Lister Engine Forum
How to / DIY => Engines => Topic started by: bullgoose on April 26, 2017, 04:27:19 PM
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Can I ask the members if the Lister D can be re bored with the cylinder head studs still in the block as there is no way mine are coming out without snapping off.
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I can't help you with the question about boring.. but re the cylinder head studs - have you tried Plus Gas? (I'm assuming you're in the UK) Absolutely amazing magical stuff... I took a 1977 Jaguar apart, one which had been sat outside in the rain not moving for 20 years, and I only sheared one bolt - everything else came free with a squirt of plusgas...
The other option, if even the plusgas won't shift it, is heat. Lots of heat ideally, you might need oxyacetylene (or at least oxygen+propane or polypropylene), get the area around the stud as hot as you dare, and try unscrewing it. I guess the only thing to be really wary of with heat is cracking the barrel due to uneven temperatures.
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Also try a 50/50 mixture of Acetone/ATF. Read this on some forum years ago, but only got around to trying it a few months ago. Blows any store bought penetrating fluid clean out of the water. Cheap to make too.
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Also try a 50/50 mixture of Acetone/ATF.
I keep meaning to try that one too. Haven't got any Acetone OR ATF though...
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Yes it can be bored with the studs in place. The standard automotive type boring bar cannot be used but I could bore it on my horizontal boring mill or also bring it to size with a ridged hone depending on how much material is being removed. We can also remove the stuck studs while set up on the mill and make new ones. If stuck hard you can soak them until hades is frozen over with whatever snake oIL you wish,,,, and they will still be stuck in the block
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snake oil
You say that... but genuinely, I have found Plus Gas to be indistinguishable from witchcraft. It Just Works. I have absolutely no connection with whoever makes Plus Gas (I don't even know who makes it...), I speak purely from experience of dismantling a 1970s British Sports Car - which, as any American will tell you, are made of rust held together by the stuckest bolts you've ever come across in your whole life. The metal around the bolts would rather fail than the bolts themselves come undone!
BTW, if you want to remove a stuck Aluminium (or even an Aluminum) bolt... go easy on the heat! Very easy to melt in an oxy-acetylene flame!! You may ask me how I know this...
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Use what works, even if its only in your mind,, ;)
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Hi everyone. Thank you all for your replies and sorry about replying late, I`ve been in hospital this last week.
I have used both plus gas and the Acetone/ATF penetrating fluids without success, but have not tried heating the studs hotter than red heat with a small Butane /Propane torch.
One of the hopper side studs is very wasted at the base and would be very likely to snap torqueing the head down so really should be replaced, but the others are only down a little on size. Can I ask the forum if any dimensions of the stud positions are known so I can make a jig and what the approximate length of stud is in the head.
The cylinder face or fire deck is ok around the bore but is a bit pitted around the hopper. Has anyone used epoxy products to fill these in or is that not practical without having the block skimmed.
When I dismantled the engine (Complete Nightmare) I found the fit of the bearing inner race to crankshaft on the flywheel side horrendously tight. Does it really have to be this tight or can I polish the crank a little to ease things up for reassembly.
I have talked to a local engineering company in Durham and they said to bring it down and try it on their boring machine which I hope to do soon.
I am a complete newby to stationary engines even though I have had this engine 20 years and would like to do what I intended to do with this little Lister all those years ago before I pop my clogs.
Thanks
Mick
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At the end of the day the studs are just (HT?) steel rod threaded into the barrel. If they snap off, as long as there is sufficient metal around them, they can be drilled out, the hole re-threaded oversize, and a new stud made and locked in place. A good engine machine shop will advise you, There are proprietary items such as "helicoil" inserts which may suit, or an insert can be machined. Care would have to be taken over positioning, verticality etc etc, so it's not a job for your local garage. It may also be that, if the machinist can cut the stud off flush bith the barrel and drill it carefully & incrementally, once there is only a thin "wall" of stud left attached to the barrel that it will lose strength and can be taken out with a stud extractor. Again, a good machine shop will know - someone who works on truck/digger/tractor engine . . . Good luck
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One of the hopper side studs is very wasted at the base and would be very likely to snap torqueing the head down so really should be replaced, but the others are only down a little on size. Can I ask the forum if any dimensions of the stud positions are known so I can make a jig and what the approximate length of stud is in the head.
The cylinder face or fire deck is ok around the bore but is a bit pitted around the hopper. Has anyone used epoxy products to fill these in or is that not practical without having the block skimmed.
When I dismantled the engine (Complete Nightmare) I found the fit of the bearing inner race to crankshaft on the flywheel side horrendously tight. Does it really have to be this tight or can I polish the crank a little to ease things up for reassembly.
