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General Category => Yamaha FJ1100 / FJ1200 Running Problems => Topic started by: Cash Dereszynski on March 30, 2015, 06:29:35 PM

Title: carb sync
Post by: Cash Dereszynski on March 30, 2015, 06:29:35 PM
Carbs out of sync? Hose routing:vent, overflow. Wish I could attach a video / audio clip.
What are the symptoms.

Cash
Title: Re: carb sync
Post by: FJmonkey on March 30, 2015, 06:56:36 PM
Cash, I am not sure what the problem is based on the post. I have a manometer for balancing carbs, all we need is some time off for me to bring it along and sync your carbs. This way the sync can be ruled out of any running problems.
Title: Re: carb sync
Post by: Urban_Legend on March 30, 2015, 08:08:33 PM
Some of the symptoms of carbs out of sync are - running rough, popping and back firing,  and generally running like shit. These are also symptoms of air leaks, bad plugs , bad fuel and probably half a dozen other things. But doing a sync is a good place to start, and while you have the tank off you can check the others things.
Title: Re: carb sync
Post by: Cash Dereszynski on March 30, 2015, 08:12:27 PM
Dude

I texted you a clip. I have this, need my aux gas tank. Try again.  :dash2:

Cash
Title: Re: carb sync
Post by: Arnie on March 30, 2015, 08:49:04 PM
Cash,

I have the same set of cheap vac guages, and have had them for years. (paid $15 from JC Whitney)
Make sure you sync the guages BEFORE you use them to set your carbs.
You can do this fairly easily by connecting all 4 to a manifold (or 3 T fittings) and apply a constant vacuum.
See if all the needles point to the same number.

IF NOT (likely) you'll have to put a label on each gauge face to indicate a "common" point so you can set your carbs accurately.

Note: I've 'retired' my set of gauges and now use a different sync device.
Title: Re: carb sync
Post by: FJmonkey on March 30, 2015, 10:37:18 PM
Quote
Dude

I texted you a clip. I have this, need my aux gas tank. Try again.  :dash2:

Cash


Here is my Aux tank...
(http://fjowners.com/gallery/8/104_30_03_15_9_27_22.jpeg)

My first attempt to view the vid had no sound... Now I can hear it... No clue, could be many issues. Need to rule out each one till nothing is left and the bike runs well.... So many variables in a bike that was essentially a basket case. Pods, clearly an open pipe. What was done to the carbs to open up the flow?

If you can sync them then that is not the problem. Check that box off for now and move on to the next possible issue. Have you checked the plugs, rich, lean?
Title: Re: carb sync
Post by: movenon on March 30, 2015, 11:43:36 PM
Mark now with your new and improved ride with a fuel pump you can just use a 1 gallon plastic gas container and just dip your fuel line hose into it. Sits nicely on top the battery box. Live on the edge...
George
Title: Re: carb sync
Post by: X-Ray on April 01, 2015, 05:43:47 AM
I was a bit lazy and just ordered one of these tanks http://www.ebay.com.au/itm/161231728531?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com.au/itm/161231728531?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

Still want to get the carb sync tool and compression tester though.
Title: Re: carb sync
Post by: Cash Dereszynski on April 02, 2015, 05:40:30 PM
uncalibrated first attempt. Calibration is the key, thanks for the insight.

Cash
Title: Re: carb sync
Post by: Cash Dereszynski on April 03, 2015, 11:44:14 PM
Because the way I'm suppling gas (under pressure) with a sprayer, the idle is inconsistant the gauges are useless and the sync adjustment screws seemingly do nothing. I'm concidering other solutions . Preferably plug and play. RPM full set. Who's done that? Can you ship the old carbs and have them redone to specification(headers/pod filters).
Or just a box with the answer inside,brand new carbs is the way to go? javascript:void(0);

Regards

Cash 
Title: Re: carb sync
Post by: movenon on April 04, 2015, 12:01:18 AM
Speaking out of turn here but YES RPM can rebuild / set / bench adjust your carbs.  Send him an e mail from his site.  But I don't get why. Set up a gravity feed and sync. your carbs ?

Balance 1 & 2    then balance 3 & 4     Then with the center screw balance 1&2 to 3&4  Then repeat to fine tune.

