Over heating possible water pump fail.

[Mike J]

Hope someone can help. To celebrate rebuilding the steering rack and fitting the new Weber vacuum tank I took the stag for a test drive. within 6 miles the temp guage was over half way, in another mile was in the red. I've never had these problems before. The Kenlowe dutifully kicked in but didn't help. I drained the sytem. flushed it and fitted a new 88 thermostat. Still overheating. I had topped up with BP 97 thinking it was that burning to hot. Drained fuel and replaced with 95 still overheating. I had a new 12 vane pump from Rimmers fitted about 5 years ago. Hope it isn't that but can't think what else it can be. Any advice greatly appreciated. Mike

[Andrew S]

If you remove the radiator filler cap before the engine gets hot, you should be able to see water flowing, if not then there is nothing pumping it.

[Mike J]

Thanks Andrew. But will it be flowing if the thermostat is closed.

[Andrew S]

Slightly but if run the engine from cold until the stat opens slightly, it will be obvious

[Mike J]

Will give it a go. (Only because you have a yellow one as well.) If there is no flow will I need a whole new unit? I suppose I will need to strip it down to find out. Think I might switch to an electric one if it needs changing.

Mike

[Andrew S]

Has this suddenly come on? What temperature does she usually run at? Is there water coming out of the overflow bottle? Does the engine really feel hot when you lean over the engine compartment? I say this in case the temp sensor is failing and over reading. Thinking aloud here but I am sure others will have other suggestions too

[Mike J]

Normally runs at about 1/3 up the guage. No water coming out of bottle. Pipes to and from rad not as hot as I would expect. Only just started to happen though hasn't been used for 5 months. Mike

[Mike Stevens]

See if you can get hold of an infra-red thermometer, (one of these gun type things). Then you can check the temperature of various things to see if it really is getting hot, or the gauge is reading high.

Could the fuel gauge also be reading high? It uses the same voltage stabiliser as the temperature gauge does.

Cheers,
Mike.

[fedex]

had a similar problem, my gauge went up over half way when I turned the ignition on. changed the sender on the side of the engine (two minute job) and all was back to normal. I know it does'nt sound the same as your problem, but may point you in the right direction, cheers roger

[Paul Goldsmith]

Pipes to and from rad not as hot as I would expect

Sound either the sender is playing up or, given that the Kenlowe also kicked in, the thermostat has stuck in the closed position (did you test your new 88C stat first ?)

As even with no pumping flow the top pipe would get too hot to hold through convection alone ?

[Mike J]

Checked the thermostat before fitting. Just been out in it again. Temp fluctuates. Almost going into the red then slipping back to vertical. There is intermitent flow looking into the top of the rad. I wonder if the 12 vane conversion (5 years ago by the engine rebuilders) used the correct housing and over time the nut on top of the pump has slackened. Not sure as never worked on this type of pump before. Paul the sender is about 2 yrs old and has been checked. Mike

[Andrew S]

The good news is that this cant be engine and has to be electrical. Could be your gauge.

[Mike J]

Thanks Andrew, one thing though the Kenlowe kicks in around 3/4 hot and there is no obvious flow in the radiator. Mike

[Mike J]

The problem may be that a 12vane pump was fitted by PO but using a 6v housing. Is there an easy way of telling if you have a 6 or 12v housing. They look the same in the rimmer catalogue Mike

[Andrew S]

Thinking about it, the car was fine until you used it recently after 5 mths, if I'm correct. So, can't be the wrong pump etc.