Won't start in the morning, fires right up in the afternoon!

Hello all,
I just bought an '81 xj550 Maxim. Seems to be in pretty good shape overall, but it has a unique, uh, feature. In the morning it just won't start. It has a new battery, turns over strong for as long as I ask it to, but doesn't fire up. After it sits for a while during the day it will suddenly fire right up and run great. It almost seems like warming up in the sun somehow makes it able to start, but what the heck do I know?

Any ideas?

Thanks!

 

Re: Won't start in the morning, fires right up in the aftern

so, its not a morning person...

take it out late at night and itll be the life of the party!

 

Re: Won't start in the morning, fires right up in the aftern

There you go, problem solved! :lol:

 

Not really, you have to clean the carbs, paying particular attention to the enrichment components.

 

Probably true.

Are you USING the "choke" (enrichment circuit?) If so, then Wiz's diagnosis is spot on.

 

I've tried it in the morning with the choke and without. Every time it's the same. I wait until noon or so and it's ready to go. I suspected that "clean the carbs" might be the answer. Why is it that it's no-go in the morning and fine a bit later?
Thanks for answers!

 

Because you got a bunch of gas (although not enough for when it's cold) into the intake tract; then when you went back after it was warm, it didn't need as much fuel AND it already had a "snootful" of gas ready to light up.

My 550s always light easier in the warm of midday than they do in the chill of the morning; and I DON'T need to clean my carbs.

You do; plus you have a whole BUNCH of other stuff to worry about. Lets start with the brakes. READ THIS: http://xjbikes.com/Forums/viewtopic/t=15874.html and stop riding the bike until you've checked; you don't want to wreck.

Now, I don't want to scare you or anything, but the FRONT BRAKES probably need attention as well.

A 30-year old bike IS NOT the same as an '82 Chevy. Your Maxim can KILL YOU, and although that's always possible with any automobile, the chances are much less. If an '82 Cavalier dies, you coast over to the side and get on the cellphone.

Here's what you REALLY need to do to make the bike SAFE and RELIABLE; the problems you're experiencing right now are the "tip of the iceberg" the bike is trying to warn you all you need to do is listen.

Get busy (and I'm not kidding

- check tires, condition, and date codes.

- inspect wheel rims for damage or excessive runout.

- check front brake pads.

- inspect disc brake calipers for damage, wear (thickness), or excessive warpage/runout.

- VISUALLY check rear brake shoes for wear/delamination; adjust rear brake pedal linkage. This is very important. Delamination is common, the only way to detect it is to SEE it. I already gave you the link, above.

- inspect/lube/adjust/replace final drive chain and sprockets. Keep an eye on the chain. If it "bleeds red" when being lubed and won't hold adjustment, it's rusted internally and will need to be replaced. Always replace both sprockets with a chain.

- check and adjust if needed operation of front and rear brake light switches.

- replace rubber brake hoses (check the mfg date stamped in them). Originals rated to last FOUR YEARS. How old are yours?

- unless known to be otherwise, plan on rebuilding the brake master cylinder and caliper(s).

- check and clean/replace the air filter element.

- change all fluids: fork oil, engine oil, and brake fluid.

- check and repair any engine or drivetrain/suspension fluid leaks.

NOTE: almost any original oil seal or engine case gasket will need to be replaced when its cover is removed for the first time.

- check and adjust/lubricate/replace steering head bearings.

- check and adjust/lubricate/control cables and speedometer and tachometer (if applicable) drive cables..

- check and adjust/replace rear shock absorbers.

- electrical system inspection, replace fusebox and most probably alternator brushes.

- check battery condition; replenish fluid (distilled water only!).

- clean the battery terminals.

- check all lights for proper operation and brightness (headlight, tail/brake light, turn signals, dash illumination).

- check horns for proper operation and loudness.

- check stator resistance.

- check rotor resistance.

- check battery.

- check coil primary, secondary, plug caps resistance.

- check engine cylinder compression; record your findings.

- check and adjust camchain tensioner.

- check and adjust valve clearances; record your findings.

- drain carbs, check for foreign matter in bowls, install in-line fuel filter.

- check function/operation of fuel petcock; correct any leaks and/or rebuild the petcock if indicated.

After all that (and having corrected anything that needed attention along the way,)

-Install a new set of properly gapped NGK D8EA spark plugs, and with clean and synchronized carbs, a fully charged battery and clean air filter it'll fire up cold or warm, every time.

Honest.

 

Thank you so much! I will absolutely print out your advice and use it as a checklist to get it safe and sound. I very much appreciate the detailed response.

 

No sweat. You'll need a service manual. The Clymer is OK but has misinformation, the factory manual better but with gaps. Best bet for a 550 is both.

Lots of good stuff in "FAQ Suggestions" on this site; and we're here to help if you get stuck. If you're serious about this, there's nothing better than stylin' around on a shiny new 30-YO bike. Check my gallery. And this post: http://xjbikes.com/Forums/viewtopic/t=31614.html (He has a Maxim.)

And ask questions. Nobody ever gets "flamed" for asking questions (just for ignoring advice.)

 

Re: Won't start in the morning, fires right up in the aftern

In getting my 750 running I had 2 different starting problems. One was that despite a brand new battery, sometimes the starter would just cliick when I hit the button. The other was that sometimes I would crank and crank to get it running--in my case, it would eventually start, but it might take 30 seconds of total cranking (in 5-10 second bursts). This was after having my carbs cleaned and synched by a local shop.

To fix the clicking starter, I pulled the starter motor, hosed out the gunk with electrical parts cleaner and sanded the commutator.

The reason I'm even mentioning cleaning up the starter is that it also turned out to be the solution to the other problem--from then on, the bike almost always starts within a second or two.

 

Update... I'm still in process with all of Fitz's recommendations. Brakes and hoses are good, wheels and tires are good, various other bullet points are in progress with parts on the way. I also pulled the starter and cleaned it, but had the same starting issue. Until I have the time to pull the carbs and clean them (the right way) I have had stellar luck with warming the carbs with a $13 heat gun from Harbor Freight. I just hold it about 10-12" away from the carbs for about 5 minutes before the first start of the day and it fires up right away each morning. Starts fine for the rest of the day. It's clearly a stop-gap "fix", but I thought I'd share that it has worked every time. Of course, I'm in Southern California so the amount of "warm time" could vary greatly for those in colder climates. Again, thanks for the responses and the list of things to check on the bike. I'll keep plugging away.The knowledge on this site is invaluable!

 

I live in the So Cal area & ride mine everyday that the weather is not nasty. After complete carb tune & total starter rebuild. Just a blanket cover at night & she fires every time on first or second quick burst on starter button. Also helped to repair my "headlight on" relay. (More cold crank amps).