George
Title: Re: carb sync
Post by: Bones on April 04, 2015, 02:06:22 AM
Why use a pressure sprayer?? that would be applying heaps more pressure than even a fuel pump could supply and causing all sorts of problems. these things aren't fuel injected so you dont need any pressure for it to run. In fact you don't even need an aux tank to sync carbs, the fuel hose should be long enough to just pull the tank back, turn it 180 deg and sit it on the subframe, there's heaps of room that way to get at the screws and adjust.
Title: Re: carb sync
Post by: copper on April 04, 2015, 11:23:47 AM
Quote from: Cash Dereszynski on April 03, 2015, 11:44:14 PM
Preferably plug and play. RPM full set. Who's done that? Can you ship the old carbs and have them redone to specification(headers/pod filters).
Cash  

Randy has done my set twice over the years and I have been very happy both times. From the first time I removed the air box and against Randy's recommendation used K&N air filters because I had heard some many great things about them.

Well, forward about 2 years after the rebuild and I let the bike sit for a year and did not treat the fuel and they got all gummed up, so off to Randy again. Much to my disappointment he showed me pictures of my carbs and how bad the fitlers were and one after they were cleaned.

So, the second time I bought the RPM pod filters and have never looked back as just like is mentioned here a lot, I treat my fuel now with stabilzers to keep them from gumming up.

There have been a couple of carb rebuilds recently that other members have reported on that I remember.
http://www.fjowners.com/index.php?topic=13222.msg132942#msg132942 (http://www.fjowners.com/index.php?topic=13222.msg132942#msg132942)
http://www.fjowners.com/index.php?topic=13317.msg133993#msg133993 (http://www.fjowners.com/index.php?topic=13317.msg133993#msg133993)
http://www.fjowners.com/index.php?topic=10053.0 (http://www.fjowners.com/index.php?topic=10053.0)

I think if you send him your carbs, you will not be disappointed with the results, I know myself and others have been happier than expected with the results.
Title: Re: carb sync
Post by: Cash Dereszynski on April 04, 2015, 06:33:46 PM
Quote from: Bones on April 04, 2015, 02:06:22 AM
Why use a pressure sprayer?? that would be applying heaps more pressure than even a fuel pump could supply and causing all sorts of problems. these things aren't fuel injected so you dont need any pressure for it to run. In fact you don't even need an aux tank to sync carbs, the fuel hose should be long enough to just pull the tank back, turn it 180 deg and sit it on the subframe, there's heaps of room that way to get at the screws and adjust.
Good tip thanks

Cash
Title: Re: carb sync
Post by: Cash Dereszynski on April 04, 2015, 06:40:07 PM
Synced the carbs (with Help of Dr FJmoney) runs better soothed out. Adjusted air screws per dynojet 5 turns out, as it is. Still seams restricted under load. So next is needle adjustment. Or.....?

Cash
Title: Re: carb sync
Post by: movenon on April 05, 2015, 08:45:42 AM
If you are 5 turns out on the fuel/air screws then I would suggest your pilot jets are either to lean or dirty. You should be closer to 2 to 3 turns out.  Not a fan of DynoJet but they will work.  The fuel/air screws and pilot jets effect your throttle opening mostly from 0 to 1/4 throttle.
George
Title: Re: carb sync
Post by: Mark Olson on April 05, 2015, 04:33:27 PM
Quote from: movenon on April 05, 2015, 08:45:42 AM
If you are 5 turns out on the fuel/air screws then I would suggest your pilot jets are either to lean or dirty. You should be closer to 2 to 3 turns out.  Not a fan of DynoJet but they will work.  The fuel/air screws and pilot jets effect your throttle opening mostly from 0 to 1/4 throttle.
George

Yeah , what George Said... 5 turns way too much. you need new pilot jets. (bigger)
Title: Re: carb sync
Post by: Cash Dereszynski on April 06, 2015, 12:38:38 AM
Could it be float bowl height?

Cash
Title: Re: carb sync
Post by: movenon on April 06, 2015, 01:16:38 AM
Shooting in the dark here.  Your floats should be set at 22mm.  http://www.fjowners.com/index.php?topic=9560.0 (http://www.fjowners.com/index.php?topic=9560.0)  scroll down to the fifth post. Your pilot jets need to CLEAN.  And probably larger if you are 5 turns out.  Most of the FJ's that upgrade go to 40 or 42.5 Mikuni pilots.  Be aware that "DynoJet" jet numbers are not the same as Mikuni's. That's one of the reasons I don't like DynoJet conversions. I know , I had one...
George



Title: Re: carb sync
Post by: FJmonkey on April 06, 2015, 09:23:35 AM
Once we got the carbs synced it idled well. There was an occasional pop coming from carb #1, I could see it on the manometer when it happened. I did not ride it so I can't help on throttle response at different positions.
Title: Re: carb sync
Post by: Cash Dereszynski on April 07, 2015, 03:18:10 PM
Picture of plug before raising needle.

