'82 Maxim won't start

When I received my XJ650J with a weak battery, I boosted it safely (+ to +, chassis to chassis) from my car and it started right up in less than a second and ran perfectly. Warmed, it responded to throttle well and everything was OK. This morning, did the same thing and while it cranked like crazy, there seemed to be no fire. Gas is OK but it will not fire up. Stand up, switches on, in neutral, lights work, etc.

Went back to it this afternoon and there is now nothing - no lights, no cranking, no nothing. What have I done, or not done? Fuses look fine - are we looking at an electronics problem? Could the boost have fried something?

 

Check your fusebox - under the seat. The "MAIN" fuse probably has a bad connection. You'll be better off in the long run replacing the fuse box completely. It's only a 4-circuit panel.

 

Hard to say, but it sure sounds like you have some sort of electrical issue. Might be multiple problems. I would first worry about getting it cranking. Battery cables good (particularly the ground)? You will have to get out the multimeter and see where you have power and where you don't. I'd check at the fuse panel, the starter and the solenoid first. I bet this is something simple.

Then figure out why it isn't firing. Lack of fuel? Spark? No way to know without running some tests. Pull a plug and ground it to the head. See if it's sparking. If so, drain the carbs and see if they have fuel in them.

Should be enough to get you started.

Greg

 

Weirdness continues - boosted it again everything worked OK and it took quite a few cranks to get it running. Started and ran like a cold motor and after it died, restarted well. Ran very high idle on the choke and when I cut it back it died and refused to restart. Seems like the electrical us OK, gets gas and spark. Previous owner had it out for a 200km trip the day before I picked it up and it started and ran well then. Any more suggestions as to why she just doesn't fire up? Does the YICS system have a play in this? As you can tell, I am a true newbie to the Bike World and obviously do not know what I am in for.

 

THe YICS (to my understanding) just helps to balance your carbs (ima newb too, though). If you can get it started (choked even), then you do not have an electrical problem. How long did you let it warm up choked until you unchoked it? Even w/a warm (88 degree) day, I have to choke mine initially for a few minutes, and I scale it back.

You need to go buy a battery for that bike. They are like $30 at a batteries plus store. The idle working funny tells me it needs to be tuned up, possibly, or that you have dirty carbs. I would check both places first. Also (make sure you aren't doing this); the petcock for the gas has three settings: on, pri, and res. Make sure you are set to on and not pri and pri is for only when you have flushed your carbs and need to refill them. Use res if you are almost out of gas.

 

Yeah, I figured that I would have to do carb work. Looking at all the posts on XJ Bikes, that is a very common story. Just hoping not to, because of the complexity, delicate balancing act, time factor and cost. Oh well, I bought a bike to have a hobby - looks like a lot of that hobby will be learning, fixing and investing time. Just hope it will be worth it. Thanks for the replies...I have found the long dissertation on carb rebuilding on this site and I am grateful that one of our XJ owners took the time and effort to create it.

 

Carb cleaning ain't that bad unless the previous owner screwed up anything in the carbs which I think is my case. I have opened up all the carbs but oh well good luck matey.

 

What's the ticket - manual teardown and rebuild, or seafoam, or alternative suggestions?

 

Take off the seat.

Turn ON the Ignition.
Set the Kill Switch to Run.

Take your Propane Torch ... don't light it ... but, put some of that Propane right straight into the rubber Intake Port.

Start 'er up.
If it runs on the Propane ...
You have to investigate why it isn't getting Gas through the Carbs.

This ... "Ran fine one minute; don't the next" is becoming all too common with the way Gasoline is being distributed and stored these days.

The arrow is pointing at the Carbs.

 

Being winter here in Oz and with mornings around the 5 to 7degC mark the ol' 900 has it's moments some mornings. What I have found and others will probably support is that if the battery isn't 100% AOK then starting and getting it to tick over initially when cold will be a problem.

In the mornings I put the battery on the charger for about an hour while I get ready for work. Doing this, on most mornings she fires up with some choke fairly easily. The theory is that the starter drains power from the battery while it is cranking over, but, the battery also supplies voltage to the TCI box to give spark to the plugs - reduced battery power could mean reduced spark intensity. Add to that starting technique (full or half choke, throttle completely closed or slightly open) and you may have a problem turning it over and getting it to idle.

