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Fuel leaked in the crankcase

Started by balky1, August 18, 2015, 01:31:20 PM

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balky1

I got an '85 1100 FJ. Recently rebuilt the freakin' petcock. And today I smelt gas while covering the bike. And then I saw the puddle.  :diablo:
Looked at the oil level and it was clear to me that gas leaked into the crankcase. Luckily I always check oil before trying to start it. Total shit. Changed the oil 3k km back.

I now need to change the oil and fix the petcock. Probably float valves in the carbs, too? I mean, since they didn't shut the fuel, one or more are probably broken, right?

In that case what should I consider buying and replacing in the carbs?


FJ 1100, 1985, sold
FJR 1300, 2009

FJ1100mjk

Floats, needles and their seats, and if they are in good to new condition, with the float and float bowl fuel levels set correctly, will not permit the gas to flow from the tank into the engine. Even with a bad petcock that allows fuel to flow if you take the fuel hose of its outlet. <=== This has been established here on this forum, and I can concur with my experiences on my gravity-fed FJs.

One thing I did find that allows too much fuel into the float bowls, is stuck or sticking floats, or small rust/scale particles from the fuel tank's inner surfaces that migrate in the fuel flow, and get caught between the rubber tip of the float needle, and the float needle's seat. Usually some tapping on the float bowls clears this, but it returns again to aggravate until fixed correctly.
Platinum Zircon-encrusted Gold Member

Iron Balls #00002175
www.ironballs.com


Capn Ron

Quote from: balky1 on August 18, 2015, 01:31:20 PM

Looked at the oil level and it was clear to me that gas leaked into the crankcase.


That's called, "Makin' oil!"

I've had fuel tank grit prevent the needles from seating in both a gravity feed '82 Yamaha and on my fuel pump '92 FJ.  In the case of the '82, fuel would continue to flow when the bike was parked and I was makin' oil.  In the case of my '92, fuel would only flow when the bike was running, so it showed up as an overly rich condition and the excess fuel spilling out of the choke circuit tubes.  A good carb and fuel tank cleaning eventually took care of both of those issues, but you have to have a good look at your petcock as well.
Cap'n Ron. . .


There are two types of people in the world...Those who put people into categories...and those who don't.

balky1

Quote from: Capn Ron on August 18, 2015, 02:23:19 PM
Quote from: balky1 on August 18, 2015, 01:31:20 PM

Looked at the oil level and it was clear to me that gas leaked into the crankcase.


That's called, "Makin' oil!"

I've had fuel tank grit prevent the needles from seating in both a gravity feed '82 Yamaha and on my fuel pump '92 FJ.  In the case of the '82, fuel would continue to flow when the bike was parked and I was makin' oil.  In the case of my '92, fuel would only flow when the bike was running, so it showed up as an overly rich condition and the excess fuel spilling out of the choke circuit tubes.  A good carb and fuel tank cleaning eventually took care of both of those issues, but you have to have a good look at your petcock as well.

That stupid petcock. I changed all the O-rings and 4 hole seal. I'm thinking the spring is maybe loose or something from the tank got stuck at that little port where O-ring usually closes the fuel. It's not even leaking, a drip or two from time to time. Once I was lucky when this happened, only overflowed the carbs with nothing in the crankcase, but this time not.


FJ 1100, 1985, sold
FJR 1300, 2009

FJools

IU'm guessing the early FJ's have a gravity/vaccuum fuel feed than the later 1200's with their electric fuel pump?

My 92 is permanently on as I can see it, with just a spanner operated shut off cock for removing the tank. So is there any chance of fuel leaking past the fuel pump into the carbs ?
Still thinking of something..................

balky1

Quote from: FJools on August 19, 2015, 05:49:47 AM
IU'm guessing the early FJ's have a gravity/vaccuum fuel feed than the later 1200's with their electric fuel pump?

My 92 is permanently on as I can see it, with just a spanner operated shut off cock for removing the tank. So is there any chance of fuel leaking past the fuel pump into the carbs ?

Yes, 1100 (maybe early 1200) have vacuum gravity petcock, without fuel pump.

There are definitely 2 things that caused this: faulty petcock that didn't shut off the fuel and float/float valve problem in at least one carb that let the fuel overflow in the crankcase.


FJ 1100, 1985, sold
FJR 1300, 2009

balky1

Just a little update.

I found the reason for petcock leakage. Some mess got stuck in it and it couldn't close properly. Now it's working. The reason for that is the previous owner that cut the screen on the petcock fuel filter so now I don't have the filter at all.
And maybe I panicked too soon. After I moved to bike to a new location, oil level seemed OK. I need to find some level ground to get the proper reading.
I'm still thinking about finding and fixing that one carb that leaked the fuel (i.e. float not working). I was thinking to turn the tap on PRI and see out of which one (or more) the fuel leaks, with engine not running. Do you think that would work? Also a chance to clean the carbs.  :gamer:


FJ 1100, 1985, sold
FJR 1300, 2009

FJmonkey

You need to fix the filter on the petcock first or the problem will continue. This is the root cause and will allow crud and crap to keep contaminating your carbs, regardless how many times you clean them. Like having a leaking pipe, you keep cleaning up the water on the floor but the water comes back...

