83 Venture, high vacuum #4 carb, wrong jet #1 carb

[Droneh8tr]

Ok, my 83 Venture is back together enough to test ride... But all is not well... But close:)

The right front carb, #4 I think, has a very high vacuum reading. Turning the adjustment screw didn't do anything. I looked into the top of the carb. and the throttle valve is moving during throttle movement. I switched the hoses on the carb. sync tool and the problem moved with the hose. The other 3 carbs are nearly perfect in vacuum.

 

While looking down into the carbs, I saw that the #80 jet in #1 carb was wrong.. I had put the 42.5 in....

Sssoooooo

I'm pulling the carbs. now, is their something I can look for to help the vacuum issue with #4 carb..

WAIT... also I noticed the left front carb slide not moving at the same point as the other 3. It take a higher rpm before it starts to react..

 

****UPDATE***

The jet issue is fixed....

The slide is ok now.....

Regarding the vacuum issue, I can make each right side carb be the same very high vacuum... BUT, when I go to make them match the left, the 3 carb will come down but the 4 carb will stay high.. Do I have a linkage issue? I didn't see that anything was wrong when I pulled the carbs off. ANY input would be appreciated..

 

OK, that's all for now... ANY IDEAS WELCOME.

Edited May 18, 2014 by Droneh8tr
Solved several issues

[Peder_y2k]

"also I noticed the left front carb slide not moving at the same point as the other 3"

 

#2 carb has damaged diaphragm, ie holes, rips or tears. Also, diaphragm cover o-ring could be missing. Slide may be partly stuck in bore, check for free movement by pressing it open with your fingers and watching for free return.

-Pete, in Tacoma WA USA

[Droneh8tr]

"also I noticed the left front carb slide not moving at the same point as the other 3"

 

#2 carb has damaged diaphragm, ie holes, rips or tears. Also, diaphragm cover o-ring could be missing. Slide may be partly stuck in bore, check for free movement by pressing it open with your fingers and watching for free return.

-Pete, in Tacoma WA USA

 

Thanks Peder_y2k, I took off the cover and no rips, tears and the o ring was there... But it appears that just pulling it off may have fixed it.. It looks like its working right. Thanks for the reply.

[Venturous Randy]

Regarding the vacuum issue, I can make each right side carb be the same very high vacuum... BUT, when I go to make them match the left, the 3 carb will come down but the 4 carb will stay high.. Do I have a linkage issue? I didn't see that anything was wrong when I pulled the carbs off. ANY input would be appreciated..

 

OK, that's all for now... ANY IDEAS WELCOME.

 

It sounds like you may have a linkage issue. You also need to check to see if you have a leakage issue. Any time you are having any difficulty with vacuum issues, you need to make sure you do not have any vacuum leaks by spraying around the boots and manifolds. This can have a big impact on trying to sync.

RandyA

[Droneh8tr]

It sounds like you may have a linkage issue. You also need to check to see if you have a leakage issue. Any time you are having any difficulty with vacuum issues, you need to make sure you do not have any vacuum leaks by spraying around the boots and manifolds. This can have a big impact on trying to sync.

RandyA

 

Thanks, I'm gonna make that project #1 for tomorrow morning..

[Venturous Randy]

Thanks, I'm gonna make that project #1 for tomorrow morning..

 

I meant to say that I spray with starter fluid and there is a noticeable increases in RPM's when I hit the leak.

RandyA

[Prairiehammer]

Don, after reviewing several of your threads concerning this bike and carbs, there could be a couple things that would cause your current issues.

 

When you reassembled the carbs, did you have the carbs on a flat surface plate as you finalized the joining of the four carbs? The alignment of the four individual carbs, especially regarding the linkage, is important when making up the rack.

 

Secondly, you have California carbs. On the California carbs, there is an additional port on the carb with an accompanying hose. This port is located on #2 (left front) carb body above the butterfly. It is similar to the 1983 carb in respects to that port. Whereas on the non California 1983, it is routed to the 'boost sensor' (vacuum advance), in the California version it is routed via hose to the charcoal canister. Perhaps that hose from #2 is disconnected at the other end? That would result in a huge vacuum leak.

 

Thirdly, since your bike had the YICS, perhaps one or more of those hoses and/or the YICS chamber is leaking?

[MiCarl]

One more suggestion for you:

 

After you assemble the rack either eyeball the butterfly opening gaps or measure with a small wire. If you get them all close on the bench the vacuum syncing will go much smoother later.

[Droneh8tr]

Don, after reviewing several of your threads concerning this bike and carbs, there could be a couple things that would cause your current issues.

