My Vmax performing like a 500cc

VMAX  Forum

Help Support VMAX Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Using the fuel level testing procedure from manual, what are the fuel levels for each carb?

Mark
 
Using the fuel level testing procedure from manual, what are the fuel levels for each carb?

Mark


The manual says I have to use some sort of gauge that I don't have, gives a part number but says to hook up to float bowl drain and loosen up fuel bowl screw, then start the engine for a while, well..

I STILL don't get how to measure fuel levels, the descriptions just don't seem to cut it for me, plus this manual says I need a specific gauge, don't have it, won't get it either, so what's another way? Also my bike won't even start, so how do I follow the instructions on that realm...

From where we left off last year, battery sounding weak, it is super weak.
I have 2 diaphragms that I tried to temporarily fix, one of them had a worse tear so I glued it, when i pull off airbox, i can "bounce" if you will, the slides of the carbs, push em in and hear the ezxchange of air or wahtever that "woosh" sound is...

but the front right carb slide doesn't go all the way... that's the one I tried to fix, gonna have to replace diaphragms, new battery too I suppose, started a thread on that earlier...

what do you all suggest? I can upload vids so u knpow how she sounds but battery dead now, can put on tender for the night, crank her over and u see how it goes from there..? i'll charge it up tonight to get a few good cranks out of the bike tomorrow.

GOTTA GET THIS PILE OF CRAP GOIN!
 
You dont need that fancy gauge. Fish tank hose or any clear hose you can push into or onto the end of the bowl drain tube. Just hold up like they show for the gauge.

Diaphragm replacement isnt too bad, there is an ebay seller out of the UK that sells a set of four for $100 shipped if you need those. I just threw some on my Venture and they are decent and not the shitty Chinese ones or expensive OEM.
 
http://www.vmaxforum.net/showthread.php?t=17274

Read this thread on wet fuel level check. As Casey noted, just need some clear tubing. Buy a foot of it at the hardware store for less than $1. You only need a few inches.

Put a mark on the hose 17mm from the end. Push the end without the mark over the OEM drain tube. Hold the other end up to the casting mark on the carb.

Open the drain screw. Cycle the fuel pump. Observe fuel level. If float is set correctly the fuel should be right at your mark, 17mm down from the casting line.

As far as diaphragms, replacements rubbers are much more reasonable than the whole slide.

Ive heard a few mentions of using Loctite PL S30 roof and flashing sealant to cover some minor pinholes on this and another forum. Cant say for sure if its a good idea. Supposedly fuel resistant once cured. Definitely flexible as I've used it for its intended purpose.

Sent from my SM-G930V using Tapatalk
 
The PL S30 is impressive, I tried that first but I think I put it on a little to thick and a couple diaphragms had several holes so I opted for the replacement set for only $100. If I just had to mend a pinhole or two I would roll that tube out again but the ones in my Venture were pretty ragged and 30yrs old.

Next time I use PL S30 I will apply tiny dabs with a toothpick.
 
ok guys update. did the whole wet float test. so here's a bit of info that woulda been nice to know.. the O.D. of the drain tube is 1/4". I found a piece of clear plastic tubing with a 3/16" I.D. Gotta squeeze that in there but got a good seal. Here are the pics. they are Carbs 2,1,3,4 respectively. Carb 4 didn't fill the tubing as fast as the others when i opened up the drain screw. I turned the key several times and for Carbs 2,1,3, the pump may run for a little bit, then shorter, etc. For Carb 4 though, the tube was full of gas and when I turned the key to On, the pump would run for a good 3 seconds, every time... so not sure if that is significant, but...

SO Carb 2 was exactly at 17mm. I made lines like ------[ ]-------- 15 and 17mm. Carb 1, bad pic but looks low. Carb 3 is a bit high and Carb 4 low.

So next step, take off carb rack after draining bowls, and fix float level?
 

