About ready to blow this thing up!!!

I just put my 750 maxim back together after hhaving carb and electric problems. Found what I thought was the electric problem. There were a couple of wires that looked as if they were cut, so I spliced them back together and hooked everything back up. The wires were coming from the kickstand switch i think. When i went to start it, it let off a nice backfire, and then started better than it ever has. I went for a test run and it worked okay. Felt like it might have had water in the fuel. So i drained the fuel and put new gas in it and it worked okay. I get to work and park it. That night, I went to go home, and there is gas leaking from the petcock and when i started it, only the #3 piston was firing. I had to leave it there overnight and now it won't start at all. What do I do? I am about ready to give up on this thing and keep walking to work.......

 

If you had water in the gas did you drain the bowls too? What made you think you had water? Hesitation can be a mixture issue too.

Second when you cleaned the carbs I assume you set the mixture screws to about 3 turns out as a starting point? have you done any tuning to get the mix right?

You need to fix the petcock leak - that can be dangerous.

Pull the plugs and look for fowling. If you are running too rich they can fowl easily and that can cause them not to fire.

Once you have eliminated the starting issues and fixed the petcock you can get into some serious tuning.

 

is the petcock in the prime position? that can cause some issues. id say clean the carbs, check the valve clearances, balance and sync your carbs, then nail down the proper idle mixture. check spark and air while you're at it. does the bike try to turn over when you hit the starter, or does it just sit there not doing anything? did you check your fuses? have you done a compression test? if the bike wont start, get a buddy to help you. one of you push the bike in fourth with the clutch in, the other hold the compression gauge. once you have some speed, let out the clutch and check compression. do this with all four cylinders.

note: im a beginner, so this is about the extent of the advice i can give you. listen to bill, he knows his stuff.

 

This problem sounds like your Petcock leaks, leaks-by and flooded you.

There are two schools of thought on the Petcock.
Rebuild using Kit.
Buy a New Petcock.

I used to recommend buying the Kit.
I think buying a Brand New Petcock is cost effective.
The new ones all seem to last 20-25 years or so.

 

when i get back in town, I'm in Mississippi for a funeral, I rebuilt the petcock, cause the valve thing on the inside was ripped and it kept dumping fuel out of it. When I went to put it back on, one of the felt looking gaskets for the mounting screws torn off. That's where it looks like it's coming from. How do you set the carbs? I didn't do anything like that when i cleaned them. Also, what octane gas do ya'll use in yours? Thanks for the help.

 

I run 87 in mine with no issues. For you leaking screw get some GOOP it's a fuel proof RTV like sealer. That will work until you get a new washer.

Carb adjustment will depend on what you did to clean them. How far did you break them down? If you removed the mixture screws you need to be sure the o ring and washer are in correctly (washer above oring) and that the screws are about 3 turns out to start.

Main thing will be to look the plugs. If they are black you are running too rich. We can go from there.

I am assuming you only have an external fuel leak. If your petcock leaks then as Rick said you could be flooded.

 

Do not give up when you get this thing running well you will be so happy. I remember telling my friend "this damn bike has one more chance before I give up on it". Ten more carb removals and a petcock replacement later, It is a dream to ride. I love the instant warm up with very little choke. I am used to my cb750 that warms up some were along the ride.

It will be worth it in the long run.

Ciro

 

when i cleaned the carbs, i took the bowls, top caps, floats and needles, and jets out. I replaced the float needles and the brass thing it goes into, i forget what it is called. Can you describe what exactly i am supposed to turn 3 times to start? I am not sure what ya'll are talking about.

 

You need to search for, and read SEVERAL of the longer carb cleaning threads. There are MANY things to sort out while inside the carbs.
Plan on spending 2 hours reading about all the tricks, and problems.

The "pilot" or "idle mix" screw is initially set-up 3 turns out. It may be covered by a tiny silver plug. Use a snugly fitting flat blade screwdriver.

There are 4 spots on each carb that you should run a fine wire thru, with carb cleaner to verify that hidden jets and passages are clear !!!

 

You need to accurately adjust the:

Pilot AIR Screw. More commonly referred to as Pilot Mixture Screw.
Some Manuals indicate the feature is Factory Preset and non-adjustable.
Not true.
We learn to adjust them in here.
That, ... we call "Tweaking" ... or, ... "Dialing-In"

This adjustment controls the AIR being drawn into the Engine when the Throttles are closed.
The Air Passage feeding this Adjustable Screw intersects with a FUEL Passage fed by the Pilot Fuel Jet.
As this Screw is adjusted ... up or down ... the Air Stream it controls will siphon more or less fuel from the Pilot Fuel Jet Passage.

Hence it gets its Name: "Pilot Mixture Screw"

Find it here:

 

Timetoride is right - a lot of things to learn but well worthit.

Clean enrichment circuit
http://www.xjbikes.com/Forums/viewtopic/t=8918.html

Clean carbs
http://www.xjbikes.com/Forums/viewtopic/t=2908.html

Carb Sync
http://www.xjbikes.com/Forums/viewtopic/t=2132.html

Bench sync
http://www.xjbikes.com/Forums/viewtopic/t=6366.html

 

It can be discouraging sometimes to be very close to getting Dialed-in but have an obstacle to overcome before finishing-up.
You always hope it is something easy to adjust. But, sometimes its not what we think and it takes time to find it.

Don't try to rush it. Do one thing at a time so you know what you have done if you get results you are not looking for.
Eventually everything coming together and the bike purring like a kitten will be the reward for sticking with it now.

 

I know what screw your talking about now. the manual told me not to touch it, so I didn't. I guess i'm going to have to pull the carbs again? I gonna try to adjust them w/o doing that. One other question that is a little off subject. When this thing gets running good, do ya'll think that I would be able to ride it from south carolina to southern arizona? Right now this is my only means of transportation, and I have to go back to school for a new MOS at the end of march. Have any of you ridden your XJ that far before?



Oh and thanks for the pic of the screw, that is just what I needed.

 

You want to adjust the mixture on the bike. Search on plug chops and reading plugs to get dialed in.

Lots of folks have taken very long trips on their XJs. No reason you can't.