I have talked to a local engineering company in Durham and they said to bring it down and try it on their boring machine which I hope to do soon.
I am a complete newby to stationary engines even though I have had this engine 20 years and would like to do what I intended to do with this little Lister all those years ago before I pop my clogs.
Hi Mick,
Have a gander over at the Mad Modder's forum (http://madmodder.net), you'll find there's loads of engineers in your neck of the woods; someone there will be willing to drill out the old studs - probably retaining the original threads, if they're good - for pennies (compared to taking it to an official shop). Plus, if you've got any interest in machining, you'll love the place (and if you've never thought about machining before... you might end up hooked). Feel free to say I pointed you in their direction, if you like - can't guarantee it'll get you a better price though!
FWIW, if I a) wasn't in China, and b) was a bit closer to Durham (I'm in Liverpool usually), and c) my workshop wasn't semi packed away right now, I'd offer to do it myself for you.
Cheers,
Ade.
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Thank you all for the replies, I have now joined the madmodder`s site and will see what can be done. One of the problems with rebuilding this little engine is keeping costs down to a sensible level. so finding people who can help with the stud using a milling machine would be fantastic. When the engine is finished I will almost certainly just give it away to a good cause like a younger or older member perhaps.
Thanks
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If this little engine was mine, I'd cut the studs off about 1/4" above the deck. Then grind the ends flat and center punch them. Then drill the studs with a left hand drill. The heat and reduction in size will frequently back out the threads. Then if that is not successful try an easy-out. And then if that's not successful, then drill to the correct size and retap the holes. The grinding flat and a center punch in the center of the stud is the key to this working.
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, then drill to the correct size and retap the holes. The grinding flat and a center punch in the center of the stud is the key to this working.
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I'd add a caveat to consider - just based on experience - that drilling and re-tapping original size is potentially fraught . . . .
First you have to dot that centrepunch EXACTLY right
Then there's no guarantee that each thread wont be cut half-and-half between original metal and old stud - with resultant loss of strength
just my $0,02. Cheers
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I don`t trust my self to get the centre punch mark in the right place on this occasion because the stud is so wasted at the base. Normally I would cut the stud leaving about 1/2 inch proud and ream a close fitting inch long length of bar to fit over the stud and then spot punch from the top. The problem with drilling down through a wasted stud is that the lips of the drill might break through the wall of the stud knocking the whole thing off centre, so on this occasion I will leave it to the professional's with a good milling machine and using a slot mill perhaps to create a flat in the middle of the stud below the fire deck as a starting point.
Can I ask if anyone has had ago at making a new carb spindle as I buggered mine trying to remove the butterfly valve screws.
Thanks
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, then drill to the correct size and retap the holes. The grinding flat and a center punch in the center of the stud is the key to this working.
I'd add a caveat to consider - just based on experience - that drilling and re-tapping original size is potentially fraught . . . .
First you have to dot that centrepunch EXACTLY right
Then there's no guarantee that each thread wont be cut half-and-half between original metal and old stud - with resultant loss of strength
just my $0,02. Cheers
The real trick is to use left-handed drills... and go in significantly undersized & creep up to the final size if you can. What you're looking for is one of the drills to "unstick" the threads, as soon as it spins the remnants of the stud, you should be able to withdraw it. And if not, well, you've drill the hole with backwards drill bits, so be it :D
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About 3/4 of the time, just the left handed drills will do the trick for me. Snap On makes a really nice set of lh drills and extractors. And if it doesn't tap to the old thread (unlikely, but possible) just helicoil it. If the studs are that bad, use the cylinder for a guide and transfer punch the centers of the studs. Do the drilling in a drill press if you have access to one.
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I Don`t have a pillar drill big enough I`m afraid and as the block has to go in to an engineering shop I will just leave it to them. All I have to do is buy an plus 20 thou piston just to make sure the re bore takes as some of the pits are deep ish. I think I will polish the crank at 20 degree intervals around the journal while trying the fit of the new main bearing until it`s a reasonably tight fit instead of the way the old one was.
During this week I have primed and painted everything except the block casting and have cleaned all the nuts/ bolts and studs for inspection. They seem ok and I will use as many original fittings as I can except washers which I will replace.
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I wonder if anyone can help with the amount of clearance needed when re boring a Lister D. The local engineering shop where I am having the re bore carried out just called and asked me what size I wanted the bore taken out to for the new plus 20 thou piston as he had no experience of cast iron pistons.
He said the piston was 3.018 at the skirt and smaller at the top but had no idea what the clearance per inch of piston dia should be. I thought it should be the size of the piston skirt plus 4 thou. Am I right about this?
thanks
Mick
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PM me your email, and I will send you some data on CI piston clearances.
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