oil blowing is from a 318 JD incase u were wondering


[ Save This Page ] [ Follow Ups ] [ Post Followup ] [ John Deere Tractor 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
SEARCH MANUALS
FIND PARTS
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:

oil blowing is from a 318 JD incase u were wondering

maria thanks again, M
Dave M - No, it's not normal. You have an oil leak somewhere and the air that is drawn around the engine by the cooling fan at the rear of the engine, is pulling that leaking oil up into the air intake.

Commonly on the 318, it can be the oil sending unit leaking. This is what gave me an oil bath in the air cleaner a few years ago. The sending unit is located next to the oil filter. The seal inside the sending unit fails over time, and results in oil leakage. A new sending unit is only a few dollars from your local Deere dealer. Make sure to use thread sealant on the threads, and don't overtighten the new one. If you do, the seal can crack, and the problem continues.

Of course, it may not be the sending unit, but that's the cheapest thing to try. Otherwise, the oil could be leaking from the rear main seal around the flywheel, or at the oil pan seal. You could take a thin piece of wood, a few feet long, and touch it around the back of the engine around the flywheel, to see if any oil-moist areas exist. That could be an indication of either a rear main seal or the oil pan. Also take a look under the tractor to see if any oil is dripping.

Hope this helps. If it is the rear main seal or oil pan seal, the motor will have to be pulled, and at that time, you'll have to make a decision if it's worth the effort and cost to continue. - Dave

Dave M - Another thought! Depending on how old of a 318 you have, and which Onan engine it has (B43G or P-218G), it could have a bad reed valve (B43G) or the breather tube's filter media could be deteriorated (B43G or P218G).

There are two tubes entering the air filter canister, and my previous post addressed the larger tube coming in from the corner. The above addresses the tube entering more near the center. - Dave

Tim Boisvert Dave is correct in suspecting the reed valve on the Onan motor. Excessive blow-by can also cause this on the "b" series motor. Onan removed the reed valve on the "p" series so the crank case vents directly into the air filter.


Tim Boisvert I read some of your other posts and Alan talks about the blow-by. I had this problem and read some where that the drainback hole for the oil needed to be increased. This was a deere bulletin stating this so I increased the the hole. It may be that this is where the problem is.

How many hours on your motor and can you do a compresssion test? What year is your deere?

Tim Boisvert Got your email, the drain back hole is on the left side, but you need to pull the exhaust and intake manifold and then the cover for the valve tappets. The compression should be over 100, mine is at 90 and 95. You normally don't start blowing blue smoke until the rings get really bad. If your having to add oil between oil changes (no leaks), then the rings are worn. But, the motor will still run for years as long as the oil is kept up.

You might as well check the valve tappet clearance while your in there. I set mine and the compression came up on one of my cylinders from 78 to 90. You can also get an idea of the cam shaft bearing clearance after the valve tappets are set. Mine is over the max by .001

I made an assumption that there wasn't isn't too much oil in the motor



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

Name:
E-Mail:

Subject:

Comments:

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 Tractor Discussion Forum ] [ FAQ ]

Name:
Email:  

Sign Up For Our Monthly Special Sales!