Stud removal nightmare! Steel in alloy. Help!!

[Harlan_Kovacs]

Hello chaps!

Please help, I've reached the limits of my experience! I'm removing the timing cover on my chim and I have a sheared bolt, which has now become a stud. It's one of the ones that passes through the water jacket of the water pump. It's not moved a pip. I rounded the bold head, welded a larger bold head on and then applied heat and did the wiggle many times. Thought I was getting movement but sheared it.

This allowed me to remove the water pump and exposed 25mm of the bolt. I used a stud extractor and heat. Progressed slowly. Attempted to wiggle it back and forth but In the end, it sheared again and I don't think it moved at all.

I now have 3 mm visible before it disappears into the timing cover. It feels so heavily welded in. I can't remove the timing cover to expose the remaining bolt/stud.

So what next? The block is in the car, on ramps in my single garage.

It feel like the only option left is to drill it out? But it's long and it passes into the block..

Problem!!

Any tips at all would be hugely appreciated!!

Many thanks,

Mark

[Dougal9887]

Mark, you clearly need to get the timing cover off over that bolt. I would try bolting some heavy flatbar to the water pump bolt flanges to the left of the problem bolt. This would give you a couple of handles to get hold of. Then use a blow lamp to heat up the alloy casting, get it really hot, to try to break the seal, the alloy will expand much more than the bolt. You will then have your handles to get hold of and wiggle/pull and hopefully free it. If not you could weld a piece of rod to the centre of the flat bar and make up a slide hammer of sorts to try to shock it free once hot, but care would need to be taken as this would be an offset action. Hopefully some ideas to work with.
Dougal.

[Harlan_Kovacs]

Thanks Dougal,

I'd not thought of that. I'd applied heat but was struggling with leverage etc. I'll give it a hash today and let you know how I get on. Thanks again for your suggestion!

Mark

[citizen smith]

Harlan_Kovacs said:

Hello chaps!

Please help, I've reached the limits of my experience! I'm removing the timing cover on my chim and I have a sheared bolt, which has now become a stud. It's one of the ones that passes through the water jacket of the water pump. It's not moved a pip. I rounded the bold head, welded a larger bold head on and then applied heat and did the wiggle many times. Thought I was getting movement but sheared it.

This allowed me to remove the water pump and exposed 25mm of the bolt. I used a stud extractor and heat. Progressed slowly. Attempted to wiggle it back and forth but In the end, it sheared again and I don't think it moved at all.

I now have 3 mm visible before it disappears into the timing cover. It feels so heavily welded in. I can't remove the timing cover to expose the remaining bolt/stud.

So what next? The block is in the car, on ramps in my single garage.

It feel like the only option left is to drill it out? But it's long and it passes into the block..

Problem!!

Any tips at all would be hugely appreciated!!

Many thanks,

Mark

Another possible solution providing that you have welding gear, is to drill a hole in an appropriate piece of bar that matches the 3 mm broken bolt and weld the flat bar to it.

At least then you would have some real leverage.

[Classic Chim]

I think you have your answers here. Excellent advice.
The length of bolt coupled with sealant will make any real pressure difficult to muster. I’d heat the bolt at it’s far end onlt and try again. Drilling a plate as suggested will allow a proper weld to form around what you have left of the bolt to get a decent purchase. Good luck

[Dougal9887]

I doubt the thread is the problem. Corrosion will have set in along the entire length of the bolt and I suspect even if you did get a strong enough weld onto the end, the bolt would just shear again. I'm sure heating and expanding the alloy casting is the way to go.
Dougal.

[Harlan_Kovacs]

Ok chaps. Solved. I tried all non destructive methods first but became convinced that the problem was indeed dissimilar metal corrosion essentially welding the shaft of the bold into the timing cover. I drilled the core of it out, leaving 0.5mm all round. Then using heat and a length of flat bar bolted to the water pump threads, with a slide hammer attached to it, managed to pull the cover off the stud. It was incredibly badly corroded. I don't think it saw any kind of sealant when it was last put in.

Once removed the remaining bolt was very easily removed. The thread was not in any way seised.

Would not have managed this with out your help, so that you very much!

Mark

[Steve_D]

Your problems may not be over. Next you need to find a replacement imperial bolt the correct diameter and length. Not a common combination.

Steve

[Classic Chim]

Dougal9887 said:

I doubt the thread is the problem. Corrosion will have set in along the entire length of the bolt and I suspect even if you did get a strong enough weld onto the end, the bolt would just shear again. I'm sure heating and expanding the alloy casting is the way to go.
Dougal.

Correct as it goes through water jacket my bad

[citizen smith]

Steve_D said:

Your problems may not be over. Next you need to find a replacement imperial bolt the correct diameter and length. Not a common combination.

Steve

To find a suitable bolt, you would have to go into the Rimmer Bros website - sub section Rover V8,- Timing Cover and Fittings - item 11 = 5/16" UNC Bolt and measure the depth of the cover then add some thread length for one that may work.

[Harlan_Kovacs]

Honestly, you guys are the best.

You've just directed me to the exact bolt I require.

Thank you, thank you, thank you!