Attachments

  • IMG_0274[1].jpg
    IMG_0274[1].jpg
    50.2 KB · Views: 17
  • IMG_0275[1].jpg
    IMG_0275[1].jpg
    47.2 KB · Views: 16
  • IMG_0276[1].jpg
    IMG_0276[1].jpg
    65.5 KB · Views: 16
  • IMG_0278[1].jpg
    IMG_0278[1].jpg
    62.5 KB · Views: 14
ok guys update. did the whole wet float test. so here's a bit of info that woulda been nice to know.. the O.D. of the drain tube is 1/4". I found a piece of clear plastic tubing with a 3/16" I.D. Gotta squeeze that in there but got a good seal. Here are the pics. they are Carbs 2,1,3,4 respectively. Carb 4 didn't fill the tubing as fast as the others when i opened up the drain screw. I turned the key several times and for Carbs 2,1,3, the pump may run for a little bit, then shorter, etc. For Carb 4 though, the tube was full of gas and when I turned the key to On, the pump would run for a good 3 seconds, every time... so not sure if that is significant, but...

SO Carb 2 was exactly at 17mm. I made lines like ------[ ]-------- 15 and 17mm. Carb 1, bad pic but looks low. Carb 3 is a bit high and Carb 4 low.

So next step, take off carb rack after draining bowls, and fix float level?

Look at the round tab at the top of your fuel enricher you will see a line on the carb body that is equal to that-make all the levels of the gas in the tube line up there.
 
http://www.vmaxforum.net/showthread.php?t=17274

Read this thread on wet fuel level check. As Casey noted, just need some clear tubing. Buy a foot of it at the hardware store for less than $1. You only need a few inches.

Put a mark on the hose 17mm from the end. Push the end without the mark over the OEM drain tube. Hold the other end up to the casting mark on the carb.

Open the drain screw. Cycle the fuel pump. Observe fuel level. If float is set correctly the fuel should be right at your mark, 17mm down from the casting line.

As far as diaphragms, replacements rubbers are much more reasonable than the whole slide.

Ive heard a few mentions of using Loctite PL S30 roof and flashing sealant to cover some minor pinholes on this and another forum. Cant say for sure if its a good idea. Supposedly fuel resistant once cured. Definitely flexible as I've used it for its intended purpose.

Sent from my SM-G930V using Tapatalk

I use to have an XJ650 maxim.. those slide slide diaphragms were pretty expensive so we use to do a similar thing on them.
 
OK I'm obviously donig the test correctly as per Madcmb's directions.

Someone please provide me with the proper next step. LIke I said. take carb rack out now and tweak the float levels?

Is there an easier proper way to do this aside from taking the carbs completely separate and apart?

Should I just clean out the damn things anyways if I gotta go in there? I already did total rebuild with new gaskets etc before winter. hundreds in new parts, ain't doin that again.
 
OK I'm obviously donig the test correctly as per Madcmb's directions.

Someone please provide me with the proper next step. LIke I said. take carb rack out now and tweak the float levels?

Is there an easier proper way to do this aside from taking the carbs completely separate and apart?

Should I just clean out the damn things anyways if I gotta go in there? I already did total rebuild with new gaskets etc before winter. hundreds in new parts, ain't doin that again.

Why would you not clean them when you have them off? Opportunity.
You do not have to completely take them apart just the 2 side brackets with the 4 screws. Set the floats as close to the 1/2 moon mark with the circle then put them back together and do a wet test.
 
Yeah i did guys, thanks. Thanks for all your help too everyone.

Is it not clear what I did given the photos I took? I rotated the best one see you all can see.
What you can't see is that the top of the clear tubing is lined up with the mark on the carb body.

Someone should compile a GOOD wet test post and sticky it. Use this photo. All the other threads or posts are somewhat incomplete or unclear. The one mentioned is good but it is an angled blurry photo and you can't see the whole operation in action, like my photo does.

So obviously this carb is running too rich, since it's above the 15mm mark.

Ok so next step.... and I'll do this after work today..

