What happened?

[JMNTX]

New subscriber, first post. My 90 VR that I've had for about 6 months was running great, on the way home last month. All of a sudden it started running rough acting like it was running out of gas, I had just filled the tank. Choking it to keep it running couldn't give it any throttle I made it. First I changed the filter no luck. then I got busy. I drained the tank no trash no water, checked the fuel pump it would pump gas across the garage. Took the fuel line loose from the carburetor inlet turn the key I'm getting gas at all four carbs. It will only run when I spray B12 into the throats. I inspected the diaphragms couldn't see any tears or holes. I cleaned the jets and replaced the intake boots. I don't know what else to try. OH I for got I let sea foam set in the carbs for three days, changed the plugs, installed a new stator and a used starter clutch. Its turning over really good but still won't start. Can anyone help me?

[cowpuc]

Hi Jm and a healthy to VR!! Also, THANK YOU for becoming a Supporting Member my friend - the support in keeping our/your club operating for all our benefit is appreciated!!

To your question..

I would locate the drain screws on the bottom of each carb, open the screws and drain the bowls. Then I would turn the key on and off to cycle the fuel pump and watch the carb drain tubes and make sure I am getting fuel up to the carbs and into the bowls - close em one at a time when they spurt fuel to make sure all carbs are filling. After all drains are close, keep turning the key on and off allowing the fuel pump to cycle thru each time - keep doing this until the fuel pump audibly slows down to a stop signifying the carb bowls are full. Try to start it and see what happens - should start with choke and be able to slowly move choke off.

By cleaning the jets in the carbs you probably cleaned the float valves too?, you may have stuck floats and they just need some jostling to get em settled in.

Any chance the ride back when this all began was a wet one JM? Any chance that your issue could be related to getting the bike itself wet, so we may be dealing with an electrical issue? Didnt notice your tachometer acting funny when it was acting up did you?

[JMNTX]

It wasn't raining or wet roads it was a typical TX day hot. As to the drains and pump. When I turn the key the pump just runs for a second then stops. What little gas was in the bowls ran out. Then nothing. Would I have addressed this by running a ground and hot wire from the battery to the pump? I had tried that.

[cowpuc]

Thats why I suggested turning the key on and off to let the pump cycle. The pump is set up to operate just momentarily when the key is turned on - what your scoot is doing is normal. Not sure how hot wiring the pump by running it directly off the battery would affect the entire system as far as getting the bike to actually run. I would suggest going back over my initial response and reading it carefully and following it thru so we have a baseline to start with.

Close the drains, turn the key on, leave it on till the pump quits pumping, turn the key back to the off position and then back to on again, the pump will cycle thru again.. Keep doing this until the pump slows down and quits pumping meaning the carbs are full. This should not take long, probably less then 15 pump cycles to fill the carbs (never have actually counted the number of times it takes to fill the carbs). After the carbs fill by doing what I am talking about, attempt to start it normally and see if it will start. Try doing that and then get back with me..

[JMNTX]

The pump only runs for two seconds. Turning it off and on after that with no results. Wait about an hour then turn the key it cycles for about two seconds after that nothing also the bowl drain screws are backed out but no fuel comes out after the first little bit?

[cowpuc]

Is the battery fully charged? If it is, go ahead and turn the key off and then back on until the pump refuses to come on when the key is turned on. Leave the key on and tap on the face of the fuel pump with the handle of a screw driver - these pumps have a set of contact points in them that like to wear out over time - see if tapping on it will get it to run momentarily. It almost sounds like you have a fuel pump with bad or dirty points.

Another way to check and see if it is the pump is to disconnect the output hose from the fuel pump, take a squirt bottle of gas (I use an empty gear case oil bottle with the little nipple on the end to slide into the fuel line for this kind of stuff) and attach it to the output hose that leads to the carbs. Close the carb drains and squeeze the bottle of gas until I feel it not moving fuel into the carbs. Slide the output line back on the fuel pump so I dont shoot gas all over if the pump starts back up. Try to start the engine and see if it will run the gas out of the bowls..

You can also do the same thing with a syringe full of gas shot thru the drain tubes on the carbs - basically filling the carbs thru the drains.

 

Just thought of this!! Another thing you could try is pressurizing the fuel tank thru the vent hose. Putting air pressure into the tank should move fuel thru the pump and into the carbs. The vent hose runs down the frame spar on the right side of the bike (as you are sitting on the bike) under the right plastic side cover. There should be a small one way valve in the hose about half way down the spar - you will have to remove the hose from this valve in order to blow air into the tank. Remove the line above the valve, make sure the fuel cap is tightly on the tank, put air pressure on the vent hose (even blowing with you lungs should be enough to move the fuel) and watch the drains and see if you can move gas thru it. If the drain shows gas moving - close the drains and fill the bowls and try to start it.. I traveled a long ways by blowing into my tank like this one time (lost a fuel pump out in the desert) and it worked great.. Might give it a try!!

Edited December 28, 2015 by cowpuc

[JMNTX]

When I take the fuel line loose from the carb intake or in front of any of the carbs and turn on the key gas will just keep pumping until I turn off the key. I'm getting gas to the carbs but none out of the bowls?

