How to remove siezed hot water take off plug.

[dpb]

I am trying to add a domestic hot water system to my AD41 engine and have stalled at the start as I cannot budge the plugs that I need to remove from the thermostat housing in order to fit the valves and fittings. I have used enough force to break my sump plug tool and am reluctant to apply more force for fear of breaking the thermostat housing…..especially given the price of a replacement!!!!
Any ideas or do I just keep pushing till it gives?

 

[vas]

I am trying to add a domestic hot water system to my AD41 engine and have stalled at the start as I cannot budge the plugs that I need to remove from the thermostat housing in order to fit the valves and fittings. I have used enough force to break my sump plug tool and am reluctant to apply more force for fear of breaking the thermostat housing…..especially given the price of a replacement!!!!
Any ideas or do I just keep pushing till it gives?

not familiar with the particular setup, but if it gets too tough, there's always heat that helps. In your case, you could run the engine up to temp and then turn it off and try
If it gives, wait for it to cool before removing (obviously)

Also light tapping with a hammer seems to help but I guess these threads have never been undone so I doubt how much it would help, no harm trying though.

V.

 

[aquatom]

If all else fails then remove the aluminium housing, get bolts (about M12) welded on to the steel plug then undo the plug immediately whilst still hot from welding.

Never fails!

 

[dpb]

not familiar with the particular setup, but if it gets too tough, there's always heat that helps. In your case, you could run the engine up to temp and then turn it off and try
If it gives, wait for it to cool before removing (obviously)

V.

Thanks for that but I have already drained the coolant so it doesn't come gushing out the unscrewed plug!

 

[dpb]

If all else fails then remove the aluminium housing, get bolts (about M12) welded on to the steel plug then undo the plug immediately whilst still hot from welding.

Never fails!

Oh great....I was worried enough when I thought it was a steel housing......didn't realize it was aluminium!!!
Good idea though, but its a bit of a work up to remove the whole housing I think. Will look into it further.
Thanks!

 

[Assassin]

Two options, pack ice cubes around the housing to cool it, but make sure they don't contact the plug/s to be removed, then undo them quickly. Drill the plug out and retap the threads if you know the size.

 

[jimmy_the_builder]

Two options, pack ice cubes around the housing to cool it, but make sure they don't contact the plug/s to be removed, then undo them quickly. Drill the plug out and retap the threads if you know the size.

Isn't packing the housing with ice going to make it contract, and thus make the plug an even tighter fit?

If the housing needs to be made bigger, then could you heat it - blowtorch (carefully!)/ hot air paintstripper gun? Then praps spray the plug with pipefreeze, and immediately try and ease it. Any good?

Cheers
Jimmy

 

[Trundlebug]

I am trying to add a domestic hot water system to my AD41 engine and have stalled at the start as I cannot budge the plugs that I need to remove from the thermostat housing in order to fit the valves and fittings. I have used enough force to break my sump plug tool and am reluctant to apply more force for fear of breaking the thermostat housing…..especially given the price of a replacement!!!!
Any ideas or do I just keep pushing till it gives?

Shock force is more effective than just steady force, although there are risks.

That is to say, use a sizeable hammer such as a lump hammer on the spanner / tool to overcome the initial sticking and get it moving, but use the right amount of force on the hammer and stop and inspect regularly in case you're doing any damage. (building up gardually helps with this, also helps get your aim perfected). Also watch out for what else you would damage if you mis-hit or if it gave in suddenly.

The idea given above sounds favourite if this method isn't practical, i.e. remove a bigger lump and do it on a workbench where you can really get at it.

 

[Assassin]

No, corrosion is oxide which expands and the ice contracts the housing and crushes the corrosion, it does not always work but when it does (most of the time) it makes life much easier.

 

[dpb]

Well, spent a little time on this today, went for the shock tactics to start, with lots of penetrating oil applied from both ends, but realised the 'socket' was starting to burr so have started drilling it out instead. Got up to a 8mm hole right through so am kind of committed now but the drill battery went flat so I could not enlarge any further. I think this will work but I was hoping to use the plug to determine the thread and won't be able to do this now. I am sure I saw it stated in another thread.
Thanks for the advice, I think heat would have been good but didn't have the right gear to hand, plus I was a bit weary about applying the heat with the housing still on the engine.
Will see how far I get next week end!

 

[scej]

have you bought Le ambiance

 

[noelex]

It might be too late, but I read on another forum a 50/50 mix of ATF and acetone was the best oil for loosening rusted parts.(keep it away from plastic)

 

[Cheekybrat]

Well, spent a little time on this today, went for the shock tactics to start, with lots of penetrating oil applied from both ends, but realised the 'socket' was starting to burr so have started drilling it out instead. Got up to a 8mm hole right through so am kind of committed now but the drill battery went flat so I could not enlarge any further. I think this will work but I was hoping to use the plug to determine the thread and won't be able to do this now. I am sure I saw it stated in another thread.
Thanks for the advice, I think heat would have been good but didn't have the right gear to hand, plus I was a bit weary about applying the heat with the housing still on the engine.
Will see how far I get next week end!

Try a stud extractor on it now you have the hole (as long as the hole is smaller than the thread size needed) but remember you only get what you pay for so don't use a cheap extractor and break it off in the hole
Nick Heath