318 john deere onan engine

[ Save This Page ] [ Follow Ups ] [ Post Followup ] [ John Deere Tractors Discussion Forum ] [ FAQ ]

SSB Farm Tractor Parts, Manuals & Antique TractorsAftermarket Farm & Old Antique Tractor PartsTractor Service, Repair & Owners Operators Manual ShopTractor ImplementsTractor SeatsTractor Front End LoadersPedal Toy Tractors Farm Tractors For Sale ClassifiedsAntique Tractors For Sale ClassifiedsTractors Forum - Help & AdviceTractor, Gardening, Mowers & Outdoor Equipment BooksTractor ProductsContact Us
How much is your farm tractor worth? Find resale prices for tractors built from 1939 through today, with complete specifications and serial numbers. Save 15% on our Official Tractor Blue Book sale!

Search This Message Board:

318 john deere onan engine

Nick I have a 89 318 John Deere tractor .It has been an excelant tractor.It started having surging problems.I rebuilt the carb Didnt help .It was winter so i took the motor off to check it all out cylinders look great valves are relapped and clearance checked bought a new carb checked the govener out all looked great . Now it misses at an idle dosnt want to take throttle and runs very hot . it has new head gaskets good compression 105 in one cylinder 100 in the other seems to have good spark .I used to be a Deere mechanic but im stumped can someone help me please ? The spec # is p218g-I/10462b tractor # moo318x489095. The tractor dosnt smoke at all .but it is running very hot now . I didnt pull the cam out so i dont see how the timing could be out. Thank you
Dave Nick - I looked in the technical manual for the 318. Overheating can be caused by a restriction in the exhaust, carb out of adjustment, governor linkage out of adjustment, low oil pressure (pump bad or suction plugged), improper bearing clearances, or carbon build-up.

Engine miss causes are plugs, fuel supply, choke, carb adjustment, valves, or faulty ignition system.

Inability to develop full power causes are throttle cable, choke, governor, carb adjustment, plugs, restrited exhaust, fuel supply, ignition system, crankcase vacuum / plugged breather, valve clearance, compression.

One other thing to check is the fuel lines for cracks. A friend of mine has an '86 318 and he was experiencing similar problems. The dealer inspected his fuel lines and found a hairline split where air was being sucked into the fuel flow. Visual inspection does not always reveal such splits.

Hope this gives you some ideas. If you don't have a technical manual (TM1590), you might want to consider purchasing one. Good luck. - Dave

Nick Dave Thank You for the info .I was wandering if you could give the lalve clearance specs and the required compression to run properly Thank You
Dave Nick - I'm going to e-mail the info to you. - Dave
nick Dave im sorry i had the junk mail filter on its off now if you could please send again. Thank You
Bud Steiner I wouldn't be surprised if you find your trouble is still in the carb.They seem to be very sensitive. Sounds like a little dirt still in it.
Kirk Dave,

I was curious what you found out. I have a similar problem with my 85 318.


Larry Kalnoskas Hope you can help me this- I resently rebuild an onan 18hp engine from a 318 JD. I put in .030" pistons and rings, ground the valves and valve seats and shaved .020" off the heads. The problem is the motor won't start. While it is cranking is starts to backfire. I don't think the timing is out because I line up the marks on the timing gears. It has electronic points. I don't have a clue how to change the timing...THANKS FOR ANY HELP YOU CAN GIVE ME ?????
Larry Kalnoskas Clarence-Thanks for the help. You were right it was the timing. Although
I don't know how to change the timing, what happened was there a woodruff
key on the front shaft. This key has an extension on it that runs along the
shaft. This extension fits into a plastic ring that has a cut-out in it.
As the shaft rotates the key extension runs closer to the electronic pick-up
which acts as a switch for the coil. The problem is because the ring is
plastic the key extension can be put into any part of the ring if your not
watching closely. And that is what I did. Larry

Brent I have the same problem with the 318 surging. Did you finally determine what the cause was and how did you fix it.


Doug Wilkins Can anyone tell me where I can find Onan engine parts? I have a John Deere 318 that smokes under acceleration. I'm assuming its rings. It runs great, just smokes pretty bad.
Barry Assuming it is an Onan engine.

I had the same problem and tried everything. I finally figured out that it is related to the fuel pump. The fuel pump is a reed type that works off of crankcase vacuum. The hose from the crankcase appears to fill with oil. All I do it disconnect the hose from the fuel pump, blow into it until it is clear then reconnect. I'm good for a season.

Hope this helps solve your problem.

