Any help would be appreciated before I throw a match on my 86 Venture....

[Javenmcd]

Well...here's your daily update. Pulled the carbs and re-re-reverified float levels. Pulled the jet block rubber plugs and gave them a wintergreen/alcohol refresh bath. Reinstalled everything and.....same results. As the bike sits from being warm, the carb vents leak fuel. Fuel pump cycles but it does start as I guess it's not being restricted by all the crap I've removed from the system (emissions stuff, tank vent)

 

Here's my next theory so let me know your input please: As the bike sits and cools its obviously letting fuel in (and back out thru the vents). When the carbs are inverted and off the bike you can blow into the inlet and air doesn't get by but it MUST be allowing fuel by. The only thing I can figure is that the K&L needles and seats aren't compatible with the bike and I need genuine Yamaha stuff. Maybe the fuel is even getting in AROUND the seat. The seats did have an o ring but they weren't very hard to press into place. Yay I get to pull the carbs for a 5th time!!! Anyone have any thoughts here?

Edited March 12, 2017 by Javenmcd

[snyper316]

Well...here's your daily update. Pulled the carbs and re-re-reverified float levels. Pulled the jet block rubber plugs and gave them a wintergreen/alcohol refresh bath. Reinstalled everything and.....same results. As the bike sits from being warm, the carb vents leak fuel. Fuel pump cycles but it does start as I guess it's not being restricted by all the crap I've removed from the system (emissions stuff, tank vent)

 

Here's my next theory so let me know your input please: As the bike sits and cools its obviously letting fuel in (and back out thru the vents). When the carbs are inverted and off the bike you can blow into the inlet and air doesn't get by but it MUST be allowing fuel by. The only thing I can figure is that the K&L needles and seats aren't compatible with the bike and I need genuine Yamaha stuff. Maybe the fuel is even getting in AROUND the seat. The seats did have an o ring but they weren't very hard to press into place. Yay I get to pull the carbs for a 5th time!!! Anyone have any thoughts here?

 

It depends which kit you got, If you got the same one as I got yes it should work with your 86 venture..... XVZ1300 Venture 18-2879

[Javenmcd]

That's the one....we'll crap. Not sure where that leaves me now.

[CaseyJ955]

Genuine Yamaha is obviously excellent but spendy. Of the aftermarket I have read that the Japanese made K&L is the only route to go, anything else is a crap shoot and probably made in China. I know the guys on the Vmax side have had good luck with K&L but not others.

 

When I did my jet block plugs I had to soak them for 2 days before they started to soften up and take their normal shape but they were rock hard and distorted when I began. After a 2 day soak I could feel they were softer and had taken their normal shape, had to wiggle them back in and they were quite snug. You did use 100% wintergreen oil with the alcohol? I believe it was cimmer (I think) that iterated how important the jet block plugs are in the other thread.

 

Since the bike is together may I suggest a wet float level test. If the fuel level is maintaining it's proper level then I think we can rule out floats/needles/seats and move on to other possibilities. Hoping we can narrow the problem down by ruling things out. I'll attach a page on the wet float level check. We'll get to the bottom of this. I assume the air box was installed during the tests, these carbs wont behave well at all w/o the air box installed.

 

I know there are some guys here that have been doing this longer than I have so there is a better way please step in and correct me.Wet Float Measurement (1).pdf

[cimmer]

One thing comes to mind and just want to check with you... The needle valve for the fuel inlet has a wire attach to it that has a cut in the wire. Are you fitting the float tab into the cut of the wire. That is how it is suppose to go. I have included a photo of the Keyster Carb kit, K-1359YK. It is available on ebay or I ordered mine from http://www.siriusconinc.com. They also have a set of rubber plugs for the bottoms of the jet block for under $20 for all 8. I did order these also but I have tried them to see how they fit but I did just disassemble a carb tonight and can try them tomorrow for you and let you know. It is strange that the carbs are not venting out the tubes on top of the float bowl covers. I take it you can blow air thru those tubes as well.

Sorry for some of the basic questions but just mentioning everything. Have you check to see if maybe you have a bad float. Setting the float height when dry is on thing but what about when they are wet. Before you disassemble the carbs again, do the wet float check on them with some clear tubing. The procedure is listed in the service manual and might be worth the time to do it. Least it let you know if the floats are good or if maybe one is sinking a bit and letting too much gas in.

Let us know what you find and good luck.

Rick F.

[BlueSky]

I used K&L needles and seats in my Kawasaki carbs and they did great. Yep, if a float has a hole in it or is saturated depending on the material and sinking, that would explain the gas coming in.

