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MGB Flywheel saga continues....

YakkoWarner

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I heard back from Moss about the question of why my new flywheel only has one locating dowel hole whereas my old one (and engine) have 2.

According to Moss, the factory DID change to using only one locating dowel at some point, and therefore the flywheel is technically the correct part, and they indicated that the proper procedure for installation is to remove one of the locating dowels from the crank.

So my NEW question is, has anyone ever actually tried to remove one of those? Is it possible to do so without using heat (which could melt/destroy the rear main seal) or getting totally medieval on them with some sort of chisel/hammer (which could destroy the main/thrust bearings)? The man at Moss seems to indicate they could just be rotated/pulled on with an aggressive vice-grip, but that sounds almost too easy....I feel like there's got to be a complication somewhere because nothing involving installing this particular part has been that simple.
 
I have very limited experience with this (My Midget & My Vauxhall) but, in both cases the locating pin was removeable - just a press fit. It should just pull out.

Good luck and glad you found an answer
 
Only "victim" here is a short block with the two dowel crank. It has propped up the garage beer cooler for years. Nice and rusty, too. Just for S&G's may try an extraction of one of the dowels t'morrow with minimum shock or temp extremes.

Stay tuned!
 
Only "victim" here is a short block with the two dowel crank. It has propped up the garage beer cooler for years. Nice and rusty, too. Just for S&G's may try an extraction of one of the dowels t'morrow with minimum shock or temp extremes.

Stay tuned!

Please do let me know - right now it seems like the only thing preventing the entire drivetrain installation is one of those little dowels so I am very interested in how it goes.
 
This is a friction fit, and maybe you can fit some locking pliers and a slide hammer.
A bit reluctant to use a slide hammer, due to possible thrust bearing damage. Trying to do this with as little brute force as necessary.

I did get a good grip on one with ViseGrips and tried to pry against the crankshaft shoulder, with no joy.

Have applied weasel pee and will give that a couple more treatments, then use a 7/16" "stud remover" to try a bit of rotation before another go with V-Grips and prybar. Maybe try somehow arranging a "steering wheel" type puller with the pliers...

Please do let me know - right now it seems like the only thing preventing the entire drivetrain installation is one of those little dowels so I am very interested in how it goes.

Been recovering from a fairly significant surgery, so next go may be in a day or so. I'll not give up.
 
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Sorry, but if using this damages the thrust washers, then he has bigger problems.
 
A bit reluctant to use a slide hammer, due to possible thrust bearing damage. Trying to do this with as little brute force as necessary.

I did get a good grip on one with ViseGrips and tried to pry against the crankshaft shoulder, with no joy.

Have applied weasel pee and will give that a couple more treatments, then use a 7/16" "stud remover" to try a bit of rotation before another go with V-Grips and prybar. Maybe try somehow arranging a "steering wheel" type puller with the pliers...



Been recovering from a fairly significant surgery, so next go may be in a day or so. I'll not give up.

I tried the same trick on my end (get on it really agressive with the vicegrip and pry on the shoulder)...all I did was put a good size gouge in the pin.

I'm kind of to the point of either grinding it down or just giving up on this motor. Nothing this simple should be this impossible to do...my mechanic friend is suggesting breaking down the whole motor which if it comes to that may just be the end of it.
 
View attachment 93796View attachment 93796Sorry, but if using this damages the thrust washers, then he has bigger problems.
Only real problem is getting a way to grip that dowel so as to actually USE the slide hammer. Maybe thread it? No die I have will fit tho.

Someone needs to come up with a "tool" like the "Chinese Handcuffs" but for metal. My 7/16" sprag doesn't fit between the dowel and shoulder on the crank. No joy with that.
About to try with the ViseGrips and a two-point hold with the slide hammer.
 
No way to grip the dowel. I've Proto's "Six Ton Puller Set" with allsorts of stuff for separating things from each other. But without the ability to grip that dowel securely, not much will do except welding a piece of something to grab onto. Not much of a solution!

IF the crank is drilled all the way through, driving the dowel out from the other side would work. BUT(!) full bottom-end disassembly would be needed.

A Dremel and a cut-off wheel would surgically level it. That'd be my solution under the circumstance.
 
No way to grip the dowel. I've Proto's "Six Ton Puller Set" with allsorts of stuff for separating things from each other. But without the ability to grip that dowel securely, not much will do except welding a piece of something to grab onto. Not much of a solution!

IF the crank is drilled all the way through, driving the dowel out from the other side would work. BUT(!) full bottom-end disassembly would be needed.

