starter judders 416-8 onan

[longbikez 3]

Hi Folks it's been a long time but I've been fighting this for years.

1. My tractor seems to be charging ok, voltmeter above battery voltage unless I throw on the lights when it hovers just barely above. (but I am running taillights plus an electric fuel pump which it never had originally) The lights are nice and bright at 3k rpm as expected

2. The tractor will crank and start fine if it only sits for a week but beyond that when I crank it sounds like the solenoid is just not positively engaged (no grinding or zing or clicking) I call it a judder for lack of a better term.

All this led me to think tired battery

3. I have repeatedly run through the charging tests and have found nothing I could definitely put my finger on, I do not have any access to an ammeter.

4. the battery is 2 yrs old and I took it to the store and they said it was AOK which kind of surprised me thinking they missed out on selling me a new one, but I'm not arguing, I have cranked it hard with the coil disconnected and the caps off and never saw a boiling cell.

5. I have had two different V-regs through the years of diagnosing this and replaced the chassis mount solenoid and the kind of melted original old 30-amp fuse and holder by the starter.

Here's where I am now:

With the negative battery lead disconnected and a voltmeter in series with everything off I read 12v, I was expecting zero, pulling the 30amp fuse to the Vreg turns it to zero

Neither of my AC wires to the stator shows any continuity to ground

I also tested the Vreg sitting in my spare parts and it shows a continuity from one of the AC terminals to the B+ (possibly some solid-state thing I don't understand)

 

Is This Normal? the 12v reading I got on the inline voltmeter and the somehow connection between B+ and one AC in the Vreg?

I guess I am looking for a parasitic drain but in my lack of experience may be looking at something that is entirely normal

Right now I am keeping it on a maintainer, which circumvents the problem.

Thanks in advance for any ideas!

[gwest_ca-(File Mod) 11,041]

2 hours ago, longbikez said:

 

With the negative battery lead disconnected and a voltmeter in series with everything off I read 12v, I was expecting zero, pulling the 30amp fuse to the Vreg turns it to zero

It is a good test but very vague. You are measuring voltage in an attempt to measure current. Even 1/10000000000 of an amp of current flow will give you a 12 volt reading.

 

2 hours ago, longbikez said:

Neither of my AC wires to the stator shows any continuity to ground

I also tested the Vreg sitting in my spare parts and it shows a continuity from one of the AC terminals to the B+ (possibly some solid-state thing I don't understand)

You are correct. One of the AC leads is connected to the DC+ inside the regulator. This does not cause a parasitic draw.

 

The draw could be in the 30amp circuit. Put the fuse back in and disconnect the next item on that circuit one at a time to isolate the cause.

 

What is your tractor model and serial number so we can look at a diagram.

 

Is the battery clean and dry? If not that can cause a parasitic draw.

 

[longbikez 3]

Hi thanks for the reply!

Model 31-160801

Other number on plate: 36667

Year: 1989

I looked at the wiring diagram and that's all there is on this circuit B+ at starter pole-30amp fuse-VReg per pg. 7-69 Demystification guide wiring diagram

It's a heavy 10/12 awg red wire

 

trpdemys (1).pdf

[gwest_ca-(File Mod) 11,041]

I see what you are saying.

If you pull the wires off the regulator with the 30 amp fuse installed does it go to zero volts?

 

It may be a very slight draw that is normal. Try a test light instead of the voltmeter and see if it lights or tries to light - very dim.

If you get this far most multimeters will handle very low current. See how many milliamps it draws. Most meters are fused for 3 or 5 amps. 

[longbikez 3]

Unfortunately, I no longer have a multimeter, I will try a peanut bulb, I already tried touching the wire to the battery in total darkness looking for a little spark and there was nothing.

I do want to dig a little more into the charging and thought $12 for an inductive amp indicator (NAPA 700-1712 Inductive Ammeter gets good reviews).

I know it's not accurate, but it should give me an idea on cranking and charging.

I'm sort of leaning to the idea that the starter may be drawing too much due to age, combined with me running 20w50 motorcycle oil added to all the other old age stuff. Sort of like my health at 72.

Like I said, hooking the jumpers to the car it spins right up, or keeping it on the maintainer (which I do in the winter for plowing) it spins right up.

Maybe I'll age out before it really pukes or maybe it will before that and I'll have something definitive to replace.

I'd have bought a new tractor long ago if I could find one with a decent plow that ran a 38" deck (impossible to find)

I'm certainly not going $200 on a new starter at this point just for a try-to-see.

The last time I was here it was the governor plate slipping causing runaway rpms, RS got me fixed up with a homemade delrin block fabrication that is holding for years (knock on wood)

I've been exclusive WH since 75 when I bought a brand new 310-8 which I didn't take proper care of. I swear that 310 was better at plowing than the 416. I was young and too busy to do anything but pour gas in it and use cheap oil, alas.

[Boeckling Club 0]

I have a 91 416H with 2 cyl Onan engine that will not start with the key switch, but can be hot wired to start so the solenoid and starter work. I believe all the safeties are satisfied as the idiot lamps seem to work. Studying the wiring diagram, I see there should be a Starter Relay, but don't know what it looks like or where it would be located and how to test to see if it is good.my dealer is 5 weeks out pon service, but nobody told my grass. Any suggestions would be appreciated. Thanks 

[lynnmor 7,305]

There are three relays behind the battery, they are best accessed by removing the belt guard.  The relays are the same and can be swapped for testing. They can be purchased at most auto parts stores.

