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720 Starter removal ??


arnoldir

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Hello All, The 720 saga continues, click no crank, must be solonoid. I've got the engine up out of the frame sitting on a peice of 1/8" plate across the frame rails, been soaking it with degreaser since yesterday (man what a greasy mess) Can someone give me the lowdown on how the starter is bolted to the engine so I can minimize the time spent wrenching. Of course the starter went after I parked the tractor in the middle of my driveway and dropped the loader and box blade. If I have to move it, can I hoist the loader bucket up while having somebody hold the valve lever "up" and will it stay, or do I have use a drill to spin the loader pump ? Thanks folks, happy tractoring.
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Hi, I just finished working on my 720 starter. I don't know about the loader hydraulics, but I know alot about the starter, because I've had it off&on 5 times in the last month. This email assumes you have the 19.5 HP CCKB Onan engine. It is possible to take out the starter with a 9/16" socket, and a 6" extension, by carefully reaching from the bottom (after removing the tractor's bottom sheet-metal guard). However, there is play in the mounting bolts, and it is impossible to see how the starter/flywheel gears mesh while the flywheel cover is on. Therefore, I have some bad news. I found it was easiest and best to remove the engine to get to the starter. Then it was possible to see how the gear teeth mesh when putting it back on. Fortunately, I have even better news. I was able to get an exact replacement for the solenoid from NAPA auto parts for $17.00 and it works great. If you want the NAPA part number, let me know, and I'll get it from home. I have also replaced/rebuilt the charging system and the front axil bushings if you get in to those. -Ken
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I just reviewed the post again and noticed you have the engine out. If you have a CCKB eninge, the starter is held on with two 9/16" bolts located below (on the outside of) the fly-wheel cover. You don't need to remove the cover to remove the starter (see my previous post). Even better, you can leave the starter motor on and replace only the solenoid by loosening two phillips head screws. You may want to use a wrench on the side of the phillips head screws if they were as tight as mine were! -Ken
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Thanks Ken, Glad to hear I do not have to screw with the fan shroud. I'm planning on yanking the entire starter, so I can give it the full internal exam. My thought was to add a backup wire from the output of the solonoid, leading out from the starter so if the solonoid goes again I can jump right to the starter winding.
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Unfortunately, you will probably need to remove the flywheel shround to see if the gear teeth are lined-up properly. This is because the through-holes in the starter are sloppy, and it is possible to have the starter teeth not enguaged enough. I am having two problems with my 720: 1) I need to find a replacement clutch 2) My compression tests at 125 psi, but at idle, the oil fill cap is puffing out oil on my engine. Do you have any thoughts on these problems? Thanks. -Ken
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Hello again Ken, I dug through the crud and found the 2 bolts, removed them, but found that I had to remove the 2 lower shroud bolts and pull the shroud out about 2" to get the starter out. As for a clutch ? I've not had that problem yet, (knock on wood). Puffing oil at idle, sounds like a blocked crankcase breather line, but I'm just taking a guess. Good luck.
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Hey Ken, I need the NAPA Number for the solonoid, mine is shot. Checked the Standard Parts book and there are way to many to chose from. Help !
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The NAPA number is 245-48017JN, cost is $17.81 + tax. I can also get you the manufacturer's part number, if necessary. The solenoid came with the plunger, gaskets, and extra spacing rings. I used one gasket and no spacer rings. Try to keep the plunger area completely clean because it has a very tight clearence. I placed one drop of new 10W-30 oil on my plunger, just for good measure. The ZM-.. part numbers should face outward. I don't know where the original negative battery connection was, but I connected mine under one of the 9/16" starter mounting bolts, so the starter would have a good ground. Be very carefull to angle the positive wire away from the tractor frame. It's a very tight clearence, and if the frame ever rubbed through the + wire, the tractor could turn into smoke. Have a good time. -Ken
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Ken, Is it possible you have a cracked fuel pump diaphram? You might be getting gas in your oil.
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Paul, I don't think so. I recently (less than 1 hour of running ago) re-built my fuel pump and changed the oil. I also cleaned the PCV check valve assembly, it looks good now. My current theory is that the oil re-fill cap gasket is bad, which allows the puffing oil mist to escape. But It's hard to believe the puffing is OK in the first place. Any additional ideas are appreciated. Thanks. -Ken
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Ken, The P/N you provided does not work when entered into NAPA's online parts search, www.napaonline.com Do you have any more details ?
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That number is on my NAPA receipt. I can get you the manufacturer's number from the box, but it's at home and I won't be able to get it until later tonight. I got the manufacturer's number by crossing-referencing it from the Onan part number. The manufacturer's name of the new solenoid is "ZM". Don't ask me what it stands for. -Ken
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The cork-type gasket on the fill/dipstick could be worn but also the tongs that screw into the dipstick tube could be bent out a little causing the lid to not tighten securely. You stated earlier that your compression was very good so I would assume that the same positive pressure that is released by the breather assembly could also escape through a loose lid on the dipstick under normal operation.
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Thanks. I wonder if a large o-ring would fit. If not, I will have to carfully cut a gasket from gasket material. And I'll also ckeck the metal tabs. I'll let you know if that stops the puffing. -Ken
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I'd have to look to be sure but an o-ring may have trouble staying in place. I'd try making a gasket out of an old inner-tube if the cork is worn out.
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For the Onan 19.5 HP, type CCKB engine, the starter solenoid part numbers are: Purchased through: NAPA Auto parts Manufacturer: ZM Manufacturers part number: 245-48017 It comes with the plunger, gaskets, extra spacers, and electrical stud nuts. I used no spacers (only the retainer piece) and one gasket. Thankfully, it has worked perfectly and looks exactly like the original. -Ken
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