the engine ran perfectly on a stand for at least 6 hours in the workshop. Back in the car the engine overheated again when testing but I don’t know how long it has been running then.
I got the idea that the mechanic possibly has misconnected the electric fans in the car. If the polarity is wrong connected the fans do not suck the air through the radiator but press it out of the engine bay thus neutralizing the air stream of the external fan.
That‘s the only thing I can imagine how it can come to that kind of overheating in the car but not on a stand.

@Geoberni,

The workshop that has to do the testing is the most expierienced and best reccomended in whole Germany. They are absolutely and very sorry for all the complications and have assured me to cope for all related costs with exception of my conrods. So far so good, but I‘d like my car back in good running condition even if it takes some time.

Chris