Removing steel bolts from aluminium casting

[davel]

OK not really a boat maintenance question but hopefully the engineers (or Austin 12 owners) amongst you will be able to advise us.

 

We are trying to take off the water pump and the bolts are seized. We have already sheared off one and would also welcome advice on how to extract the rest of it. The engine has been standing since 1958, as far as I am aware all of that time inside.

 

The water pump housing and the piece it is bolted onto are both aluminium and we are not sure if the housing is threaded for the bolts, even though there are nuts on the back which came off fairly easily.

 

Thanks in advance.

 

Dave

[nb Innisfree]

I'm not an engineer but you could perhaps make a 'bund' out of plasticine or Bluetack, surround the housing with it and fill with diluted phosphoric acid or aluminium wheel cleaner, or Plus Gas. Leave to soak for a few days.

[NB Alnwick]

OK not really a boat maintenance question but hopefully the engineers (or Austin 12 owners) amongst you will be able to advise us.

 

We are trying to take off the water pump and the bolts are seized. We have already sheared off one and would also welcome advice on how to extract the rest of it. The engine has been standing since 1958, as far as I am aware all of that time inside.

 

The water pump housing and the piece it is bolted onto are both aluminium and we are not sure if the housing is threaded for the bolts, even though there are nuts on the back which came off fairly easily.

 

Thanks in advance.

 

Dave

 

I remember having a similar problem with the aluminium cylinder head of my old Triumph Mayflower.

I tried everything, including loads of releasing fluid but the combination of aluminium, steel and moisture had caused a corrosion that had the effect of firmly welded the bolts to the head. I even tried starting the engine with all the head nuts removed - it ran but the head (which was warped and had been leaking for years) did not budge. I eventually used a combination of heat and a sledge hammer (having removed and stripped the rest of the engine) with a piece of two inch diameter steel knocking the head up from below - the head eventually came off but it was destroyed in the process and most of the studs snapped!

 

Against this background, and if you want to save the aluminium components, I would advise carefully drilling the studs or bolts out to the depth and diameter of the aluminium that is holding them in place.

 

It should then be possible to fit new bolts or studs when re-assembling.

Edited November 24, 2009 by NB Alnwick

[davel]

I'm not an engineer but you could perhaps make a 'bund' out of plasticine or Bluetack, surround the housing with it and fill with diluted phosphoric acid or aluminium wheel cleaner, or Plus Gas. Leave to soak for a few days.

 

 

Thanks for that but would Phosphoric acid (even diluted) eat into the aluminium or does it just eat the corrosion and where would one get some.

 

Cheers

 

Dave

 

Edited for bad where-ing

Edited November 24, 2009 by davel

[Sir Nibble]

Heat. It softens the corrosion deposits and the differential expansion of the dissimilar materials cracks the chemical bond. Keep it hot and work the bolts back and forth until they undo. If all else fails a helicoil is not just a repair, it is an improvement.

[hughc]

I had the same problem with a Triumph Mayflower. The agents said they used a tool looking rather like a deep hole saw with very thin walls and fairly coarse teeth around the bottom edge. They then replaced the studs with oversized ones. They would not of course either lend or hire out this tool and in the end the head never did come off. Regards, HughC.

[Naughty Cal]

Heat followed by releasing agent/other lubricant leave to stand a while then have another crack at it.

[RLWP]

OK not really a boat maintenance question but hopefully the engineers (or Austin 12 owners) amongst you will be able to advise us.

 

We are trying to take off the water pump and the bolts are seized. We have already sheared off one and would also welcome advice on how to extract the rest of it. The engine has been standing since 1958, as far as I am aware all of that time inside.

 

The water pump housing and the piece it is bolted onto are both aluminium and we are not sure if the housing is threaded for the bolts, even though there are nuts on the back which came off fairly easily.

 

Thanks in advance.

 

Dave

 

What is the availability of water pumps for Austin 12's ?

 

Richard

[nb Innisfree]

Thanks for that but would Phosphoric acid (even diluted) eat into the aluminium or does it just eat the corrosion and where would one get some.

 

Cheers

 

Dave

 

Edited for bad where-ing

Yes it would eat into ally if left for too long but I would think it would need to be in the order of weeks. If you are concerned use Plusgas

 

Aluinium cleaner should be available from a good motor factors I think.

Edited November 24, 2009 by nb Innisfree

[RLWP]

Is this the engine you have?

 

 

Is the pump that thing on top with the fan?

 

Richard

[alan_fincher]

Is this the engine you have?

If it is, that's really spooky, Richard.....

 

You just happened to have a picture of their engine!

[Sir Nibble]

I don't think that one has a water pump, looks like a thermo syphon system to me. The "thing on top with the fan" is the dynamo.

[RLWP]

I don't think that one has a water pump, looks like a thermo syphon system to me. The "thing on top with the fan" is the dynamo.

 

I'm a bit surprised an Austin 12 has a water pump at all...

 

six cylinder version:

 

 

 

Richard

 

Like that dynamo. Heath Robinson would be proud!

