Some simple fixes I tried before going further were:
1. Trying a new cap - as it might be releasing less than 1bar.
2. Remove the thermostat.
3. A pourus radiator.
4. Air in the system - so filled it up by the rad.
5. Back flushed the radiator.
6. Pressure tested the entire system and looks for leaks. These may be drawing in air.
After a bit of investigation it turned out to be the dreaded head gasket. To explain in more detail, the water was building up a pressure into the coolant system slowly as I drove. When it reached 1bar, the limit on the cap, it blew about a litre out the back of the tank.
A diagnoses I easily reached by taking the cap off > replacing it > then holding the main coolant hose and revving the engine from the bonnet area. I could feel the pressure build up my hand but didn't see it blow out the cap (which it did after about 30mins of driving). There was also
small bubbles coming through into the reservoir. I certainly couldn't afford a dealer to do it and most garages said no chance when I mentioned the problem.I've never done a cambelt before (brakes and oil pumps were my previous best!) but was willing to try, so I bought a Brookes workshop manual and did as much research as I could.
I got some morale support from a friend who is mechanically minded (the picture says it all) and off I went:
Some things I learnt along the way:
- Plan to get it skimmed 'well' in advance. It's not always the 1/2 day job they tell you!
-Leave the lower cambelt cover on if you can. The belt can the manoeuvred out.
-Mark the cam belt pullies with tipex for peace of mind. If you leave the drill bit in the injection pump not a lot can go wrong. PM me if you need to know how to find the flywheel mark. ]
- Check the weather before starting. I did it on my mothers drive and after horizontal rain had to go to B&Q to buy a plastic sheet (£2), aka roof.
- Hit the dampener pulley off with a piece of wood and a hammer if it's stuck.
- Clean (and I mean clean) all the edges with a scalpel blade until spotless.
- Take photos of all the electrical connections. I forgot where some went after a week and had to resolve problems with earths and immobilisers going off.
- Leave all the injectors loose when trying to start it and do them up when it does to bleed air out.
I can write loads on this but as they say .. a picture says a thousand words:
4 comments:
Hey I'm trying to diagnose a water leak on my 1.9TD T4 and I have the same symptoms as you had...
I have to bleed air out of the system every morning and top up with water/coolant... not much just enough to be annoying.
The engine never overheats, doesn't have any gunk in the oil, and has been losing coolant for roughly the past 1500 miles. I keep topping her up / bleeding out air and she's still going.
I've spotted a small leak in a hose that goes into the oil cooler (next to the oil filter) and am about to replace that but if that doesn't work I'm gonna have to look at the head gasket.
When you had this problem did your van overheat or show any other symptoms of head gasket problems... (white smoke, yellow mayo in oil etc?)
If you have any advice on what it could be before I go taking it to bits (there's absolutely no way I can afford to actually pay someone to do it...) I would be most grateful.
Your van looks ace btw
Dave
davebuttis@gmail.com
Hi, emailed a reply - hope you got it.
I know its been a while since you did your head on the VW
Im acutally doing the same thing
i need to change the head gasket an doing it on my own, with the exhaust manifold how did u get the nuts off ?
also cam bolt Ive used rattle gun, large breaka bar ? I do need some info i cant find anything on the net
would like to get some help if possible thanks
joe
Post a Comment