Engine mount bolt removal

[Andie]

Hello

I've looked at all the postings online I can find regarding engine bolt removal, but would like to check that I'm not missing anything obvious. Apologies if this a bit of a newbie query.



I've soaked the bolt in plus gas for a month or so whilst doing other things - I've tried the nut and M16 washers trick - with a 6 point socket and an 18" breaker arm. There was a slightly scary/satisfying crack today but that was the threads being popped out of the nut. I've pulled the threads out of four nuts now so it's not moving. bought some A2 M16s but stupidly didn't check the internal thread - however I don't think that's gonna work regardless, although I'm ordering some 1.5 mm threaded nuts just in case.

I've not been banging it too hard with a hammer as I do not want to break anything. i understand the bolt is never greased as its meant to stick and the cones are doing their job by binding with the bolt. happy to delay powder coating til next month as long as I'm progressing in a hypocratic manner...

Is the forward motion now to hacksaw off at the mount face and drill the bolt out? - I assume its rust and cold welding on the mount bushes and cones. Is there anything I may have missed?

thanks for any suggestions!

[Warkton Tornado No.1]

The standard pitch is 'fine' 1.5 mm for engine bolts. Check that against an M16 standard (course) 2 mm pitch.

If I were you I would think about trying this:

Beg, borrow, steal an impact driver (18volt battery type would do, especially Milwaukee) & any impact sockets that come with it.

If there is a 24 mm, or something near, either obtain some hexagonal (good) steel or 'phone around a few sub-contract engineering shops/mates that work in toolrooms etc ,so that you have a long piece of the size needed (25 mm/an inch long minimum)

Have it bored & tapped to M16 x 1.5.

Fit it by screwing on the bolt by hand tools with a good thick washer underneath & some copaslip as lubricant.

Fit the impact socket to the driver & Warp Factor Five.

It should shift it & with the maximum thread engagement not damage anything further. You could keep swapping sides until the bolt really frees up.

I hope this might work.

[TurboTrev]

Take a look at this thread, it may help? http://scooterotica.org/forum/viewtopic.php?f=6&t=34843

[Captain Pugwash]

Right or wrong this is what I do.

Fit two nuts one on each end of the engine bolt just so that it sits on the end of the thread to protect the bolt, then take a lump hammer and give the nuts on the end of the engine bolt a swift whack on one side, then hit the other side.
Keep checking that the nuts haven't backed off revealing the thread of the bolt or the bolt will get damaged.
Repeat the whacking till the bolt fully releases then when it's loosened off tap it out from the mag side towards the drive side. If you take an engine bolt out towards the weaker mag side mount there's more chance of breaking the mount off, I've never broken one taking an engine bolt out, but I know others who have.

This sharp whack process should release the tapered grip that the cones apply to the engine bolt, both cones need to release completely before you try to extract the bolt, which is why I tap from one side then the other. Tapping from the mag side will release the drive side cone and from the drive side it will release the mag side cone.

As I said, "wrong or right" it's what I do to release a stuck engine bolt.

[petemaisey]

Always remember that the carb side engine lug is the weaker side. This is the the one that breaks off the rest of the case. Any bashing of the bolt should be towards the exhaust side.

Pete

[davla]

This worked for me after trying all of the normal suggestions......double nut one end of the bolt, heat the inner metal of the engine mounts (making sure you've drained the tank and left the residue to vaporise) and try and rotate the bolt with socket drive with a long handle (possibly a torque wrench). When you get a little bit of movement rotate it in the opposite direction and keep repeating. Give it and gentle tap with a rawhide/copper on the other side each time until it comes out. It might work, whatever you do don't go too crazy with the mallet!

[Andie]

Thank you

I'll try double nutting as davla suggests, and the freeze spray (worth a try) from trev.
New mounts is on the cards anyway.

I'm a bit weary of hitting it any more than I have Captain and Pete. I have applied some peen hammer action but it ain't moving...

the impact thing sounds interesting warkton - I can hire a driver for £18 a day, will try and source a local light engineering firm.

I guess we're hoping the bond between bolt and cones/bushes is less than that of cones/frame.

it took a week to get the well seized fork link bolts out, fortunately a colleague who apprenticed in building trains knocked them out after building a jig - they were incredibly seized and went off with a bang, but I'm well wary of my lugs and would resort to drilling rather that break them.

thanks again. That's next weekend sorted

[Captain Pugwash]

Best that You try the lesser evils first, mines more of a last resort.

But if you do try my method then your not trying to knock the bolt through, so you don't have to hit with great force as your only trying to shock the cones free of the frame and that then loosens the grip of the cones on the bolt and if successful then the bolt then moves freely.

An impact wrench will work as I sometimes do that prior to resorting to whacking the bolt.

Good luck

[Andie]

Thank you Captain, i will try gentle hammer persuasion as well as freezing and will try the impact driver too. All beat drilling it out (removing my leggies took a few days).

It's funny, the very basics (removing the engine - that has 1/2 page in every manual) has taken more time than anything else so far. thank you and the forum for helping me out!

[mickey c]

Sorry to be a harbinger of doom & I hope some of the above work but after getting nowhere for ages I had to resort to drilling it out! Some have found soft engine bolts & this straightforward, I lost count of how many drill bits I went through and barely got anywhere! Plus I was just heating the bolt seizing it yet further!
In the end I found an engineering firm with a magnetic drill (don't ask me what it is) 30 mins, £20 later all sorted. I did this as last resort but wish I did it much earlier due to the faffing about I would've saved!

