Simplicity 4040 Onan Engine Parts & Problem

[shoman]

Help! Have a '72 (app) Simplicity 4040 without the engine sticker. Engine is 16.5 Horsepower Onan, according to the Owners manual. I have several problems: 1. Need Points & condensor, and gasket for carb. Local Simp. dealer claims they don't carry Onan parts. Anybody know a source? I live in South/Central Michigan, Hudson. 2. Also, tractor had been left outside not running for a year. Got it to run, and well, when it suddenly developed a problem. Runs like a watch at idle, but with throttle it bucks, snorts, backfires, and dies. Points seem to arc continually, replaced condensor, (with an old one off my Case 446), but problem continues. Anybody have any ideas? Have a feeling new points would help. Thanks, George Holmes

[jackcobb]

Sandy Lake Implement, Sandy Lake PA (who advertises on this site) has all the parts you need. The Onan is the most finicky, tempermental engine in the world I think when it comes to it's ignition. I'd order new points, condenser, plugs and plug wires from Bill. You have to be good at setting the points, and Bill is an advocate of proper timing. I have always lucked out just with new points/condenser and plugs, but you might buy a manual from him and learn how it is timed too. Good gas and "SeaFoam" (an additive, which often gets praise on this site) is very benificial too. Also make sure your fuel pump is working. Low pressure electric pumps are available, if you want to by-pass the mechanical. If none of this works do a compression test, valves? Then carb if thats ok.

[JP]

Hiya George, Welcome to the 'gang'! The first thing is, You shouold have a CCKA-MS 2026G Model engine in it. The best way to really tell is the carb. If it's a side draft It's a CCKB. If it's a down draft it's a CCKA. There are a few other differences, but that'll be a search the forum job for you. The points # is 160-0002, They should be around $10. The condenser is 312-0069 & around $6. Which gasket? These engines are real sensitive on point settings and they seem to be plug sensitive too. If your close to New Hudson MI, There's an Onan dealer there. Make sure you keep one hand on your wallet & the other on your shirt, he'll try to get both. 8-) Is the carb been gone through? Good plugs & wires? Air filter? I'd do the points & get them as close as possible. Let us know......... Take Care, JP

[shoman]

Thanks JP & Jack(?) Now I have all the information I need. The carb is a down-draft, so I guess my engine is a CCKA...I found an Onan engine parts site online, which seems to have everything a good prices, too. I was able to figure out the timing, the guy I got the tractor from found the owners manual yesterday. What a wonderful resource this site is! Thanks again! PS That Onan site I mentioned has engine manuals, it's address is: http://www.perr.com/onanstore.html... Hope it's of some use... George

[gretsch]

I think George has the timing figured out. But for others that might not know, you can use a timing light just like you do on an automobile. The timing guide is above the front pto shaft on a bracket and the timing mark is on the front clutch (this mark indicates 20 degrees offset - not sure if advanced or retarded). To adjust the timing, just remove front plate off of points box, loosen mounting screws, and slide left or right to align marks. From personal experience, if the timing is off the engine can act extremely finicky.

[shoman]

Actually I didn't know this method of timing. I was using the TC Mark on the flywheel, which you can see by raising the hydraulic cooler at the rear of the motor, and the scale of degrees on the rear engine housing, on top, visible through a hole in the cooling shroud. The timing light does work fine, too. One clue as to my problem is that the timing mark jumps around when using the light. That with the constant "frizzle" of arcs across the points when running hints at the points as the problem. I'm thinking the condensor may be bad, as I think it's function (the condensor) is to absorb the arc which occurs when the points open. Otherwise you don't get a clean and timely discharge from the coil. Does anyone know if this is correct? (what fun) George

[gretsch]

I'm not sure about the jumping around of the timing mark when using a timing gun being correlated to sparking of the points, but it could be I guess. I do know that I always have some jumping around of the timing mark when using one on any engine (including ecu controlled automobile engines). I just assumed it was the inductive pickup design not being absolute.

[UCD]

when the timing mark jumps around with a timing light it is usually an indication of worn timing parts IE. loose chain or worn gears. Anything free is worth what you pay for it This & $1.00 might get you a small Coffee Maynard aka/UCD

[jpknautz]

have you tried www.smallenginewarehouse.com im planning on buying a 22hp twin cylinder for $750 so try them out you might find what you are looking for.

[powermax_paul]

Gretsch, Do you have a CCKB? I think some of the CCKA's do not have the timing marks at the front end like the CCKB's do. Showman, if yours doesn't, you might want to mount a piece of sheet metal with a mark on it so you don't have to lift the oil cooler every time you make timing adjustments. Paul

Paul Kjorlie, The Norwegian

[gretsch]

Paul, Yes, mine have all been CCKB's. I have always heard that the only difference was the carb setup and starter/flywheel setup, so I assumed that they all had the automotive type timing setup.

[shoman]

Guys, \ Thanks for all the help. I think I'm on top of the problem, tho' only time will tell. I ended up taking the point box right out, cleaning everything, filing the points ending with 1500 grit wet/dry, putting it all back. Checked the timing with the marks at the rear, and the front marks(guess mine is a CCKA). Part of the problem was a tear in the top carburettor gasket which allowed gas to be sucked from float chamber into venturi. Tried to repair with silicone form-a-gasket...Didn't work. Made a new gasket out of two layers of file folder, worked fine until a piece of the damned formagasket got sucked into main jet. Off came the manifold for the second(or was it third?) time that day. Put it back together, ran fine for about an hour, did it again. Idled fine, wouldn't take throttle. Pulled manifold and carburator again, cleaned with cleaner, blew it out, put it back together, and it plowed some new ground for next year, so all looks to be good, except for two minor glitches: 1. I'm leaking hydraulic fluid somewhere behind the wheel mount plates under the seat, on both sides. Have tightened everything, which may solve it. 2. Before I got the tractor it would die after mowing for an extended period, then afther a wait would run again. I've not used it to mow, and have also removed about 30 pounds of oil and hydraulic fluid soaked grass and dirt from virtually every part of the engine and frame. Thinking maybe it was just getting too hot. Not to overwork your help, but has anybody had exeriece with this problem? Thanks for all you help George H