Shovelhead A place to talk about Shovelheads.

Runaway Starter!

Thread Tools
 
Search this Thread
 
Old Sep 19, 2008 | 02:23 PM
  #1  
vetto's Avatar
vetto
Thread Starter
|
Cruiser
Joined: Jun 2008
Posts: 202
Likes: 1
From: S.E. Connecticut
Angry Runaway Starter!

I posted a problem in the electrical section...but that forum doesnt get much traffic. Can one of you awesome riders take a peek at https://www.hdforums.com/forum/ignition-tuner-ecm-fuel-injection/278402-runaway-starter.html
and let me know what you think?

(basically my starter started and wouldnt stop - rolling the motor until the battery died!)
 
Reply
Old Sep 19, 2008 | 02:55 PM
  #2  
Rodney's Avatar
Rodney
Road Master
Joined: May 2007
Posts: 953
Likes: 8
From: Central Oregon
Default

A relay short could cause this and I have had miss alignment of the clutch drum / ring gear to the starter drive case the starter drive to not release as it should.
Charge your battery back up with the cables removed.
check all of the primary and secondary cables and wire in the starter circuit for shorts or heat damage due to the excessive starter draw.
once charged touch the cable to the battery and see if the starter still wants to engage.
if not the started drive may have been stuck in the ring gear.
time to pull the outer primary and take a look.
 

Last edited by Rodney; Sep 19, 2008 at 03:02 PM.
Reply
Old Sep 19, 2008 | 03:07 PM
  #3  
FilthyLucre's Avatar
FilthyLucre
Road Master
15 Year Member
Joined: Jun 2008
Posts: 1,078
Likes: 39
From: NW Florida
Default

That can be caused by the solenoid sticking as you guessed. Sometimes rapping on the solenoid with a screwdriver handle is enough to get it to release. It can also be caused by a stuck or shorted starter button. It happened to mine a few times. Once it was the button the other times it was the solenoid. My guess is that if you disassemble the solenoid you will find the contact plate pitted and burnt. They can be rebuilt by reversing the plate and cleaning up the bottom of the large contacts. The aftermarket solenoids are not very good and I went through a lot and a bunch of rebuild kits before I found a NOS Harley Solenoid.
 
Reply
Old Sep 19, 2008 | 03:30 PM
  #4  
crampfan's Avatar
crampfan
Cruiser
Joined: May 2007
Posts: 207
Likes: 1
Default

Also if your battery voltage is low the contacts in the solenoid will weld closed. (low voltage = high amp draw)
 
Reply
Old Sep 19, 2008 | 03:59 PM
  #5  
vetto's Avatar
vetto
Thread Starter
|
Cruiser
Joined: Jun 2008
Posts: 202
Likes: 1
From: S.E. Connecticut
Default

actually I = V / R
so as voltage drops so does current for the same resistance
 
Reply
Old Sep 19, 2008 | 04:52 PM
  #6  
vetto's Avatar
vetto
Thread Starter
|
Cruiser
Joined: Jun 2008
Posts: 202
Likes: 1
From: S.E. Connecticut
Default

OK. Just got back from work and put the battery on the charger....
The neg battery wire connections to the frame are electrically fine, and from the ground wire to the starter body is 0 ohms.

The pos lead is a 0 ohm ground to the frame. Crap.

Checked the starter switch, intermittent contact when the switch is closed, but the short doesn't seem to be there. Gotta find the relay (gotta love home-made bikes that you didn't build)

I got a schematic and am pretty good at reading them, so off we go!

Anyone got a schematic of the starter connections? I know what the two main lugs are, but there are more wires and connections back there. I will look for a diagram also, just thought I would ask.
 
Reply
Old Sep 19, 2008 | 06:01 PM
  #7  
sqdealgeorge's Avatar
sqdealgeorge
Road Warrior
Joined: Dec 2007
Posts: 1,854
Likes: 20
From: Eagle River WI
Default

A weak battery can cause this condition What happens you hit the start button the solenoid throws out the starter gear to the clutch ring gear the battery tries to turn the motor over ( not enough ***** ) the gear gets hung up because the engine didn't start to throw out the starter gear and then we have what is called an emergency situation !
 
Reply
Old Sep 19, 2008 | 06:05 PM
  #8  
vetto's Avatar
vetto
Thread Starter
|
Cruiser
Joined: Jun 2008
Posts: 202
Likes: 1
From: S.E. Connecticut
Default

The bike did not start... I dont understand why a stuck gear in the ring would cause the starter to not stop after the start button was released with the bike not running.
 