1.) Unhook the throttle body linkages from carb
2.) Make sure carbs drained. disconnect fuel lines from carbs.
3.) pull carb rack off disconnect carbs and reset float levels
4.) I guess I should clean them out too, make sure jets clear, especially the super small one in the jet block. all the others have decent size orifices.

Not replacing any gaskets, even jet block gasket, just how it's gonna be this time.

5.) In an earlier mention, it was said that I should wet test again after resetting. makes sense. Can a guy test out the float level after resetting it internally, without having to mount carb rack back on bike? I'm assuming a guy has to put the rack back on the bike, hook up the fuel line, turn the key, let the bowls fill up, and do the wet test again to check.... is this the only way to test once resetting floats?

I'll find the proper half moon mark thing. swear I did this right last year when rebuilt carbs, but bike never ran properly even though I swear I did this, so we'll see I guess..
 

Attachments

  • Wet_Test.jpg
    Wet_Test.jpg
    65.8 KB · Views: 16
Yeah i did guys, thanks. Thanks for all your help too everyone.

Is it not clear what I did given the photos I took? I rotated the best one see you all can see.
What you can't see is that the top of the clear tubing is lined up with the mark on the carb body.

Someone should compile a GOOD wet test post and sticky it. Use this photo. All the other threads or posts are somewhat incomplete or unclear. The one mentioned is good but it is an angled blurry photo and you can't see the whole operation in action, like my photo does.

So obviously this carb is running too rich, since it's above the 15mm mark.

Ok so next step.... and I'll do this after work today..

1.) Unhook the throttle body linkages from carb
2.) Make sure carbs drained. disconnect fuel lines from carbs.
3.) pull carb rack off disconnect carbs and reset float levels
4.) I guess I should clean them out too, make sure jets clear, especially the super small one in the jet block. all the others have decent size orifices.

Not replacing any gaskets, even jet block gasket, just how it's gonna be this time.

5.) In an earlier mention, it was said that I should wet test again after resetting. makes sense. Can a guy test out the float level after resetting it internally, without having to mount carb rack back on bike? I'm assuming a guy has to put the rack back on the bike, hook up the fuel line, turn the key, let the bowls fill up, and do the wet test again to check.... is this the only way to test once resetting floats?

I'll find the proper half moon mark thing. swear I did this right last year when rebuilt carbs, but bike never ran properly even though I swear I did this, so we'll see I guess..

Follow this for a DRY float level check, and it will EQUAL a wet level of 17 mm.

http://www.vmaxforum.net/showthread.php?t=1427
 
Follow this for a DRY float level check, and it will EQUAL a wet level of 17 mm.

http://www.vmaxforum.net/showthread.php?t=1427

Thanks Yep, looks familiar.
So that measurement (if not going by the circle edge on a circle) is from the float down... but see how the body is curved at that exact point? the inside corner is kinda curved, so how does one get an accurate measurement and consistent?. just a thought... how do you guys all do it? i'm sure everyeone else here has done this whole thing way more many times than myself.... do ya go the circle or do ya go with measurement?
 
Thanks Yep, looks familiar.
So that measurement (if not going by the circle edge on a circle) is from the float down... but see how the body is curved at that exact point? the inside corner is kinda curved, so how does one get an accurate measurement and consistent?. just a thought... how do you guys all do it? i'm sure everyeone else here has done this whole thing way more many times than myself.... do ya go the circle or do ya go with measurement?

The circle will get you close but not as reliable as a wet test.
 
The circle will get you close but not as reliable as a wet test.

ok thanks. so sounds like I just need to get it close. re-install, do wet test, take apart, adjust, etc etc. ugh.. frickin hell ok. well i'll get that done today and report back. thnx guys, you are all the true masters.

can I do a wet test without installing back on bike? I'm assuming ya gotta set it down on bike, hook up fuel lines and that's it... no need to hook up throttle again... etc..
 
Back
Top