Then time for a good carb clean, and if your needles and seats are working properly, all will be well again.

Good on finding the root cause, now you are not chasing smoke and gremlins.  :good2:
The glass is not half full, it was engineered with a 2X safety factor.

'86 Ambulance - Bent frame, cracked case, due for an overhaul
'89 Stormy Blue - Suits my Dark Side

balky1

Quote from: FJmonkey on August 20, 2015, 01:25:28 AM
You need to fix the filter on the petcock first or the problem will continue. This is the root cause and will allow crud and crap to keep contaminating your carbs, regardless how many times you clean them. Like having a leaking pipe, you keep cleaning up the water on the floor but the water comes back...

Then time for a good carb clean, and if your needles and seats are working properly, all will be well again.

Good on finding the root cause, now you are not chasing smoke and gremlins.  :good2:

Yeah, but how to fix it when I can't find it anywhere. Except to buy the whole petcock and right now not enough money for such thing. That filter is on my priority list for long time, since I've seen it has been tampered with, but couldn't find it anywhere. In-line filter is out of the question because of starvation probs, as I've read it here.

I was also surprised that without the filter I've still ridden the bike 15000 km witout any problems. That would mean that either the fuel tank and fuel were very clean (lol, not obviously :-D) or that I was one lucky SOB not to get any of the jets clogged.


FJ 1100, 1985, sold
FJR 1300, 2009

FJmonkey

Quote from: balky1 on August 20, 2015, 02:04:16 AM
Yeah, but how to fix it when I can't find it anywhere. Except to buy the whole petcock and right now not enough money for such thing. That filter is on my priority list for long time, since I've seen it has been tampered with, but couldn't find it anywhere. In-line filter is out of the question because of starvation probs, as I've read it here.

I was also surprised that without the filter I've still ridden the bike 15000 km witout any problems. That would mean that either the fuel tank and fuel were very clean (lol, not obviously :-D) or that I was one lucky SOB not to get any of the jets clogged.

I see, a difficult situation to stay running on a budget. Perhaps some other members here can find some options that will help. I will will keep looking, you are not the only one looking for a filter unit to fit an '84/'85.

[edit] I just found something and sent you a PM
The glass is not half full, it was engineered with a 2X safety factor.

'86 Ambulance - Bent frame, cracked case, due for an overhaul
'89 Stormy Blue - Suits my Dark Side

balky1

There is fuel filter manufacturer I found in Croatia. Will see what they say, can they do something.


FJ 1100, 1985, sold
FJR 1300, 2009

Capn Ron

Quote from: balky1 on August 20, 2015, 02:04:16 AM

Yeah, but how to fix it when I can't find it anywhere. Except to buy the whole petcock and right now not enough money for such thing. That filter is on my priority list for long time, since I've seen it has been tampered with, but couldn't find it anywhere. In-line filter is out of the question because of starvation probs, as I've read it here.

I was also surprised that without the filter I've still ridden the bike 15000 km witout any problems. That would mean that either the fuel tank and fuel were very clean (lol, not obviously :-D) or that I was one lucky SOB not to get any of the jets clogged.

Hey Balky...I've been reading through this thread off and on and as is not uncommon with carburetor issues, the topic of filters comes up.  As I mentioned in a previous reply, fine grit in the fuel tanks on two of my bikes gave me trouble.  Now...you own a gravity-feed year and the mere mention of a filter gets everyone all sorts of excited about fuel flow and fuel starvation...so what to do?  Fast-forward to the Monkey mentioning that you HAVE to get the petcock filter replaced and it got me to thinking through this...

Really?  Aren't those petcock filters just just screen-door sized screens to block the big chunks?

I then went to the RPM site to have a look and ....ehhh...they do look like they provide a good amount of initial filtration.  They're tall so they won't get all plugged up and fail and...I'm not sure of the micron size spec, but they're a lot finer than a screen door.  That got me to thinking about your problem in not wanting to buy an expensive petcock juuuust to get the filter.  In-line filters come in all sorts of micron sizes.  My question to you...and to anyone else is...Can't you add an in-line filter that matches the petcock filter in micron size?  Wouldn't that be the same impact on fuel flow as the factory petcock filter?  I imagine it wouldn't be as fine as to completely solve your needle and seat problem, but it would be a barrier to the big chunks of crud coming down the line...
Cap'n Ron. . .


