no start LR cylinder fuel of fuel

[vzuden]

I have 2007 tour deluxe that wouldn't start yesterday when I needed to leave work to head home. The starter would engage but the engine appeared to be locked up. I towed it home and started by pulling the seat and tank to access the plugs. The first one, left rear cyl, had fuel dripping off it. The other 3 were dry. I hit the starter and it blew a bunch of fuel out iog the cylinder. I put the plugs back in and it started and ran fine on the fuel in the carbs.

Earlier in the day yesterday a coworker pointed out fuel dripping from that carb. i always turn the petcock off. Just a habit for many years. Anyway, put it all back together and rode about 20 mlles and everything seems fine. Here's a little history. About 1,000 miles ago my original fuel pump quit. I found in this forum i could replace it with an aftermarket pump from an autoparts store so I installed a Mr Gasket part number 42S. The only other symptom has been some popping from the exhaust at idle. I have Baron 4-2-4 Nasties mufflers. The sound is a "pop....pop.pop. pop......pop" and stops with any amount of throttle applied. Whenever I hear this I add a can of Sea Foam and it seems to correct it.

 

Any ideas why I had a cylindeer full of fuel? Do I need to switch to the factory fuel pump?

[Yammer Dan]

Float sticking. More Sea-Foam

[Gary N.]

Sticky float. I'd do an oil change ASAP. Some of that gas got past the rings into the crank case for sure.

[eusa1]

Very common concern with the poor quality fuel that we have here in Illinois

Replace the needles and clean the seats in the carbs.

They get a corrosion build up on the needle and flood the cylinders with fuel because they stick in the open position.

This will destroy your motor if you ignor it.

Drop your oil and you will see that it is over full and

Smells of gas.

The seafoam can help a bunch, but is not a cure.

I updated style needle with a coating will stop the corrosion and the problem.

Feel free to call me.

[dbikers]

yep, what these guys said. The float for that cylinder stuck open and the cylinder filled full of gasoline (hydro-locked). I don't know the history of your bike (like has it fallen over, have you run sea foam or other fuel cleaner thru it) and im really not sure how it could flood with the petcock off(as you always sut it off) but either the float is just "sticky" or something is holding it open.

somehow you need to verify that the flot is shutting off the fuel when it's up. again, like these guys said change your oil as soon as possible for sure

[1fastbob]

I agree with what the other posters have posted. One additional comment...is it possible that the aftermarket electric fuel pump you are using is of too high pressure for this application and is pushing fuel past the needle and seat in the mentioned cylinder?

[1fastbob]

I agree with what the other posters have posted. One additional comment...is it possible that the aftermarket electric fuel pump you are using is of too high pressure for this application and is pushing fuel past the needle and seat in the mentioned cylinder?

After looking at the specs of the aftermarket fuel pump, I am thinking it is not the problem. Probably you have some debris in the system that is causing the mentioned carb's needle to not seal off the seat properly causing raw gas overflow the carb bowl and to drip or run into the cylinder. Edited June 16, 2013 by 1fastbob

[vzuden]

In regards to the inquiry of whether the bike had tipped over, no it hasn't. It has about 21,000 miles on it with all but 1,800 put on by me. It was 2 years old with 1,800 on it when I purchased it from a private owner 3 years ago. The carbs were full of gunk then and I took it to the dealer for the carb overhaul. I have replaced spark plugs every year and sync'd the carbs and it ran perfectly until this and the fuel pump failure a couple of weeks ago. The popping in the exhaust I mentioned in the original post would be another deviation.

[sldunker]

What may have happened is when you replaced the fuel pump a little bit of dirt fell off one of the hoses and got inside the fuel line. This worked its way to one carb and caused your needle to not seat. I would drain that carb using the drain screw. Do it 2 or 3 times to try and remove any dirt in the bowl. Because you turned your fuel off there should not be much gas in the oil. I would remove oil fill plug and see if you can smell gas fumes in the crankcase. You could also remove oil filter and drain contents into a clean container and see if there is gas in your oil. If you can't see or smell gas in oil you are probably ok not to change oil. If there is any doubt in your mind change oil any way.

