91 Fatboy spitting oil

[Little Al]

I'm helping out a buddy, 1991 Fatboy. Hasn't run in about 12 years. Changed plugs, oil, oil filter, air cleaner, primary and trans oil. New battery and fresh gas. fires right up but there's a vent from crankcase to air cleaner backing plate that spits oil, a lot of oil. If I take the cap off the oil tank it stops spitting. I vaguely remember something about a flap valve or something in the rocker box that sticks if the motor sits for a long time. Or maybe I'm off MY rocker, lol.

The motor is completely stock and it's the original owner so we know that for sure and the bike was running perfectly with no issues when he put it in storage.

advice? fix?

thanks in advance,
Little Al

[thumper 823]

Mine is a 1994 and it is vented ti the atmosophere as in just like old school.

Maybe they thought they were improving  it moving it up the the air filter?

[Little Al]

got ya Thumper but it's really spitting a LOT of oil and that can't be normal, lol
I believe the move to venting into the ac was supposed to prevent pollution, LOL

[jsachs1]

Sounds like the ball in the low tower(inner most)part of the oil pump isn't seating. Remove cap on tower, remove spring, remove ball. Check the seat the ball rests on. May need to lap that seat.
John

[Little Al]

 jsachs1, could you explain that in more detail please

[MikeL]

How much oil did you get out of the oil tank? With 12 yrs sitting some of the oil migrated to the sump. So you added 4 qts on top of ?? oil that migrated to the sump/crankcase. You are most likely over full and this will cause oil to spit or really spit/puke out of the breather. 1991 was case vent with a pipe to the air cleaner.
What I would do is remove the pipe to air cleaner and direct the oil flow to a pan with at least a gallon capacity and run the engine till the oil stops.Then check the level in the oil tank.

                                                                                                                                                                   MIKE

[JW113]

1. Remove the breather line at the air cleaner, point it into a bucket.
2. Fire up the motor and run it until it stops blowing oil.
3. Pull the plug in the oil drain line from the tank, completely drain the oil.
4. Leave the plug out with the oil pan still under the hose.
6. Fire the bike up, let it idle and watch the oil pressure light.
7. As soon as the oil pressure light comes on, shut it down.
8. After the drain hose quits dripping, put the plug back in and fill tank with -> 2 <- quarts of oil.
9. Fire the motor up, let run for a bit, see if it stops blowing oil out the breather.

By the way, venting the crankcase to the air cleaner is an EPA requirement, just like every car & truck sold since what, 1967?

-JW

[Scootrskum]

JW, is this an alternative to pulling the return line going to the tank to completely flush the old oil out?

4. Leave the plug out with the oil pan still under the hose.
6. Fire the bike up, let it idle and watch the oil pressure light.
7. As soon as the oil pressure light comes on, shut it down.

[JW113]

I did not say to pull any of the oil lines. The only two hoses to mess with are the oil tank drain line (the one that hangs down from the tank behind the transmission and has a metal plug you use to drain the tank), and the hose that connects to the air cleaner.

It sounds like you have two problems. The bike has wet-sumped, and you have too much oil in the tank/engine. What I am suggesting is to completely purge the engine of oil, and start from ground zero. THEN figure out if you have a chronic wet-sumping issue. As was already stated above, there is a check ball in the oil pump to control wet-sumping. If it gets any gunk, sludge, whatever on it, it will leak. But first, figure out if you really have a problem or not.

Oh, and if you don't have the factory shop manual, get one. This is well documented in it.

-JW

[Scootrskum]

JW, I'm not the one with the puking oil issue. I know you didn't say pull any oil lines and to just pull the plug on the drain line. I was just wondering if running the engine with the drain line unplugged would purge all the oil out of the sump so I could get all the old nasty stuff completely out of the motor? You basicaly answered my question in your relpy though. Much appreciated.   

[04rkryder]

The method JW gave is great for purging the oil system, but if you're worried about mixing old oil with new, then the Rogue Chopper Scavenger might be a better idea. Change oil as normal(drain oil tank and add fresh oil, but before putting the new oil filter on, put the Scavenger puke on and run motor till the oil coming out of the puke is clean. Remove puke and install oil filter, top off oil tank. Never worry about running engine out of oil.

[Dan89flstc]

The method JW gave is great for purging the oil system, but if you're worried about mixing old oil with new, then the Rogue Chopper Scavenger 

Just follow JW`s method, no need to spend money on a gadget.

[04rkryder]

The method JW gave is great for purging the oil system, but if you're worried about mixing old oil with new, then the Rogue Chopper Scavenger 

Just follow JW`s method, no need to spend money on a gadget.

Never said to buy the Rogue Scavenger, only it might be a better idea. Most spent a lot of money on chrome and other "GADGETS" that don't get you home, but then cheap out on oil etc. that will get you home. I personally won't bet on a 25 year old(in my case) switch that might stick open for a few seconds and run my engine out of oil.
To each his own. 

[Little Al]

thanks so much JW and the rest of you guys.
I think JW's solution actually addresses the problem, too much oil leaked down over the years into the crankcase.
I shoulda thought of that since I only drained about 2 quarts when I changed the oil. I'll let you know how it works out.

Thanks again,
Little Al

[thumper 823]

Wrong valve covers?
breather gear is plastic,  out of time, and or  broke ?

[Dan89flstc]

Wrong valve covers?
breather gear is plastic,  out of time, and or  broke ?

Nothing broken, out of time etc...The bike has been inactive for years.

Any HD with an oil tank mounted higher than the engine will do this if it sits for years....

[david lee]

thanks so much JW and the rest of you guys.
I think JW's solution actually addresses the problem, too much oil leaked down over the years into the crankcase.
I shoulda thought of that since I only drained about 2 quarts when I changed the oil. I'll let you know how it works out.

Thanks again,
Little Al

jw has good advice

[Little Al]

gonna be back at the bike wednesday or thursday of this week.
Will follow JW's advice and let you all know the results but I'm expecting it to solve the issue.

Thanks all again

[thumper 823]

If the plastic gear is still in there it most definitely could be broke, warped, grooved, spindelated.