There are two types of people in the world...Those who put people into categories...and those who don't.

balky1

Quote from: Capn Ron on August 20, 2015, 04:58:25 AM
Quote from: balky1 on August 20, 2015, 02:04:16 AM

Yeah, but how to fix it when I can't find it anywhere. Except to buy the whole petcock and right now not enough money for such thing. That filter is on my priority list for long time, since I've seen it has been tampered with, but couldn't find it anywhere. In-line filter is out of the question because of starvation probs, as I've read it here.

I was also surprised that without the filter I've still ridden the bike 15000 km witout any problems. That would mean that either the fuel tank and fuel were very clean (lol, not obviously :-D) or that I was one lucky SOB not to get any of the jets clogged.

Hey Balky...I've been reading through this thread off and on and as is not uncommon with carburetor issues, the topic of filters comes up.  As I mentioned in a previous reply, fine grit in the fuel tanks on two of my bikes gave me trouble.  Now...you own a gravity-feed year and the mere mention of a filter gets everyone all sorts of excited about fuel flow and fuel starvation...so what to do?  Fast-forward to the Monkey mentioning that you HAVE to get the petcock filter replaced and it got me to thinking through this...

Really?  Aren't those petcock filters just just screen-door sized screens to block the big chunks?

I then went to the RPM site to have a look and ....ehhh...they do look like they provide a good amount of initial filtration.  They're tall so they won't get all plugged up and fail and...I'm not sure of the micron size spec, but they're a lot finer than a screen door.  That got me to thinking about your problem in not wanting to buy an expensive petcock juuuust to get the filter.  In-line filters come in all sorts of micron sizes.  My question to you...and to anyone else is...Can't you add an in-line filter that matches the petcock filter in micron size?  Wouldn't that be the same impact on fuel flow as the factory petcock filter?  I imagine it wouldn't be as fine as to completely solve your needle and seat problem, but it would be a barrier to the big chunks of crud coming down the line...


Hi Ron!

Instructed by the current situation that my petcock got clogged and leaked because of that, I would like to have the pre-petcock filter. I found 63 micrometer fabric that I will check for fuel resistance and somehow put on the existing in-tank filter. OEM filter had finer mesh than 63, but that only means I won't starve the bike and won't get such big chunks in the fuel line. That's most important right now. Even before reading the topic on this forum, I thought that in-line filters could cause problems because gravity isn't enough for free fuel flow through much finer paper material filters are usually made of today. But, as you said, coarser filter should, by my logic also, work fine as long it has enough place under the tank for fuel lines not to bend upward at some point, if you get me. That's also, probably, the reason why fuel line routing is very important on these bikes. I am not experienced mechanic, but these things sound logical.
It seems I got lucky and fuel didn't leak into the crankcase. I checked it again seconds ago and oil level looks fine. Although I already ordered new oil, doesn't matter. Some time in the future it will come in handy.  :yahoo:
Also, I don't think debris caused the float to let the fuel leak. This already happened to me once on this bike, probably with the same carb and I haven't dealt it back then. It is either float valve or wrong float setting. I think (read: hope) it is probably the later. Since some job is really pending for me like valve adjustment followed by carb synching (cleaning them before) if I definitely see today that oil level is correct I even won't take the carbs off for cleaning and adjustments since the bike rode fantastic. Then I will go one thing after another some time in the future. Even if it leaks again (and it shouldn't) it's not the problem since I'm the kind of enthusiast that checks the oil level before every start. :good2: And now I will have spare 4 liters.  :lol:


FJ 1100, 1985, sold
FJR 1300, 2009

ribbert

Quote from: balky1 on August 20, 2015, 03:51:05 AM
There is fuel filter manufacturer I found in Croatia. Will see what they say, can they do something.

Balky, in tank screen filters are common on small engine implements, lawn mowers, ride ons etc , cars with in tank pumps have a larger version of the same thing or a filter "bag", depends what will fit through the hole in your tank.
You could even feed a big one in through the filler hole and attach it to the petcock with a hose and just leave it lying in the bottom of the tank.
With the right sort of glue, you could modify one or just use the material and make your own.

Screen fuel grade filters of all sizes are common, I'm sure it wouldn't be hard to graft something on there for primary filtration but it must be made for fuel.

Start thinking along these lines and all sorts of solutions will come to you.

If it was me, I'd start by heading to the local lawn mower shop with the petcock in my hand. Even if they can't help with a part, presumably the bloke now holding it in his hand looking at it has a lot of experience at improvising and might have some ideas or point you in the right direction.

Noel

"Tell a wise man something he doesn't know and he'll thank you, tell a fool something he doesn't know and he'll abuse you"

balky1

Yep, probably.

Thx Noel. All sort of things come to my mind also right now. :-)


FJ 1100, 1985, sold
FJR 1300, 2009