Cash
Title: Re: carb sync
Post by: Cash Dereszynski on April 08, 2015, 10:51:21 AM
Seafoam worked for me . Now the FJ feels like it should
A beast.

Cash
Title: Re: carb sync
Post by: Cash Dereszynski on April 08, 2015, 11:40:19 PM
It's still lean. 20 miles in town . With seafoam additive.

Cash
Title: Re: carb sync
Post by: Cash Dereszynski on April 20, 2015, 06:20:30 PM
On the advice of dynajet I've moved the needles up two notches. At times it runs at all throttle settings smoothly . Alternitely hesitating and popping other times .Also it's very cold blooded and warm up is two cigarettes . The symptom of surging and popping seems like fuel starvation so I'm suspecting the vacuum petcock maybe another possible source of the problems. I'm riding it but not too far from the home base. Got to Malibu turned back after it seems to be running out of gas, but by the time I got home it was strong again at all settings . WTF ? More riding to test what is really happening.

Pix is a gutter in Malibu FJ idleing for 10 minutes.

Cheers,

Cash
Title: Re: carb sync
Post by: FJmonkey on April 20, 2015, 06:28:15 PM
Cash, do the suck test on the vacuum line. leave it on the petcock, when you draw vacuum it should give a little then you should feel like the tube is plugged. If you can keep sucking air, then the hose or petcock is failing/failed. I had intermittent fuel feed issues on my '86 till I discovered the petcock was on its last legs.
Title: Re: carb sync
Post by: Pat Conlon on April 20, 2015, 06:47:35 PM
I hope you were kidding about your FJ idling for 10 minutes.

You think you have problems now....wait until you cook those exhaust valves.

Stop what you are doing. Take your carbs off. Drain the gas. Box them up and send them to RPM.
Title: Re: carb sync
Post by: Cash Dereszynski on April 20, 2015, 07:51:39 PM
Quote from: Pat Conlon on April 20, 2015, 06:47:35 PM
I hope you were kidding about your FJ idling for 10 minutes.

You think you have problems now....wait until you cook those exhaust valves.

Stop what you are doing. Take your carbs off. Drain the gas. Box them up and send them to RPM.
That may be the next step. I've been Talking to RPM,I'd take them off,box um, and Ride there on my Beemer.

Cash
Title: Re: carb sync
Post by: Cash Dereszynski on April 20, 2015, 07:53:06 PM
Quote from: FJmonkey on April 20, 2015, 06:28:15 PM
Cash, do the suck test on the vacuum line. leave it on the petcock, when you draw vacuum it should give a little then you should feel like the tube is plugged. If you can keep sucking air, then the hose or petcock is failing/failed. I had intermittent fuel feed issues on my '86 till I discovered the petcock was on its last legs.
I'll try that.

Thnx

Cash
Title: Re: carb sync
Post by: Mark Olson on April 21, 2015, 02:34:22 AM
how is the gas cap vent? I see a magnetic tank bag in the pic ... they are known to cause a vacuum lock and starve carbs.
Title: Re: carb sync
Post by: Cash Dereszynski on April 21, 2015, 09:19:07 PM
Quote from: Mark Olson on April 21, 2015, 02:34:22 AM
how is the gas cap vent? I see a magnetic tank bag in the pic ... they are known to cause a vacuum lock and starve carbs.
I never heard that one before.

Cash
Title: Re: carb sync
Post by: Mark Olson on April 22, 2015, 03:09:55 AM
Quote from: Cash Dereszynski on April 21, 2015, 09:19:07 PM
Quote from: Mark Olson on April 21, 2015, 02:34:22 AM
how is the gas cap vent? I see a magnetic tank bag in the pic ... they are known to cause a vacuum lock and starve carbs.
I never heard that one before.

Cash

The early model gravity fuel feed fj,s have this problem..It can be corrected by removing the flapper valve inside the gas cap..then you can still use magnetic tank bag without further problems. If you suspect this happening ,try riding with gas cap open and see if problem goes away..
Title: Re: carb sync
Post by: Cash Dereszynski on April 24, 2015, 04:37:05 PM
WTF.
Adjusted needles irratic running , pulled it apart will check tank vents and petcock again . Going to check Float bowl height. Getting to th point of a ride to RPM....
Pix Left to right.

Cash
Title: Re: carb sync
Post by: simi_ed on April 24, 2015, 04:42:40 PM
Pilot jets!  Clean them again.
Title: Re: carb sync
Post by: Cash Dereszynski on April 26, 2015, 09:31:30 PM
Pulled the carbs checked the float level all at 22mm, all ports clear. reassembled and now I wait for a new vacuum petcock. It's got to be the petcock!

Cash