15 replies to this topic

[huw_jenks]

1979 Mini 1000, 1293, Cooper S head, HIF44, water heated inlet manifold, new radiator (not sure what radiator, but it is quite a good one).

Right, the problem I've got is that coolant is leaking from somewhere in the engine bay, like I said in the title, and the problem is that I can't find where. It has been doing this for a while and after fixing different pieces it would start leaking from somewhere else, and now I can't find where it is coming from.

First it was the heater valve. I replaced this a couple of times, but it kept leaking. After filing away at the bottom of of the valve and sanding the top of the head a bit I seem to ahve a good seal and the gasket is fine. Then water was leaking from the hose on the valve, but some insulation tape and a new jubilee clip fixed that. I also noticed two kinks in the pipes that could have been restricting flow, one between the manifold and bottom hose, and one between the heater valve and the heater, in the cabin. I worked these into a better shape and put cable ties around them to stop them kinking.

The next palce that water was coming out of was the water pump itself. So I took out the radiator, fan, water pump, cleaned up the mating surfaces and put it back on. I didn't have a gasket for the water pump, and could't be bothered cut one out from gasket paper, so I used some silicon sealant from a mechanic I know down the road.

Now there is still water coming out of somewhere. It is going all over the engine bay, but only when I am driving. When the car is stationary (even after it has been driven) no coolant is visibly leaking. The gasket on the heater valve looks okay, even though there is water all over the engine bay. As I am driving there is water visibly spraying up out of the right hand edge of the bonnet, and leaving rusty marks on the bonnet.

Has anyone got any ideas where this water could be coming from? At the moment it is just an annoyance, but it's going to start freezing soon and putting new antifreeze into the engine every time I top it up is going to be a real pain...

Thanks

[mars red mike]

If water is being sprayed all over the engine bay I would say that the water pump is knackered, leaking or both. Either that or the sealant that you used isn't good enough.

[Sprocket]

http://www.caraircon...u...t=10&page=1

Edit* this might not help as by the sounds of it the whole engine bay will light up

Which right hand are we talking about? when you are sat in the car or when you are standing at the front of the car looking at the engine?

If its the heater valve end, I would be looking at a split hose, as when you are driving with the engine doing some rpm, the pressure behind the thermostat in the block and head is fairly high, at idle it wouldnt be anywhere near as high.

One option is to take the bonnet off and then go for a drive on quiet roads then you will be able to see roughly where its coming from.

Could be a core plug perhaps

Edited by Sprocket, 26 November 2009 - 06:36 PM.

[huw_jenks]

Which right hand are we talking about? when you are sat in the car or when you are standing at the front of the car looking at the engine?

When I said right hand side I meant offside, so right hand side when in the drivers seat. Which is why I suspected the heater valve gasket but it seems to be good.

If its the heater valve end, I would be looking at a split hose, as when you are driving with the engine doing some rpm, the pressure behind the thermostat in the block and head is fairly high, at idle it wouldnt be anywhere near as high.

When I've had the bonnet open looking for the leak I have been revving the engine (using the throttle spindle, not my leg, that would be difficult) so I thought that would show up where the leak is coming from, but clearly not...

One option is to take the bonnet off and then go for a drive on quiet roads then you will be able to see roughly where its coming from.

I may try that, but I'll have to wait til it stops raining... Which could be weeks.

Could be a core plug perhaps

And I have no idea what that means...

[biggles1293]

1979 Mini 1000, 1293, Cooper S head, HIF44, water heated inlet manifold, new radiator (not sure what radiator, but it is quite a good one).

Right, the problem I've got is that coolant is leaking from somewhere in the engine bay, like I said in the title, and the problem is that I can't find where. It has been doing this for a while and after fixing different pieces it would start leaking from somewhere else, and now I can't find where it is coming from.

First it was the heater valve. I replaced this a couple of times, but it kept leaking. After filing away at the bottom of of the valve and sanding the top of the head a bit I seem to ahve a good seal and the gasket is fine. Then water was leaking from the hose on the valve, but some insulation tape and a new jubilee clip fixed that. I also noticed two kinks in the pipes that could have been restricting flow, one between the manifold and bottom hose, and one between the heater valve and the heater, in the cabin. I worked these into a better shape and put cable ties around them to stop them kinking.

The next palce that water was coming out of was the water pump itself. So I took out the radiator, fan, water pump, cleaned up the mating surfaces and put it back on. I didn't have a gasket for the water pump, and could't be bothered cut one out from gasket paper, so I used some silicon sealant from a mechanic I know down the road.

