Two days ago the FJ ran fine. I installed a set of heated grips and took a nice ride. Today I went to work, and it quit about a mile form the house.
The bike idles fine, but will not spin up. When it gets to 4000 rpm it sputters out like it's out of gas. Also, sometimes stalls when put in gear.
I checked fuel lines for kinks, nothing. This is an 86, so no fuel pump. If this is gunk in carbs, why would it be so sudden?
I left the bike near a moto shop that happened to be a block away, maybe I'll have them look at it...
Check your petcock to make sure your getting enough fuel for the motor to run properly at higher revs. Frank had a problem like that on our trip out west. Turned out to be a bad petcock... hth
Eric M
Well, I had the shop check it out, since I was a little short on time and didn't want the bike sitting on the street for a couple of days.
They called me back and said I had water in the gas tank.
Quote from: JPaganel on May 06, 2014, 09:11:26 PM
Well, I had the shop check it out, since I was a little short on time and didn't want the bike sitting on the street for a couple of days.
They called me back and said I had water in the gas tank.
So your attempts at a hybrid FJ failed eh? :rofl2: :rofl2: :rofl2: Well then drain the water out and stop the rain dances...
Quote from: FJmonkey on May 06, 2014, 09:26:11 PM
Quote from: JPaganel on May 06, 2014, 09:11:26 PM
Well, I had the shop check it out, since I was a little short on time and didn't want the bike sitting on the street for a couple of days.
They called me back and said I had water in the gas tank.
So your attempts at a hybrid FJ failed eh? :rofl2: :rofl2: :rofl2: Well then drain the water out and stop the rain dances...
"There will be a rain dance this Saturday...weather permitting..." -George Carlin-
Cap'n Ron. . .
Well, I filled up with premium, rode for a day, and got the same thing next day.
I am having some suspicions about this water in gas thing. It runs with choke on, but the symptoms manifest when I push the choke in. Seems to me like some jets might be clogged.
Perhaps it's time to pull carbs and run some spray cleaner through.
Quote from: JPaganel on May 10, 2014, 06:42:10 PM
...... It runs with choke on, but the symptoms manifest when I push the choke in. Seems to me like some jets might be clogged.
Perhaps it's time to pull carbs and run some spray cleaner through.
At the very least take the idle mixture screws, pilots and mains out, then up top, pull the slides and take out the needle jets (aka emulsion tubes) that way you can clean out all the little holes on those tubes....
If things don't get better, be prepared to take the carbs off again and do a more thorough (proper) job.
Well, I found one problem soon as I pulled the tank. The vacuum hose to the fuel valve was hardened and the ends are flared. Entirely possible it was sucking air instead of keeping the gas flowing. Replacing that.
Carbs are pretty clean. #3 and #4 had some rust in the bowls, the emulsion tubes were clean. #2 had some gunk in the tube. #1 I didn't get to yet. Only messed up one screw getting into the carbs, which is pretty dang amazing, given that the screws they used are somewhere between butter and silly putty in hardness.
Quote from: JPaganel on May 11, 2014, 08:48:55 AM
Well, I found one problem soon as I pulled the tank. The vacuum hose to the fuel valve was hardened and the ends are flared. Entirely possible it was sucking air instead of keeping the gas flowing. Replacing that.
Carbs are pretty clean. #3 and #4 had some rust in the bowls, the emulsion tubes were clean. #2 had some gunk in the tube. #1 I didn't get to yet. Only messed up one screw getting into the carbs, which is pretty dang amazing, given that the screws they used are somewhere between butter and silly putty in hardness.
Yes the stock JIS screws are crap. RPM has a nice set that will last http://www.rpmracingca.com/proddetail.asp?prod=carbkit&cat=24 (http://www.rpmracingca.com/proddetail.asp?prod=carbkit&cat=24) also if you have an ACE hardware store in your area they often have metric screws that will work. The nice thing about RPM's kit is you get new o rings. Not bad to have on hand.
I would replace all the vacuum and fuel line hoses if they are originals, 20 -30 years is a long time for rubber hoses.. Also check the condition of the vacuum caps on the intakes.
George
Quote from: movenon on May 11, 2014, 09:33:51 AM
Yes the stock JIS screws are crap.
