[sawyer112]

I. Am looking for crank stub specs for a vh70. Also is there a common motor transplant for these things

Thanks

 

[woodpecker41]

There is no common engine transplant for a 60/70/100. Crank is a standard 7/8 by 3 5/32 long crank. I might be wrong on the fraction part. The hard part of the swap is trying to get the crankshaft center line in the same place as the Tecumseh and frankly I do not know how to do that. I will enclose my 70s picture. It has been repowered by a Briggs 675 from a pressure washer but I am no longer able to use the PTO or any powered attachments with the tractor. If you try a swap you need a heavy flywheel engine not just a lawn mower engine that depends on the blade for starting weight. Welcome to WFM. Roger

 

[sawyer112]

Hey thanks for the welcome. I was thinking About an eight hp Briggs. My tractor is in pristine condition so I would like to maintain full ulitization of it. As far as getting it centered I think if you measured the mounting circles and did the math you could come fairly close.

Hows that 675 seem for power?

Sawyer

 

[woodpecker41]

675 seems to be equal in power to the original engine for power for what I use it. When Briggs HP rated them they were 6 to 6 3/4 HP. It will spin the lug tires when I use it to push mulch a a bit of dirt with out stalling. The back of that engine is touching the back motor mount metal and the crank centerline is 3/4 of an inch about ahead of where it should be. Some of the other older Tecumseh may fit. Most Briggs 8 HP and ups have 1 inch crank shafts. Good luck with your search. Roger

 

[sawyer112]

I found an old Briggs 8Hp with the 7/8" crank. I think I'm gonna try that on it.

 

[bltee]

I emailed you some dimensional prints. Hope that helps.

 

[chevy2003]

Hi guys! I have a 70 that I bought recently. It has been parked for about 8 years. Was told engine ran when parked, but was frozen solid at sale time. Took it apart and freed up engine, was just rust and gunk from sitting. Now, I'm assuming when I get it all back together that is should run, but I have wondered about the re-power thing too, and have read about all the issues. I don't have a 100, but aren't they almost exactly the same as the 70 except for the engine and hood?? Was wondering if the power/pto from a 100 would sub for the 70? Or if the PTO from a 100 would work on a newer B&S engine in a 70?
Just thinking 'out loud' --
Thanks!
rayg

 

[woodpecker41]

A 100 engine might work but they are harder to find an engine for than an engine for a 70. The 100 chassis is a bit different than a 60/70 one. Someone here tried to build a 70 on a 100 frame and finally gave up. Roger

 

[mikeduwe]

I put an 8hp (19ci displacement) in my 70. Its an inch bigger in every direction than the 7hp Tecumseh, but I put a lot of effort into making it look factory in there.

I got rid of the isolation mount system and welded in a 1/4" plate like the 60 did.

I had to rework the clutch and brake linkages and move the battery box back so it all cleared the engine. Adapted the Tecumseh air cleaner to fit the briggs carb.

I was working on putting 70 sheet metal and driveline on a 100 frame, but found out the 100 frame I got was bent and just went ahead and modified my 70 to fit the engine.