John Blue I have a john deere 318 that I acquired very cheap,at fist it would not start with the key so I put on a solenoid and whalla it tried to start,after a few tries it was back to jumping the solenoid. After doing that starting business for awhile, I realized it wasn't getting ny gas so I thought I would try gravity feeding the carb and that worked so i figured the fuel pump is bad. But then came my next problem after running the motor for about 5 minutes the battery light came on and it died, not to start again with key ,but with jumping the solenoid. What do you guys think all this could be, the starter nedd rebuilt do to a short and replace the fuel pump?
gary henry nick check your intake and intake gaskets with some carb cleaner lean engines run hot.if you need new ones try the ones we manufacture they seal better than o.e.m.s
gary henry doug you will find one of the few onan aftermarket parts manufacturers at the other end of this e-mail we also cerry oem parts
gary henry doug you will find one of the few onan aftermarket parts manufacturers at the other end of this e-mail we also cerry oem parts
John S I have a similar Onan problem in my John Deere skidsteer. The John Deere 90 uses an Onan. The machine is around 20 years old and has run well up to this point. Inconsistently, it will loose power, sometimes backfire, regain power and loose it again. If it isn't under load, it generally doesn't kill. When it starts to loose power, it gives off some smoke. The smoke does not smell of oil. After reading this site, I cleaned the fuel pump vac.line and found that the oil level was too high and changed the oil. No success. I replaced the fuel filter. No success. Today, I'll try replacing the hoses on the thought that there may be a crack. Any other thoughts?
Rupert Tart I have a 318 jd with onan engine, smoking and have a mechanic to tear it down. He said that I had a broken ring, does it mean that I have to replace pistons with oversized pistons, etc., and do I have to have the block sent off to be rebored?

Gary Henry please send address were I can get
aftermarket parts for onan,and 318 parts

Herman Clark


Gary Henry please send address were I can
aftermarket parts for onan,and 318 parts

Herman Clark

onald sprouse I have a 1987 johndeere onan engine. What types of
oil filters will work other than a john deere oil

Myrle Bought a 1984 318 John Deere with 560 hrs on it. Problem is that it don't run. Removed the head on the left side and when it turns over the piston moves but the valves don't. I AM OPEN FOR SUGGESTIONS. What would you do? Part it out or take it apart, see whats broke, cost to repair, etc.
shawn gleason i have a 16 h.p. onan in my toro. when it has a surge problem i give a little dry gas to her and it clears right out
zane nelson NAPA Gold oil filters work well on my old Onan B43 18hp.
gerald i have a oil leak when it run
Glenn Henry This JD currently will start and run until it is turned off. After it is turned off it will not restart until it is cool to the touch. Ideas on how to resolve?
CliveC Snudden John deere 318 onan engine fuel pump does not pump any gas.?
kkk john deere's Ignition coil is most likely your problem. Coils tend to do that when they start to get hot. If cooled for a while, they will useuly fire back up for abit. I would replace your igition coil.
brandon we have a 318 john deere with an onan engine it will run for a while but it runs out of gas and we have replaced the filter and pump and needle in the carb. when i blow air in the gas tank the filter gets somewhat filled then it will start. Any ideas?
Jerry I am working on a Onan P218G-I/10462A. I am not familiar with this engine. However I am a mechanic. I would like an exploded view of this engine if possible. I am going to replace the points. I don't want to completely tear the engine apart trying to find the points. Thanks
Christopher I'm dealing with this too. I have 1600 hours on my 318 and it is very weak going up hills or when any sort of load is added to it. i checked compression and it is pulling 120 and 118. plugs are fouling, governer is working, air filter is clean, and seems to be getting good fuel.... what's happening??? the spark seems very week on both sides. can this be a problem with the points?
roy stroud I have a 1992 model 318 john deere with an onan engine. What kind of oil do you recommend for this? Thanks.
Richard I have a 1984 318 with the b43 engine, i did an oil and filter change,spark plugs,wires, ciol, points, and condenser and now it doesn't start.The pin that drives the points doesn't seem to opening and closing the point's. this works just like a cam correct? can this pin be worn or did i not put it back in correctly.When i re moved the old set of points this pin was just sitting there, i pulled it out and looked at and then just set it back in and into the sleve on the base that mounts the points.the pin or shaft seems to spin more then go up and down.Have i scewed it up or is it in need of a new pin?
James Lapointe Got 2 questions. I was given a 318 Onan and not sure what oil i should use in this. I only use it during the summer so is Sae30 sufficient enough and what filter to use. Where is the oil release on this tractor as well?
Sam I have 84 318 had it for couple months and it surges like crazy. My Dad and I put a carb kit in it but that made no difference. I have to run it with the choke out to get it to run some what smooth. It's getting to the point I am going to have to take it to some one. I don't know what else to do.
Sam I did forget to add it is a Onan b43.
Franco We have a 318. It has been a very good-running machine, until recently. All of a sudden, the engine would run for 45 sec or so after starting and then quit. The dash lights would go out for 10 sec, and then they would come back on and you could start it again. It started fine but then began quitting earlier and earlier (down to 15 sec) even under no load. My dad and I put in a new fuel filter and cleaned out the carb, but the problem is still there.
Paul G. Hello, I have a 1985 318 with a onan b43g. Problem was the engine would die after running 2-5 minutes. Let it cool down and it would start right up and run again for 2-5 minutes. Problem fixed by removing the ignition points cover unfer the air cleaner, sanding the points cleand and resetting them to .016. Noted also the screw connecting the condenser and the negative primary coil wire to the points was loose. Noted alson this same primary wire was routed under the intake manifold and the insulation was caffed off. Used heat shrink tubing the cover the bare wire. Runs all day now. Nice design , easy to get to the points.
Kari Any ideas as to why our mower won't work in the cold. When put into drive it back fires and kills. It's the 318 model. All new fluids and spark plugs but sill having problems. When we keep in the heated garage it works. Help! We can't afford to keep garage heated just so we can snow blow. Thanks much!
Sean Kari, your problem sounds pretty simple. My 318 was doing the same thing to me too, it just would not start for anything unless it was somewhat warm out. It needs a new set of points and a condensor. the points are located on the front of the engine inside a cover. it takes an allen wrench to take the cover off and the points are right there. the gap setting for them is 21 thousandths. and the condensor is right next to the coil. its silver colored and looks like a double a battery with a wire hooked up to the coil. as soon as you replace those you will certainly notice a night and day difference with how it starts
dave what do i have to do to replace my 1985 p218 onan engine with 1984 b48g engine, or cant it be done? p218 is elect ignition and the b48g has points.
Jerry Watson I have a 1983 John Deere 318 lawn tractor after