I've learned to dance this dance on the XJ Hitachis and Mikunis. I have a set of correct JIS screwdrivers, which is what probably plays into this success rate.
Quote from: movenon on May 11, 2014, 09:33:51 AM
RPM has a nice set that will last http://www.rpmracingca.com/proddetail.asp?prod=carbkit&cat=24 (http://www.rpmracingca.com/proddetail.asp?prod=carbkit&cat=24) also if you have an ACE hardware store in your area they often have metric screws that will work. The nice thing about RPM's kit is you get new o rings. Not bad to have on hand.
Shiny. I want to be able to put this together tonight, though. I've had good luck with Ace Hardware and really good luck with Fastenal.
Quote from: movenon on May 11, 2014, 09:33:51 AM
I would replace all the vacuum and fuel line hoses if they are originals, 20 -30 years is a long time for rubber hoses.. Also check the condition of the vacuum caps on the intakes.
Caps are good - I think I replaced them last time I synched carbs.
I'd like to use silicone vac lines. What are they, 3mm?
As to fuel lines... I can't find that hose size anywhere.
Quote from: JPaganel on May 11, 2014, 10:01:53 AM
As to fuel lines... I can't find that hose size anywhere.
I used automotive 3/8" fuel line on my 86'. It should be 10mm, 3/8" is 9.5mm. However, it is not the same outer diameter, it is larger. I heard that you can get 10mm fuel line from Honda with a thinner wall like our OEM lines but I have not verified that. Line routing will be more critical with fatter hoses. Make sure you route properly. Due to the thicker wall tube I also upgraded to screw type hose clamps. The spring clamps will not fit on the fatter hose.
Aaaand... FAIL.
I replaced the vac hose. I finished cleaning up the carbs. #1 had a little crud in the emulsion tube, nothing horrible.
Started perfect, warmed up. Idled great. Crapped at 3K RPM, like clockwork.
I pulled the petcock, filter is clean, inside is clean, when you put vacuum to it, fuel flows. :dash1:
Did you do a blow test to see if all the slides are lifting? Needles installed correctly ?
George
Quote from: movenon on May 11, 2014, 09:22:48 PM
Did you do a blow test to see if all the slides are lifting? Needles installed correctly ?
George
I didn't. Not sure how to do a blow test.
I do know slides move freely, drop down into bores. Needles weren't removed, so I don't see how they would suddenly go from correct to incorrect. Diaphragms look like new.
Also, I did find the drain tube from the filler neck clogged. Poked it with a bicycle spoke and blew it out with compressed air.
See the oval ports ? Blow into each one and the slide should snap up. If you have a leak you will know it. Out of memory if the choke piston's are not seated the diaphragms will also leak. I am on thin ice so please hang in there with me and perhaps someone else can chip in.
(http://fjowners.com/gallery/6/1651_28_11_13_5_59_52.jpeg)
This might not be your problem I am just throwing out shit on the digital campfire. If your needles weren't removed then I guess they are OK. All I know is around 1/4 throttle your needles come into play.
George
Are you sure it's fuel related?
I am not sure of anything Pat ! I gave some thought to electrical but haven't came up with any good ideas that fits his description. There could be a mouse in the air box for all I know. :lol: Any ideas ?
George
Quote from: Pat Conlon on May 11, 2014, 10:50:25 PM
Are you sure it's fuel related?
It feels and sounds like it runs out of gas. Can't be the air - I tried it without the air filter, did the same thing. I suppose it could also be ignition cutting out, but why would it cut out at 3K RPM?
Quote from: movenon on May 11, 2014, 11:15:34 PMThere could be a mouse in the air box for all I know. :lol:
Airbox has been inspected by one of my cats while I was working on this. No mice were reported. :good2:
Quote from: JPaganel on May 11, 2014, 11:21:54 PM
Airbox has been inspected by one of my cats while I was working on this. No mice were reported. :good2:
:rofl2: :rofl2: :rofl2:
Quote from: FJmonkey on May 11, 2014, 11:27:52 PM
Quote from: JPaganel on May 11, 2014, 11:21:54 PM
Airbox has been inspected by one of my cats while I was working on this. No mice were reported. :good2:
You obviously haven't started your bike with the clutch slave off yet, hence the cat still hangs around your bike! Pete. :biggrin:
Quote from: oldktmdude on May 11, 2014, 11:35:17 PM
You obviously haven't started your bike with the clutch slave off yet, hence the cat still hangs around your bike! Pete. :biggrin:
Now that is damn funny dude... :rofl2: :rofl2: :rofl2:
Quote from: JPaganel on May 11, 2014, 09:11:28 PM
Aaaand... FAIL.
