Fuel not flowing freely

[doodsaibot]

So, I noticed my bike would not start up today. I rode it about 24 miles or so a couple days before with no issues. In fact, it ran better than ever and I had a blast since I had cleaned the carbs a couple weeks before. Anyway, I disconnected the fuel line (with filter still attached to the fuel line) and switched to PRI. Fuel flowed freely threw the line. Switched back to ON and cleared any gas from the line. I reconnected to the carburetor and switched to PRI but no gas flowed through the see through filter. The filter is only a couple of weeks old. I am puzzled. Would there be air trapped inside the carbs that is not allowing me to prime the carbs? It's strange that the PRI function works when disconnected from the carb but does not when connected to the carb. When I try starting the bike again it pulls gas through the filter but the bike will not start. At best it will get up to 900 - 1000 rpms and lay there for a minute until it dies on its own. Just 2 weeks ago I cleaned the carbs myself and an acquaintance of mine (who is a mechanic) cleaned them afterwards and gave them the OK. I be puzzled....



EDIT: We did have a little bit of rain here recently, do you think some moisture snuck into the carbs or somewhere else? I only have a bike cover for my ride. No garage.

 

[Lou Ranger]

A long shot, but is there any chance you could have installed the in-line filter backwards and then dislodged detritus from the tank on your ride?
A backwards filter still flows, but any detritus is trapped on the inside of the screen where you can't see it building up.

Not very likely, I know - so it's probably something else, and I'm sorry, but I don't know anything about carbs. Others do though and they will chime in.

 

[doodsaibot]

I realized the hose Behind the fuel line had become disconnected. Does fuel travel trough this hose or just air? Either way, I am going to take off the carb and drain them out,reconnect everything and she what she does. She may have pulled in some moist air. No telling when that line popped off. The little pinch clips are old and don't hold a good seal.

 

[Greasey Fingers]

Thats the vacuum line, the other end attaches to the R/H carb boot right?

 

[doodsaibot]

it is a 3 inch piece of hose. it is on the left hand side of the bike, left hand carb holder. it goes from the back of the petcock valve to the left hand carb holder. 83 maxim. I reconnected it and the engine is having a hard time turning over. it barely starts up. if it decides to start, the rpms drag around 900-1000 but it sounds like it is struggling. the throttle response it sluggish.

 

[doodsaibot]

After further investigation, I noticed the left drain plug on the carb is rotted so I am not able to loosen it with a screw driver. I drained the right side though and they bike is still struggling to start up and maintain an idle. Also noticed that the right exhaust is a bit more "thumpy" sounding than the left side.

 

[xschris]

How do the spark plugs look? Have you check the oil in the bike and smell for gas in it.

 

[doodsaibot]

I changed the spark plugs after this problem arose. The oil does not smell of gas. I just checked the spark plugs again and the right one is already turning black. The left one is clean looking.

 

[xschris]

If it is turning black it is running too rich.

 

[doodsaibot]

that's what i am thinking right now. It's odd though that it is only on one side.

 

[xschris]

Have you synced the carbs with a manometer? You may also want to check that all the parts in the carbs where assembled in the correct order after cleaning them (and adjusted to spec).

 

[doodsaibot]

I'll look into it

 

[doodsaibot]

well, now I can't get the bike started. I may have to just hold off for a while til i can actually get it started.

 

[doodsaibot]

So, I was close about the fuel not flowing properly. I looked in the gas tank and saw a chunk of rust flakes collected at the upper corner of the tank. The gas was also a dark yellow color and very hard to see through. I believe the flakes were contaminating the gas and basically choking off the operation of the bike. My maxim did not like that rusty gas at all.

I pulled the petcock and there were flakes all over that vertical screen. I removed the tank (before I removed the petcock) and emptied it out. I used the Purple Power De-Ruster and rinsed that out real well with gas. I figured it was empty and clean enough but I could still see a bit of liquid in there so decided to blow it out with compressed air to be sure..... more tobacco juice liquid came bellowing out from God knows where! I refilled the tank with fresh gas and some Berryman's and fired her up....

The ole maxim ran great! I looked inside the tank again and it was crystal clear. Good thing I put that fuel filter on after I bought this thing or else my problems would have been way worse. Note to self; if you ever buy a 30 year old bike, check the inside of the gas tank! Hope this helps someone else that may be having a similar issue. Thanks for the help, bros.

 

[xschris]

Cleaning the gas tank and putting new fuel in should be one of the first things to do with an old bike

 

[doodsaibot]

Well, after fixin up the ole maxim the other day I rode it for a good 38 miles or so around town. It ran superbly if I may say so myself. Took off from the line quite well and sang those 7k RPMs quite sweetly. In between that nice ride I took a couple stops to meet some friends here and there and when I left their place it cranked back up no problem.
So, I went to start her up for a nice evening jaunt today and *crank crank crank*.......*crank crank crank*.......had to give it some throttle while starting it to get it to idle. The idle died shortly after. It seems as though the old problem has returned? This time I am left scratchin my head. Any thoughts?

 

[xschris]

I would say it's time to clean the carbs Make sure there is gas flowing from the petcock and in the carbs.

 

[doodsaibot]

That's what I am thinking. I checked the petcock function (independent from the carb) and it flows when set to PRI and is sealed tight when in the on or reserve position so the petcock is OK. I guess it's time for me to roll up my sleeves and show that carb who is the boss around here.