Inlet manifold internal coolant pipe

Hi all - am in the middle of a rebuild at the moment (aided by someone much more experienced than me thankfully!). The heater pipe that goes all the way through the manifold itself (appears to be part no. 90611532) is rusted through in many places, but is good and stuck where it comes out of the manifold and won't budge. I've tried heat, mole grips, you name it. From the photo on Rimmer Bros, it appears to be a 'normal' thread, but maybe they've threadlocked it or bonded it as well in some way - couldn't find any suggestions on how to get it out but appreciate may just be crap at searching. Any suggestions? The guy helping me says not to worry about it but I'd love to swap it out if there's a way to do it without trashing the manifold!
Sorry, I should mention I did find this thread a while back by @74westy for which my thanks - sadly my mole grips are in danger of crushing the outer pipe before it gives way so don't want to put too much more pressure on it if it's not going to work!
If it has thread lock on it, heat often breaks it down.
Thanks @roverp480 - I did try a bit of MAPP gas on it but didn't seem to make any difference - might have been just a bit timid with it I suppose! Wasn't sure how much the manifold would appreciate it but maybe I'll give it another go. Can't see any other way to do it save maybe finding out what the thread is and drilling and tapping it out somehow...


Active Member
Tapping on the end has worked for me with broken off bolts, along with penetrating stuff(acetone+ATF, 50--50). Also lately have had a win with a gas freeze spray that seriously chills the item and can help break the grip of the corrosion. What is the function of that tube? I think I have separate pipes under the manifold.
Thanks @jp928 - it's this one (Rimmer Bros page) which takes the water from the pump to the heater, through the inlet manifold (not the one under it). Spoke to Mark Gray this evening who was v helpful but suspected it'd probably corroded solid to the manifold with age. I'm thinking I might try drilling it out. It doesn't take a huge amount of mechanical strain I suspect, can anyone think of an obvious substance to glue the replacement in if I drill out the thread? Wondering if JB Weld would do the job.


Well-Known Member
It is worth seeking out JB Kwick Weld, it goes off in around 10 mins, and does seem to set harder than the regular stuff.