Thread: I hate plastic radiator tanks and bits

Hi Ballbag. I think Mario had in mind a nut attached to a threaded brass take off point. So tapped hole and thread protruding on inside of tank and then a nut to suit so you have the double whammy of brass into threaded plastic and retained and supported against movement by the nut. High pressure plumbers tape would work in that scenario as long as nut and insert was not able to back off.

That would probably work but given how thin the wall was I was happier just using a fairly low mileage and good quality tank that I had here. If I didn't have the spare tank I would go threaded insert and nut and it would probably be ok. The concern I have with just insert and no nut is the likelihood of movement from weight of brass and rubber hose over time and wearing the hole. The disadvantage of the nut is you remove the tank to do it properly but it's not a bad job if you have long clamps to put pressure on tank and rubber seal.

Cheers

We have a range of D2s in the family - 3 V8s and 5 TD5s.

6 of them have had replacement of that %$%$^% pipe at the top of the radiator. We have used a small male thread barbed hose spigot similar to the suggestion by Mario.

Radiator pressure should not exceed about 20 psi, so I believe that the method of fixing - by drilling and tapping the hole left by the snapped tail and the use of a thread sealant when installing the barb - is a very satisfactory solution and proved to be more than adequate.

Of course, the repair should include an assessment of the thickness of the damaged area and its suitability to safely drill and tap.

Our experience has been that a 1 hour, in place repair is the way to go as long as the remainder of the radiator is in good condition. Possible floating plastic swarf can be flushed out of the system by applying judicious water pressure to the top hose and swamping any plastic away.

Replace the stupid nylon pipe with suitable rubber hose and worm drive clamps while you are doing the job.

Hope this helps.

Pete