[Venturous Randy]

The pump only runs for two seconds. Turning it off and on after that with no results. Wait about an hour then turn the key it cycles for about two seconds after that nothing also the bowl drain screws are backed out but no fuel comes out after the first little bit?

 

1st of all, are you sure that you are loosening the correct bowl drain screws and not the air mixture screws? Another thing when trying to fill the carbs is to turn the ignition switch to on and cycle the KILL switch instead of the ignition switch. This also makes it easier to hear the pump if you have several keys.

To me, it seems very unlikely that all four carbs would get blocked at the same time. On my 83, if the bike has set for a long time, I will have to cycle the kill switch 15 or 20 times until the carbs fill up. Another thing about many of these bikes is to not give it any throttle while cranking. When mine gets a little cranky(no pun intended), I will choke to full choke and while cranking slowly move to off choke. If it does not start, it will usually always hit a couple times.

Randy

[KISA]

Check pressure sensor

[cowpuc]

Hi Johnny, nice chatting with you a second ago, pleasure to meet you for sure!!

Here is that short video I was telling you about, I know it is a mute subject now but thought you might get a kick out of it anyway.

 

Here is the only step by step on the carb tear down I could find in our VR Tech section, doesnt appear to have any pics but at least its something.

http://www.venturerider.org/forum/showthread.php?54-Carb-Overhaul-on-1st-Gen

 

And this is the article I was telling you about concerning float levels, this one contains some pics so you can see what your gonna find once you get into the carbs. Lots of pertinent info here.

http://www.venturerider.org/forum/showthread.php?66468-Float-levels

 

Hope this all helps out in some small way my friend!!

Puc

[syscrusher]

So what's the trouble after all?

[JMNTX]

got it running thanks everybody. now figure out what's going on with the blinkers. they're buzzing instead of blinking

[Marcarl]

got it running thanks everybody. now figure out what's going on with the blinkers. they're buzzing instead of blinking

 

Low voltage on your battery?

[JMNTX]

LED for front park blink no problem but not for the rear. I had to use regular 1156 bulbs it's OK no more buzzing thx y'all

[cowpuc]

OUTSTANDING JOHNNY:thumbsup:!!!!!!!!!!!! :clap2::clap2::dancefool::dancefool::dancefool:

 

She hitting on all four?

[NewbeeMC9]

got it running thanks everybody. ........

 

 

So what did you end up doing? It's good to hear the continuation of the saga. Plus we all get to learn from it.

[Chaharly]

I'd love to hear how you fixed it as well.

[JMNTX]

I guess there must be something in the tank. I put it back together it started good idled fine without the choke. Took it out for a test ride around the block all good when I got it out on the interstate it ran good for about two miles then started missing. It would completely stall out let it set for a while it would start with the choke and would eventually run good without the choke for about 2 mins then it would do it all over again.

[JMNTX]

ok I took the carbs off and I just left them together at first I just tipped them on end in a bucket with 6 pints of seafoam. I'd flip them occasionally but left them soaking all day. When I installed same deal. Its sounds like I'm not getting enough gas. So I separate and find one float needle stuck and two have small holes in the deceleration diaphragms. None of the jets were clogged there was a little evidence of some time in the past some crud had formed in the bottom of one. So I don't know enough about carbs to know if what I've found is causing the problem. I buy four old carbs with cables from the salvage shop. Mr. Motorcycle they have very helpful, salvaged the parts I needed and it started running refer to previous post.....Now when I got off last night I finally took off the sending unit and looked in the tank. I couldn't tell you why I haven't until now but there I found a piece if light blue putty about a four inch semicircle hovering half submerged in the tank wtf. Cross your fingers, I'll let you know how the next test ride goes. Maybe I need to polish the gremlin bell someone put on it. Pay some homage or something

[NewbeeMC9]

Maybe that was it, the puddy would get sucked on to the inlet and give you outta fuel symptoms, then after sitting it would float off and you could get it running. I've heard of a similar situation on a beetle tdi, it ended up having a rubber glove and some leaves in the tank. It has a fill hole pointing up also. interesting. Thanks for filling us in.

[JMNTX]

what and where is the pressure sensor

[JMNTX]

I'm stumped I still can't get to run right. It starts right away, idles smooth without the choke. The first turn of the throttle once it's warm it will rev right up but the second time it wants to stutter, stall and will eventually die if keep the throttle open. If I gradually twist the throttle and don't turn it to far will rev up pretty high before it starts acting up.

[JMNTX]

I guess it's got to be the carbs. Did I read on here somewhere about a place to send them to get them refurbished?

[JMNTX]

Well I took'm off again looked them over checked the two jets I see one on top in the throat and the one inside the float chamber are there anymore I'm not seeing? It will still only rev to 3 grand then it start stauling.

[NewbeeMC9]

Are the carbs synchronized?

 

And thanks for this thread, I'll probably be going thought the same scenario in a month or so.

Edited January 22, 2016 by NewbeeMC9
give thanks :-)