T3 only turns over with full charge

[caricamento]

Hi all,

I bought a used 1976 T3 in September, and about two months later started having charging issues. I could start it a few times after a trickle charge, but after the third or fourth try I realized that it just wasn't charging the battery - which would be down to about 25%. So I would trickle charge it overnight every time I wanted to go for a ride. (Got the battery checked out last night - it's fine, at 330 cold cranks out of 340 after an overnight charge). In November I began checking everything I could with my standard garage tools, multimeter etc. Couldn't locate the problem. In December I took it to my mechanic, who said he had a hell of a time finding the problem and re-wired it up with a new combined Regulator/Rectifier. Now it charges above 2500 RPM, and as far as I can tell it's actually charging the battery like it should because it's almost full when I put it on the charger now.

The second piece to this puzzle is the flywheel and starter motor. When I bought the bike, I was warned that the flywheel was worn from years of riding, and that I'd have to occasionally shift into first while holding the clutch to get it to catch.. When I got the bike back from shop, I took the starter out and gave it a good emery scoring and a cleanout and all that, and I'm confident that I put it back together correctly. Now I've noticed that the starter motor slips more often but it is also much more vigorous when it does - I get a lot of rotation from it.

So here's the problem: when the starter engages, it loses power very quickly. The engine resistance is too much for the motor - and there should be very little anyway of whether I'm in neutral or holding the clutch in first. I'm positive that I'm not flooding the engine, because if I stop into the store for a minute and start her up again without using the throttle I still have this problem. I cleaned the spark plugs yesterday, and when she runs she runs fine. It's just the starting that gets me.

Thanks for your help-------

Alex

Will try to get a video of this if I can.

 

[john zibell]

Alex,

The Bosh starters draw allot of current. The older they get, the more they may draw. For this reason, Guzzi started using the Valeo starter. It provides the same or more starting torque, with less draw. If you don't like the Valeo, try one of these:

http://www.motoelekt.com/guzzistarter.htm

If the ring gear is so warn the starter doesn't engage properly and binds, you may need to replace it.

 

[jr1967]

Try if the situation improves with a jumper cable from the neg pole of the battery to one of the mounting bolts of the starter motor. If yes make up a new longer cable to the mounting bolt instead of the original to the top of the gearcase. If not check the positive battery cable to the starter motor for any corrosion of the connections. If thats all clean and ok, you could do the cheap fix of new bearing bushings in the starter motor and maybe a new solenoid. If you're happy to lug around the big 28-32A battery the bosch starter should get you started especially with a T3. Valeo's are nice though....

 

[mike wilson]

Also check that it does not have the cockeyed wiring depicted here.
https://www.guzzitech.com/SmallBlockRelay-PHayes.html

Correcting this was the best 30 minutes (unscheduled/unplanned) preventive maintenance that I have ever done on a Guzzi. Complete absence of starting problems ever since.

 

[guzzibob]

mike wilson wrote:

Also check that it does not have the cockeyed wiring depicted here.
https://www.guzzitech.com/SmallBlockRelay-PHayes.html

Note that above reference is titled "small block"-and T3 is most assuredly big block, so not sure how much it applies. Also, battery testing good or no-how old is it? Not uncommon for bad batteries to test "good". My T3 has been & still is about as easy starting a Guzzi as there is, still with the original Bosch starter after over 150k miles-albeit lots but by no means all of them long distance with relatively little starting action per mile. Any time it's been a problem to start, it's either been the charging system (usually the rotor), seemingly eliminated here, or the battery. I always have used old style open cell lead acid Interstate SP-30R's, which are cheap (under $60 last time), easy to find, hard to kill (in part becasue you CAN put water in them), & very happy to work with old style charging systems like the one in our T3-which new style batteries sometimes are not. The ones in my two older Tontis (T3 & big valve 1000S) are now 4 years old, & still working just fine. The Valeo starter (which I have on my 1000S) is certainly a way superior performer to the Bosch-much lighter & spins much faster-in fact, spins my much harder to turn S obviously faster than the Bosch turns the T3, & I gather is a direct bolt on. Kind of overkill for a small valve motor like the T3, & obviously not "authentic"-if you care-but if it turns out your Bosch is toast anyway....

 

[caricamento]

All - thanks for the suggestions. John was right. I bought a new Valeo starter and installed it. She now starts up without hesitation. Those permanent magnets really do the trick.