Slow cranking starter

[OldButNotDead]

Couple weeks ago I got the "press the starter / get a click /no start" symptom. After a couple of tries, it would fire right up and run fine. My relays are swapped, gel battery relatively new, and charging system operational. Also have dealt with all the interlock wiring...

 

I guessed a bad starter solenoid, so swapped it out for a complete new one from Euromoto Electrics. No change in symptoms. So, I cleaned and dressed the kill and starter switches. No change.

 

So after searching here, I next guessed "starter disintegration" and swapped in a new one. No more clicking. BUT...

 

...now it's turning over way slowly. Partially drained and recharged the battery, with no change. I think this means I've got resistance on the hot end or resistance on the ground end, or a combo of both. Am I missing other likely possibilities? Is there anything I need to do to ensure the new starter is properly grounded? It didn't occur to me during install that I might need to worry about that.

 

I plan voltage drop testing, but thought I'd check in here before I get started (it's getting cold and dark in the garage these days).

 

Unrelated note: if there are any Pynchon fans out there - Moto Guzzi reference in the new novel !

[gstallons]

The most inexpensive tool you can own is a test light. When you have a "no start" condiriion touch the properly grounded test ligh to the start terminal of the starter to see if it lights when you press the starter button. If it lights the problem is the starter or improperly grounded starter. I install shakeproof washers on all ground connections.

If there is no light,start going backwards on the circuit until you get a "light on" condition with the test light.

I assume you have a wiring diagram and are competent enough to use it? If so,you will find your problem.

If you need more help me pm me for my cell and shop #s.

[Dan M]

Voltage drop is the way to go to insure your connections are good. Do it while attempting to crank. It does sound like a weak battery. Check battery voltage while attempting to crank. If it is cranking slow and voltage stays up (above 11) you probably have a bad connection on the large cable or ground. If voltage drops low (9 or less) and it barely cranks you battery is probably weak. High starter amp draw will give the same symptoms but it is unlikely both old and new starters are bad.

[guzzi323]

The most inexpensive tool you can own is a test light. When you have a "no start" condiriion touch the properly grounded test ligh to the start terminal of the starter to see if it lights when you press the starter button. If it lights the problem is the starter or improperly grounded starter. I install shakeproof washers on all ground connections.

If there is no light,start going backwards on the circuit until you get a "light on" condition with the test light.

I assume you have a wiring diagram and are competent enough to use it? If so,you will find your problem.

If you need more help me pm me for my cell and shop #s.

Actually I disagree. I've had many ongoing starter problems on my V11 and after my second Valeo died I bought the expensive Mitsubishi truck starter modified to fit Guzzi's (I thought it was Euro Motoelectrics that sold it but it's not them. I was some similar BMW/Guzzi aftermarket electrical component company.)

That starter lasted about 18 months before I started getting the 'click no start but all relays and the solenoid were firing' symptom.

What was happening was the solenoid was able to slide the plunger down to engage the gear but it wasn't able to consistently press the button and the bottm of it's travel to actually run the starter.

If I ran a jumper from the big, fat lead on the starter to the trigger terminal on the solenoid it would start every time.

I pulled the starter and everything looked good and always worked on the bench. I believe the very long path the trigger signal has to follow (from the starter button through a bunch of switches and relays) was causing enough voltage drop that the solenoid couldn't function properly.

 

I ended up putting a 30 amp relay right at the starter. I trigger it with the trigger wire off the harness and get my nice fat voltage right off the starter terminal.

It's only been a few weeks but it's been perfect since then.

 

That's my experience, I hope others find it helpful.

johnk

[gstallons]

Actually I disagree. I've had many ongoing starter problems on my V11 and after my second Valeo died I bought the expensive Mitsubishi truck starter modified to fit Guzzi's (I thought it was Euro Motoelectrics that sold it but it's not them. I was some similar BMW/Guzzi aftermarket electrical component company.)

That starter lasted about 18 months before I started getting the 'click no start but all relays and the solenoid were firing' symptom.

What was happening was the solenoid was able to slide the plunger down to engage the gear but it wasn't able to consistently press the button and the bottm of it's travel to actually run the starter.

If I ran a jumper from the big, fat lead on the starter to the trigger terminal on the solenoid it would start every time.

I pulled the starter and everything looked good and always worked on the bench. I believe the very long path the trigger signal has to follow (from the starter button through a bunch of switches and relays) was causing enough voltage drop that the solenoid couldn't function properly.

 

I ended up putting a 30 amp relay right at the starter. I trigger it with the trigger wire off the harness and get my nice fat voltage right off the starter terminal.

It's only been a few weeks but it's been perfect since then.

 

That's my experience, I hope others find it helpful.

johnk

 

John,

I don't think I posted anything disagreeable? Do you remember the brand and part # of the Mitsubishi starter.

The relay is the only way to go to cure a lot of current (not voltage) problems. You will make sure you get a good flow of I and E to the starter solenoid. You will save the switch (from burning up) also.

I nstalled a headlamp (headlight switch) relay kit on my 87 SE. This kept me from burning up a $175.00 switch.

[Dan M]

OBND indicated that it is cranking but cranking slowly. That tells me the trigger circuit is functioning. Once the solenoid is pulled (to complete the crank circuit), the trigger has done it's job. The trouble is between the battery, the big wires and the starter at that point.

