10 replies to this topic

[thefarmer]

Cooper 1275 carb
1991


What is the best way of checking to see if the water pump is functioning correctly?

Also...if it is faulty, how do you replace it? Any tips?

thnx

[armotorrepsirs]

Cooper 1275 carb
1991


What is the best way of checking to see if the water pump is functioning correctly?

Also...if it is faulty, how do you replace it? Any tips?

thnx

What makes you think the water pump is not working?

thanks Aaron

[turbominicooper]

take of the hose connected to it and see if water pass's through.

if you want to replace it a high capacity one is only £12 or so, 4 x 11mm bolts and its off..., simples

[thefarmer]

Cooper 1275 carb
1991


What is the best way of checking to see if the water pump is functioning correctly?

Also...if it is faulty, how do you replace it? Any tips?

thnx

What makes you think the water pump is not working?

thanks Aaron

basically, it's on a list of possibles for causing the engine to overheat damn quick. head gasket, timing has been swapped/changed etc. New rad cap is on it's way, so that will be another test (before i try any water pump activity). The mixture may be out...i've read that if it's too lean, that can cause overheating. The only other thing i can think of, is to flush out the radiator.

[Boycie]

If the waterpump is being driven by the belt, I'd say it's 'probably' working sufficiently well to stop the engine overheating.

The only time this can be proved wrong is when the impellor that sits in the coolant splits/ breaks or becomes loose on the pump spindle. However, Mini pumps are really not prone to this, French cars/ Fords/ Vaux's etc (normally with plastic impellors... yes really..) are but this is unlikely to be a problem.

A blocked rad is quite likely if coolant changes haven't been done every few years.

It's normally the bottom half the clogs with debris, so after a run CAREFULLY feel around the bottom of the rad- if it's not as hot (or even cold) as the top of the rad, it needs changing/ reconditioning.

[thefarmer]

If the waterpump is being driven by the belt, I'd say it's 'probably' working sufficiently well to stop the engine overheating.

The only time this can be proved wrong is when the impellor that sits in the coolant splits/ breaks or becomes loose on the pump spindle. However, Mini pumps are really not prone to this, French cars/ Fords/ Vaux's etc (normally with plastic impellors... yes really..) are but this is unlikely to be a problem.

A blocked rad is quite likely if coolant changes haven't been done every few years.

It's normally the bottom half the clogs with debris, so after a run CAREFULLY feel around the bottom of the rad- if it's not as hot (or even cold) as the top of the rad, it needs changing/ reconditioning.

right....
in my neverending quest to resolve my overheating problem (seems there are a few people that have this), i have now reversed flushed the rad. Much improved now, and the temp seems to be more stable. Still slightly over the half way, but it seems to stay there or come down.
Still haven't received my new rad cap though....

One thing i noticed is that after driving the car around for a while (so the temp gauge is showing just above the halfway stage) and then i park up and switch the engine off...that is now when the overflow pipe will start to drip. Only a little though..but that is when it drips. It used to do that when driving as well.

Is that an improvement? )


any insight would be appreciated.

thnx

[jkjaxor]

i used to have a problem with my car overheating, changed my pump, flushed the rad and changed the cap. some caps are longer than others, so make sure the spring on your cap is long enough to let the rubber seal of the cap seat in the radiator.
if the rad overflow drips wait until the car is cool and check how much water is in the radiator. the water level should just cover the fins, then there is enough room for expansion, if the water level is lower, you have a leak or the system is at to high a pressure for the cap.
also it will be obvious if the pump is on its way as you will usualy hear the bearing whirring as the engine speeds up or slows down, oyu can test this by listening for a different sound with the pully belt on and off.
jack

[frenzy382]

i used to have a problem with my car overheating, changed my pump, flushed the rad and changed the cap. some caps are longer than others, so make sure the spring on your cap is long enough to let the rubber seal of the cap seat in the radiator.
if the rad overflow drips wait until the car is cool and check how much water is in the radiator. the water level should just cover the fins, then there is enough room for expansion, if the water level is lower, you have a leak or the system is at to high a pressure for the cap.
also it will be obvious if the pump is on its way as you will usualy hear the bearing whirring as the engine speeds up or slows down, oyu can test this by listening for a different sound with the pully belt on and off.
jack

did you get your new rad cap?

Edited by frenzy382, 29 June 2010 - 05:29 PM.

[thefarmer]

i used to have a problem with my car overheating, changed my pump, flushed the rad and changed the cap. some caps are longer than others, so make sure the spring on your cap is long enough to let the rubber seal of the cap seat in the radiator.
if the rad overflow drips wait until the car is cool and check how much water is in the radiator. the water level should just cover the fins, then there is enough room for expansion, if the water level is lower, you have a leak or the system is at to high a pressure for the cap.
also it will be obvious if the pump is on its way as you will usualy hear the bearing whirring as the engine speeds up or slows down, oyu can test this by listening for a different sound with the pully belt on and off.
jack

thanks for the info.
I'm not aware of any whirring that goes up or down with the engine, but i'll give it a go.

I've checked the amount of water that is in the rad after it has cooled down, and it is just at the fin level..i think it might have alost very tiny bit whilst dripping out.
I'll wait for the new rad cap to arrive and see what happens before i take anything else apart....so far i've managed to put everything back that i've taken off, but it will only be a matter of time before i really mess something up!! )

thnx

[thefarmer]

i used to have a problem with my car overheating, changed my pump, flushed the rad and changed the cap. some caps are longer than others, so make sure the spring on your cap is long enough to let the rubber seal of the cap seat in the radiator.
if the rad overflow drips wait until the car is cool and check how much water is in the radiator. the water level should just cover the fins, then there is enough room for expansion, if the water level is lower, you have a leak or the system is at to high a pressure for the cap.
also it will be obvious if the pump is on its way as you will usualy hear the bearing whirring as the engine speeds up or slows down, oyu can test this by listening for a different sound with the pully belt on and off.
jack

new rad cap has arrived and it has been put on. Took the car for a thrash and no dripping whatsoever (overflow pipe is dry as a bone) and no reduction of coolant either.

The temp gauge seems to settle to just above normal/halfway point. At it's worst it got to 3/4 and then came back down again.

Not sure if that is ok or not..but if it is, then i'm happy.

Can anyone tell me if the temp gauge reading just above normal is ok?

thnx

[Boycie]

Well the new cap has stopped the leak.. so you're halfway there!!

That temperature sounds 'about' right.

In an ideal world, the temp would sit dead in the middle, whether you're sitting in traffic or cruising along a motorway. However, this is a Mini and things aren't that simple!! The temp transmitter and gauge are not particularly accurate and as long as the car doesn't visably overheat or boil over, I'd say you're now fine.

If it's any help, my car sits just over halfway at the moment, in heavy traffic in town yesterday the needle went 3/4's up.. but it coped ok.