Edited June 30, 2022 by lynnmor

[longbikez 3]

Back to the starter judder op.

The inductive amp indicator (not a sophisticated gauge) says I'm cranking at just over 200amps on a 70degree morning cold engine and I'm charging at 15amps WOT dropping to 5amps with the lights on (front and rear lights plus electric fuel pump)

1. I think that's a bit much amps on the start but I have nothing to compare it to. Has anyone ever looked at cranking amps on the p216 onan?

2. I'm not real thrilled with the charging but I only put the lights on when I'm plowing in the road so for now, I'm not digging there

New Starter Time? just about 1k hours on this tractor, whether the starter is original is unknown as I bought it used at 900hrs.

Any help appreciated gwest-ca or others

Thanks!

[lynnmor 7,305]

You said it spins right up when jump started, this tells me the starter is working and the problem may be the battery or wiring.  I would skip the amp meter and use a voltmeter.  Have the battery charged for ten hours and then take it to an auto parts store to have it tested.  If it tests good, then try starting with the battery cables cleaned at both ends. If it starts OK, then report back with the voltage at the battery while running at least half throttle.  And no, I never checked the amps on my Onans for any reason.

[longbikez 3]

You might have misunderstood, I wasn't jumping the starter, I'm hooking the clips to the battery (a typical jump start)

1. battery is kept on a maintainer and is charged up 12.5v

2. All wiring has been checked and cleaned, all is ok, also checked starter bolt and engine mounts

3. parts store has given the battery flying colors 3 times

4. voltage at speed is 13.8-14.0(no lights on, just electric fuel pump running, it's a tick tick type from Aircraft Spruce) After a mow session I put the maintainer back on and it goes to solid green within seconds

FWIW

Today I learned the rule of thumb is 1amp per cu in, I probably knew that a hundred years ago but forgot

The onan is roughly 50 cu in, draw should definitely be under 100a (still waiting for someone to chime in) mine is just under 200a

I took the meter to my Tacoma 4L v6 (245 cu in) and it cranked at roughly 225amps

this kind of tells me this meter is in the ballpark for accuracy

Any Thoughts? Anyone?

Things that halfway work are so much fun!

I appreciate everything we've covered so far!

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[longbikez 3]

While I've been waiting on a Stens starter that appears to be lost in the Amazon ozone (BTW the first "Stens" they sent was NOT a Stens, it was Chinese something),

 my voltage regulator caught fire!

What a mess cleaning that up and repairing the wires.

I put an old one on out of my spares box and that all seems good.

I've read a couple reports on these p216 v-regs going up in smoke, it was purportedly a real Stens but who really knows as they don't seem proud enough to actually put their name on it, I called Stens and you can guess about how much they really cared.

[Jeff-C175 7,202]

9 minutes ago, longbikez said:

NOT a Stens, it was Chinese something),

 

I don't think Stens actually manufacturers their own stuff. They buy crap and put it in their boxes.  Or just ship it in a blank box.

 

 

[lynnmor 7,305]

There are genuine Onan starters made in Japan by Mitsubishi and there is all the rest made cheaply in China.

 

Did you have the battery connected backwards?

[longbikez 3]

To jeff: if they eventually ship a no-name with no documentation believe me it's going right back.

To Lynnmore: No the battery was not reversed and I sure would appreciate it if you could point me to the correct real starter because I can't make heads nor tails out of the onan parts page, P216 starter yields nothing.

[lynnmor 7,305]

2 hours ago, longbikez said:

To jeff: if they eventually ship a no-name with no documentation believe me it's going right back.

To Lynnmore: No the battery was not reversed and I sure would appreciate it if you could point me to the correct real starter because I can't make heads nor tails out of the onan parts page, P216 starter yields nothing.

Onanparts.com shows an original starter for $299.00

[Handy Don 12,217]

4 hours ago, longbikez said:

To jeff: if they eventually ship a no-name with no documentation believe me it's going right back.

To Lynnmore: No the battery was not reversed and I sure would appreciate it if you could point me to the correct real starter because I can't make heads nor tails out of the onan parts page, P216 starter yields nothing.

When I was last at the A-to-Z shop, they had several Onans in their boneyard. A call to them might get you a "tested and known to work" used one.

[longbikez 3]

Thanks!

[longbikez 3]

Today I showed the regulator to a friend who knows electronics, he said it's not a real voltage regulator but a 1/2 wave rectifier and to clean out the housing and he'd show me how to put a quality unit in it.

Meanwhile, the used one is working great, it's a Stens but it's over 10 yrs old so maybe they bought better quality then. 

He told me that the junky one was most likely leaking AC into the DC output (said an O scope would have proved it) and that this would really mess with the battery. He also said that when it started over volting that was its last gasp before going up in smoke.

So, for two mows now there has been no irregularity and no starter judder on crank, therefore I am going to continue monitoring B4 buying a starter despite the ammeter readings.

I'd like to thank everyone who offered their help and wish you all Happy Horsin' Around.

[peter lena 8,625]

@longbikez  that pile of wires and anything related to it , should be cleaned up , those onan units are known for wiring issues , relay shorting , chafing wires etc. lots of shorting / burning . would also go thru that starter  to verify what's working , do a graphite lubrication rebuild , would also , do a graphite check on those flywheel teeth . those back feeding wire burn outs , are showing you the way .  just sayin , pete