Leaking Coolant

[cox]

Hi,

I have an 8 valve 1990 GTI and I am having a problem with leaking coolant. I followed the cooling system round and managed to find that the coolant was leaking between the connection to the water pump and the hose that connects to the bottom of the radiator.

A fair amount of coolant was present around the bottom of the join with the hose. So I had a look at it with my brother and he recommenced to swap the old clip for a screw fastening type clip which i managed to source from halfords. This didn't fix the problem. The hose also looked pretty warn, so i tried replacing that. I left the engine running for a good 20 minutes after topping up the coolant levels and left a bowl underneath the leaking area over night. In the morning the bowl was completely bone dry. So I was quite pleased with myself, thinking I had fixed the problem. I hadn't. The car is still leaking coolant from around the same area. So either it is leaking through the hose connection (which I would hope not after new clips and hose) or the coolant is just conregating at the seal of the hose and is leaking from the seal of the water pump. I took a picture just now before it got dark and I can see there is some moisture on the metal that joins the plastic of the pump. Now I am no mechanic but i know that gravity tends to pull matter downwards and I am staring to think it is the pump that is at fault. Here is the picture:



If anyone has experienced a similar problem or has any ideas then please let me know. It looks like the plastic nozzle the hose connects to is bolted to the pump. Can i just get this replacement plastic part or will i need a whole new pump unit?

Many thanks,

Dave.

[nealey]

Thats the thermostat housing which is available seperately, be careful when tightening it up after replacing it as it is plastic and overtightening it can crack the housing

[Leon R]

2nd what Nealey said plus when you take the thermostat housing off, theres the thermostat plus a seal that you should also change as the thermostat will fall out.

[Goops]

Hi,

I had a similar problem when I replaced the water pump..agree with the others, check you put a NEW seal in the waterpump (use a sealant as well) and definitely change the thermostat housing, you can get it from VW spare parts outlet.

Thanks,
G

[dubslug]

look like the housing is cracked in the pic, change it

[cox]

Thanks for the feedback everyone. I'll post back to let you know how i get on.

Thanks again,

Dave.

[Mr Blue]

change the thermostat while your at it mate

 

[cox]

Hi,

I had a similar problem when I replaced the water pump..agree with the others, check you put a NEW seal in the waterpump (use a sealant as well) and definitely change the thermostat housing, you can get it from VW spare parts outlet.

Thanks,
G

maybe a stupid question, but can you recommend what sealant I would use?

Thanks,

Dave.

[Goops]

Hi Dave ,

The one i used was called "Loctite black superflex sealant" picked it from the local spare parts shop. I am sure a mechanic/some1 more qualified could recommend something better! 

Just get thw waterpump/thermostat done job done coz it eliminates something you will eventually have to do anyway!

Goops

[mattkh]

Hi
I would not use the sealant.
Any excess sealant inside the housing could come off and lodge itself in the thermostat.