Carb sync woes

[Tysons87venture]

Hey everyone, I am having some carb problems and wondering if I can get some pointers or lead in the right direction 

I have some gas-carbon splatter coming out the right side exhaust, spark plugs are dark and 1 was fouled, also noticed a drop of gas under exhaust from sitting.

Next thing is I hooked up my new carb sync tool, and show nothing on cylinder 1,  with 3 and 4 being relatively in sync as shown in my photo, to those with experience what does this mean? I am a newbie with this stuff but I'm afraid to keep running bike as I dont want to damage engine. My gas mileage is terrible, I get about 120km for 13 liters

 

[BlueSky]

Have you checked the engine compression?  I would do that first just to make sure the engine is okay.  

[Tysons87venture]

Compression showed 120s for the front 2 cylinders, 140s for back 2

[Tysons87venture]

I believe the problem to be with the carbeurator, probably when I put it back together, i am new to all this stuff and I did bench sync but whether I did all the stuff proper who knows,  bike does run great even at the low psi but it's getting tons of fuel, was hoping I didnt have to take carb off again but it is looking that way

Wish I could have a mechanic work on bike but no one is interested in my area or the ones who will work on it would only do it in winter so this site has been a huge help with the project

[saddlebum]

What all did you do to the carb when you had it off?

[Tysons87venture]

I did buy a carb rebuilt kit and used some new jets and gaskets which were probably cheaply made as I dont think I spent alot of money on it.

So I blasted out all the passageways with carb cleaner, there is 1 air fuel mixture screw on cylinder 4 that is stripped and seized. I did compare the jets to old ones when replacing, I did also have the enricheners pulled part and replaced a gasket their from what I remember

 

[saddlebum]

 

6 minutes ago, Tysons87venture said:

I did buy a carb rebuilt kit and used some new jets and gaskets which were probably cheaply made as I dont think I spent alot of money on it.

So I blasted out all the passageways with carb cleaner, there is 1 air fuel mixture screw on cylinder 4 that is stripped and seized. I did compare the jets to old ones when replacing, I did also have the enricheners pulled part and replaced a gasket their from what I remember

 

Did you replace the needle and seats, and set the float levels

 

Edited July 10, 2021 by saddlebum

[Tysons87venture]

This was the kit I used, I re used the original float needle valves as when i put these ones in i had gas pouring out the overflow onto the ground. The carbs have been pulled out of bike about 5 times now so I've gotten it doen but not looking forward to doing it again lol

[saddlebum]

When you rejoined the four carbs did you set them on a tue flat surface. I like to use a piece of granite countertop for this, most granite places have scraps they will just give you.

[Tysons87venture]

I believe I need to find the tech talk that refers to adjusting float heights, etc. I really didnt know what I was doing when it came to setting them, I benched all the throttle plates the same by using a thin paper clip from what I remember

I love the way it's running but i know it's not healthy and the mileage is brutal

I think maybe i need some better parts to maybe, I've learned it's not worth buying cheap parts on this project

[Tysons87venture]

I believe the surface on the work table was flat, I remember using a torpedo level across the bodies to verify

Does the reading from the sync test tell me that I have a serious vacuum leak? I guess meaning I have no vacuum at all on that cylinder unless my brand new meter is sticky, maybe I needed to play around with it more. Also there was fuel coming out of carb holders where I pluged sync hoes into

[saddlebum]

Thee factory way is to set the float height while on the bike which is a real PITA. Some use a dry set bench  method which you should be able to find in the tech section. I devised a  rather different approach. I attached a PDF as to how I do it. 

Home made set up for wet setting floats on the bench.pdf

[saddlebum]

2 minutes ago, Tysons87venture said:

Does the reading from the sync test tell me that I have a serious vacuum leak? I guess meaning I have no vacuum at all on that cylinder unless my brand new meter is sticky, maybe I needed to play around with it more. Also there was fuel coming out of carb holders where I pluged sync hoes into

The sync tool measures vacuum to get its reading. Therefore a vacuum leak can definitely effect the reading of your sync tool.  Also it is possible for the rods in the sync tool to become sticky but you can check this just by swapping the hoses from a high reading carb with a low reading one. If you get the same reading your tool is ok but if your readings also swap then your tool is sticking.

Assuming you are connecting to the proper tubes which are the ones with caps on them except for one on the left side which will have a hose connected to it there should be no gas coming out of those tubes if there is you have a problem.

[Tysons87venture]

Brilliant, I will have to see if I can build something like this

[Tysons87venture]

Good to know,  they were pretty wet and was definitely fuel, so looks like I need to pull carbs again and hopefully do it right this time

[saddlebum]

The nice thing about my float setting set up is while using it I discovered one of the needle seats had stuck open and flooding so I was able to correct it before putting the carbs back on the bike which saved me the hassle of discovering it after putting the carbs back on and  having to take the carbs back off again. Had I used the dry setup technique I would not have caught this issue until after.

[larrydr]

I had a Virago that had problem much like that ..I found that the floats in the carbs were caught on the inside of the float bowl ...I could change plugs it started out okay , and  ten minutes same problem over again .. I pulled the carbs and found tiny little marks inside the float were the floats would stick...Good Luck

 

[BlueSky]

The float level can be checked without removing them.  Check the manual.  A clear tube is connected to the drain and held up to see where the level is.  Adjusting the level is a different story.

[Tysons87venture]

Thank you, in your experience would a float that is set to high cause fuel to come out at the carb holders where the plugs are? And would it cause fuel to spit out exhaust pipe? I really dont have a good understanding of how these carbs work and I think that's half my problem when working on them 

I think I am going to do as per manual and hook up a plastic hose to drain and see where level is at and then pull carb off again, not looking forward to it.

[saddlebum]

59 minutes ago, BlueSky said:

The float level can be checked without removing them.  Check the manual.  A clear tube is connected to the drain and held up to see where the level is.  Adjusting the level is a different story.

This is  correct the clear tubes I show in my PDF can be attached to the carbs and you can check running float levels this way but (A) I find access to these a real PITA with the carbs mounted and (B) if you do manage to place the tubes in place of the drain plugs and find the levels are off you have to remove the carbs anyway. In my case I find my mitts just can't get in there.

Edited July 10, 2021 by saddlebum

[BlueSky]

When I checked the float levels in my 89, as I remember, I put slightly larger tubes over the ends of the drain tubes and it was very easy to check the levels.  

[Tysons87venture]

Got carbs apart and dont really know what I'm looking for

Only thing I can see is the float needle valve

Is it suppose to move? Like the whole unit not just the spot that blocks off the fuel? Is there a certain way this needs to be installed?

[saddlebum]

2 hours ago, BlueSky said:

When I checked the float levels in my 89, as I remember, I put slightly larger tubes over the ends of the drain tubes and it was very easy to check the levels.  

I may have to revisit that and take another look at it for my own curiosity.

[Tysons87venture]

[saddlebum]

4 minutes ago, Tysons87venture said:

Got carbs apart and dont really know what I'm looking for

Only thing I can see is the float needle valve

Is it suppose to move? Like the whole unit not just the spot that blocks off the fuel? Is there a certain way this needs to be installed?

The needle is the only thing that should move the brass seat the needle goes into should not

Edited July 10, 2021 by saddlebum