FJowners.com

General Category => Yamaha FJ1100 / FJ1200 Running Problems => Topic started by: Mike324 on September 13, 2020, 06:01:34 AM



Title: Air Lock and Idle Question on 86
Post by: Mike324 on September 13, 2020, 06:01:34 AM
Hello fellow owners,
Finally got my new RPM petcock installed and the bike insured and plated. Have been only starting the bike and riding in driveway since I bought it last fall. I was expecting it to run a bit rough, but it ran great. I rode it for half and hour slowly getting used to riding position etc., gassed up, and drove another half hour on some country roads. Pure joy! When parked at home I could hear the whistling sound from the tank that is familiar to many.

The next day I promised my wife a good coffee and took her for a slow ride, 3,000 - 4,000 rpm max. As we got close to the cafe destination, only ten minutes from home, the bike began sputtering and then came to a stop as if running out of gas. Fuel read almost full. I tried reserve position just in case I had a petcock problem and no luck. I then opened up the gas cap, as I have had to do on my 80 Gold Wing several times before, and the FJ started right up and within two minutes was running great again. Did I experience an air lock? I have looked on the forum for solutions to the gas cap venting problem. Seems the seal may need replacing or removal if I am reading correctly?
Thanks for any suggestions, Mike



Title: Re: Air Lock and Idle Question on 86
Post by: Waiex191 on September 13, 2020, 09:46:58 AM
Mike,
My '89 has a vent line that comes from a fitting at the back of the tank. Is yours pinched or anything?  Or does the '86 not have that setup?


Title: Re: Air Lock and Idle Question on 86
Post by: Pat Conlon on September 13, 2020, 10:53:56 AM
Bryan, that fitting at the back of the tank is a drain line for any fluid that builds up in your recessed gas cap. All 1986-1995 FJs with the recessed gas caps have this drain.

Mike, is your fuel line routed correctly?  http://www.fjowners.com/index.php?topic=18286.0 (http://www.fjowners.com/index.php?topic=18286.0)


Title: Re: Air Lock and Idle Question on 86
Post by: Mike324 on September 13, 2020, 03:30:26 PM
Thank you for your responses. Yes I was quite careful when installing the new petcock to make sure the lines were in the right place. I did have a look at that link before. I will check again to make sure. Is the whistling sound something that needs to be corrected or can it be left I wonder?

The idle question can wait until I have more time in the saddle. It just seemed a bit fast when I got home...1500.

Thanks, Mike


Title: Re: Air Lock and Idle Question on 86
Post by: Pat Conlon on September 13, 2020, 07:27:57 PM
Mike, do you have a Calif. model FJ?
When folks alter the vapor control system on the Calif. models, strange things happen to the fuel tank venting.

FYI Here are some pictures showing the cap assembly and the flapper valves we take out for venting.

http://www.fjowners.com/index.php?topic=2024.0 (http://www.fjowners.com/index.php?topic=2024.0)

Hint: When you take the cap apart do it in your bathtub bucket. The drain is the first place the ball will go.... [edit by the Monkey] ....you crazy monkey, you don’t leave the drain open [edit by Pat]
Why?
There is a tiny steel ball (the key flap detent ball) that is under spring pressure and when you pull the cap apart, that little bastard flies out with amazing velocity, always in a unknown direction...ending up captured by some kind of rift in the space/time continuum.

If you search thru the forum with the term “Flapectomy” you will find many posts from folks who have had the same thing happen to them as you did with the bike stalling.

Re: Idle. 1) Adjust valves, then 2) Sync the carbs....then work on your final tune.
Here is a good write up from Factory Pro to review. Look at Section 4

http://www.factorypro.com/tech_tuning_procedures/tuning_carbtune,CV,high_rpm_engines.html (http://www.factorypro.com/tech_tuning_procedures/tuning_carbtune,CV,high_rpm_engines.html)


Cheers


Title: Re: Air Lock and Idle Question on 86
Post by: Mike324 on September 14, 2020, 04:56:04 PM
Thanks Pat for links. I will read them with interest. I have what I believe is the Canadian import. It was sold new in Canada and has the Lateral not Perimeter term in script. Really enjoyed my first two rides this past weekend, with the exception of that brief sideline. Love the riding position and seat, not to mention the fabulous torque! Mike


Title: Re: Air Lock and Idle Question on 86
Post by: Pat Conlon on September 14, 2020, 05:55:13 PM
Kookaloo!