Heater tap dissection

Vanny · Post by **Vanny** » Mon Mar 19, 2012 9:52 pm

As part of a concerted effort to get the BX back on the road, the weekend saw not one but three heater taps dismembered! Ultimately it was quite easy to rebuild, but the faults where caused by a build up of RadWeld /KSeal.

Check out the full description here

KevR · Post by **KevR** » Tue Mar 20, 2012 9:32 am

I've had the same problem in the past - as you say, quite easy to rebuild, the tricky bit being getting the damn things on and off the car. None of the ones I've done has had quite that volume of crud in though!

toddao · Post by **toddao** » Tue Mar 20, 2012 10:38 am

Yes, how exactly do you get them off in the first place? I think I need to do this operation, mine is stuck fast.

Mickey taker · Post by **Mickey taker** » Tue Mar 20, 2012 12:38 pm

mines fine

Mike E (uk) · Post by **Mike E (uk)** » Tue Mar 20, 2012 1:28 pm

Radweld is awful stuff. When added to dirty coolent it can block up engine waterways, as well as BX heater valves.

I suspect it would never be needed if people would change their coolent at sensible intervals.

The antifreeze works to stop freezing for much longer than it keeps its anti corrosion properties.

The newer long life stuff should be better though.

Vanny · Post by **Vanny** » Tue Mar 20, 2012 3:07 pm

Well in my case i drove 11 miles with a burst coolant pipe, while towing another car, mostly up hill. In fact the car only stopped because the battery ran out having been on max fans with a dodgy alternator. She did manage another 1000 miles on the rad weld though.

As a useful tip, the brass tubes are peened over at both ends to hold the body together. You need to pull these apart which takes a scary amount of force. You would be well advised to drill holes through the flanges around the case join so that you can bolt the two halves together after rebuild. I suspect alot of swear will ensue if you drop the damn thing mid way to refitting!

Way2go · Post by **Way2go** » Tue Mar 20, 2012 6:23 pm

My heater valve was slightly hesitant to move a few years ago but because an overheating issue occurred which was cured by running Barr's Professional flush for a few days, the tap was easy to move again too.

That crud looks a bit excessive but I wonder if it would dissipate in situ under such a flushing product as Barr's?

(I suppose though you don't want to engine flush if you know you have leaks?

)

JayW · Post by **JayW** » Tue Mar 20, 2012 6:33 pm

I suppose the main reason it collects there is as the water flows out of the matrix the bottom of the tap is the lowest drop point in the connection as the pipes climb again outside the bulkhead. Particularly when the engine gets switched off and the particles in the matrix side settle to the lowest point.

Doesn't say much for the bottom of the rad!

Mind you, least that doesn't get the constant packing down like the heater tap does.

citronut · Post by **citronut** » Tue Mar 20, 2012 7:41 pm

the one i did many years ago i drilled the tubes out,

regards malcolm

kiwi · Post by **kiwi** » Tue Mar 20, 2012 7:57 pm

toddao wrote:Yes, how exactly do you get them off in the first place? I think I need to do this operation, mine is stuck fast.

The TZS has gone that way as well and I suspect that is the cause (as in a blockage) which is causing the irractic pressure in the sytem giving the impression of another HG failure.

When they replaced the HG the radiator leaked so they bunged in some radweld, years later punishment.

The TRS when I changed the Antifreeze mix same thing happened with the interior matrix, it sprung a leak. When you clean the cooolant watch out for leaks and yes sadly radweld goes in to bung those leaks.

As for the TXD thats been sweet and obviously well looked after by previous owner, my only concern at present is service is going to go over I parked up with 180,000miles yesterday (service due) and have a long trip planned tommorrow (thursday), ironically using that trip to get the servicing gear as well. pre-winter service antifreze check as well