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616-4040-620-9020 re-powers


Al

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Hi, Got a chance to work on the 616 repower today. Have been so busy it has been on the back burner. Got the adapter plate made and cut the frame at the front axle as far as I want to go, and still can’t get the Ch25 to set in. Pulled it and put in a 20 hp Vangard, just as many problems. The TH18 twin cam would be the easiest as far as real estate goes. I have all of the outline drawings back out for some other makes too. I prefer to use the CH 25 for a couple of reasons. First I think the tractor ought to have 25HP, next the CH25 is now running in about 300 zero turns as a CH26. A 25 with Bosch fuel injection rated 26. Initial results show nearly 50% less fuel consumption. I expect this engine to be available to individual purchasers next year. What a beautiful option for these stately old girls. We are trying to use the original belts for the clutch and the mower. If I absolutely can’t I might give. Problem: if you raise the engine for crankcase clearance the hood clearance problem gets worse. This application absolutely needs a ducted engine, and when I put the ducting kit on we are in the heat baffles in the hood.. We are going to have to fab. A lot of sheet metal Even though the old Onans were moosey, they are rather short compared to all of the new generation engines and having to use both ends in that wraparound frame is tough. Before I go further, I would like to have some input from any potential users of this kit. Would you just reply to this post and let me know what is important or a problem to you. 1: 25 HP 2: Using the original belts for the clutch and the mower. Then any parts book would get you the right belts. 3 A limited amount of cutting and welding if templates are provided. This is going to be a necessity. 4 Having to modify some of the sheet metal baffles and ducting under the top of the hood. 5 Would a gelcell battery be preferable to an outboarded battery box. We have to fix the battery cooker. 6 How important is the rear PTO? It is a difficult problem, and will probably be an added cost option. 7 Would an oil pressure light be important? 8 Any other item, that might be a problem for you if you were installing this kit. We have been selling the 7100/900 Kohler TH18 OHC kits regularly. All of the people that we have shipped kits to report no problems installing them and they are bolt in. One person said he got home at 5 the engine and kit were there and he was driving it by 8:30. We are going to ship our first 712 / 18 Vangard kit this week. We have done about 5 of these installations, but 4 had an outside muffler. Because of the chance for someone to contact the hot muffler, we had not proceeded to kit this. The last one we did the muffler is under the hood, and all kits will be this way. It complicates the location of the oil filter and these engines will not be able to use the snowblower clutch. The kit we are shipping is going to a customer that has agreed to use our draft drawings and installation procedures. He will then add his comments and we will have to redo the paperwork and before too long be ready to provide these kits for3300-7000 and 700 ACs. We still have a little development work on the electrical part on a couple of applications. The 616 is being a little more challenging, but I guess all of the Grandest Ladies are the hardest to catch. Thanks so much, Al
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Al- My 620 with the CCKB is running well now, and hopefully will not need a re-power for some time, but I guess it is inevitable. I seem to recall that back in the discussion someone noted they had put in a twin Honda but had to lose the rear PTO. Personally, I use mine without any deck or back implements other than a cart, but would prefer to keep the option available if possible, but not at a high cost in dollars or complications. All the things you are trying to accomplish look good, but of overall importance will be price, effectiveness of new engine, ease of conversion and availability of standard parts, whether OEM or otherwise. Good luck in your efforts. Peter
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Al, I think we're all grateful for your undertaking this project. I think the 25 hp is the way to go. I've heard many complain that these tractors were underpowered - even the 19.5 hp models. Personally, I think the 20 hp is good, but 25 hp would be great! The rear PTO is very important to me - as I have many rear PTO implements. Using OEM belts is not really a concern. I never even use the clutch for anything. Limiting the amount of welding and cutting necessary is helpful (but I understand that it is inevitable). I think that if you are successful in this repower, it will be a hot item for a lot of us out here. Frankly, most of us are fed up with the Onan/Cummins (parts availability and cost) situation. Thanks and Good Luck. Jeff
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The Older Onan engines used to say Mcgraw-Edison on them.... looks like Cummins bought them out. I have an 18hp engine that runs just sitting in my garage....... It seems to be the exact same engine as on my dad's Miller Legend Welder....... the engine seems to be an exact duplicate as the one in my 9020. One difference..... trading off a Cast-Iron Block for an Aluminum one with Cast Iron sleeves... I think that someone should try this out because Onan Engines........ Brand new Performer 20 hp cost about 1200 bucks
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I have an AC 720. Blew the engine and was told it wasn't worth it to rebuild it. I bought an Onan Performer 24. An Onan Performer 24 WILL work with some modifications. I have been using it with the new refit for 2 years. It was the closests in all aspects (keysize, distance to crank, width) to any other engine on the market(for that size because I didn't want to go lower than 20hp). Good luck on the 25.
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  • 1 month later...
I have a 720 that needs re-power, after a lot of research I found this information: Cost about $1,200.00 The Robin EH65 engine should fit. You would need an engine mount and flywheel-to-pulley adapter(output shaft looks the same), with the proper headers the Onan muffler should fit. If I read the info. correct Robin developed the Onan V-twin engine (they have identical specs), and cost less. http://robinamerica.com/engines/eh65x.html
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  • 1 year later...
I put a 24HP Honda im my 9020 last summer. I had a sleeve made to fit the original mower clutch onto the crank. On the flywheel end I had a hub machined to boltonto the three blower bolt and mounted the original pulley to drive the trans. and rear pto. I cut the pipes off the Honda muffler and mounted it ahead of the front axle connected by flex tubing. The engine sits on a 3 1/4" plate to get the proper hieght.It work so well I now have a 48" mower behind the left rear wheel driven from the rear PTO to take a 105" cut.
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