A Dremel and a cut-off wheel would surgically level it. That'd be my solution under the circumstance.

That is kind of where I am leaning toward - use a more agressive wheel to get it close and then be precise with a dremel to take it the rest of the way to flush, hopefully without harming the crank shoulder.

The folks at Moss were indicating it should just pop out, but since its been in there for pretty much 50 years that seems to not be the case...my choices are grind or engine teardown. If that goes poorly then its engine teardown, so to me there seems little risk to grind first since the penalty if it goes wrong is merely the other option anyway.
 
Are the pins through hardened, case hardened or "soft"? I wonder if one could drill/thread a hole along the center line of the pin. Then make a puller with a socket and bolt. If in my garage, I might try clamping an end mill holder to the pin to have something solid to pry against.

Any machine shops in the area that might be willing to part with a trade secret?
 
Are the pins through hardened, case hardened or "soft"? I wonder if one could drill/thread a hole along the center line of the pin. Then make a puller with a socket and bolt. If in my garage, I might try clamping an end mill holder to the pin to have something solid to pry against.

Any machine shops in the area that might be willing to part with a trade secret?

Since I put a good size gouge in one of the dowels with my vice-grip attempt I am going to "assume" they are not hardened. I thought about the drilling and threading. My hands aren't that steady. If there was room, threading the outside would have been an option also but there is the centering flange for the flywheel about 1/4 inch away so no room for anything like an end-mill holder to get on it. If they ARE hardened, grinding is going to be a you-know-what also....

If I could find a decent machine shop to ask, I could probably just get my old flywheel resurfaced which is how I ended up falling down this rabbit hole to begin with - I couldn't find anyone who does that kind of work anymore.

Its going to be a couple weeks before I can get back up to the shop at this point because I have music shows this weekend, if anyone comes up with any strokes of brllliance that don't involve a full motor tear-down I am all eyes and ears....
 
The pins aren't hardened. Cut it off and level it. 👍
 
With Doc on the cut off. Another method would be to drill press a hole the diameter of the dowel in a plate, very fairly the edge. Plate should be 1/2 inch thicker than the dowel is high. Put the plate hole over the dowel and use it to establish the center with a drill bit the same diameter as the hole/dowel. Then go to a slightly smaller bit so the edges of the dowel keep the bit centered. Keep drilling until the hole is deeper than the surface of the crank flange. Getting rid of the remaining "shell" of the dowel would be easy with a Dremel. This method would eliminate excess grinding on the crank flange. The guide plate could be aluminum for easier machining.
Bob
 
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I used a pair of Vise Grips with my HF slide hammer. The threaded portion of the slide hammer is the same as the Vise Grip adjusting screw…worked a treat.
Rut
 
With Doc on the cut off. Another method would be to drill press a hole the diameter of the dowel in a plate, very near the edge. Plate should be 1/2 inch thicker than the dowel is high. Put the plate hole over the dowel and use it to establish the center with a drill bit the same diameter as the hole/dowel. Keep drilling until protruding part of the dowel is gone. This method would eliminate any grinding on the crank flange. The plate could be aluminum for easier machining.
Bob

Now that could possibly work and I already have a "plate" - otherwise known as the rusty flywheel - put some washers behind it to space it out, bolt it on and there would be the perfectly aligned guide.

I kind of like a hybrid of this idea - cut the pin that needs to be gone down close but not quite flush (to avoid scarring the crank shoulder), then use the old flywheel as a guide to drill the pin down slightly below flush without touching the crank. Does that sound like something plausible that could be done with without access to an actual machine shop?
 
I used a pair of Vise Grips with my HF slide hammer. The threaded portion of the slide hammer is the same as the Vise Grip adjusting screw…worked a treat.
Rut

How hard did you have to whallop on the slide hammer to get it to move? I really like this idea more than drilling/grinding (mainly because sounds less dangerous) unless it took serious effort and then I worry about stressing the internal thrust bearings. I may be making a field trip to HF next week....
 
Given the mass of the crank (40 some pounds) , I really don't see much transfer of hammer blow energy to the thrust bearings. I do see some possibility of mushrooming the shoulders of the crank hole the dowel is in, though. But if you deform the dowel much and fail in removal, finding center may become difficult.
Bob
 
The threaded portion of the slide hammer is the same as the Vise Grip adjusting screw…worked a treat.
(y)(y)(y)(y)

This seems like a "no-brainer"!!! Nothing I've got here for a slide hammer is small enuff diameter/pitch to work or I'd be on it just for edification's sake!
 
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