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MGB Ring Gear Roulette

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DrEntropy

DrEntropy

Great Pumpkin
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The MG has apparently worn the ring gear to a dead spot. If I don't catch the start-up on the first spin, it becomes a contest to light it off. I've a "spare" flywheel with a good gear but no place to do the task of pulling the engine/trans at the moment. Garage is full of "stuff". No longer have a shop to use. I'm takin' this as a "sign" I should be using this COVID confinement as the ideal time to clear the decades worth of stuff not related to cars outta here.
 
Been there, done that doc. My ring gear moved about an inch from the shoulder of the flywheel. I was left with no choice but to pull the trans and flywheel and install a new ring gear. What a PITA for a $30 ring gear. With that said, I have not had any problems since installing the new one about 3.5 years ago. Get it done!

Ring gear moved away from shoulder
IMG_2087.jpg


New ring gear installed
IMG_2091.jpg
 
I think your neighbor owes you some "wrenching time"
 
Clean that garage out, Doc. Feels good to do, and you earn back space without having to spend any money. Were it possible, I'd come down and give you a hand. I'm well practiced at ruthless cleaning. My wife is much the same, it's a wonder our house isn't empty. :D
 
This'll take a "POD" rental, as my intent is to paint and rearrange the whole thing. There's plenty to purge, but there's much that I need to keep as well. Big stuff like three Snap-On roll cabs, band saw, drill press. Lots of that kind of stuff. MGB, Alfa and Lotus "spare" engines, heads... I get tired just contemplating it! :highly_amused:
 
Even with my big shop space, I'm trying very hard to be careful about what comes in. What comes in always tends to *stay* and even this big space can run out if I'm not careful.
 
You might want to consider using a pre-engaged starter out of a post 1968 MGB. I know that they can be fitted to the 5 main rear engine plate for 1965-1968 18GB cars but haven't personally checked to see if they match the 3 main rear plate but believe that they will. Just a happy coincidence that the spacing is correct. They slide inti the ring gear before twisting so no more crushed teeth.

Another cheap way around it is to remove the flywheel, turn one crank stud over and refit. The engines stop in only two positions so tat would present a 'fresh' set of teeth for the starter to use.

Here is a late starter fitted to my MGB Twin Cam race engine.

starter.jpg
 
Thanks for the info, Bill! This is a five-main 'transplant' so that could forestall the need to pull it out. Surprised I'd never tried that, considering all the MGB's we've had through the shop.

Looking at that photo, I'm curious! I see part of the intake, looks like it's meant to mount a pair of DCOE Webers? And what does the distributor drive from? One of the cams, I surmise. Would like to see more!
 
DrEntropy said:
Thanks for the info, Bill! This is a five-main 'transplant' so that could forestall the need to pull it out. Surprised I'd never tried that, considering all the MGB's we've had through the shop.

Looking at that photo, I'm curious! I see part of the intake, looks like it's meant to mount a pair of DCOE Webers? And what does the distributor drive from? One of the cams, I surmise. Would like to see more!
Click to expand...

That is the side of my 1950 cc 5 main Twin Cam race engine (I created it back around 1980). Last pic is when I was developing it and put it in my TVR Grantura Mk 3 race car as it was easier to get at things.

mgatc.jpg MGA_engine_compt.jpg tvrtc.jpg
 
That's durn'd impressive! Were you able to source the head or did you have to fabricate the inlet runners? Extensive work done to be sure. Did you have to cast the front chain cover? I don't recognize it.

I've a spare flywheel with a good gear and a new ring gear to replace the bad one on hand. Just need a cleared out garage!
 
Bill said:
The head and front timing assembly comes right off a Twin Cam engine. The trick was mating it all together.
Click to expand...


I can well imagine. Only ever laid hands on one MGA T/C, and that only for service; oil change and brakes. Been so many years ago I'll not recall details.

Very interested. Downloaded the .pdf, will peruse it.

Thanks!
 
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