Kawasaki VN750 Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
63 Posts
Discussion Starter #1 (Edited)
Thought I would start a new thread, since my problems vary with electrical and the dang carbs.

To Recap everything, bike ran horrible, surged and backfired. Did a carb clean, bloodying my knuckles and all. Then it ran sweet..

Butt............................

The temp gauge quit working. Checked wiring and all was good there, so its a sensor.. Btw, tried getting the sensor off, and it won't budge, the factory used some good sealant.

Tonight I pulled the carbs again, guess what!!! No bloody knucles, only took about 15 minutes to get them out.

Now for the questions.

Cleaning first. Last time I cleaned the jets with carb spray and all the other parts, minus the rubber ones. I did not seperate the carbs to do this.

I went to auto zone to see if they had the carb tank to dip the carbs in, but they didn't..

So, since carbs are off. What should I do now.???

I don't mind buying new jets, not rich here, but they are inexpensive.

Should I just go with the ear shave now, get rid of that surge tank and help solve some prolbems. If so what is the best step.

Since for now the sensor won't come off, and it is the warm season. To be safe should I pull out the thermostat. Speaking of that , when you pull the carbs you have to take out the thermostat housing and lose some coolant in doing so. Should I do that coolant bleed thing? Would that have caused my sensor to fail?

Also I did do the coaster marble trick, and wow it did make a difference in the backfire.

Also did the manual cam tensioner on the front cylinder.
 

·
Registered
Joined
·
63 Posts
Discussion Starter #2
Update. Well I just called my local dealers. No one has the jets in stock, so I would have to order them. The jets look ok after I cleaned them.

I could not get the float housing off, the screws seem to be in super tight, I wanted to check if something was floating in there causing the problem. Anyone know a good trick to clean that area out?
 

·
Once Banned
Joined
·
2,125 Posts
What has always worked for me is to use a screwdriver to take the housing off.



OK, ok, get some penetrating oil. Like other many things in this world, it works, but I don't know why. You spray it into the nonexistent gap between the screw and the housing, then wait 15 minutes, and put a lot of pushing and turning force on the screwdriver, and they pop loose.
 

·
Registered
Joined
·
87 Posts
PB spray

Spray some PB spray on the screws.In my case,the float needle is probably blocked.Need to clean that area.Very important.If you clean your carbs,the float chamber needs attention.
 

·
Registered
Joined
·
63 Posts
Discussion Starter #6
Update again

Well I got the carbs cleaned and back on. I never got to the float section, but was able to spray some cleaner up in there and flood em and drained.

After I got every thing back together. The idle is much more consistent now. I don't feel the lurching as much. But the bike now seems gutless, feels like I went from a corvette to an escort.

It also sounds alot louder now, a nice loud though. But I don't think this is normal for it.

I did adjust the A/f screw to 2.25 then 2.5 and then 3. Then back down to 2. I didn't really notice any difference.

After it cools down I am going to check all my lines, to make sure none were kinked.

For a moment I smelled smoke near my battery area, but I think was just some of the coolant that I spilled burning off, nothing felt hot to touch in that area, but then again who knows.

Would the carbs not being synched be causing this? Or am I missing something. If the float bowls were flooding wouldn't I smell gas?
 

·
Premium Member
Joined
·
1,647 Posts
Carbs out of sync could cause one cylinder to run lean (usually the rear) while the front runs rich. There is a link in the verses that tells you how to make your own manometer so you can sync your carbs. It isn't hard to do at all.
 

·
Registered
Joined
·
63 Posts
Discussion Starter #8
Thank you. I will try that.

One more thing I just remembered, I did replace all of the lines coming from the carb.

The 2 outer lines coming from the petcock are a hair smaller in diameter hole wise, could this be a suspect? The middle smaller line was the exact same. When I bought the lines I just the clerk what they were, is there a difference between those made for fuel and just vacuum lines?

Also to make sure I am correct where do the forward and rear lines on the petcock go to on the carb, just in case I have them backwards.
 

·
Premium Member
Joined
·
1,647 Posts
The smaller diameter hose is the vacuum line that runs from the carb to the center petcock nipple. Without it, fuel won't flow. The other 2 lines feed fuel to the carbs. It really doesn't matter which line goes to which carb as long as there are no air leaks and the like. On mine the forward line goes to the front cylinder carb and the rearward line to the rear cylinder carb. The wrench that rebuilt my petcock told me that the vacuum line should not need hose clamps. He replaced the one I had on it with a smaller diameter line.
The main fuel feed line diameter shoudn't be a problem as long as they fit over their respective nipples and seal well. It's the float valves and jets that determine how much fuel gets to the cylinders. As long as the float bowls have enough fuel in them to power the bike, that's all that matters.
 

·
Registered
Joined
·
63 Posts
Discussion Starter #10 (Edited)
Thank you. Thats good to know. I checked all the lines, none are kinked. I may just have to pull them again. What is really baffling me is why it is louder.

There is a mechanic only 10 miles from me that offered to clean them out it from is house for $100 and he will synch them. If by morning I don't get it figured out, I will probably go to him.

By no means am I a carb mechanic.

Something odd, probably not related, but this all happened the same day I installed the manual cam tensioner...hmmmmm...

Also the day after I was going to trade it for another bike... Like I said before it is just possesed.

Oh and the coolant gauge works now.. go figure....
 

·
Registered
Joined
·
63 Posts
Discussion Starter #11
Another Update

Today I blew out the tank, cleaned the filter (I did find a few pieces of dirt or rust floating in the filter). When I drained the gas I drained it through a coffee filter and did find sediment (looked like sand).

Also cleaned out the old fuel lines and put them back on. They were bent to shape and the newer lines were kinking slightly.

Took the bike for a spin. No more hiccup, no more loud exhaust sound, runs smooth (only tested it to 45mph, nervous about the fuel lines cause I couldn't get the clamps on them at the base of the carb, will have to take off the air ducts to the surge tank again to get to them.)

I am going to get some tank cleaner tomorrow and clean the tank out really good.
 
1 - 11 of 11 Posts
Top