Reply
HD Forum Stories

The Best of Harley-Davidson for Lifelong Riders

story-0

7 Surprising Harley-Davidson Products that Are Not Motorcycles

 Verdad Gallardo
story-1

8 Best Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-2

10 Worst Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-3

Killer Custom's Jail Break Is The Breakout That Refused to Blend In

 Verdad Gallardo
story-4

Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

 Verdad Gallardo
story-5

Harley-Davidson Reveals Super Cool Cafe Racer Concept

 Verdad Gallardo
story-6

Engraved Rebellion: Inside Bundnerbike's Glam Rock II

 Verdad Gallardo
story-7

10 Motorcycles You Should Never Buy

 Joe Kucinski
story-8

10 Things Harley-Davidson Needs to Fix in 2026

 Verdad Gallardo
story-9

Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider

 Verdad Gallardo
Old Sep 19, 2008 | 07:21 PM
  #9  
vetto's Avatar
vetto
Thread Starter
|
Cruiser
Joined: Jun 2008
Posts: 202
Likes: 1
From: S.E. Connecticut
Default

Just a question, before this happened the starter rolled the motor over really slowly and after three compression strokes the bike would start. Battery voltage was always fine and the motor is relatively stock (mid eighties STD engine).

I am really starting to think that I have a weak ground somewhere. How do I check voltage drop at the starter once this short is fixed?
 
Reply
Old Sep 19, 2008 | 07:21 PM
  #10  
megawatt's Avatar
megawatt
Road Warrior
Joined: Dec 2007
Posts: 1,286
Likes: 64
From: SoCal
Default

I have personally had the situation sqdealgeorge described. More than once! It was a defective battery. The starter gear engages, the starter motor starts to run (slowly), the starter gears are held engaged due to the torque that is applied. The solenoid pull-in coil voltage is reversed when you release the starter button (which I have assumed counters the hold-in coil) and the solenoid spring is not strong enough to move the linkage back to the disengaged position. I can also imagine that the starter contacts could get welded together under those conditions.
Here's another "fun" situation. With the spark plugs removed, I tried spinning the engine with the starter...when I released the starter button, the engine continued to spin then as well. With the plugs installed, it would not do that. I pulled the plugs again and tried it once more with the same result.
The only way I could stop the whole mess from dragging the battery down as well as melting the battery case and cables was to disconnect the battery ground at the frame as quickly as possible.
 
Reply



All times are GMT -5. The time now is 06:08 AM.

story-0
7 Surprising Harley-Davidson Products that Are Not Motorcycles

Slideshow: The bar-and-shield logo shows up on far more than motorcycles, some of the company's most unexpected products have nothing to do with riding.

By Verdad Gallardo | 2026-04-29 16:50:35


VIEW MORE
story-1
8 Best Harley-Davidson Motorcycles Ever

Slideshow: Not every Harley gets it right, but these are the ones that genuinely earned their reputation.

By Pouria Savadkouei | 2026-04-15 14:23:21


VIEW MORE
story-2
10 Worst Harley-Davidson Motorcycles Ever

Slideshow: From the troubled AMF years to modern misfires, these bikes earned reputations for reliability issues, questionable engineering, or disappointing performance.

By Pouria Savadkouei | 2026-04-01 20:01:09


VIEW MORE
story-3
Killer Custom's Jail Break Is The Breakout That Refused to Blend In

Slideshow: Killer Custom's "Jail Breaker" build focuses more on stance and visual aggression than mechanical overhaul.

By Verdad Gallardo | 2026-03-18 19:20:32


VIEW MORE
story-4
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

Slideshow: The Swiss custom shop has taken a Harley Softail and stretched it into something so long and low that it looks closer to a rolling sculpture than a conventional motorcycle.

By Verdad Gallardo | 2026-03-07 16:15:30


VIEW MORE
story-5
Harley-Davidson Reveals Super Cool Cafe Racer Concept

Slideshow: Harley-Davidson's new RMCR concept revives the café racer formula with modern hardware-and it may be exactly the reset the company needs.

By Verdad Gallardo | 2026-03-04 12:23:37


VIEW MORE
story-6
Engraved Rebellion: Inside Bundnerbike's Glam Rock II

Slideshow: A standard cruiser becomes an intricate metal canvas in the hands of a Swiss custom house known for pushing Harley-Davidson platforms far beyond their factory brief.

By Verdad Gallardo | 2026-02-24 18:19:44


VIEW MORE
story-7
10 Motorcycles You Should Never Buy

Slideshow: There is no shortage of great motorcycles to buy, but we would avoid these ten.

By Joe Kucinski | 2026-02-19 14:50:51


VIEW MORE
story-8
10 Things Harley-Davidson Needs to Fix in 2026

Slideshow: Harley-Davidson's challenges aren't abstract; they show up in dropping shipments, shrinking dealer traffic, and strategic decisions that aren't yet translating into growth.

By Verdad Gallardo | 2026-01-13 18:33:17


VIEW MORE
story-9
Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider

Slideshow: Graeme Billington's left-hand-drive Shovelhead is as much about problem-solving as it is about classic Harley form.

By Verdad Gallardo | 2025-12-30 11:27:08


VIEW MORE