Volkswagen Owners Club Forum banner

1 - 4 of 4 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter #1
My diesel rabbit is over heating. I've replaced the thermostat, the thermoswitch, and the radiator and still it overheats. I disconnected the top radiator hose and tried topping it off with coolant a few times to make sure there was no air pocket. It seemed the fan was not always turning on. I tested the fan motor (it works), I bypassed the thermoswitch (the wiring works). So I thought, ok, bypass the thermoswitch till you figure it out, but it's still overheating even with the fan running constantly. So now I look for advice as to what else I could try.

Possibly important to note. The overheating all started after running the car on grease (I have a greasecar system installed), the purging system busted on me so I had to start the car up with grease still in the fuel lines. Bad for the pistons, the car did not start overheating right after this incident, but soon after. Any ideas appreciated. My mechanic is great, but I can't afford that right now!
 

·
Super Moderator
Joined
·
10,514 Posts
Take the res cap off when the car is cold, securely fasten a latex glove over the res fill. Start the car and if the glove immediately inflates, blown head gasket.

Next test is to take the res cap loos to bleed residual pressure, replace the cap start the car, in 30 seconds remove the cap if there is another release of air, bad head gasket.

Other than that you may have a loose belt, bad water pump, or you need to throughly flush your coolant system.

Remove the thermostat and reconnect the cover and the hose.

Break the hose connection at the front upper hose at the block.

Stick a water hose running full in the hose so that all the crap is forced out of the block to run clear, then reverse it and insert the hose into the upper hose flange on the block so that the crap now comes out of the radiator upper hose.......

Do this about 3 or 4 times till all the water comes out clear.

On the edge lip of the thermostat drill a 1/16 hole insert it so that the hole is up in the unit, this prevents a air bubble when you fill it.
 

·
Registered
Joined
·
4 Posts
hello... hey that nifty latex glove technique your talking about...is that limited to a volkswagen ? thats incredibly clever... i have a buddie....his truck...we think its a head gasket...would the glove tell us anything ?
 

·
Super Moderator
Joined
·
10,514 Posts
Probably,, most radiator shops can test the anti-freeze for suspended exhaust gasses..... another good indications are are your coolant lines pressurizing there you can't squeeze them?
 
1 - 4 of 4 Posts
Top