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Kenh

Predator engine swap

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Kenh

I was thinking somebody here did a repower using Predator engine from harbor Freight.  I'm just looking for any problems that came up and solutions that need to be found.  No use reinventing the wheel.

Thanks!  

 

Ken

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rich_kildow

I put a 22hp twin in a 7117, and there were no real issues to speak of.  But you're going to need to figure out 3 keys parts:

- Flywheel adapter - The small engine warehouse one I used is no longer available, but the engine does have the same bolt pattern as a Honda GX670, so is probably something out there.  

- Triad mounting plate to boost the engine.  They are out there but you could also accomplish this with a piece of steel of the appropriate thickness, drilled in the right locations.  I could get you this thickness measurement if you need it.

- Muffler - Either hack your hood or come up with a different muffler.  I have a link to my exhaust build thread in the link below.

The photobucket debacle of 2017 nuked all my pics from the forum, but I still have them and I will work on getting them back up if you give me a few days.  

Repower Thread

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Alltractoredup
23 hours ago, wwbragg said:

If I am not mistaken, the 900 series originally had a 16 HP motor so you will probably want to use the 22 HP predator.  

Definitely going 22 hp

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rich_kildow

I've been very impressed with it thus far.  Document your swap for us, especially the driveline.  There are lots of ways to accomplish lifting the engine to the right height, and the muffler is just a choice between cut the hood or minimal welding on another muffler.  

The driveline seems to be the issue that keeps changing.

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wwbragg

I had to repower my 707 with a Briggs 217807.   The muffler shop made a custom exhaust for around $40 or $50.  Then I topped it off with a pair of VW bug chrome tips.

Then I bought a Harbor Freight pipe bender and built the one shown in my previous picture.  Piece of cake.

 

2013-11-09 18.15.43.jpg

Edited by wwbragg
expansion

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TomC

So, Ken, it looks like your adaptor is exactly the same as the one that Small Engine Warehouse provides for $75 now. Part at http://www.smallenginewarehouse.com/GH618-FLY-H.html and drawing at http://www.smallenginewarehouse.com/core/media/media.nl/id.247582/c.3401423/.f?h=25d21c7253ea2013ad4a

If I'm understanding this right, $700 for a Predator, $75 for the adaptor, and maybe a combination of some creative tubing from the auto parts store, some motorcycle mufflers from ebay, and advice from here and you should be repowered. Of course, plus the fun rewiring.

 

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gravey72

If I remember correctly I checked in late winter early spring and small engine warehouse had the same 1 in stock but when you try to buy your out of luck. I tried contacting with no luck. I believe Lloyd got ahold of them and they said they would make them in about a month. I kept checking all summer and have decided to go in a different direction

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wwbragg

I'm just spit-ballin' here but why couldn't you adapt a driveshaft coupler from a 725 (Simplicity 2154194)?  Just drill one side to match up to the three bolt holes in the Predator flywheel.  There is one on ebay for $35 + at https://www.ebay.com/itm/Allis-Chalmers-Simplicity-Driveshaft-Drive-Shaft-Coupling-725-B-1-Tractor/182714915864?hash=item2a8aa85c18:g:UEEAAOSwHk9Zj6Oo.

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wwbragg

OK, so make it fit.  But it might not work anyway since what ever you use will have to be wide enough to hold the fan to the flywheel.  How wide is the impeller tray on the 22 HP?  It will have to be that wide.

And what size are the three bolts that hold the impeller tray to the flywheel?  They will no longer be simply holding the fan, they will now have to hold the adaptor that is transferring 45NM of torque (or 33 ft lbs) to the rear wheels.  The flywheel on the 22 HP attaches differently than my 13 HP.  I don't think the flywheel nut can be used to hold the adaptor.

My 13 HP had 7mm bolts that held the starter flange to the flywheel.  I drilled them out to take a 5/16 bolt.  To tell you the truth, I am still a little worried about them - - - -should have gone 3/8.

Edited by wwbragg
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maxwood

Hello, If you look at my first reply  above ,is a link to my build  with lots of pictures  It may answer some of your questions .

 

Rich Kildow also did a thread on his repower

 

Thanks Ken in Mi

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bnolte

It might be a little late to the party but an outfit called Performance 670 sells a flywheel adapter to attach a Kohler driveshaft to the predator engine.  I just got one for a John Deere Ztrak engine swap, which had a  blown up Kohler Command 20. I still need to figure out how to raise the engine and offset it. The crank centerline of the Predator is 7/8" lower than the Kohler, and offset to the left slightly. Fortunately everything runs off the flywheel, so I don't really need to worry about the crank end, but I might have to worry about the muffler. 

5c950d429e3ee_predatoradapter.thumb.jpg.b567a3bc5ce7934925afe20410166240.jpg

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