Other suggestions re fuse box and connections are well worth checking to make sure all is well.

If I don't place the charger on the battery on these cold mornings it just gets a little more uncertain when it will actually start to run. I can tell the difference - one hour of charging just gives that cold battery/engine a bit more help.
All this of course presumes that fuel into the carbs/engine is at least getting through is some form, albeit with an out of tune engine.

Regarding dirty carbs, I can't help feel with the number of photos and posts that clean fuel (or absence of) is an issue in the states - my old XJ's carbs were pretty well OK when I pulled them apart last year.

 

Looking for a little more direction - I will replace the battery but in the meantime if I have a good source of power and the bike can start occasionally, I am likely looking at carb work. Is the best use of time and energy directed to a manual rebuild of the carbs or a system cleaning with seafoam? Or are there better options I should explore?

 

For the carbs, you first have to find out what kind of carbs you have. Look at the right side of the carbs and you will see a name; either Mikuni or Hitachi. If you have Hitachi carbs, well, lucky you, Rick has written a how-to tutorial about it. If you have Mikuni (such as what I have), well, the tutorial will help you get them opened up, but there are subtle differences. One major difference is there is a heat shield (a big piece of metal) on the bottom of the carbs that you have to remove to get to the float bowls.

Just an example story for you; When I got my bike, I knew pretty much nothing about engines. I knew basic things like, what a spark plug was, what the carbs were, what the engine block was, but that was about it. These boards here are filled with A LOT of very smart ppl who have the patience to help you through this. There is not a dumb question to ask, so ask them all!

Since getting my bike less than a month ago, I have cleaned out my carbs, and its not as bad as you think. The term "rebuild" makes it sound hard, but in reality, its not that bad at all. Its time consuming, but not really that hard. Working on this bike has helped me to understand engines much greater than I did before so. For instance, I was reading an online page where a guy rebuilt a '64 scooter, and when he got to the carburetor, even though it wasn't the same like mine, all the parts are still there (just arranged differently). I even took my lawn mower apart today and cleaned it up to help it run better.

If I can do this, you can too! Don't give up... Hope that helps.

 

How long did the bike "Sit"?

More than a few weeks?
Do the carbs!

Want the bike to run Great!
Do the Carbs!

 

OK, OK, I'll do the carbs! The message I am hearing is - shortcuts are for sissies. Thanks for the input and the link.

 

One last question - what will I need for materials? Carb cleaner, 4 rebuild kits and what all else? I would like to be prepared in one trip and eliminate as much running around as possible. And how many days are we talking for a newbie to do this job? By the way, the bike did not sit at all as the previous owner had it out 2 weeks ago. Thanks for all the help guys...I'll let you know how the work turns out.

 

Also check your carb boots (rubber intakes) for cracks or holes. If they are sucking in air your bike will do exactly what it is doing now. It's not uncommon for these boots to dry out. If there border line replace them when you tear you carbs out because they will be out anyway.

 

Hey PJ:

Can you fill-out your "Signature" feature with thumbs on your bike.
I really helps-out being able to look at the screen and have this info.

________________________________________________
Year - Model - Total Miles - Stock or Mods - Main Issue

Bite the Bullet and slap some new Float Valves and Seats in her.
Everything else can stand the test of time (well ... almost!)

 

Pic is uploaded and should be visible. Stock '82 650 with 88,000km or about 54,000 miles, bought from the original owner.

 

Before I start stripping parts, I seem to remember seeing a post about repairing cracked carb boots with solvent and silicone. Is this a proper repair? Where is a good supplier of parts here in the Great White North? I have nothing to compare to the local dealer even though he seems reasonable for price.

 

I've been using 5-Minute Epoxy to Repair large cracks and damaged MANIFOLDS. The stuff is easy to use because ... It comes in BLACK and the Epoxy and Hardener are dispensed from side-by-side syringes.