[vzuden]

This morning I hit the starter button after sitting all night and it started instantly. I didn't leave it running since I am going to change the oil. Thanks for the advice to those who suggested to change oil. I was so relieved it ran without knocking yesterday the thought never crossed my mind.

Going out to the garage to change the oil and see if I can figure out where the carb drain is located.

[RSTDdog]

This morning I hit the starter button after sitting all night and it started instantly. I didn't leave it running since I am going to change the oil. Thanks for the advice to those who suggested to change oil. I was so relieved it ran without knocking yesterday the thought never crossed my mind.

Going out to the garage to change the oil and see if I can figure out where the carb drain is located.

 

If the dealer that overhauled your carbs installed the bowls correctly you should see the drain screws looking through the V. Right carb drains are visible from the left side through the V and vice versa. Each should be canted inward toward the V to be accessible with a long screwdriver. It is possible to put the carb bowls on the wrong carburetors. They will fit but then you can't access the screws with the carbs installed.

 

Also another place they can leak fuel by is the oring that seals the brass seat for the float valve assembly. That oring is not available separately, at least not from Yamaha. Did they replace the float valve assemblies when they overhauled the carbs? If not cleaning solvents could have damaged that oring. Some things to consider.

[wes0778]

One thing I would add is be careful as hydraulic lock CAN bend a rod which will eventually break and come out through the engine case. One member here can attest to that. It would seem there was not enough fuel in the cylinder to completely lock the engine, but enough to obstruct the piston travel just short of TDC. When the the starter was engaged the engine started but when that piston came to the top it made a heck of a racket. Several of us heard it, but didn't know what it was. Later that day the rod came out. Not Pretty!!!

[vzuden]

I am not sure what they did with the carbs when they had them off. they just said they were full of gunk. That was 2-3 years and 20,000 miles ago. I have been riding the bike everday since I got running on Saturday and it seems to be ok. Probably in the neighborhood of 250 miles so would a rod issue have shown up by now? It seems pretty quiet without any knocking or unusual noises.

 

Since this happened I am really leery whenever I go to start it. I did find the carb drains and opened the drain and let the pump refill the bowl 3 times as was suggested. Its pretty hard to tell if anything came out since the piece of whatever was probably too small to see. I tried catch the fuel as it came out but it went everywhere.

 

Thanks to all of you for sharing your experience and advice. I hope I can eventually get to the point I trust it again

[Guest tx2sturgis]

The way I understand the OEM pump, it has a backflow preventer AND a positive shutoff.

 

Meaning: if it is not operating, fuel CANT flow thru it. So even if a float sticks, you wont find a cylinder and crankcase filled with fuel..only what will flow over from that one carb bowl.

 

The inexpensive aftermarket electric pumps sometimes have a backflow valve, but rarely have a positive shutoff.

 

With the pump you installed, you should ALWAYS turn off the petcock when parked for more than a few minutes, to insure that if the floats stick, you wont hydrolock a cylinder with fuel.

 

Definitely change the oil, and get in the habit of turning the fuel petcock to OFF. Your bike should be fine. Just ride it and have fun.

 

 

 

 

 

 

Edited June 20, 2013 by tx2sturgis

[vzuden]

Brian, that's part of my concern. I am 100% sure, without a doubt, the fuel petcock was off. I have been doing that for 40 years. When the day comes when I get a bike without a fuel shut off I will probably have to add one because I will always be reaching for it.

 

There must have been enough fuel in the lines, fuel filter and pump to fill that cylinder. When I hit the starter button, I did it three times with the same result, it would not turn over. The starter engaged but that was it.

[RSTDdog]

Not sure how you start your bike, but if its similar procedure to me the following scenario is possible. I turn my fuel on, I turn on the key and wait for fuel pump to finish priming (runs for a few seconds and shuts off), then engage the starter. If your float was stuck and the cylinder was just before TDC where intake valve is not quite closed, the prime function of the fuel pump could deliver enough fuel to hydrolock that cylinder (doesn't take much near TDC).

 

I know when the bowls are full and the bike has been running,the prime function doesn't run nearly as long as it does on a cold start, sometimes barely half a second.