Up and died.

[JPaganel]

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...

[Yamifj1200]

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

[JPaganel]

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.

[FJmonkey]

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?  Well then drain the water out and stop the rain dances...

[Capn Ron]

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?  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. . .

[JPaganel]

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.

[Pat Conlon]

...... 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.

[JPaganel]

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.

[movenon]

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 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

[JPaganel]

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.

RPM has a nice set that will last 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.

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.

[FJmonkey]

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.

[JPaganel]

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.   

[movenon]

Did you do a blow test to see if all the slides are lifting?  Needles installed correctly ?
George

[JPaganel]

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.

[movenon]

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.



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