Starting Problem - only just turns over but starts every time (so far)

[pjv]

Hey All - first post, new member, returning to the FJ12 fold after approx 20 year absence and change of continent (originally from UK). Sorry if this post is redundant, but i have searched, honest.

I just bought a little bit run down 89 FJ12, 32,000 miles, with some dubious carb/air/exhaust mods. I paid $1400 for the bike and $800 to have the carbs rebuilt, jetted properly, oil, front tire etc. The bike now screams, too loud for my liking but i'll de tune it over time, i.e. re fit original air box etc, instead of K&N's, and quieter pipes.

Anyway, the bike starts every time and runs great, the trouble is it only just turns over, there is no "eeeee, bruuuum" when you hit the starter, it barely turns over, but does start, but sound like it's about not to turn over at all, in a flat battery sounding kind of way, click and nothing. I had the battery tested at AutoZone and they said it was fine, 100% charged, 12.8 volts, seemed ok. I actually did try an off the shelf maint free battery that was (after testing) only 50% charged, and that was worse (not surprising though i suppose).

So i'm thinking it's the starter motor? Weak / bad brushes etc? Instead of faffing around with repairing it i was thinking of the after market one on line, only $70 or so, and not too difficult to replace? Haynes manual should arrive in a couple of days, but i love the depth of experience on this board, so any help/tips would be greatly appreciated.

Cheers,
Pat.

[Arnie]

It is easy to just remove the starter motor, open it up, clean out all the old gunged up grease, and clean up the commutator.  Then you re-grease the bushes at each end and re-assemble.
90% + sure your starting problem will be gone.

Arnie

[andyb]

Yup, it's what, two screws and the wire?  Not bad at all to pull it and open it up.

[pjv]

Awesome, now i feel like a wuss for not wanting to have a crack at it. Thanks guys, I'll give it a shot.

[racerrad8]

I have both the two & four brush starter rebuild kits in stock.

As well as new four brush starters.

www.rpmracingca.com

Also when looking at starters online, some of them are only two brush units.

Randy - RPM

[baldy3853]

Hi just to make it easy take your alternator out 1st it definitely makes taking the starter out much easier lol
Baldy

[fj11.5]

I must do things differently, can take the starter out and leave alternator fitted, although having no airbox helps

[baldy3853]

LOL forgot about not having the airbox mine was still standard when I did it and was a rank beginner 
Baldy

[SlowOldGuy]

Try cracking the throttle open slightly when you crank the motor and see if that helps it turn over.

My '85 cranks over fine.  My '93 cranks slowly unless I give it a slight amount of throttle while cranking.  I got a 4-brush conversion kit for the '93, but when I opened it up, it was already a 4-brush unit.  Cleaning and greasing the starter didn't help.  Still have to crack the throttle.

DavidR.

[andyb]

On my 90, after cleaning and lubing things, no throttle crackage was needed. 

Have you done a compression check by chance on your two bikes, David?  I'm wondering if the difference is more effort to turn over on the later one or something.  That's something that I don't believe  that I did before tearing my motor down, unfortunately.  

[SlowOldGuy]

Haven't done a compression test lately, but the '85 has a Wiseco 1188 (10.25:1) kit and new set of SS valves.  It runs strong!

The '93 is all stock.  Compression related components on the '85 have about half the miles on them compared to the '93.

It would probably be quicker to just swap starters.  :-)

DavidR.

[andyb]

Didn't know if it was a strong motor problem or a weak starter problem.

[pjv]

It is easy to just remove the starter motor, open it up, clean out all the old gunged up grease, and clean up the commutator.  Then you re-grease the bushes at each end and re-assemble.
90% + sure your starting problem will be gone.

Arnie

Arnie - I owe you a pint.
I had a quick look at it, the hardest part was getting it out, it would not come out through the frame as per the Haynes picture, had to pull off two K&N's and lift it up and out.
I could see that only the tips of the curved faces of the brushes were touching the commutator, hence the weak turnover (only a 2 brush unit too). I took the plate off and washed it and the brushes in WD40 (sorry, all I had), the brushes were longer than the 4.5mm minimum Haynes said they should be. Re assembled and now it works fine, turns over really well. Next decision is whether to replace the brushes or the whole thing as a long term fix.

Thanks everyone for the tips, great community here. I'm getting some nice goodies from rpmracing too.

Pat.