[cowpuc]

Well Jav,, as long as you know you have the carbs isolated for diagnostic purposes - have separated the over flow lines that tie together so they are independent like the non Cali bikes are (go back and click on the part diagrams for the two bike - make sure you have the right "vent" line. Have the tank vent open to atmosphere. Have tested the fuel pump to make sure it shuts off (stops clicking) when the bowl fill.. Thinking your working closer and closer to another time of opening them up..

Is is disconcerting that all of the carbs are getting fuel into the over flows - sure leads one to think something is not quite right with the float valves.. Thinking I would leave the over flow hoses off it - cycle the pump till the bowls fill and listen as the pump slowly clicks off indication its at a holding pressure - watch those over flow nipples and see if they start forming leakage. If they do (and it sounds like they probably will) - take a long wooden dowel, hammer handle or screw drive handle and put it against a float bowel and rap on it.. Possibly you got some floats sticking for some reason..

Sure sounds like you might be dealing with the wrong float valves since they were all just replaced,, just thinking out loud - sure is strange that they would ALL be bad if it were any thing else..

It will be worth the fight once ya get it solved my friend - just the hassle of getting there!!

[Javenmcd]

I'll try and field several questions here.....I did soak the plugs in 100% wintergreen oil. When i reinstalled them they were definitely snug...almost too snug. When I installed the new needles I reused the factory needle clip that straddles the float tang. I've installed clear vent lines so that I'm able to see exactly which vents are doing what. The problem seems to be the same with or without the airbox installed. Obviously I install it on test rides but I've been removing it for idle tests in the garage. Keep in mind that the only time I'm seeing a problem now is after the bike is good and hot and I shut it down. After 10-30 minutes the vents will trickle and leak a few spoonfuls per carb (not always all carbs, sometimes 2...sometimes 3) and stop. Once they've done that the pump cycles again and the bowls refill. The bike isn't flooding out the air bleed jets since I've removed all the emissions crap so it at least starts and runs again instead of choking on gas.

[cimmer]

Was just rereading the whole post and a couple of thoughts came to mind.. referring to the part diagram located here..

http://www.partshark.com/oemparts/a/yam/5107f835f870022108d6576a/carburetor-non-california-model

 

Did you replace the o-ring, item 31 that goes between the main nozzle, item 32 and the jet block, item 30? Also did you use a new gasket, item 33?

Make sure that there is a washer, item 27 on the screw, item 26, that cover the opening into the nozzle area.

Just trying to eliminate possible issue here..

 

Did you replace the main nozzle and needle, item 8, also? I know that the needle is not longer available from Yamaha dang it.. I plan on using a Vmax needle in my replacement. It is possible that if the nozzle and needle were not replace that they as not sealing the opening in the nozzle tightly and it is allowing fuel to get by them and causing the flooding. They do wear and that causing the nozzle opening to get oblong instead of round. It they were tight then I would expect the fuel to rise in the float bowl but not seep out as it is appearing to do now.

 

When you rebuilt your carbs, do you strip them all the way down and soak them in any carb cleaner? Did you blow out all the air passages after cleaning the carbs?

 

I think you have the float levels correct so I am trying to think of what could cause the issue you are having and these things came to mind.

 

I am planning a carb rebuild myself and have been working on getting all the parts I will need and plan on replacing a lot of the parts in the carbs. The ethanol in the gas today just wreck havoc on the parts in this old carb. I figured replace what I can and hopeful have another 20K of troublefree carbs.

 

Good luck and let us know what you find and how it is going..

Rick F.

[Javenmcd]

Thanks Rick. I did replace the o ring and gasket you're asking about in all of the carbs. I felt pretty confident in the job I did as far as attention to detail and cleaning. I'm far from a certified mechanic but I'm not afraid to turn wrenches and have done my own stuff for a few decades (I'm not saying that because I think anyone insulted me or my ability). I didn't replace needles, nozzles etc as they didn't seem to be causing any problems. My original issue I believe was a stuck float in one of the carbs (ironically I wasn't having ANY issues until I added some Seafoam as a treat to the carbs and I think that dislodged something) so I pulled the carbs and figured all of them could use a good cleaning and light rebuild while I was already that far. Now they all seem to leak fuel by upon cool down to some degree. I paid very close attention to the detailed guidelines on the forum here and after many re-reads of the guidelines I still can't see what I would have missed or caused which is why I'm still thinking needles and seats aren't working right. I'm giving the whole process a rest for a week or so as I've ordered OE seats, needles, inlet screens and seat-plug o rings. I decided to do that after watching a Shane Conley youtube video comparing some aftermarket needles to OE stuff. After his demonstration he talked about how easy it is to chase your own tail around thinking of all the possibilities when it just boiled down to inferior aftermarket parts not fitting correctly....at least I should be able to eliminate the needle/seat if that doesn't fix the problem...and if it doesn't it'll probably still leak enough fuel that I can strike a match and throw it on the ground and blow up the Venture like in a Hollywood movie.....I'm so tired of working on it.