Edited November 24, 2009 by RLWP

[NB Alnwick]

I had the same problem with a Triumph Mayflower. The agents said they used a tool looking rather like a deep hole saw with very thin walls and fairly coarse teeth around the bottom edge. They then replaced the studs with oversized ones. They would not of course either lend or hire out this tool and in the end the head never did come off. Regards, HughC.

 

Yes - I still have details of this tool as an addendum to the Triumph Mayflower Workshop Manual!

Funny how we hang on to things, Mayflowers have not survived well but I bet there are still plenty of Workshop Manuals about - it was a very comprehensive document in loose leaf format so that it could accept the frequent factory updates.

 

In my opinion, drilling out the studs on the workbench is always the safest option option - especially if the prime concern is to save the aluminium castings.

 

I don't think that one has a water pump, looks like a thermo syphon system to me. The "thing on top with the fan" is the dynamo.

 

Water pumps were introduced as a solution to the early traffic jams - in those days a warm engine cooled by natural circulation would soon boil up if the car became stuck in slow moving traffic. As a result magazines like 'Autocar' carried advertisements for water pumps, made by independent accessory firms, that could be retro-fitted to improve cooling.

[eightpot]

If there is enough bolt remaining:

 

Find a nut that is slightly oversize for the bolt remains. Place nut over bolt. Weld nut to bolt. Job done, the heat from the welding should break the corrosion bond and you now have a nice new head to the bolt with which you can get a socket or ring spanner on.

[davel]

I eventually used a combination of heat and a sledge hammer

 

Against this background, and if you want to save the aluminium components, I would advise carefully drilling the studs or bolts out to the depth and diameter of the aluminium that is holding them in place.

 

It should then be possible to fit new bolts or studs when re-assembling.

 

Not quite at the sledge hammer stage yet, but you never know

 

Heat. It softens the corrosion deposits and the differential expansion of the dissimilar materials cracks the chemical bond. Keep it hot and work the bolts back and forth until they undo. If all else fails a helicoil is not just a repair, it is an improvement.

 

Heat followed by releasing agent/other lubricant leave to stand a while then have another crack at it.

 

Yes I think this is where we are going now, we were a bit worried about excessive heat it being aluminium, any advice?

 

What is the availability of water pumps for Austin 12's ?

 

Richard

 

So far a everything we have needed has been available.

 

 

Is this the engine you have?

 

 

Is the pump that thing on top with the fan?

 

Richard

 

 

I don't think that one has a water pump, looks like a thermo syphon system to me. The "thing on top with the fan" is the dynamo.

Different engine to one in your photo carb is on left hand as you are looking from the front and you can see the dynamo housing at bottom right of engine

 

 

 

Water pump is at top with seized bolts going down to nuts which we have loosened

sheared bolthead to bottom left

[RLWP]

 

Water pump is at top with seized bolts going down to nuts which we have loosened

 

Those studs with no nuts on them towards the bottom of the picture. Does that mean there is a flange that holds the pump to the crankcase? Will the pump come off like that. I ask because it is going to be easier to drill the bolts out with a drilling machine than a hand drill...

 

If I had designed that, the holes through both castings would be plain, with the bolts retained by the nuts on the back. There is only just enough metal in the rear flange for a thread. If I am wrong and the rear flange is threaded, and you knackered the thread (technical term), the nuts would still retain the bolts.

 

What year is this car?

 

Richard

 

Aha! New plan. Put a socket over the head of the bolt. Put a nut loosely on the thread. use a G-clamp with it's foot on the socket and head on the nut. Tighten up and see if the bolt moves.

 

Richard

Edited November 24, 2009 by RLWP

[davel]

If there is enough bolt remaining:

 

Find a nut that is slightly oversize for the bolt remains. Place nut over bolt. Weld nut to bolt. Job done, the heat from the welding should break the corrosion bond and you now have a nice new head to the bolt with which you can get a socket or ring spanner on.

 

'Fraid not, sheared off flush.

 

Those studs with no nuts on them towards the bottom of the picture. Does that mean there is a flange that holds the pump to the crankcase? Will the pump come off like that. I ask because it is going to be easier to drill the bolts out with a drilling machine than a hand drill...

 

 

 

What year is this car?

 

Richard

 

Aha! New plan. Put a socket over the head of the bolt. Put a nut loosely on the thread. use a G-clamp with it's foot on the socket and head on the nut. Tighten up and see if the bolt moves.

 

Richard

 

The studs at the bottom of the picture are in a slot in the piece they come out of which is an adjuster for the cam chain which also drives the water pump. There is brass castellated nut in between the two studs, which we need to undo with a 'C' spanner and that will release the water pump.

 

It's a 1931 Burnham

 

Dad is going to try this if he can get his blowtorch working!

[RLWP]

'Fraid not, sheared off flush.

 

 

 

The studs at the bottom of the picture are in a slot in the piece they come out of which is an adjuster for the cam chain which also drives the water pump. There is brass castellated nut in between the two studs, which we need to undo with a 'C' spanner and that will release the water pump.

