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Problem fitting rear drain tube to inlet manifold on BT7

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fishyboy

Jedi Hopeful
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Hi all,

Following a recent post about rebuilding by HD6 carbs (https://www.britishcarforum.com/bcf...llow-on-questions-from-HD6-carburetor-rebuild) I have been trying to fiit new drain tubes to the inlet manifold on my BT7. I have been able to fit the front one with no trouble, but I have been unable to remove the old nut from the rear one (it just seem to spin round). Off course I now realise that air is getting though the old drain nut and leaning the mixture on my rebuilt carbs.

As a stop gap, untill I can think of a way of removeing the old nut (without having to take the manifold off), I am wondering whether I could block of the hole in the nut and at least allow the carbs to be set up correctly. Is this sensible?

Phil
 
Well if it is spinning around this may suggest the male part has stripped threads. ?

OH Sure plug the hole.
 
I wouldn't run with the hole(s) plugged for too long. The holes are there for a reason (the BMC beancounters wouldn't have allowed the installation of extra holes if not absolutely necessary). If you're running rich--like cold engine, chokes full on--gas will puddle in the manifold (this is sometimes called 'wall wetting') and you'll either be washing the oil off the cylinders causing extra wear or, worse, could get some nasty backfires and possibly even a fire.

I've started a cold engine, chokes full on, then shut down after a few minutes. There's usually a couple of not insignificant puddles of gas under the drain tubes.
 
Get the car up in the air , Reach up underneath with a set of vice grips , clamp onto the stub in the manifold unscrew while pulling and it should come out . Now you can see if the fitting or the manifold is stripped and then decide how to fix it .
 
fishyboy said:
Hi all,

Following a recent post about rebuilding by HD6 carbs (https://www.britishcarforum.com/bcf...llow-on-questions-from-HD6-carburetor-rebuild) I have been trying to fiit new drain tubes to the inlet manifold on my BT7. I have been able to fit the front one with no trouble, but I have been unable to remove the old nut from the rear one (it just seem to spin round). Off course I now realise that air is getting though the old drain nut and leaning the mixture on my rebuilt carbs.

...
Click to expand...
Did you remove the carbs to get to the rear one? That's what I would do.
 
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