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Discussion Starter #1 (Edited)
HELP! Barely runs now...carb cleaning on the bike and re-installing airbox questions

I have tried to read all 17 pages of carb threads and as much info as i can digest from the "verses". I could not find this discussed. When I shot carb cleaner into the back carb drain screw opening while stoping remaining part of opening the cleaner backed up all the way up and out of the vent houses and fuel intake line. However nothing came out the drain on the bottom of the carb. when I did the same to the front carb (shot cleaner into the screw opening cleaner ran out of the dran but did not shoot out the vent or fuel intake line. My question: is the drain on the rear carb stopped up? or is the drain on the front carb open and should be plugged?

Also, the PO had removed the "air cleaners" trying to get the bike to run. I have gathered the necessary stock ears, airbox ect. I have plugged the reed valves, put tubing and t on the carb vents to reach the right air box, and put a hose on the crank vent. I think I am ready to try to re install the stock airbox. Question 2: can I put this airbox in with out pulling the engine and my remaining hair out? Give me advise please. thanks. jmczzz
 

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Dunno bout he airbox, And yes, something on your carb is plugged.
 

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What Duck said- that one carb is plugged.

If you're referring to that "airbox" that is just above the engine, running from front to back, I don't know how you'd get it back in without at least pulling out more hair.... I don't know if it could be done if all the stuff around it was removed. I would guess it could be without pulling the engine, but you know how those pesky engineers can be.

Gotta love those butcher PO's too; I'd have liked to seen him getting it out.

Good luck with it, hopefully someone who has "been there, done that" will jump in...
 

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Correction, I think.... I was just browsing the Verses and the following two sentences jumped out at me, and make me think that, No, you can't get it back in without pulling the engine, though I'm not certain. Here's the two quotes that make me think that- (this is regarding doing the "ear shave")-


It has disadvantages, like it is permanent unless you pull the engine to put everything back.

The worst part was getting the air box out (had to cut it into pieces)...
Just came across this one too-

The only way to pull the airbox without cutting it out is to remove the engine IIRC.
Sure seems like you may just have to bite the bullet, commit to the job and yank the engine...
 

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You may not need to pull the engine if you do it on a hot day or warm up the air box so it's more flexible you just might be able to get it back in.

DT
 

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Or just leave it shaved... a little more power... mild (claimed - I haven't seen one) loss of MPG, many think better looks....
 

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Discussion Starter #7
thanks, duck, doug, dt.
to I think duck means the carb that did not drain out the bottom drain plug. I will try to work on that drain softly with a probe wire. If that doesn't open something up then I guess the carb must come off and be rebuilt.
Question 3: is there such a thing as a rebuild kit like can be had for a auto/truck carb? I even got a rebuild kit for my 52 fergerson tractor. but I don't see one listed on the Kaw site parts?
 

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No, there isn't any kits for these Carbs. I just went thru that whole thing myself not too long ago.

Got to buy the stuff individually.
 

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Discussion Starter #9
and oh yea curtis, shaved may be the only option. but I didn't want to lose any MPG or have to re jet.
BTW question 4: how can I tell what jets are in the carbs now? I doubt the PO butcher did a re jet, but how to know for sure?
 

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I bought my stuff from Ron Ayers. Bike Bandit would have it all too. RA will be a bit cheaper, but it takes about 10 days to get the stuff. No I don't have my list; you look on the website at the parts diagrams, and just add what you want to your "shopping cart". The diagrams are exploded views so you can see what you need.

Stock jet sizes are 38 & 132, and it's usually stamped into the edge of the jet near the top.
Here's a thread with some info and a couple pics- http://www.vn750.com/forum/showthread.php?t=6742
 

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Discussion Starter #12
thanks, I finally got to the main jet num it is a 132. that tells me the PO did not do a ear shave and rejet just threw away the air filters, geez. Now I am gonna try to put an airbox back in and re-install the ears. However I will keep the reed block and not replace the emission tank ect. that will require a block off plate glued over the emmision plumbing grommet hole in the airbox bottom. I have been measuring and think removing the radiator will allow me to slide the airbox in from that angle. What do u think? easier than pulling engine? 3z
 

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Discussion Starter #13
why am I doing this cause i had most of the stock ear parts on hand and I want to keep the mpg up.
 

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Pull your spark plugs and look at the color of the center insulator. The color will tell you whether your carb is lean or rich.

http://www.dansmc.com/spark_plugs/spark_plugs_catalog.html

If you are having trouble at a specific range ( low to mid) Put a fresh set of plugs in the offending cylinder and run the bike at the problem speed for a few minutes. Kill the engine, without letting it slow down (hit the kill switch and pull the clutch) Then pull the plug and check the color. If the plug is white, you are way lean. you want a lite grey to lite brown colour on the insulator. If its darker brown or black or wet you are too rich.
 

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Discussion Starter #16
Installed the airbox by removing the radiator, water themostate then slid the box up and over the engine between the frame members from the front. Had to move wire harness and take the valve cover off front cylinder. It also took a few raps with a rubber mallet and letting the airbox warm up in the sun for a few hours.
There crank vent hose slips over a nipple on the left front bottom of the airbox. there is a hose nipple on the right also I put the carb vent hose from the carb T there rather than on the right airbox. It is a vent for the surge tank (removed) so rather than stop it up I think it is ok to use for the carb vent.
Also discovered that the inside half of the ear i got off ebay is crap. the filter cage bolts spin in the post so i cleaned it as best I could and will use it for test run. Now to oil & install the elements (aftermarket EMGO from Taipei) put the lids on the ears, gas up and see...
 

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Discussion Starter #17
Help! Barely runs now

Well that all was a giant step backwards! The bike spits and sputters. Will only run if the throttle is kept about 1/3 to ½ open and constantly twisted back and forth. Will not idle. Did my shooting carb cleaner up the drain blown out something or dislodge goo that now is stopping up something? I took the just installed ear covers and elements off to see if any effect, no change. I do see plastic caps covering what I think are the fuel/air adjustment screws. Could the PO have used these to cover the lead plugs after changing the settings? I get the location from looking at photos in other threads. I also found a comment that says the mixture screws are factory set at 1 5/8 turn. I think I will see if the plastic caps are covering the mixture screws and see what they are set at and reset at this spec and try again to start. I have ordered a Clymers but right now you guys and the foggy on line manual is the only reference I have. Thanks for the help so far and please keep it up.
3z
 

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You know I have found with an ignition wrench and alot of patience,you
can remove the bowls with the carb on the bike.With a mirror and flashlight
you can see in there pretty good.
 

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No you have to pull the engine to get the air box back under the tank, not as bad as you might think or worse takes me 6 hour,s to take it out longer to put back in,and the carbs are a pain to get in or out with the airbox in,also depends on what kind of pipes or other add on's you might have in the way.
good luck.
 

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Discussion Starter #20
Installed the airbox by removing the radiator, water themostate then slid the box up and over the engine between the frame members from the front. Had to move wire harness and take the valve cover off front cylinder. It also took a few raps with a rubber mallet and letting the airbox warm up in the sun for a few hours.
There crank vent hose slips over a nipple on the left front bottom of the airbox. there is a hose nipple on the right also I put the carb vent hose from the carb T there rather than on the right airbox. It is a vent for the surge tank (removed) so rather than stop it up I think it is ok to use for the carb vent.
 
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