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7018 Repower


DTS

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The Kohler K361 in my 7018 Sovereign started to lose power, then would not start.  I took off the air filter to try some starter fluid, and I noticed fuel blowing out of the carburetor.  So, I think I lost the intake valve seat.

I am not a mechanic, so I chose to attempt a repower instead of a rebuild.  I decided to try a Predator 670CC engine from Harbor Freight (It was the only one I could afford).  I saw several posts of simplicity repowers using the predator engines, but they were all in larger tractors (7100 series or larger) so it is a bit of a risk.  Took some quick measurements in the store, and I think it will fit (except for the muffler - may take some creative fabrication.)

I measured the height difference of the drive shaft. between the Kohler and the Predator at 1", so I made a mounting plate using 1/4" steel plate and 3/4" square tubing.  I found an adaptor in Bay to connect the kohler drive shaft to the predators-l64.gif.c8d38504d1d0ba3e3b69ca264b9b2317.gifs-l64.gif.c8d38504d1d0ba3e3b69ca264b9b2317.gif.

I had to notch the lower frame a bit for the oil filter and wiring port, and trimmed the upper frame for the Predator faring.  I am also converting the tractor to a hydraulic lift at the same time (Might as well do it while I have the tractor disassembled.)  This is as far as I have gotten.  Will post more later.

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Don't throw away the old engine. If you don't want to rebuild it, I'll bet you could sell it for more than you might imagine to someone who will. Good luck, Dave

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Hello I did a Predator 22 hp repower years ago and am happy with  the engine . 

Mine smoked like crazy when I went up a steep hill, the crankcase vents back into the carb, and dumps the oil vapor into the carb 

one solution is to run a slightly lower oil level .

I ended up  removing the crankcase vent from the carb and adding an automotive  aftermarket breather.

If it starts to smoke   you will have a clue

I also made a smaller muffler so it would fit under the hood 

Thanks Ken in Mi

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Edited by maxwood
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Ken

 

Thanks for the info.  I read your post before I decided to go ahead with the Predator.  That is what gave me enough confidence to attempt it.

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OK, I have a technical question.  I measured the height of the drive shafts of both engines.  The predator was 1 inch lower, so I made my mounting late 1 inch high (1/4 inch plate welded to 3/4 inch square tubing.)  When I went to try to mate the engine up with the drive shaft it seemed like the engine was too high.  It takes more force that I expected to get the motor and drive shaft to line up.  Should the drive shaft be under tension?  Or do I need to lower the engine?

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The original plate that was used to elevate the Triad engine was not quite an inch.  If I remember correctly is was 7/8" or 15/16" or something just under an inch.  Depending on what you are using for the "couplings", there may be some degree of alignment run-out allowed.  On the early 7000 series, there were two flex disks.  On the later 7100 series, there was one flex disc in the rear of the driveshaft & a rubber "puck" at the front.  As Dave stated above, there shouldn't be any "tension" per say.

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Hello, On the end of the driveshaft is a yoke that slides on the Bevel gearbox  shaft ,

this is designed to move forward or back to allow for adjustment . 

loosen the set screw  and if it is not to rusty it may slide . 

worst case scenario is remove the yoke and clean the shaft with sandpaper .

Hope this helps.

Thanks Ken in Mi

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5 hours ago, ShaunE said:

The original plate that was used to elevate the Triad engine was not quite an inch.  If I remember correctly is was 7/8"

Command crankshaft height is 6.125". Triad & Predator crankshaft height is 5.25". Triad motor mounting plate is 6.125" - 5.25" = 0.875"

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I figured out my problem.  Two bolts on the engine were resting on the frame and the engine was not setting all the way down.  My mounting plate is 1”.  (Picture attached). Do you think the extra 1/8 inch will be a problem?

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I did not know that the drive shaft slid in and out a bit.  I had to make longer spacers to get the engine to mate with the drive shaft. See pictures.   The second picture shows the difference in length between the old and new spacers.  
I am worried that the longer spacers will be less resistant to twisting

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8 hours ago, DTS said:

Do you think the extra 1/8 inch will be a problem?

Yes. The Flex discs are not meant to take up 1/8" of misalignment. You need make it 7/8" or you will have problems. Ask @ShaunEif he still has an extra Triad mounting plate.

For driveshaft connection, I think you want to use a:

Predator 670 Kohler Adapter from Performance 670 then,

Kohler Front Drive Adapter, P/N 24 029 09-S (takes the place of the spacers) then

fiber flex driveshaft disk and driveshaft.

Assemble driveshaft assembly to establish final front to back engine location with full engagement of driveshaft adapter on BGB input shaft.

 

 

 

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Also pay attention to the orientation of those "special" washers that make contact with the flex disc.  The "beveled" or "round" edge should be in contact with the flex disc to reduce the potential for damage.  It appears you have the outer ones correct & the inner ones incorrect in your pictures.

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That adapter is used by both Command and Triad Sovereigns.  They are available on eBay occasionally or new from Kohler.

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