I run it for a hour or so the battery light comes

on. It quits charging what could the problem be.

Tony I have a gehl 2500 skidsteer with an onan nhc engine. I have the ignition wired to a toggle switch to shut it off. The problem is that sometimes it will shut off fine, but alot of the time it will actually run better for a while after I flip the switch off and I have to choke it to kill the engine. I'm all ears if anyone has any ideas what it could be.
Brandon I have a 318 john deer its made in the 80's and it dosnt pump any gas and I can blow in the tank and it start but dies I do that several time then it will run great but as soon as it sits for a day or to I have to blow in the tank again
daniel i have a j.d.316 that the p218 broke a rod i replaced it with a b43 it surges like it has no fuel and the filter seemed very low when running so i replaced the fuel lines and the fuel pump and ran a can of sea foam thru the carb by putting the line in the can for a 100% cleaning solution going thru the carb. still surges and even dies ocassionaly when i engage the mower the battery light comes on????? please.any advice is always welcome.
Bill Rice I have a 88 318 with just over 1100 hrs on it.The govrenor needs to be repaired internaly,. I was told the starter should be sent out and be checked, starter rely switch should be put in the seleniod should be checked.Is it worth to spend this much $800-$900 plus new seat and paint(quite a bit of rust). I bought it new in 89 leftover always changed oil & tansmision oil& filter,what is average life for this engine?
jrk I have a johndeere 318 mower it surges at idle and full throttle what is the problem. Please help.
bob marvin i have a 318 john deer with a 218g and have no spark
perry best i'm in need for a good running low hours electronic igniton 318 john deere onan engine.
Ed Preusser I have a John Deere 318 circa 1984 with a Onan 18HP engine. My problem is runs very hot and oil comes up the crankcase vent and gets into the air filter causing lots of smoke. The tractor has been well maintained and has 1035 hours on it. Compression is 95 in both cylinders. Any thoughts ?
George Archers Canada Toronto Bought this maschine--paid $3000 and love to dump it. Case manufactured this machine for 2 years--what a dog. Pure Junk. Never ever would I buy a big machine with a gas motor. Stick with a diesel..The points are located in the front and only 3 inches to work in. Pure Junk--no wonder the ONAN motors are history :^/
Richard I had a surging problem also After trying about everything, I decided to revisit the carb. By bending the float/lever so that the float "closed the needle valve a little tighter, the excessive fuel flow stopped and thus the surging and smoking stopped. It runs like a charm Has about 3500 hours
Bob I solved this problem by drilling out the two part intake manifold and re-sealing it. After drilling out the rivets, separate it with a knife. I found it leaking at the end corner.
Used permetex form a gasket. Then pop riveted it back together. Now it runs like new!

Jim Grant I have a 83 318 and I can not find the oil plug, there is a area under the engine that has a wing nut and what looks like boat plug that you would use to let water out of your hull if it flooded.

dave I have a 318 jd tractor with a 18hp.onans. I rebuilt it 3yrs ago, honned it out and put new rings in it. Now it smokes. What do you think my problem is?
george my battery lite stays on but motor is charging why is this

[ Save This Page ] [ Follow Ups ] [ Post Followup ] [ John Deere Tractors Discussion Forum ] [ FAQ ]
Post a Followup




Email Notification: If you check this box, email will be sent to you whenever someone replies to your message. You must include your email address above to receive this notification.

[ Save This Page ] [ Follow Ups ] [ Post Followup ] [ John Deere Tractors Discussion Forum ] [ FAQ ]


Sign Up For Our Monthly Special Sales!