 

It's a 1931 Burnham

 

Dad is going to try this if he can get his blowtorch working!

 

You have four more to get out yet. If they come out, and if there are no dowels, you may be able to wiggle the housing to free the sheared off one.

 

Isn't that castellated nut the one that holds the packing for the gland in the water pump? The one that stops water leaking out along the shaft.

 

Richard

 

Perhaps you can drive the sheared off one in with a punch, but support the flange as much as you can first. Perhaps a socket over the nut and metal shims behind to support it?

Edited November 24, 2009 by RLWP

[Big COL]

Yes - I still have details of this tool as an addendum to the Triumph Mayflower Workshop Manual!

Funny how we hang on to things, Mayflowers have not survived well but I bet there are still plenty of Workshop Manuals about - it was a very comprehensive document in loose leaf format so that it could accept the frequent factory updates.

 

There were two mayflowers in the classic car section of the Earls Barton steam fair this year. As a child they seemed quite big cars as did the zodiacs, by todays cars they are actually a lot smaller than memory serves, the same with the motor bikes.

[steelaway]

'Fraid not, sheared off flush.

 

 

 

 

 

Hi

 

I would attempt to remove the other bolts, with some heat applied.

I they do all shear of , when the housing is removed there should still be enough stud sticking out to use a stud remover tool.

Clicky

 

Alex

[davel]

You have four more to get out yet. If they come out, and if there are no dowels, you may be able to wiggle the housing to free the sheared off one.

 

 

 

Isn't that castellated nut the one that holds the packing for the gland in the water pump? The one that stops water leaking out along the shaft.

 

Richard

 

Perhaps you can drive the sheared off one in with a punch, but support the flange as much as you can first. Perhaps a socket over the nut and metal shims behind to support it?

 

There is brass castellated nut in between the two studs, which we need to undo with a 'C' spanner and that will release the water pump.

 

Yes you're right, I'm talking complete rowlocks here, it just holds the impeller shaft and packing in its housing.

 

A combination of heat and G cramps has got the pump housing off, though the bolts are still in the housing but at least they will be easier to work on now.

Hi

 

I would attempt to remove the other bolts, with some heat applied.

I they do all shear of , when the housing is removed there should still be enough stud sticking out to use a stud remover tool.

Clicky

 

Alex

 

That looks like a handy tool

 

Edited for bad grammar

Edited November 24, 2009 by davel

[RLWP]

Yes you're right, I'm talking complete rowlocks here, it just holds the impeller shaft and packing in its housing.

 

A combination of heat and G cramps has got the pump housing off, though the bolts are still in the housing but at least they will be easier to work on now.

 

 

That looks like a handy tool

 

Edited for bad grammar

 

Progress - well done! At least you can now use a vice on it, or support it while you show it a variety of hammers.

 

Richard

 

Please keep us informed, won't you.

[Byeckerslike]

Yes - I still have details of this tool as an addendum to the Triumph Mayflower Workshop Manual!

Funny how we hang on to things, Mayflowers have not survived well but I bet there are still plenty of Workshop Manuals about - it was a very comprehensive document in loose leaf format so that it could accept the frequent factory updates.

 

In my opinion, drilling out the studs on the workbench is always the safest option option - especially if the prime concern is to save the aluminium castings.

 

 

 

Water pumps were introduced as a solution to the early traffic jams - in those days a warm engine cooled by natural circulation would soon boil up if the car became stuck in slow moving traffic. As a result magazines like 'Autocar' carried advertisements for water pumps, made by independent accessory firms, that could be retro-fitted to improve cooling.

 

Have you tried Jim Bergerac?

 

he has a triumph Roadster

 

What you are suffering from is bi-metallic corrosion (which is one reason why automobiles went to negative earth in the late 60's.

 

Rob

Edited November 24, 2009 by Byeckerslike

[sultan]

This is a familiar situation and there is no easy remedy. The problem is that the corrosion products of aluminium occupy a much greater volume that the original metal . Moisture works its way by slow capllary action between the bolt and the casting. It oxidises the aluminium to produce a hard grey-white compound that expands as it forms, to complete fill the already tight space between the bolt and the casting. Depending on how long the corrosion continues, it can exert enormous force ,like water freezing in a pipe and like freezing water, can break the casting. Bear in mind when trying to free the bolts, that the casting will have been highly stressed by the formation of the oxides and is probably very fragile. It may also be partially recrystalised through ageing, so brute force is not the answer. The best remedy is heat combined with a gentle tapping. It would be hopeless but for the fact that thermal expansion of aluminium is much greater than steel so you must contrive to heat the aluminium as much as you can, short of melting, it to get the aluminium to relax its grip. If you can avoid directly heating the bolts, so much the better, then tap ond rock the bolts without letting it cool down. If it cools, the grip will be restablished. Using a freeing oil while doing this may help but beware that if the oil carbonised between the castng and the bolt due to the heat, it may contribute to the grip.

Best of luck