Notices
928 Forum 1978-1995
Sponsored by:
Sponsored by: 928 Specialists

928 Coke Car: Starter not engaging. What to do?

Old 05-18-2017, 11:57 AM
  #1  
AO
Supercharged
Rennlist Member
Thread Starter
 
AO's Avatar
 
Join Date: May 2002
Location: Back in Michigan - Full time!
Posts: 18,925
Likes: 0
Received 59 Likes on 33 Posts
Default 928 Coke Car: Starter not engaging. What to do?

Hey guys,

At my last track day the Coke car started having issues with the starter. It got progressively worse throughout the day to the point that now, I cannot start the car. The starter motor spins fine, but it's as if the solenoid doesn't engage with the flywheel. Sometimes it engages for a little bit, but not long enough to start the car. It's an original-style starter (not a lightweight) as seen in the pic below.

Doing a search showed that the common failure mode is that the starter stays engaged, which is the opposite of my issue. Another failure mode is the motor itself won't turn - which is not the issue here either.

I'll be diving in later tonight, and was wondering if anyone has had this issue and how it was resolved? Can I service the solenoid? I have an old starter where the motor wore out. Can I Frankenstein the two?

Thanks for your help!

Old 05-18-2017, 12:12 PM
  #2  
hacker-pschorr
Administrator - "Tyson"
Lifetime Rennlist
Member
 
hacker-pschorr's Avatar
 
Join Date: Aug 2001
Location: Up Nort
Posts: 1,445
Received 2,065 Likes on 1,177 Posts
Default

When I said a few of us would be at Road America for track support, I don't think we planned on push starting you 4 times a day
Old 05-18-2017, 12:16 PM
  #3  
AO
Supercharged
Rennlist Member
Thread Starter
 
AO's Avatar
 
Join Date: May 2002
Location: Back in Michigan - Full time!
Posts: 18,925
Likes: 0
Received 59 Likes on 33 Posts
Default

Originally Posted by Hacker-Pschorr
When I said a few of us would be at Road America for track support, I don't think we planned on push starting you 4 times a day
That's why I 'm trying to sort it out now. You guys will be drunk off your asses or hungover. Either way, you'll be just as reliable as the current starter.
Old 05-18-2017, 12:18 PM
  #4  
Rob Edwards
Archive Gatekeeper
Rennlist Member
 
Rob Edwards's Avatar
 
Join Date: Sep 2002
Location: Irvine, CA
Posts: 17,295
Received 2,541 Likes on 1,228 Posts
Default

Total WAG, grease cooked out of it by the heat from the headers and there's too much resistance for the bendix to do its thing? Perhaps a heat blanket would be good prevention in the future (?)
Old 05-18-2017, 12:22 PM
  #5  
AO
Supercharged
Rennlist Member
Thread Starter
 
AO's Avatar
 
Join Date: May 2002
Location: Back in Michigan - Full time!
Posts: 18,925
Likes: 0
Received 59 Likes on 33 Posts
Default

Sounds reasonable. I was wondering if it was heat related too. Never clean/opened a started. But you did, right? How hard is it to get in there to clean/re-grease?

Is there a way to "bench-test" these things, safely?
Old 05-18-2017, 12:28 PM
  #6  
Rob Edwards
Archive Gatekeeper
Rennlist Member
 
Rob Edwards's Avatar
 
Join Date: Sep 2002
Location: Irvine, CA
Posts: 17,295
Received 2,541 Likes on 1,228 Posts
Default

I got as far as cleaning the armature and R&R'ing the brushes but didn't mess with the bendix.

Seth has gone deep into the starter, details starting in post #9 of this thread:

https://rennlist.com/forums/928-foru...er-refurb.html
Old 05-18-2017, 12:41 PM
  #7  
skpyle
Rennlist Member
 
skpyle's Avatar
 
Join Date: Jul 2014
Location: Blacksburg, SC
Posts: 2,886
Received 469 Likes on 212 Posts
Default

AO, you can mix and match starter pieces no problem. Swapping solenoids should not be a big deal. See my thread that Rob referenced.
However, opening the solenoid is a different animal. You have to unsolder the solenoid coil leads. I chose not to do that.

Good Luck! With both your starter and hungover pit crew...
Old 05-18-2017, 12:42 PM
  #8  
AO
Supercharged
Rennlist Member
Thread Starter
 
AO's Avatar
 
Join Date: May 2002
Location: Back in Michigan - Full time!
Posts: 18,925
Likes: 0
Received 59 Likes on 33 Posts
Default

I'm on it! Thanks guys! WIll post the outcome later tonight/tomorrow.
Old 05-18-2017, 12:58 PM
  #9  
KenRudd
Drifting
 
KenRudd's Avatar
 
Join Date: Jun 2008
Location: Apex, NC
Posts: 2,080
Received 2 Likes on 2 Posts
Default

Have you tried striking it with a hammer...
Old 05-18-2017, 01:07 PM
  #10  
AO
Supercharged
Rennlist Member
Thread Starter
 
AO's Avatar
 
Join Date: May 2002
Location: Back in Michigan - Full time!
Posts: 18,925
Likes: 0
Received 59 Likes on 33 Posts
Default

LOL! Not yet. But when I get it on the lift...
Old 05-18-2017, 02:53 PM
  #11  
M. Requin
Rennlist Member
 
M. Requin's Avatar
 
Join Date: Mar 2007
Location: Central Virginia
Posts: 3,624
Received 59 Likes on 38 Posts
Default

Striking!? Tapping! Tapping! It does work- on everything from MGB's to John Deere equipment in my experience. (YMMV of course)
Old 05-18-2017, 02:56 PM
  #12  
KenRudd
Drifting
 
KenRudd's Avatar
 
Join Date: Jun 2008
Location: Apex, NC
Posts: 2,080
Received 2 Likes on 2 Posts
Default

You have to ask: At what point did it become such an issue that Bosch/Porsche had to create a special sticker to address the problem???
Old 05-18-2017, 02:57 PM
  #13  
SeanR
Rennlist Member
 
SeanR's Avatar
 
Join Date: Apr 2006
Posts: 35,700
Received 498 Likes on 266 Posts
Default

Disconnect your 14 pin connector and touch pin 14 to the jump post and see if that gives it enough voltage to engage. Might want to ensure it's in neutral tho.
Old 05-18-2017, 03:01 PM
  #14  
KenRudd
Drifting
 
KenRudd's Avatar
 
Join Date: Jun 2008
Location: Apex, NC
Posts: 2,080
Received 2 Likes on 2 Posts
Default

Google provides answer. Apparently very common and very "verboten"






Old 05-18-2017, 03:06 PM
  #15  
KenRudd
Drifting
 
KenRudd's Avatar
 
Join Date: Jun 2008
Location: Apex, NC
Posts: 2,080
Received 2 Likes on 2 Posts
Default

Down the rabbit hole: If there is no sticker, is it okay, or even REQUIRED, to strike with hammer?

"Everything which is not forbidden is allowed"

"The jocular saying is that, in England, "everything which is not forbidden is allowed", while, in Germany, the opposite applies, so "everything which is not allowed is forbidden". This may be extended to France—"everything is allowed even if it is forbidden"—and Russia where "everything is forbidden, even that which is expressly allowed". While in North Korea it is said that "everything that is not forbidden is compulsory"

Thread Tools
Search this Thread
Quick Reply: 928 Coke Car: Starter not engaging. What to do?



All times are GMT -3. The time now is 07:31 PM.