Predator 22HP Engine Swap. Who has done one???

[USHorse 41]

Sorry....for the PTO

[WildmanC120 615]

42 minutes ago, USHorse said:

Sorry....for the PTO

So I ran power from battery to inline fuze holder, to switch then switch to PTO.  PTO grounded to engine. 

[mpoore 29]

I know this is an old topic, but  I am hoping someone can clarify some things for me. I am attempting to replace a KT19 Series I in a C-195. The 22hp Predator seems like a good option given there are not a lot of options.The documentation is not as detailed as I would like, but I see no indication of ball bearings in the version of the engine being sold today. Some others posted it might have ball bearings. That could be an earlier version. They do not list the alternator output, so I cannot confirm that it is sufficient for an electric pto, but it would seem that it is since that's what others have done. I do see an internal thrust washer in the diagram. Has anyone tried to replace that with a torrington bearing? I wonder if there is enough room because that might be a way to use the manual clutch. Lastly, I am guessing that Predator engines share parts with a brand name engine. I see it advertised to replace a Honda GX630 or a Vanguard. I doubt it is a Vanguard clone because those have ball bearings.I would like to know I can get parts from other sources than HF. Being stuck ordering parts from HF is enough to hold out a little longer for a deal on something better supported. I have a K532 that I would love cram in there if I could find a governor for it. Ebay sellers are asking $200 for the governor. The cost of a governor and a rebuild kit is getting to the point that a new Predator is tempting.

[pfrederi 21,107]

Electric PTOs draw less than 4 amps

[mpoore 29]

If its only 4 amp, then it should not be a problem. Another post made me think it was around 10 amps, which seemed like a potential problem depending on alternator output.

[pfrederi 21,107]

18 hours ago, mpoore said:

If its only 4 amp, then it should not be a problem. Another post made me think it was around 10 amps, which seemed like a potential problem depending on alternator output.

Electro 12s had Electric PTOS lights and a lighter on a 10 amp charging system.

[mpoore 29]

I bought a Predator 670 for my C-195. The plan was to use an electric pto clutch, which will be delivered tomorrow. The best fit I could find for the 1" shaft along with a comparable sheave diameter draws 6.5 amps. I thought I might still be okay until I learned that the charging system on a 670 is 3 amps. I should have known the charging system sucked or they would publish the output. Instead, it is not listed anywhere. I guess I am now stuck trying to install a charging upgrade. One issue is parts interchange. It looks a lot like a Honda GX670, but the only way to tell what interchanges is probably testing.

[mpoore 29]

I have another update. It turns out the Predator engine probably puts out more than 3 amps. There are 3 stator coils. The Honda 20 amp configuration uses 3 coils. A 3 amp system should be one coil. However, the rectifier/regulator is at best 10 amps. I ordered a 20 amp regulator and stator. I am hoping it will bolt on and get me a 20 amp system. There is a 26 amp conversion kit for sale for $250 that includes a new flywheel with the regulator and stator. 20 amps should be more than enough for me so long as the Honda parts fit.

 

The only other known issue is hood clearance with the exhaust along with the exhaust outlet pointing back toward the driver. If you want to be able to close the hood and not cut the hood, some sort of modification to the exhaust is required,

 

The Predator engine is close in footprint to a Kohler. The center line of the PTO is about 1/2" lower than the Kohler making a 1/2" mounting plate a perfect solution to both mount the engine and align the PTO. I have read, but cannot confirm that it is important that an aluminum block engine be mounted on a plate rather than using risers. The Kohler bolt holes in the frame are in the wrong position, of course. The mounting plate will only require some simple welds. It also adds enough weight to the replacement engine that it is very close to the weight of the KT-19, which keeps the weight balance close to original.

 

The purpose of these updates is to help someone trying to do a similar conversion and what issues need to be overcome. Hopefully, someone finds it useful. I hope to follow up once things a further along.

[mpoore 29]

I have some photos to share in case someone is trying to do this repower. The first photo shows the adapter plate. It is 1/2" thick and about 10" x 10". The reason I chose 1/2" is that it puts the pto at exactly the same height as a KT-19 mounted on the original frame. You can use a smaller plate that does not stick out as far on the left side (photo right). I did this so that the plastic fan shroud is protected on the bottom. I mounted the plate to the bottom of the engine and slid it around on the frame until the belts aligned and fit properly to avoid using a different belt size. The face of the engine block is just about flush with the right frame rail edge.

 

I am not proud of the exhaust, but it was as good as I was going to achieve in the time I had. I cannibalized the cylinder head flange and reinforcing straps from the exhaust that came with the engine. It turns out that 1" EMT pipe is a perfect fit for the flanges and I was able to weld on a 1" NPT nipple on the outlet to mount a standard muffler. At least the noise is aimed away from the driver (me). Those are off the shelf 45 degree bends. A 90 degree bend would interfere with the hood unless you use some straight pipe first. If I had a 1" bender, I would have probably done it a little differently. It can always be changed.

 

So far, I can say that this is not as easy as I thought it would be. The issues can be grouped into 4 categories.

 

1. Mounting the engine.

You will need a welder and preferably a drill press. Possibly a plasma cutter.

 

2. Exhaust.

This is up to your personal taste, but probably going to need a welder. I used a lathe to bore the pipe nipple to fit the EMT before welding.

 

3. Drive sheave and clutch.

I used these parts:

https://www.amazon.com/dp/B0DPXNFMT5?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_1

https://www.amazon.com/dp/B07YBD2RGK?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_1

You will need a CW clutch since it is mounted with the sheave facing the engine. The drive sheave is the correct OD, but I did have to bore the ID and broach a new keyway.

 

4. Wiring.

The biggest issue to overcome is that the Predator uses magneto ignition. That means that instead of providing battery power to the coil like on the Kohler that the key switch needs to ground the magneto and also power the fuel solenoid. I have not gotten very far with the wiring yet as I am waiting on some automotive relays to arrive. You will obviously need to wire the PTO with a switch. Adding some circuit breakers or fuses is highly recommended. Give that the OEM wiring is 44 years old, I decided the rewire the entire tractor to ensure reliability. As mentioned in a previous post, I also replaced the stator coils and regulator. I may have wasted my time and money, but I could not figure out what the original output was without testing it. I thought it might have been 3 or 10 amps when I decided to upgrade it. During disassembly I noticed that the circuit breaker for the regulator is 25 amps. What I did not want to have to do was finish this thing and then find out that the charging system had to be replaced. Now, I know what I have, which is a 20 amp charging system.