[Guzzirider]

What voltage is she showing with the engine running? I had this exactly same issue with Helen's V11 Sport tunred out to be a knackered regulator / rectifier which fried the newish battery.

[guzzi323]

John,

I don't think I posted anything disagreeable? Do you remember the brand and part # of the Mitsubishi starter.

The relay is the only way to go to cure a lot of current (not voltage) problems. You will make sure you get a good flow of I and E to the starter solenoid. You will save the switch (from burning up) also.

I nstalled a headlamp (headlight switch) relay kit on my 87 SE. This kept me from burning up a $175.00 switch.

 

I should have stated my (minor) disagreement more clearly. I was objecting to the lines

"If there is no light,start going backwards on the circuit until you get a "light on" condition with the test light.

I assume you have a wiring diagram and are competent enough to use it? If so,you will find your problem."

 

In my case, working with a test light would have told me nothing as it would have indicated all was well everywhere. that's all.

 

The starter I purchased from these people http://www.motoelekt.com/guzzistarter.htm

 

johnk

[OldButNotDead]

Thanks to everyone for your input! I can't answer any of the voltage questions since both multimeters have dead batteries, and dealing with those are first on the todo list.

 

Will post back once I've done some troubleshooting and sorted this out (or not). I better get it done soon, if I'm going to get any more riding in this season...

 

Ciao!

[Murray]

Get your battery load tested the local auto electrician/battery retailer usually do this for free. If that checks out you most likely have a electrical current transmission problem. Nothing on your bike uses as much current (in fairly short bursts) as the starter normally 90amps plus on the average bike. So basically the starter will give troubles before anything else electrical. So the obvious stuff how are you battery terminals free of corrosion clean and tight? Before going any further its worth dripping the earth lead off the battery (saves arc welding antics). Check where the earth lead bolts to the frame free of corrosion clean and tight? Also check the positive lead where it connects to the starter motor again free of corrosion clean and tight. Might be worth carefully splitting the switch block and giving the contacts a clean with a contact cleaning product. There are also two wires which are part of the clutch cutout switch which are prone to damage (search on here its well covered) near the headstem. This may also be worth pursuing, if you know your way around them a DC current clamp is probably helpful in diagnosing these type of faults.

[tricatcent]

I found it made a big improvement to my bikes cranking speed when I changed to 5W 40 oil from the 20w 50 that I had used previously. It started cranking pretty slow when the weather got a bit colder. At first I thought it was the battery, but after changing the oil it cranks fast now. This 5w 40 is actually what Guzzi recommends anyway. When it was 40 degrees C in Nevada in September I think the 20w 50 was OK.

[OldButNotDead]

I found it made a big improvement to my bikes cranking speed when I changed to 5W 40 oil from the 20w 50 that I had used previously. It started cranking pretty slow when the weather got a bit colder. At first I thought it was the battery, but after changing the oil it cranks fast now. This 5w 40 is actually what Guzzi recommends anyway. When it was 40 degrees C in Nevada in September I think the 20w 50 was OK.

 

This is an interesting idea. It's due for a change anyway, so I'll put that on the current idea list. Nevada's gone metric ?

 

I put a new battery in the multimeter and found:

 

12.8 V between battery terminals - ignition off

12.2 V between battery terminals - ignition (& headlight) on

10.5 V between battery terminals - engine cranking

 

0.2 V between battery hot terminal and starter - engine cranking

0.3 V between starter and battery ground terminal - engine cranking

 

10.2 V across the starter - engine cranking

 

 

I'm going to guess these numbers are pretty good, and that means the next step is a battery load test?

[docc]

Simple load test:

 

Turn the headlamp (etc) on high for three minutes and check the battery voltage.

 

Over 11.2 vDC is good.

 

On oil, I've found that Mobil 1 makes a lovely diesel truck full synthetic rated 5w-40 for 15w-40 applications (whatever the hell that means) with a CI-4 plus rating (the next best thing to old fashioned SG). And, yes, lighter cranks easier.

[Dan M]

This is an interesting idea. It's due for a change anyway, so I'll put that on the current idea list. Nevada's gone metric ?

 

I put a new battery in the multimeter and found:

 

12.8 V between battery terminals - ignition off

12.2 V between battery terminals - ignition (& headlight) on

10.5 V between battery terminals - engine cranking

 

0.2 V between battery hot terminal and starter - engine cranking

0.3 V between starter and battery ground terminal - engine cranking

 

10.2 V across the starter - engine cranking

 

 

I'm going to guess these numbers are pretty good, and that means the next step is a battery load test?

 

 

Thick oil can be an issue but it would have to be pretty cold. What is in the crankcase and what is ambient temp?

Your battery is good enough. If it was weak the voltage would drop below 10.2 when cranking for more than a few seconds. Less than .2 & .3 volt drop cranking on a circuit like that is not too bad either so connections are good. I just went out and checked my voltages for a comparison. My numbers were pretty much the same 12.6 KO; 12.1KOEO; 10.2C. The numbers don't add up to a very slow crank. If the battery were weak or the starter was drawing too many amps the voltage would drop more while cranking. Can there be something silly going on like paint between the ground stud and the starter case? Can you check ground on the starter case instead of at the cable? Just throwing stuff out here.

[Kiwi_Roy]

You could try overhauling your starter e.g. new brushes and bushes. If the bushes get too worn there is a possibility that the armature is rubbing somewhere. Starters are quite simple or just take it into an auto electrician.

I think the voltages you see are pretty reasonable.

Roy