Thread: Coolant leak 300tdi

I have a coolant leak, drip really, coming from where the top radiator hose attaches to the thermostat housing. The drip seemed to be leaking out of the side of the hose rather than from the bottom of the hose. I replaced the old original hose with a new one but same problem. Funny I thought. I replaced with yet another new hose and sure enough drip drip.

I had recently removed rad for cleaning and rodding, had no previous problem.

I returned to radiator repair shop in the hope they may shed some light. His first thought, hose was porous and therefore leaking. Didn't explain new hose dripping. He pressurized system and sure enough drip drip again. On examination he thought the problem was caused by the two pronounced ridges on thermostat housing from manufacture (presumedly cast) Sure enough there were corresponding low spots inside hoses where the ridges had dug into hoses. Failure to put old hose back in exactly same spot caused drip. Still didn't explain new hose problems but they were aftermarket and seemed lighter thinner than original.

I will grind down ridges today and see how it goes. Anyone else come across this??

Originally Posted by workingonit

Having same problem on my Disco 1. Have ordered new hoses as current ones are probably due for replacement anyway. Thanks for the heads up and will check if casting lines are the problem when I change hoses.

I would be very interested to know. It's easy enough to remove ridge lines, I used a Dremel. Time will tell if it works.

Pete