[cimmer]

That does make sense on the aftermarket parts. I am going to keep on eye on them and see how it goes. I been looking for the correct replacement needles for the Venture but I am having no luck in locating them so I was thinking of the factory ones for the Vmax. It does have a different taper to it but it is close and might be worth a try.. Least the needles are easy to replace if needed..

Heck most of us here are wrenching on our rides cause we enjoy it and the challenge of keeping them running correctly..

Good luck and keep us informed.. and if we ever need help taking the carbs off, we know who to go to now..

Rick F.

[snyper316]

That does make sense on the aftermarket parts. I am going to keep on eye on them and see how it goes. I been looking for the correct replacement needles for the Venture but I am having no luck in locating them so I was thinking of the factory ones for the Vmax. It does have a different taper to it but it is close and might be worth a try.. Least the needles are easy to replace if needed..

Heck most of us here are wrenching on our rides cause we enjoy it and the challenge of keeping them running correctly..

Good luck and keep us informed.. and if we ever need help taking the carbs off, we know who to go to now..

Rick F.

 

What about the Virago needle sets?

[cowpuc]

Another one of my strange but successful habits I use when rebuilding carbs is that I always put my lips over the fuel inlet on the carb after rebuild (even if I dont replace needle n seat), suck in while I am tipping the carb up to make the float activate. When the air that I am sucking out of the carb bowl stops flowing out I pull a vacuum with my breath against the needle and seat and then put my tongue over the inlet to seal it off.. I leave my tongue in place for 30 seconds or so so I can tell whether or not the seat is holding.. Sounds corny I know but this little habit has saved my from redoing doing carbs a more than one occasion..

[cowpuc]

What about the Virago needle sets?

or that little Yamaha Vision that looks like 1/2 a V-4 Venture motor? Almost sure they use our diaphrams n slide sets in those..

[snyper316]

Another one of my strange but successful habits I use when rebuilding carbs is that I always put my lips over the fuel inlet on the carb after rebuild (even if I dont replace needle n seat), suck in while I am tipping the carb up to make the float activate. When the air that I am sucking out of the carb bowl stops flowing out I pull a vacuum with my breath against the needle and seat and then put my tongue over the inlet to seal it off.. I leave my tongue in place for 30 seconds or so so I can tell whether or not the seat is holding.. Sounds corny I know but this little habit has saved my from redoing doing carbs a more than one occasion..

I use a straw to check that but never thought it to be strange... I have also been checking with wed-40 seems to work pretty good then I move to vent hose and blow gently with carbon drain open to help the wed-40 out.... [emoji317]

 

Living life one curve after the other. Vroom scooting, thru the countryside.

[snyper316]

or that little Yamaha Vision that looks like 1/2 a V-4 Venture motor? Almost sure they use our diaphrams n slide sets in those..

I was thinking because virago 535's share our slides maybe this needle in the middle too same jetblock too I think...

 

Living life one curve after the other. Vroom scooting, thru the countryside.

[CaseyJ955]

I was thinking because virago 535's share our slides maybe this needle in the middle too same jetblock too I think...

 

Living life one curve after the other. Vroom scooting, thru the countryside.

 

From what I can see they with K&L they are different part numbers on the needle valve but if they are similar length and properly fit the ID of the valve seat they should be usable in a pinch. They dont seem that different in price. What would be nice is to be able to find a buyers guide that would help us compare the specs and measurements of each needle valve to see just how they are different.

[snyper316]

From what I can see they with K&L they are different part numbers on the needle valve but if they are similar length and properly fit the ID of the valve seat they should be usable in a pinch. They dont seem that different in price. What would be nice is to be able to find a buyers guide that would help us compare the specs and measurements of each needle valve to see just how they are different.

Yeah well that's where they will get ya if you got all the after markets books thorn your good

 

Living life one curve after the other. Vroom scooting, thru the countryside.

[cimmer]

The issue with just picking needles is there need to be the correct size. Using the Yamaha parts listing for the different bikes doesnt tell us if they will actually fit. If we had the Mikuni part numbers from them might help us get something close that might work.

I have the Keyster K-1359YK carb kit to use on my 4 carbs next month, has to warm up enough in the garage to work. It is made in Japan and does include a replacement needle, labeled as a Y-338, but I have no idea if it work with the Venture as I am guess it is more for the Vmax. I been searching the net for some replacement but not having much luck and am considering a set of Yamaha stock Vmax needles as they still sell them. They are close and might just work and if not, they are very easily changed out.

Here are the measurement I have came up with so far from different sources online.