[dickie]

Sorry to be a harbinger of doom & I hope some of the above work but after getting nowhere for ages I had to resort to drilling it out! Some have found soft engine bolts & this straightforward, I lost count of how many drill bits I went through and barely got anywhere! Plus I was just heating the bolt seizing it yet further!
In the end I found an engineering firm with a magnetic drill (don't ask me what it is) 30 mins, £20 later all sorted. I did this as last resort but wish I did it much earlier due to the faffing about I would've saved!

Carbide drills. Very expensive but they work. I had the same problem a few years ago so I bought a 13mm carbide drill that cut through the bolt like it was cheese. Only thing is that the drill was £15, so you may as well pay someone £20 to do it for you.

[Warkton Tornado No.1]

TBH, in the past, I have resorted to hammering a bolt out as has been suggested by others here.

I'm a bit older, & hopefully wiser, now though, than I was.

My suggestion, take it or leave it, is the closest you will get to a proper extraction tool.

It will not result in the likelihood of broken lugs as it is PULLING the bolt out but does need the shock of a proper impact driver.

PUSHING from the other side, especially without applying any torque whatsoever, is a risk as the bolt may take the mount & lug with it.

I've never broken a lug, but I've seen a few that have succumbed.

[Meds]

Have you tried a couple of kettles of boiling water instead of applying heat with a blowtorch or heat gun. It's gentle and gets everywhere

[joneo]

Had this problem on a mates Spanish 150 special that was just imported. Worried about the lugs by hitting the bolt too hard so started with a small drill bit and drilled along the top of the bolt through of the engine mounts. Not the rubber but the metal sleeve itself. Then went up a size and one more size again. Soaked it all in penetrating fluid, left it a little while then started tapping both sides of the bolt. Soon started moving. Knackers your mounts and possibly the bolt but they'll need replacing anyway. Did the trick for me.

[johnnyXS]

Right or wrong this is what I do.

Fit two nuts one on each end of the engine bolt just so that it sits on the end of the thread to protect the bolt, then take a lump hammer and give the nuts on the end of the engine bolt a swift whack on one side, then hit the other side.
.

I would think there is a very high risk of snapping off one or both of the aluminium crankcase brackets with that method unless you can adequately support both brackets whilst you whack the bolt. i've seen several crankcases for sale on ebay lately with welded brackets .

The easiest method by far is to weld a 1/2" drive socket on the end of the bolt or a T bar so that you can apply a lot of twisting force whilst simultaneously heating the aluminium brackets with a large Plumbers blow torch .
A used crancase in good condition is going to cost £150+ surely cheaper to take it to an Engineers workshop where they can press it out

[Warkton Tornado No.1]

Concerning some of the solutions suggested: Isn't a big part of this problem the fact that the engine is stuck in the frame?

How portable is it to manhandle (Oops! or womanhandle) on to any kind of mechanical device that will have the 'Ooomph' to force the bolt out? Heating will undoubtedly help, but as for a source of heat as in blowlamp, what about the frame & its component parts?

One thing is for sure. We're all waiting to see how it's eventually done, but that won't necessarily be by the best method, just what is available.

As an aside but due to this problem, besides having an M16 x 1.5 tap already (for cleaning up crankcase cover holes) I’m in the process of enquiring/obtaining an M16 fine ‘coupling’ nut to prove the principle, so if you’re prepared to wait, message me.

Kind Regards

Mark

[Eden]

Right or wrong this is what I do.

Fit two nuts one on each end of the engine bolt just so that it sits on the end of the thread to protect the bolt, then take a lump hammer and give the nuts on the end of the engine bolt a swift whack on one side, then hit the other side.
.

I would think there is a very high risk of snapping off one or both of the aluminium crankcase brackets with that method unless you can adequately support both brackets whilst you whack the bolt. i've seen several crankcases for sale on ebay lately with welded brackets .

The easiest method by far is to weld a 1/2" drive socket on the end of the bolt or a T bar so that you can apply a lot of twisting force whilst simultaneously heating the aluminium brackets with a large Plumbers blow torch .
A used crancase in good condition is going to cost £150+ surely cheaper to take it to an Engineers workshop where they can press it out

Most breaks there are due to people trying to remove the engine mounts by beating them to death not by knocking the engine bolt out!
As Mark said the engine bolt is stuck on the cones and probably not stuck on the mounts, and heating the aluminium brackets enough to free the bolt isn't going to help at all even if it is stuck on the mounts, to get the inner metal sleeve hot enough to expand off the bolt the rubber in the mounts would melt way before the sleeve expands!

[Rich Oswald]

Best of luck with this Andie and many thanks for making me the hub holder. Anything you need just give me a call,

Rich'

[Andie]

hello

Not much to report, i got some full size M16/1.5 nuts to play with (stud joiners aren't shelf available with 1.5 pitch) HSS didn't have an impact driver today (they no longer stock them), tapping and Plug gas and Shock lock sprays are ineffective and my Makita just blunted bits so I am planning to bite the bullet and get an engineering firm to drill it out. the mounts are turning btw, it is the cones.
Would rather get it done properly than break anything.

Any engineering firms in the Leeds area that could be reccomended would be appreciated!

*edit* the only impact driver I can hire is 250 Nm. 450 was suggested, is 250 worth a punt?

Cheers

Andrew

[Rich Oswald]

Hi Andie, if possible take it to Phil @ Torch Engineering, Mary Street, Castleford. He will get it out for you,

Rich'