I purchased a Tecumseh HS40 model number 55232A off of Ebay for my 72 Roadster...should have looked closer before I bought it. It came with a lighting coil, but has the wrong flywheel P.N. 32517 (non-lighting). I bought a lighting flywheel P.N. 610769A. When I swapped the flywheels, the shround will fit, but the pull start is locks up like it is not meant to fit this engine (can't pull it at all). I am at an extreme loss for what to do. Does anyone know??? Any guidance would be more than appreciated.
72 Rupp Roadster Engine Help!!
- Thread starter Mrgrayfox
- Start date
- Tags lighting flywheel help
I'm pretty sure that that flywheel will not interchainge with that shroud, and if it did you would problaby loose cooling capabilities. Did you take off a steel flywheel with plastic fins?
does the shroud look like this:
or like this:
also what do the points look like?
I lighted one should look like this:
non lighted will look like this:
does the shroud look like this:
or like this:
also what do the points look like?
I lighted one should look like this:
non lighted will look like this:
that should all interchange (I don't know about the coil assy :shrug
, when I used that part # for your motor at partstree.com it pulled up a later shroud/flywheel assembly which would not interchange.
All I can think of is the flywheel is not getting seated deep enough on the crankshaft for some reason. Is that coil assy something that was already on the bike and was it running or at least turning over with the non lighted wheel on it?
That or the studs for the pull start are too long, but again that would have affected the other flywheel most likely.
, when I used that part # for your motor at partstree.com it pulled up a later shroud/flywheel assembly which would not interchange.All I can think of is the flywheel is not getting seated deep enough on the crankshaft for some reason. Is that coil assy something that was already on the bike and was it running or at least turning over with the non lighted wheel on it?
That or the studs for the pull start are too long, but again that would have affected the other flywheel most likely.
Yes, the coil was on there when I bought it, I had the whole thing running with that pull starter. The seating of the flywheel is a good point, I will look into that (the taper and hole size look the same too).
There are 2 other issues I came across.
1. The wire mesh piece didn't fit right with the lighted flywheel, so I had to cut the bottom off a bit to make it fit. Does this sound like anything you have done before? Makes me think something isn't right.
2. The guy who redid this engine put some welds on the backside of the shroud where the pull string mounts are. One of the welds does stick out further then the others, but it wasn't a problem with the old flywheel. I did notice that the fins on the lighted flywheel stick up about an 1/8 of an inch...maybe they are getting hung up on the weld???
This is my first restoration and it has been a struggle. I appreciate your help!
There are 2 other issues I came across.
1. The wire mesh piece didn't fit right with the lighted flywheel, so I had to cut the bottom off a bit to make it fit. Does this sound like anything you have done before? Makes me think something isn't right.
2. The guy who redid this engine put some welds on the backside of the shroud where the pull string mounts are. One of the welds does stick out further then the others, but it wasn't a problem with the old flywheel. I did notice that the fins on the lighted flywheel stick up about an 1/8 of an inch...maybe they are getting hung up on the weld???
This is my first restoration and it has been a struggle. I appreciate your help!
The shrouds are the same size wise there is a difference when it comes to the way pull starts bolt on. Yours looks like the right style, but you said there was a weld on one or something on the backside? I just looked at a stack of shrouds I have in the garage, the Rupp ones with studs are practically flush witheh shroud on the backside, just a flat thin "head". Ones that use a bolt to install have sort of a "nut-sert" on the inside which sticks out say 1/4-3/8". With that said I looked at 2 complete Rupp motors I have on the shelf which both turn over etc.. and it does not look like that would even be a factor. but I was also peering into the shroud through the hole with a flashlight, at 6am, only one cup of coffee:wink:
I gotta go to work, but can pull a shroud off a '71/72 lighted 4hp tonight if you dont get it figured out and we can compare them via pics etc.. I would pull that recoil right off the shroud, and also do some loose assembling and see how it fits. just slip the flywheel on (I would take the key out for this) and slip the bare shroud on and see how fitment is and just keep adding the parts till you find the culprit.
I gotta go to work, but can pull a shroud off a '71/72 lighted 4hp tonight if you dont get it figured out and we can compare them via pics etc.. I would pull that recoil right off the shroud, and also do some loose assembling and see how it fits. just slip the flywheel on (I would take the key out for this) and slip the bare shroud on and see how fitment is and just keep adding the parts till you find the culprit.
Blower housing clearance
I think I have the answer if anyone is interested. I spoke with the guy at Rupp Parts and he said all the blower housings are the same. The clearance on the ones with lighted flywheels, however is different. He said the used a very flat topped bolt head with a clearance of around 1/16th of an inch. He said that the clearance can be so tight, that when people tipped their bikes over the flywheel would rub on the bolt heads or take part of the flywheel fins out.
I will have to grind mine down (see the photos). Anyone out there have one in near perfect shape with the proper bolt heads they would be willing to part with??
As you can see, someone modified this cover.
I think I have the answer if anyone is interested. I spoke with the guy at Rupp Parts and he said all the blower housings are the same. The clearance on the ones with lighted flywheels, however is different. He said the used a very flat topped bolt head with a clearance of around 1/16th of an inch. He said that the clearance can be so tight, that when people tipped their bikes over the flywheel would rub on the bolt heads or take part of the flywheel fins out.
I will have to grind mine down (see the photos). Anyone out there have one in near perfect shape with the proper bolt heads they would be willing to part with??
As you can see, someone modified this cover.
Looks like a snow blower shroud with the extra holes and the wrong lighting coil for a Rupp. Someone modified it up to look like a Rupp. Curious to see what else they may have done to it.
After taking another look, the carb is not a Rupp and by the looks of it, neither is the throttle bracket. You may very well have a modified lighted snow blower engine on your bike.
After taking another look, the carb is not a Rupp and by the looks of it, neither is the throttle bracket. You may very well have a modified lighted snow blower engine on your bike.
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Just wanted to show you the inside to a 72 Rupp HS40 55388C 2066B shroud. Your model numbers should be the same and the serial number should start with 2. Also, look at the ID tag closely. The rivets in mine have three slots in them (refer to picture) and are barely sticking through the shroud. The bolts have flat heads on them.
Thats good info to know about the studs vs inserts, something I never thought much about/ Since I am working on some light motors, I best test fit things before I go redoing the shrouding!
With that said though, I bought this Rupp to finish recently, The shroud that was on it is tagged as a sears something or other and it is a shroud that has inserts instead of studs. And yes it turned over that way and had correct lighted parts underneath.
I think the fins on the flywheel may have been a little marred up though. I would attempt to smooth yours out and hopefully save the shroud. Bummer is you have to deal with 8 humps instead of 4, its worth a shot.
Thats a bummer your going through this, I take it none of this was disclosed at time of sale:no:
With that said though, I bought this Rupp to finish recently, The shroud that was on it is tagged as a sears something or other and it is a shroud that has inserts instead of studs. And yes it turned over that way and had correct lighted parts underneath.
I think the fins on the flywheel may have been a little marred up though. I would attempt to smooth yours out and hopefully save the shroud. Bummer is you have to deal with 8 humps instead of 4, its worth a shot.
Thats a bummer your going through this, I take it none of this was disclosed at time of sale:no:
I ground down the bolt heads and got it spinning. Had it running, but am having carb problems.....go figure! I check the lighting wires and I have current (a small victory), however I must have a bad ground somewhere because the lights don't come on...back to the drawing board. Thank you to those who have helped me so far!