So on hs40 orange motor, with the 1 inch PTO shaft, I was wondering if you can use an H35 crankshaft in place of it? Are they the same? Because I have a number of h35 short blocks I could steal the crankshaft, as an easier way to get a three-quarter inch PTO on the HS40 motor . The three crankshaft I showed in the pictures a few posts Back are for an HS50. I’m pretty sure those will not work. Also since this is a point and condenser model motor, the fly wheel is slightly different the tapered is cut differently. The three hs50 cranks I have are for solid state ignition hs50 motors, which won’t work on point and condenser model motors
Restoring a Tecumseh - another way
- Thread starter cfh
- Start date
If your governor system is at factory setting and you straight wire it without any adjustments to compensate your putting ALOT of stress and friction on a dinky plastic gear and spool that is spinning inside. When you take your you builds to the next level and open them up look at the gear and you may get a better understanding of whats happening in there...seizing one up cause it melted or broke wont be pretty!!!
In reality there is no need to straight wire, but to simply adjust out the just enough that it does not get pushed back by the spool as it ramps up. You do want keep the arm in as close of contact with the spool assembly as you can still, if you pivot it over too far it may want fight throttle return due to being off balance.....HS50's I have found to be the worst for that actually-they have a vibration all their own. Plus if say the c clip that retains the spool on the shaft were to fail or the pressed in shaft were start moving it would keep the Governor assy in place internally still. So when the kids come over its simply a matter of loosening the usually 5/16" bolt on the governor arm and quick adjust ( little twist clockwise) to get the governor system functioning again :thumbsup:
I also noticed you are not obtaining the full travel you can get out of the throttle mechanism, maybe this thread will come in handy for you on that....https://www.oldminibikes.com/forum/...e.html?highlight=Advice+hooking+Tecumseh+Carb
I always just rivet those mech's on the backing plate, Its how the factory did it starting in 1971, and less hardware to worry about possibly vibrating loose
best of luck with your builds :thumbsup:
In reality there is no need to straight wire, but to simply adjust out the just enough that it does not get pushed back by the spool as it ramps up. You do want keep the arm in as close of contact with the spool assembly as you can still, if you pivot it over too far it may want fight throttle return due to being off balance.....HS50's I have found to be the worst for that actually-they have a vibration all their own. Plus if say the c clip that retains the spool on the shaft were to fail or the pressed in shaft were start moving it would keep the Governor assy in place internally still. So when the kids come over its simply a matter of loosening the usually 5/16" bolt on the governor arm and quick adjust ( little twist clockwise) to get the governor system functioning again :thumbsup:
I also noticed you are not obtaining the full travel you can get out of the throttle mechanism, maybe this thread will come in handy for you on that....https://www.oldminibikes.com/forum/...e.html?highlight=Advice+hooking+Tecumseh+Carb
I always just rivet those mech's on the backing plate, Its how the factory did it starting in 1971, and less hardware to worry about possibly vibrating loose
best of luck with your builds :thumbsup:
Yes, the H50 is the correct engine for the Gilson Trail bike, Ward 525 series and any of the Allis bikes with a rear tank. Tankless Gilson built bikes had a 4hp engine. I have to agree with [MENTION=5969]markus[/MENTION]. The spool and counterweights will disintegrate pretty quickly under stress and when those counterweights come off, all hell breaks loose inside that engine. I've popped a couple open when that has happened and I find chunks of metal everywhere and a chunk of metal in a cam tooth will lock it up (think rotating mass seizing in an instant).
Well i have to split the case on a good number of these to deal with the crankshaft. So i guess i'll start removing the governor gears internally. That's the safe bet i would assume right? get all that crap out of there, so there's nothing to seize or break apart.
On the throttle mech i don't have any problems with travel. but your point is in the back of my head so i'll keep that in mind. I prefer using 8-32 screws with locknuts, opposed to rivets. this way anybody can easily change the throttle assembly. These things get hacked on often and abused by owners. So having a way to easily change it out is an advantage in my eye.
On the throttle mech i don't have any problems with travel. but your point is in the back of my head so i'll keep that in mind. I prefer using 8-32 screws with locknuts, opposed to rivets. this way anybody can easily change the throttle assembly. These things get hacked on often and abused by owners. So having a way to easily change it out is an advantage in my eye.
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Here's another potential victim, a 3.5 hp Tecumseh H35. I'm not a big fan of these, as they don't seem to have nearly the power of the 4 and 5hp models. Does this warrant a re-do?
Looks like it's from 1978.
Here's the head removed. I would say this motor got some usage. Not a ton, but more than the orange HS40 for example. Not as much as the H50 though.
Note it has a second small PTO shaft, as did the first motor in this thread. I get these motors running, and then use the Hacksaw tool seen below to cut the small shaft off clean. Notice this is a "side pooper" model motor. Also for some reason this motor has a mix of white removable sheilds and a black short block. I don't have the history on this motor (it was a "freebie"), so i don't know where it has been.
