Repowering Snapper 21" Hi-Vac with Predator engine

Erubi

Forum Newbie
Joined
Aug 15, 2013
Threads
3
Messages
8
I love my 1993 Snapper self propelled mower. Have done a lot of work on it over the years and finally the original engine bit the dust. I got a Predator from Harbor Freight and ordered the 7/8 snapper pulley and 7/8 snapper blade adapter. I have limited mechanical ability and have learned a lot along the way. I didn't know about keys and keyways and didn't realize that the shaft and blade adapter are different. Crankshaft 3/16", blade adapter 5/32". Is there a happy ending here? Is there another blade adapter that I can substitute?

My other challenge is mounting the engine. Only 1 hole on engine is threaded. Can I buy self threading bolts? If I need to tap, what size tap?

Thank you in advance for your help. In the past, I would call my dad, the best mechanic, unfortunately, he passed away almost 6 months ago. He taught his daughter how to do a lot of things, but there was never time for everything else!
 

mechanic mark

Lawn Pro
Joined
Jul 15, 2013
Threads
175
Messages
7,381
A local machine shop can fix you up, just give them a call.
 

Erubi

Forum Newbie
Joined
Aug 15, 2013
Threads
3
Messages
8
Thanks Mark! Took 'er in this morning!
 

Snapperfreak

Well-Known Member
Joined
Dec 13, 2011
Threads
22
Messages
676
  • / Repowering Snapper 21" Hi-Vac with Predator engine
Thought I'd dig up this thread to ask how the snapper turned out. All fixed up and back in service?
 

Erubi

Forum Newbie
Joined
Aug 15, 2013
Threads
3
Messages
8
  • / Repowering Snapper 21" Hi-Vac with Predator engine
Thought I'd dig up this thread to ask how the snapper turned out. All fixed up and back in service?

Hey Freak, thanks for asking... Having trouble finding a machine shop! Most seem to be geared to commercial customers. I did try grinding down one side of the 3/16" key to fit the 5/32" keyway on the adapter with my dremel. It's not a real tight fit and I'm afraid vibrations would be a problem. I don't want to have to go to a different adapter and lose the quality of the ninja cut! Any suggestions?
 

Snapperfreak

Well-Known Member
Joined
Dec 13, 2011
Threads
22
Messages
676
  • / Repowering Snapper 21" Hi-Vac with Predator engine
I agree, a tight fit is indeed necessary for that adapter. We don't want anything vibrating loose! I wonder if, since you're not having much luck with a machine shop, if just a mower shop would be able to get that fixed up for you? Worth a shot at this point. As for the non-threaded holes on the engine, as long as the other holes go all the way through you could just use nuts and bolts to attach it to the deck. Good ones though like grade 8. In fact, on my Briggs 5hp commercial engines I've only found one threaded hole also, I use bolts on other holes. I've never transplanted an engine other than from one snapper to another. I suppose a last resort, since you've already spent the money on the predator engine, would be to find an engine either off of another snapper that's in good shape or a new engine from online that would bolt right up to your deck with the correct adapter already on it. I think small engine warehouse dot com is a site to check if you go that route. Hope this works out for you, you do have a good old mower and would be great to get it back in shape!
 

Erubi

Forum Newbie
Joined
Aug 15, 2013
Threads
3
Messages
8
Happy ending! Had to go out of town, so I took engine and blade adapter with me. Found a machine shop who made me a step key. I tapped the holes on the deck and screws worked perfectly. Started on first pull and even at half throttle ran right through tall grass. I probably spent more time and money getting this engine to work, but I learned a lot, and enjoyed seeing it work! End of season here, so will have to see how Predator holds up next year!
 

BlazNT

Lawn Pro
Joined
Apr 26, 2012
Threads
28
Messages
6,973
It will not last long if you continue to run it a half throttle. ALL lawn mower engines are designed to be ran at full speed. It is a cooling thing. It will over heat and destroy the engine if you run it less than full speed.

Congratulation on the swap.
 

Rocky J

Well-Known Member
Joined
Oct 12, 2016
Threads
0
Messages
110
 
Last edited:
Top