Replace motor on MTD 5hp chipper shredder—shaft?

[Modrob]

MTD 5hp chipper shredder that I want to replace the motor with a new (but about 6 years old in box) Harbor Freight 6.5 hp motor.
Best I can measure, I get 5/8” diameter shaft on the HF, but the original motor has a 7/8” diameter at the end of the tapered shaft. I’m seeing lots of adapters out there, but all are 3/4” to 1”, and a few have a taper to them. Anyone else run into this?

 

[Alan W.]

Ive got one with a bad motor that was given to me. Have been looking on YouTube and saw where some people have got adapters.
Cant remember the exact videos.
I was thinking about rigging it up to my pto.
No more choking down on a small twig.

 

[Menagerie-Manor]

MTD 5hp chipper shredder that I want to replace the motor with a new (but about 6 years old in box) Harbor Freight 6.5 hp motor.
Best I can measure, I get 5/8” diameter shaft on the HF, but the original motor has a 7/8” diameter at the end of the tapered shaft. I’m seeing lots of adapters out there, but all are 3/4” to 1”, and a few have a taper to them. Anyone else run into this?

Shaft size on the HF 6.5 is 3/4" as I just replaced a splitter engine. Your old shaft should be 3/4".

 

[Modrob]

Shaft size on the HF 6.5 is 3/4" as I just replaced a splitter engine. Your old shaft should be 3/4".

Hmmmm…I held a tape measure under the shaft and tried to line up with both sides of the shaft to come up with the 5/8”…I’ll put a micrometer on it shortly and see what I get for sure…

 

[tomplum]

You wouldn't want to use an adapter on a chipper shaft. What you could do is check that model and see if certain ones were built with the impeller that fits and use that. I dunno if that is worth your will on a small chipper. I've run into this before on motorized assist baggers.

 

[Menagerie-Manor]

Hmmmm…I held a tape measure under the shaft and tried to line up with both sides of the shaft to come up with the 5/8”…I’ll put a micrometer on it shortly and see what I get for sure…

I put a micrometer on the HF 6.5 earlier today, came up 3/4.

 

[Modrob]

I put a micrometer on the HF 6.5 earlier today, came up 3/4.

I mistakenly ID’d my motor as a Predator—after a better look I find it’s a “Starter USA Professional” model. (Must have been before Predators) …and another label says it’s a “gosoline” engine!
It’s shaft mics out at .62 mm or 5/8”.
The original MTD final shaft end mics at .87 or 7/8”.

 

[Modrob]

I mistakenly ID’d my motor as a Predator—after a better look I find it’s a “Starter USA Professional” model. (Must have been before Predators) …and another label says it’s a “gosoline” engine!
It’s shaft mics out at .62 mm or 5/8”.
The original MTD final shaft end mics at .87 or 7/8”.

 

[Modrob]

After more consideration I’m going to leave it alone—go back to the original motor. Got a new carb ordered for it and that should get it back up to snuff.
Thanks for the help and interest.

 

[stevem5215]

Unless the new carb is a chinese clone copy. Then you might want to regasket the original instead. Those Chinese "new" carbs aren't usually very good.

 

[Modrob]

Odd, but I’ve replaced carbs on a couple of lawn mowers, small tractor, and chainsaw with cheapies and so far so good. But yes, I believe it would be better with OEM parts. But EXPENSIVE. When I can, I’ll get the good stuff. For example, I’m having to do a lot of top end work on a finicky Kohler 25hp, so I’ve been using OEM on it—sure don’t want to have to tear it down again as it’s on an articulated tractor with hydraulics…
So…for the small stuff, the Chinese units get me by…

 

[twb53]

Modrob, I am not sure if you still need information on engines with MTD tapered shaft. Assuming you might, briggs no longer makes the engine with the tapered shaft. MTD and Troy-Bilt now have a relationship with a Chinese manufacturer for their engines. I found on ebay a Zongshen Engine 6hp 208cc with an MTD tapered shaft. If you search ebay for this, it will pop up for $135.45 free delivery from Small Engine Warehouse. In looking at the photos, it looks like a standard MTD taper 7/8" to 1" inch. There is a contact seller link. I would think they could give you the complete dimensions on the crankshaft and mounting bolts. In looking at the engine, the form factor matches what is on my Troy-Bilt chipper shredder. While it might not be the best quality (who knows), at $135 it is not a big risk. I am thinking of buying one and keeping it as a spare. It only takes 1 rock in the chipper to shear the crankshaft. Hope this might be helpful

 

[Richard001]

twb53,​

Welcome to TBN.
I hope you realize that the previous post is 1.5 years old.

Richard

 

[Richard001]

Modrob, I am not sure if you still need information on engines with MTD tapered shaft. Assuming you might, briggs no longer makes the engine with the tapered shaft. MTD and Troy-Bilt now have a relationship with a Chinese manufacturer for their engines. I found on ebay a Zongshen Engine 6hp 208cc with an MTD tapered shaft. If you search ebay for this, it will pop up for $135.45 free delivery from Small Engine Warehouse. In looking at the photos, it looks like a standard MTD taper 7/8" to 1" inch. There is a contact seller link. I would think they could give you the complete dimensions on the crankshaft and mounting bolts. In looking at the engine, the form factor matches what is on my Troy-Bilt chipper shredder. While it might not be the best quality (who knows), at $135 it is not a big risk. I am thinking of buying one and keeping it as a spare. It only takes 1 rock in the chipper to shear the crankshaft. Hope this might be helpful

I think that this is a AI bot post. I could be wrong.

Richard