Softer Rubber Parts I use the New "Liquid Electrical Tape."
Works pretty good on Diaphragm Rubbers too,

 

I will give the 5-min epoxy a try. It has been some years since I worked on anything mechanical and that nervousness has me concerned when working with important parts like forks and delicate carbs. I will start pulling it apart Sunday and hopefully handle what comes.

 

On one of the fork pages, there was one smart fellow who welded a 19mm nut on a threaded rod to access the bottom of the fork tube. Sounds like a great idea and as I do not have a wealth of tools, asked a shop to make one up. Is $50 to make the tool worthwhile?

 

50-bucks!!

How about 5-dollars, TOPS!

All you have to do is weld a nut on the end of a rod.
You could get by ... with just putting a few nuts on the rod and tightening them to prevent them from moving.

For 10 or 12-dollars he should weld a 22-mm nut on the other end and you have a Universal tool.

 

OK, I'll ask the dumb question - what's the 22mm nut for?

 

Found the parts cheap - $10 for everything with 2 rods and 4 nuts so I can have 2 tools and a welder pal who will do the work for a beer. Still, I need to know - what's the 22mm nut for?

 

That's so you can flip the tool and rent it to guys with bigger bike's!

The damper on bigger bikes is 22 mm ... (so, you have Both tools on one)

 

Success!!!

It starts at the first pull!!



Thank you!!

 

RickCoMatic - thanks for the help - you are indeed the XJ Master that your reputation describes. Have enjoyed your extra articles and efforts shown in Archives. My bike runs fine in spite of all the fooling around I did, but it seems to run best when cold and on the choke. Running warm near WOT up through the gears brings little fits of hesitation throughout the range. What may I have missed, or what needs a re-look?

 

If you need Choke -- you need more Fuel.

The Main Jets feed the Carbs its Fuel at WOT.
Since you are NOT Pulling enough FUEL at Wide Open.

My first Guess would be Emulsion Tube Metering Ports Clogged.

My second Guess ... Float Height.

And then there's ... Both!

(Don't forget that the Slides need to Open and Drop without a problem; too.
If you have Diaphragm Pistons Sticking -- Un-stick 'em)

 

Diaphragm pistons are unstuck and she works like a top...thanks Rick!

 

I have the Mikunis, (but not heat shield). Doesn anyone know of a source for a step by step on their ttear-down? I've read Rick's tutorial, and found it to be very helpful. I also have the yam factory manual. How different are they really from the Hitachis? I'm hoping to clean mine in the next week or so, but am a carb virgin, so to speak (not counting heavy petting and makeouts)

Lovin' this forum. Lots of great info, great environment...Kudos

 

Dude, the carbs are darn near the same. Rick's instructions should see you through with your manual in hand.

 

The Pilot Jets on Mikuni's are Bullet-Type and hard to get out without a SPECIAL TOOL THAT FIT THE SLOT IN THE JET ~~> Perfectly <~~

If you break-off the Slots of a Hitachi Pilot Jet ... You just grab the thing with Locking Pliers and get it out.

If you Break-off the Slot on a Mikuni Pilot Jet ... you got Big Trouble ... they're recessed and small ... you'll be drilling-out a Jet down in a recessed cavity that is smaller in diameter than a Brand New Pencil Eraser.

The Hinge Pins have heads on them like Nails. Only come-out one way.
If its never been out; it's pressed-in and you could break-off a Hinge Pillar-tip and need to do some surgery.

Don't start the job without:
Hand Impact Tool
Main Jet Screwdriver
Pilot Jet Screwdriver
Pilot Mixture Screwdriver.

If the Anti-Tamper Plugs are still in place on Mikuni's ... they are almost 4mm Solid Brass Plug.

Don't drill it.
Dentist it out.
Use a cutting tool and remove as much of the Brass as you can being mindful that -- The Pilot Mixture Screw is practically touching the Bottom of that Plug.

The Emulsion Tube (Nozzle) is slotted and keyed on Mikuni.
The Float Valve Bodies can be "Presses-in -- O-ring type"

Place the SHANK of a perfectly fitting drill bit into the Valve Body before using any kind of Plier to remove the Valve Body.
The shank will prevent the Valve Body from being squeezed "Out-of-round" whem you remove the Valve Body.

 

Thanks for the tips. I'm sure they'll be most helpful.