1986 FJ1200 Spews Oil from Crankcase Breather Hose

[joshuadaymon]

After Engine is warm, and Ive been riding for say 15-20 mins im soaked in oil. I though new air filter + oil filter and viola! (tightened oil filler cap) But no such luck happened again to me yesterday got PO"ED and left the bike where it stood. Bad choice... as i lost my keys at the bar soon after. (Getting more made ASAP spare being mailed to me). So.. it runs great no problems until this. Thought maybe it was a stuck float and filling with gasoline... so i drained the rest of the oil maybe 1/2 a quart and it didn't smell like gas. If there was away to get a "lock" off so i could bring it into a smith i would if anyone can elaborate how to do this easily. But any ideas what could be wrong i asked the folks at the cycle shop they said check for a stuck float.... Didn't smell gas. As soon as i get they key (if its even coming) or get one made ill check compression but trying to deduce what could be wrong from this point. Any input would be appreciated.

[FJmonkey]

Seems to be over filled with oil. Check with engine hot, on center stand, level ground, engine off.

[Pat Conlon]

 It could be just the blow by from your rings. How many miles on the engine?
Our old air cooled motors run looser tolerances, compared to today's modern water cooled engines.
Before the rebuild, I also had that problem with my high mileage (135k) motor when I installed Unipods and the crank case filter.
What was happening was that the 3" long hose I had between the crankcase vent port, and the filter was too short in length.
A longer hose (~14") stopped the oil from getting to the vent filter.

Of course this longer hose did not stop the blow by, but it sure cut down the amount of oil reaching the crankcase vent filter.

Hope this helps. Report back and let us know what you find out.

[Alf]

Extracted from the workshop manual: Yamaha says that it is the secondary oil circuit, helping valve steam O rings lubrication. So you can avoid the oil going to your breather hose, and more if the crank is overfilled

[Dan Filetti]

I was thinking too much oil as well. This same thing happened to me when I accidentally overfilled the fj with oil  one time.

One thing in addition to what Pat said, make sure the bike is level, (as in on the center stand) on level ground with the engine warm...

Dan

[FJmonkey]

One thing in addition to what Pat said, make sure the bike is level, (as in on the center stand) on level ground with the engine warm...
Dan

Pat, does this make you a Monkey's Uncle??? Or a Power Ranger wana-be???

[joshuadaymon]

180k miles

oil was filled correctly center stand warm.

doing pressure test tomorrow.

[joshuadaymon]

pressure test turned out positive

[Pat Conlon]

Please explain what you mean. Are you talking about a compression test, or a leak down test, or.....?

[FJmonkey]

pressure test turned out positive

With a pregnancy test "Positive" means you are Pregnant, does this pressure test result of "Positive" mean you have pressure?

Like Pat said, what test did you perform and what readings did you get. This group has some ace FJ mechanics and can tell a lot from the specific results of diagnostic tests. The more you can tell us the more we can help you fix your FJ issues.

And when you have the time consider an introduction of your self to the group. This group is much more like a campfire with all of us hanging out and shooting the shit. We have annual rally's and when not riding the best roads we can find we hang around the campfire. It is nice to know more about the new members that join and what motivated you own an FJ.

[joshuadaymon]

full throttle did a pressure and leak down test, said it was fine

[FJmonkey]

I got nothing... What were the pressures from each cylinder for each test? Give us quality info and we can respond in kind. Is this your fist bike?

[joshuadaymon]

not my first bike, sorry about the info being vague, my wife brought it to full throttle and they tested pressure and leakdown and said it came back as the bike was fine.
i just did a pressure test myself and i get 160 per cylinder ish, if i hold starter down awile seems to incease a little but roughly 150-160 on all.

[joshuadaymon]

after looking at some stuff online im wonding if the sidecasing is original... so oil meter may be off but after dropping oil+filter i was putting the right cc's according to manuel, i think ill put it in my truck and just have yamaha country figure it out. too much headache

[fj11.5]

can you put up a pic to show us