Welding flywheels

In my earlier post, I mentioned that one of the flywheels for my 5HP Bulldog is cracked. Has anyone ever successfully repaired a flywheel by welding? Almost all posts I've read here dealing with cracked flywheels recommend finding another but that's probably not an option in this situation. What are everyone's thoughts?

Thanks...

Chris

Don't, when something happen in the future and the insurance see the welds, you have to pay the victim your self.$$$$

"Sixm" John

Cris, Welded/repaired flywheels are a definite No No. too much risk involved in the flywheel coming apart and slinging shrapnel all over the place. I definetly woundn't consider trying to repair it. Joe Morris

DONT WELD IT IS MY ADVICE. IF YOU HAD A LITTLE CHUNK OUT OF A HUB IT IS PROBABLY SAFE TO WELD THERE BUT IAM NOT EVEN SURE ID DO THAT. MANY FOUNDRIES COULD RE CAST THE FLYWHEEL USING THE OLD ONE AS A PATTERN. I KNOW THE CASTING COST AND MACHINING WOULD BE HIGH , BUT YOU WOULD BE ABLE TO SLEEP BETTER.

Chris I wouldnt. If its a static display OK but not one that you intend running. You will find one somewhere. BTW we gonna see you at Haddam? Kent? Dublin? See ya bud.John.

Chris, The only way I would trust repairing the spokes on a flywheel is to have a gentleman in Riverside, CA repair it. He brazes the cast iron and will guarantee the repair to be better than new. He utilizes a special technique which accomodates the shrinkage after cooling. His business is called "Cast Iron Welders" and he repairs cast iron machinery full time, brazing only. I have used his services and they are first rate. Probably a far distance from you though. Mike

Do NOT under any circumstances weld a flywheel. Be patient and find another, or have one cast. Al Wait

I agree welding is probably not a good idea. You know Paul Harvey on the radio says he doensn't even use his welder anymore. That JB Weld stuff makes welders nearly obsolete according to him. Maybe you could ask him how it would work on a broken flywheel. Kevin

Chris, paint it up and show it as a non runner until you find a replacement. No shame in that and the life you save might be mine.. Randy Hart Ohio

This is not a job for the backyard welder, but if performed by a competent professional who guarantees his work, I would have no problem with a repair job on any part. But thats just me. I realize, safety is the most important factor here, but stop and think about it for a minute. How many running engines out there have hidden cracks, covered by gime and paint that are running all the time? Chris would have the advantage that his part was repaired and could keep a special eye on it. Most of the show engines run slow with no loads on them so, again,,I'd have no problem with a first rate repair. Another option possible is to try and find a parts engine with the flywheel you need. It probably would cost more that just a flywheel, but could be cheaper than casting and machining a new one. It just boils down to what you're comfortable with. I respect every enginemans feelings on this controversial topic whether they agree with me or not. Thats what makes this board so great!! Good Luck Chris!!!

One consideration regarding welding or brazing is you would have a very hard time convince any potential buyer the result was safe. there is no standard or inspection process to prove the work. If you told a show official you were running an engine with a repaired flywheel, they would shut you down for sure. Thats is for sure.

My second concern, If you had the flywheel welded and later sold the engine, in my opinion you would be responsible. I think you would be responsible and "Should" be responsible. Who wants that liability?

Third comment, just and aside to iritate the engine painters. A nice paint job can hide a JB Weld time bomb. I do not like the idea of painting over a cracked flywheel, even for a static display. What if you pass away unexpectedly and someone else ends up with the engine.

I read a comment about engines running slow at shows. Well, sometimes engines speed up, governor failure. Where is your safety margin? People just dont take these kind of risks, not in steam boilers, not in home construction, times have changed. I propose, any repair you do should be as safe as the origional. Including overspeed situations. This is the classic reason for technology disasters. Multiple fails. it happesn. Space shuttle, sports arenas, etc... And its all so preventable and easy to criticism afterwards.

The alternative of casting a new one might not be to far out of the ball park of the carb build you already had done. Plus the cost of machining where you need to either catch a break or find a fellow collector to help. Cattail is an excellent foundry that specialized in exactly this kind of job. (location near Kinzers) I just had a couple pieces cast, this month. They were 26 lb iron cylinders at $65 each. Thats about $2 a pound. I think they can handle your needs. I assume you understand the old flywheel can be used as a pattern.

If you plan to go the new cast route, I'd start another thread asking about machinst help. Ive spoken to several engine guys who have done this.

my 4c

One comment was made that show engines are not generally run under load, hence a welded flywheel wouldn't be that big of a deal. This seems to ignore that the flywheel's stress loads are seldom related to the engines load unless a belt is run directly from the flywheel.

The flywheel's stresses are usually directly from centrifugal loads that are relative to the engines r.p.m. and exist in mostly the same magnitude regardless of whether the engine is loaded or not. Of course, as the r.p.m. goes up, so do the stresses- load or no load.

We were describing a process to a customer: Burning 2 1/2 GPM of liquid propane, to directly heat steel coil containing crude oil at 2K PSI. "No problem, real quiet process, safe as can be, do it all the time"

Customers' response: 'Dynamite is real quiet too, 'til it goes off'

JMcD

[Roy Van Oene]

I have welded cast iron with an ordinary 7018 successfully by heating the whole part red and doing the weld while red hot. By doing this I think anything would work. If I were to weld a flywheel I would cut a ring appx 3/8 off the flywheel and replace this with a ring of steel with a .0015/ inch shrink fit. This would be done for me only, and I would not do it for anyone else because of liability reasons-and I would not recomend doing it for the same reasons.

[Ray Cardoza]

Not really related to you're question but check out these disasters. Might make you think TWICE about welding a flywheel and running the engine like that

http://royalcrossfarm.com/Failure.html