Now there is still water coming out of somewhere. It is going all over the engine bay, but only when I am driving. When the car is stationary (even after it has been driven) no coolant is visibly leaking. The gasket on the heater valve looks okay, even though there is water all over the engine bay. As I am driving there is water visibly spraying up out of the right hand edge of the bonnet, and leaving rusty marks on the bonnet.

Has anyone got any ideas where this water could be coming from? At the moment it is just an annoyance, but it's going to start freezing soon and putting new antifreeze into the engine every time I top it up is going to be a real pain...

Thanks

I had the same problem with coolant going over the wing, turned out that the rad had split at the filler neck, water only came out under load, I then replaced the rad, started doing it again but not on the same scale, then realised that there was no overflow pipe attached, now there is..Bingo..fixed!

[mk3 Cooper S]

Bypass hose??

[Sprocket]

Bypass hose??

Never knew there was a bypass hose on the drivers side of the engine

[alicetheauto]

I was thinking bypass hose, only kicks in when the engine is warm ie driving, and if it is split at that side it could ossibly spray over to make it look like its on the drivers' side? Perhaps try a new waterpump (only a few quid) and a new bypass hose at the same time? Only coolant on that side of the engine is in the heater valve, which you reckon is ok?Unless its the waterway in the head gasket (unlikley?) or a core plug (one of the round plugs in the engine itself, used to block up manufactuing holes from when the engine was cast).

[mk3 Cooper S]

Bypass hose??

Never knew there was a bypass hose on the drivers side of the engine

THERE ISN'T

[Sprocket]

Bypass hose??

Never knew there was a bypass hose on the drivers side of the engine

THERE ISN'T

That I do know

[huw_jenks]

Thanks for the replies, I think I found at least part of the problem, but discovered another one...

I'm not discounting a leak from the bypass hose or water pump (water could be going onto the fan or belt and spraying over the engine?) but I have found one leak for definate due to serious retardation on my own part. It seems that after putting the head back on the block and torquing it down, I forgot to re-torque it after doing some miles (some say 100, some say 500 which is closer to what I have done). So coolant was coming from between the head and the block on the drivers side of the engine. I don't think the head gasket has gone (no mayonaise on the rocker) so I borrowed a torque wrench and began doing the nuts up to 68 Nm.

To cut a long story a bit shorter, three of the studs are have had the threads stripped. On the front of the head, bolts 1, 3 and 5 starting at the radiator end. The bolts under the rocker cover torqued up fine, as did two on the front, but three of them were just spinning.

I took them out and the thread has definately been stripped on two, the third looks allright which I suppose means that the thread on the block will be strippped? I took the torque wrecnh back to my neighbour and showed him the bolts. He noticed that the nuts were all the way down to the bottom of the thread on the top of the bolts and said that could be why they were spinning and the thread in the block might be okay.

I also need people to confirm what I am thinking.. I really shouldn't drive my car with three studs missing right?

And also, there are a couple of car parts places in town not too far from me, would they be likely to stock the bolts I need? I don't seem to have any spare...

[Guess-Works.com]

What you need is a pressuriser, years ago ( talking about 20 years ) my mini got a little hot, pulled over and called Mr AA... He came along put some water in and pumped up the system with what was essentially a bike pump attached to where the radiator cap goes... This showed a very fine spring of water from my water pump...

Without that I'd have been looking for the cause for ages...

[James182]

What you need is a pressuriser, years ago ( talking about 20 years ) my mini got a little hot, pulled over and called Mr AA... He came along put some water in and pumped up the system with what was essentially a bike pump attached to where the radiator cap goes... This showed a very fine spring of water from my water pump...

Without that I'd have been looking for the cause for ages...

These are still available but the ones i hve seen are relatively expensive. i think sykes pickavant do one still. i had a water leak and could not find it for ages!!! turned out it was two things......One of the jubilee clips on the bottom hose was mishapen causing the hose to be mishaped aswell therefore leaking from there....the other was a split bypass hose...i proceeded to use a reinforced silicone part and havent had the problem since!!

[huw_jenks]

So the bolts I need to keep the head down, what are they called? And how likely is it that I can get hold of some from non-Mini specialist places?

[Minitrio]

Also had a similar problem, found out after a week of hunting, that the shaft seal on the waterpump had gone. Basically it was leaking straight onto the auxillary belt and spraying everywhere. Fitted new water pump and no more leak!