Thermostat housing issues

[toddao]

Thanks once more for replies. The saga unfortunately continues.

I tried to drill out the bolts from the out-wash tank, by centre punching them then using a pillar drill, but I couldn't hold the tank firm in anyway so I shafted that as well. Seems those old bolts are so hard that the drill prefers eating alu!

Fortunately another tank was available from Citroen this morning. Now I'm looking at the new cover and it has two extra outlets compared to my old one. With it, however comes the parts to block them but then there's the extra problem of it having no bleed screw.

The question is - do I need this bleed screw or is the one in the radiator enough? If I do need it, then I'm going to have to run a tap I suppose and I'm a bit wary of drilling the nice new casing. Is there anything I must look out for before I destroy the new case?

Here's a pic from this morning outside the Citroen ( and other exotica) dealer. It was funny going with the wife. She had a look at the Ferraris and said : I can't believe you pay all that money then only get two seats!

[jonathan_dyane]

Well done managing to get the new casing, I am surprised it was still available!

I would certainly drill and tap the new casing for the bleed screw, IIRC the casing you now have was fitted to Visa and 205 diesel's which had a header tank and were better to bleed, without it I don't think you will manage to get the air out on the BX; if you centre punch it it will be very straightforward. A pillar drill is best, but if you have a steady hand there is no reason why you shouldn't be able to drill a suitable hole with a hand-helf electric drill and tap it, but make sure you use the correct drill bit size (refer to here: http://www.simetric.co.uk/sidrill.htm).

If you're not feeling confident, a small engineering firm will do it for you for a very small fee I'm sure...

[jonathan_dyane]

Or alternatively, if you are really desperate to get it up and running, you could always fit the new thermostat wedged open with a couple of aspirins and bleed it with one of the temperature sensors...

Don't forget loads of copper grease on the bolts and in their threads!

[MULLEY]

Top piccy that

[docchevron]

Ah, see, the stat housings that dont have the bled screw in them had a bypass hose from the rad to the front of the stat housing with a bleed screw in the hose.

That said the casting should be the same so you could just drill a hole through it, tap it and stick a nice brass bolt in with a flat cut in one side of the thread (not all the way up) so you can bleed it without having to completely remove the bolt..

Agree, top piccy!

You're wife's logic is spot on too!

[toddao]

Thankyou for replies, almost there now. I went this morning to my friend Heinz who has a small workshop in his cellar.
He drilled and tapped for the bleed screw - no problem. What was more time consuming was removing the circlip that holds the thermostat - this was completely rusted in there. There was no way that even a very good pair of circlip pliers was going to move it, or gently tapping it after soaking it in penetrating oil.
We had to grind into the sides of the old casing then tap the clip out this way. Good luck anyone who has to do this in situ if more than twenty years worth of water has done its work!

Heinz also managed to grind my ears with his self-made CD compilation of German beer drinking songs played too loud, too early on a Sunday morning!

[mat_fenwick]

You're wife's logic is spot on too!

Well, she married a BX owning dude, so she's obviously got sense...

[toddao]

That's very kind Mat! When she married me though, I didn't have a BX yet, just a 1979 Honda C-50 step through. She was drawn to the wild biker image I suppose! Either that or she thought she could get a discount on Pizza deliveries.

[CitroXim]

Heinz also managed to grind my ears with his self-made CD compilation of German beer drinking songs played too loud, too early on a Sunday morning!

The things we have to endure for our love of Citroens