Looks like it's from 1978.
Here's the head removed. I would say this motor got some usage. Not a ton, but more than the orange HS40 for example. Not as much as the H50 though.
Note it has a second small PTO shaft, as did the first motor in this thread. I get these motors running, and then use the Hacksaw tool seen below to cut the small shaft off clean. Notice this is a "side pooper" model motor. Also for some reason this motor has a mix of white removable sheilds and a black short block. I don't have the history on this motor (it was a "freebie"), so i don't know where it has been.
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i like those H35's. you might want to change the cam and side cover to make it into
a minibike appropriate engine. i would heed what markus and the good dr shop
teacher said about removing the governor spring. all the effort the engine generates
trying to reduce the rpm is dissipated as heat by that funky plastic gear and slip ring
with that wire in place. cool!
a minibike appropriate engine. i would heed what markus and the good dr shop
teacher said about removing the governor spring. all the effort the engine generates
trying to reduce the rpm is dissipated as heat by that funky plastic gear and slip ring
with that wire in place. cool!
By chance do you have an hs40 ctrankshaft pints/condenser style part number so I can go looking?
I could turn it but it’s a lot of work to do for one crankshaft. Last time I did, I had three. it made more sense to do all the set up.
To that point, when did the crankshaft change so that the h35 and HS40s were the same?
I could turn it but it’s a lot of work to do for one crankshaft. Last time I did, I had three. it made more sense to do all the set up.
To that point, when did the crankshaft change so that the h35 and HS40s were the same?
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Theres a whole thread just recently posted on how to "restore" a Tecumseh. The thread went way off track but started out featuring a mid 1970's HS40 with 3/4" crankshaft in it so you could maybe check out the numbers on that engine if you can still make them all out through the powdercoating to find the needed crankshaft numbers you are looking for :thumbsup:
crankshafts did start to cross fit until the electronic ignition era with larger taper flywheels, and not on all versions so you have to research engine and part numbers to cross reference fitments.
crankshafts did start to cross fit until the electronic ignition era with larger taper flywheels, and not on all versions so you have to research engine and part numbers to cross reference fitments.
If you look at the pictures I posted of the motor numbers on the engine that was powdecoated, you can clearly see the numbers. Powder coating does not make the numbers unreadable
The big problem I have is that when I look at a crankshaft I don’t see part numbers on the actual crankshaft. That makes things a bit difficult
The big problem I have is that when I look at a crankshaft I don’t see part numbers on the actual crankshaft. That makes things a bit difficult
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Another great day on craigs list! $40 for a Columbia snow blower with a perfect HS50 engine. It's black (anything but orange!) and has a 3/4" shaft that is even already drilled and tapped. It's a points/condenser model, looks like from 1977. Note the snowblower is by Columbia. The same people that marketed MTD minibikes. pretty cool. Will do the standard conversion and make it a minibike ready engine.
Lucky score. I’m envious actually.
Any thought to resurrecting the snowblower body with another engine (Predator, etc), refurbishing it and flipping it for $$$?
Not necessarily making it beautiful, but only functional. Seems a shame to scrap the machine.
I’m late to the collectible minibike game. I’ve only got one (Rupp) that originally came with a Tecumseh (had a Briggs when purchased) but I’m mainly interested in Tecumsehs because they’re the other. Kinda like being a Chevy guy and looking into Fords.
All you guys have made Tec minibike engines scarce. :no:
Any thought to resurrecting the snowblower body with another engine (Predator, etc), refurbishing it and flipping it for $$$?
Not necessarily making it beautiful, but only functional. Seems a shame to scrap the machine.
I’m late to the collectible minibike game. I’ve only got one (Rupp) that originally came with a Tecumseh (had a Briggs when purchased) but I’m mainly interested in Tecumsehs because they’re the other. Kinda like being a Chevy guy and looking into Fords.
All you guys have made Tec minibike engines scarce. :no:
I'm running an HS50 snow blower engine on my El Tigre, it's fast and will probably hurt me eventually. Here in northern Ohio snow blower engines are plentiful, the special ones are lighted.....I've never had to pay for one either. Just got a 6 horse Briggs last week from a snowblower in a neighbor's garbage. Perfect for an old Tote Gote or something. :thumbsup:
I have not been able to find a Tecumseh from a Snowblower with a lighting coil. i would love to find one. Mostly because i want to come up with a way to modify any tecumseh to use a lighting coil. i can make the coil, i do that in another avocation i'm involved with. But my understanding is that the flywheel is different. Until i see one in person though, i can't comment or attempt to make the modification. I think a lot of people would like it if i could come up with a solution to this problem...
Did some sand blasting work on the 3 motors. I don't go nuts with this process, just try and get the major crap off. On the orange motor it's more time consuming, because the thing is orange! but i'm getting ready to paint the blocks. And the removables will be sent to the powder coater (he's on vacation this week.)