 

Part no. Mark Slots Length Dist.1 Dia 1 Dia2 K1 K2 K3 K4 K5 K6 A1 A2 A3 A4 A5 A6

J8-5EZ43 5EZ43 1 50.600 3.000 3.000 0.000 16.400 39.400 0.000 0.000 0.000 0.000 1.15 10.00 0.00 0.00 0.00 0.00 Vmax 1200

J8-5DZ03 5DZ3 1 50.500 3.000 3.000 0.000 15.700 36.700 0.000 0.000 0.000 0.000 1.00 8.00 0.00 0.00 0.00 0.00 Venture 1300

J8-5GLZ37 5GLZ37 1 50.500 3.000 3.000 0.000 16.300 20.300 34.300 0.000 0.000 0.000 1.45 3.00 7.00 0.00 0.00 0.00 Venture 1200

 

Anyway if we can find out the part number of the needles in question, we might find something close to use.

Rick F.

[snyper316]

I got lost in what I was saying but pretty much what I meant rick that is the problem we don't know the sizes....

 

Living life one curve after the other. Vroom scooting, thru the countryside.

[Javenmcd]

Anyone ever try to do a wet float level set? While I'm waiting for parts I hooked up to the drain lines on each carb just for sh&ts and giggles. Measured the center on the vacuum slide covers and put a piece of clear line from the drain next to marks I'd made....measured down from that point 16mm per the service manual...the left 2 carbs were spot on but the right 2 were way low. Seems like this method is pretty brainless...the fuel level line on the tubing can't exceed the level in the bowl....but I've no idea why it would be so low on the right side or if the method is flawed. If the level is in fact too low then the needles would constantly let fuel by, correct? Guess that gives me something to grind my teeth about in bed at night while I wait for those parts....cheers everyone.....

[Flyinfool]

Have to ask the obvious question, was the bike on the side stand for this test? It must be straight up and level for this to work right.

 

Turn on the ignition and see if the pump will run to fill the low bowls.

[CaseyJ955]

Since we were talking about wet testing I had planned to wet test my float levels on the bench. I got the carbs together today but found that two of the four bowl drain outlets were broken off so wet testing on the bike is a no go.

 

What I did instead was while the carbs were broken into pairs I did the following.

 

-Set each carb pair on a level surface.

-Pulled the plunger out of a 60ml syringe and plugged it into a 4' length of clear tubing, other end to fuel inlet of carb.

-Using the Syringe body as a funnel I gravity fed each carb individually until it stopped flowing then blew a little pressure into the back of the syringe to make sure the floats were closed firmly. Using the plunger in a 60ml syringe it is possible to overwhelm the needles and force to much fuel into the carb (ask me how I know).

-Disconnected the hose/syringe and dried the carbs keeping them level and let them sit a few minutes to check for leaks.

-I moved the carb over a graduated cylinder and drained the fuel out through the bowl plug and measured the amounts drained, again keeping the carb level other than tilting it forward to fully empty the bowl through the plug port. One could use a small jar and mark the level of the first with a sharpie and compare subsequent bowl volumes.

-I got 42-43.5cc from each carb so I know they are very consistent.

 

Dry bench setting was 1.125" inverted so I guess that worked ok in this case.

 

I read about someone doing this on the bike by leveling the bike and using the drain tube of each carb into a jar to look for consistency, even though it wont give you an actual float level. I mention this in case traditional wet checking is problematic than there is always checking for consistent volume between carbs.

 

I'm quite anxious to find out whats going on with your bike, I've been racking my brain trying to come up with ideas of what it could be.

[Javenmcd]

Well....here's my update. Re-did the seats, needles with genuine Yamaha parts, rechecked all the carb screws, jets, fittings etc. Re-re-re-re set the float levels and re-installed the carbs and......the exact same problem persists. I guess I'm missing something (duh!). I'm selling it. I don't have any faith that I'll ever eliminate the problem or any faith that I'll ever trust it. At this point I really don't care if I lose my behind in the deal (which I most certainly will)...I just want it gone. What a bummer that I've invested SO MUCH time and gotten SO MANY things working and right on the bike only to get my ass kicked by the carbs....someone will turn the right screw or adjust the right mixture and end up with a steal. This afternoon I'd have sold it on the spot for the going scrap rate (8 cents a pound I think)

[snyper316]

Ok at this point I am thinking something crazy going on... I filled my truck up but for some reason last 2 tanks I have gotten 11 mpg its knocking when I first start it, the venture had a mysterious leak. The rebel was getting a measly 71 miles to tank of gas.... And everyone and there brother been having carb problems... Now I would expect 12 miles to a gallon in town from a 5.3 vortech but I haven't been driving it in town...

 

Living life one curve after the other. Vroom scooting, thru the countryside.