 

When you reassembled the carbs, did you have the carbs on a flat surface plate as you finalized the joining of the four carbs? The alignment of the four individual carbs, especially regarding the linkage, is important when making up the rack.

 

Secondly, you have California carbs. On the California carbs, there is an additional port on the carb with an accompanying hose. This port is located on #2 (left front) carb body above the butterfly. It is similar to the 1983 carb in respects to that port. Whereas on the non California 1983, it is routed to the 'boost sensor' (vacuum advance), in the California version it is routed via hose to the charcoal canister. Perhaps that hose from #2 is disconnected at the other end? That would result in a huge vacuum leak.

 

Thirdly, since your bike had the YICS, perhaps one or more of those hoses and/or the YICS chamber is leaking?

Yes, I did put the carbs on a level surface. I've looked at pictures of the linkage and simply don't see that anything is on wrong

The vacuum advance hose is in place, connected on both ends, but I'll look closer for any leaks.

YICS system leaking... Interesting. I'll try pinching the hoses and see what happens.

 

 

One more suggestion for you:

 

After you assemble the rack either eyeball the butterfly opening gaps or measure with a small wire. If you get them all close on the bench the vacuum syncing will go much smoother later.

Thanks MiCarl, I did just that. But still the vacuum was VERY high. What it's doing is that either 3 or 4 can be adjusted, but not both together..

 

I've got some ideas to look at so let me do those and get back to you all.

[Prairiehammer]

Don, here is where the engine number can be found.

[Droneh8tr]

Don, here is where the engine number can be found.

 

I'm chuckling to myself because I knew that's where it's suppose to be, BUT THEIRS NOTHING THEIR... I thought maybe I was looking in the wrong area..

it is a raised section that kinda looks likes a file.. But not something somebody did, but rather like it came like this from the factory.

Any other areas I should look?

[Droneh8tr]

Alright L&G, this is what it's doing..

1 and 2, sync fine.

I can sync 3 to 4, but remember 4 is very high...

Now, when I try to sync 3 and 4 to 2.... I run out of adjusting screw long before their synced.. So now I'm being left with 3 and 4 with high vacuums and no more ability to adjust them down...

I've looked at the linkage and really can't see how it could be put on wrong... I don't see anything bent broken or missing..

Does someone have a pic of exactly how the linkage should look..

Thanks for putting your knowledge to work on my issue..

 

I have to run to a friends house now, he's having issues with his radiator, I'll get back with you all later today.

[Prairiehammer]

I'm chuckling to myself because I knew that's where it's suppose to be, BUT THEIRS NOTHING THEIR... I thought maybe I was looking in the wrong area..

it is a raised section that kinda looks likes a file.. But not something somebody did, but rather like it came like this from the factory.

Any other areas I should look?

 

Perhaps the crankcase has been replaced as a part and has no number? Should look like this:

 

[Peder_y2k]

Thanks Peder_y2k, I took off the cover and no rips, tears and the o ring was there... But it appears that just pulling it off may have fixed it.. It looks like its working right. Thanks for the reply.

 

If that fixed it, then the base of the slide spring was not in proper position inside the cover, and when you replaced the cover, it was properly seated. This has happened to me, and was discovered with the finger push. Now I always check my carb work with the finger press of the slide to check for proper spring action and to observe for any sticky-friction.

[Peder_y2k]

 

Now, when I try to sync 3 and 4 to 2.... I run out of adjusting screw long before their synced..

 

I encountered this situation once on my '88. I had to reset the system of adjusting screws by turning them all back to no contact with cams and start over. System works perfectly now.

[Droneh8tr]

I encountered this situation once on my '88. I had to reset the system of adjusting screws by turning them all back to no contact with cams and start over. System works perfectly now.

 

Please, Please, please be more specific... I want to try what your saying... Do I back out all the screws, is that what your saying?

[Marcarl]

If your #4 carb is very high I would suggest that it is way out. Here's how I see it. In order to get any vacuum at all, the butterfly needs to be closed, or very nearly closed. The point of the procedure is to get all the butterflies to be the same, so knowing now that the BF needs to closed to get vacuum, it stands to reason that the #4 BF is closed,,,, completely. So you can start from scratch as has been suggested or you can try to open up #4 and then go through the whole process again,, it might work and it might not for you. If you want to start again, start with # 2, set it with the idle speed screw so that it contacts a thin wire, then go around adjusting the others so they are the same. I would use a long thin copper wire. By using a wire you can easily see when the BF contacts the throat of the carb. Now start it and do a sync.