Started perfect, warmed up. Idled great. Crapped at 3K RPM, like clockwork.
I like a good puzzle... You say above that the engine quit at 3,000 RPM "like clockwork", but in your original post you mentioned 4,000 RPM. If it's always happening at EXACTLY a specific RPM...and at ANY time (30 seconds after start up...20 minutes after start up...sitting in the driveway...going down the road but ALWAYS at exactly 3k) then I would suspect something other than fuel...such as electrical. grounds, coils, plugs, ignitor, etc... If it sometimes happens at 3k...then at 4k...then at some other RPM, then you're on the right track looking at something less precise in its delivery such as fuel.
It shouldn't be hard to temporarily replace the entire tank. petcock, vacuum switch and fuel lines to the carbs with a bottle full of fuel and a bit of hose. That would split the problem in half anyway..."TO the carbs or FROM the carbs?" If the problem persists (and you're convinced it's fuel delivery issues), then it's time to look at specific carb culprits...
Cap'n Ron. . .
4K was before. 3K was the last time I tried it.
The bike warms up normally. Then, once warm and with choke pushed in, it idles just fine.
I have not completely ruled out electrical. I have just installed heated grips. They are wired into the loose green connector on the right side of the bike that gets power with key on. AFAIK, it's some emissions thing I don't have because it's not a Cali model. and there is nothing else tied into it, it's just switched power. The grips are turned off, so they shouldn't really affect anything, but I'll try pulling the fuse and see if it makes a difference.
I am really not convinced of anything. I am just annoyed and frustrated. This kind of stuff is exactly why carburetors suck. Easier, my foot. :dash1:
I wonder if the guy who wants a rev limiter in the next thread over would want to trade bikes...
:blum1:
Pull a plug or four and see what they tell you, after holding it where it's unhappy.
So, before I continued with all manner of messing around, I decided to get a good baseline. So, I drained not only the carbs, but the tank, as dry as it could get.
Lo and behold, with fresh gas it started and ran. :yahoo:
One hitch was that after cleaning out the dirt in the emulsion tubes the carbs got out of sync. Idle hunted around 2K after warmup. 15 minutes with the trusty sub-$10 sync tool, and idle settled rock solid. Except it was a rock solid 1500 RPM. Dang, that idle screw is a pain to reach... Lowered it to about 900 or so.
Runs great now. Except that really annoying buzz from a crack in the fairing, it's super smooth. Clean carbs are happy carbs. :greeting:
Also, I found some silicone 10mm fuel line on eBay. We'll see how that works out. Mine is still good, but it's starting to develop cracks around the edge.
Quote from: JPaganel on May 14, 2014, 10:38:56 AM
Also, I found some silicone 10mm fuel line on eBay. We'll see how that works out.
Go for it, but you might want to keep in mind that silicone tubing doesn't rate too well for usage with gasoline.
http://www.mcmaster.com/#5034kac/=ryob9k (http://www.mcmaster.com/#5034kac/=ryob9k)
Fluorosilicone tubing is better.
Quote from: FJ1100mjk on May 14, 2014, 11:01:42 AM
Go for it, but you might want to keep in mind that silicone tubing doesn't rate too well for usage with gasoline.
http://www.mcmaster.com/#5034kac/=ryob9k (http://www.mcmaster.com/#5034kac/=ryob9k)
Fluorosilicone tubing is better.
The stuff I ordered is not "high purity white silicone", but I can take a piece of it, stick it in jar of gasoline for a while and see what happens.
Quote from: JPaganel on May 14, 2014, 12:25:15 PM
The stuff I ordered is not "high purity white silicone", but I can take a piece of it, stick it in jar of gasoline for a while and see what happens.
Some more information on its compatibility...
Select silicone as the material, gas (unleaded, or leaded) for the chemical, see rating.
http://www.coleparmer.com/Chemical-Resistance (http://www.coleparmer.com/Chemical-Resistance)
Report back with your test results. I'm interested.