Starter Gear Not Fully Retracting

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Jack Banville
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Starter Gear Not Fully Retracting

#1 Post by Jack Banville »

This restoration of a previously abandoned ‘63 BT6 6 volt project is nearly complete. Installed engine for the first time, did all the hookups and after building oil pressure attempted to start engine. The engine started after several attempts however upon starting it sounded like the starter gear was still partially engaged before finally retracting. I removed the engine and my suspicions were confirmed after seeing nearly half of the flywheel teeth ground on the very outside edge.

I read through forum posts on this subject and another poster had a similar problem and the solution was tied to a wiring issue. When I installed the transmission (new bushing) and new/rebuilt Bosch starter I also installed a starter relay from one of our well known vendors. I went back and re-checked all the connections for errors. I found everything in order:

#50 from ignition sw to #86 on the relay
#87 on the relay to #50 on solenoid
B+ on regulator to #30 on solenoid
#30 on the relay to #30 on solenoid
+ on battery to #30 on solenoid
#85 on relay to starter case


Has anyone experienced this? Any thoughts about what would solve this problem?

Thanks in advance,

Jack

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Doug McDonnell
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Re: Starter Gear Not Fully Retracting

#2 Post by Doug McDonnell »

Not all rebuilt starters are equal.
1965 356C 2000 BMW 740i Sport 1967 Honda CL77 There is never enough time to do it right, but always enough time to do it over.

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Mike Wilson
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Re: Starter Gear Not Fully Retracting

#3 Post by Mike Wilson »

+1

Mike
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John Brooks
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Re: Starter Gear Not Fully Retracting

#4 Post by John Brooks »

Try a drop of oil light on the bendix, and look at the and bushing for a burr. You can operate it in the bench to make sure it is retracting
John Brooks

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getting pushed around in porsches since 1965

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Ron LaDow
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Re: Starter Gear Not Fully Retracting

#5 Post by Ron LaDow »

John Brooks wrote: Tue May 21, 2019 9:13 pm Try a drop of oil light on the bendix, and look at the and bushing for a burr. You can operate it in the bench to make sure it is retracting
+1
A bendix drive is a pretty effective method to get that thing out of engagement; find out why it's not working.
Ron LaDow
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Dick Weiss
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Re: Starter Gear Not Fully Retracting

#6 Post by Dick Weiss »

Jack,

I hope you tried the stater w/o the engine installed so you can see if the Bendix will extend and retract
when stopped. Make sure the Bendix's spring isn't broken or cocked and add a little oil (or light moly grease) and hand-pull the gear to get some lube on the shaft.
Finally, don't run the starter w/o having a support on the shaft's end as the armature will drag inside the shell!

Dick

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Harlan Halsey
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Re: Starter Gear Not Fully Retracting

#7 Post by Harlan Halsey »

Bendix? The Bendix starter drive is an inertia/friction engagement drive common on American cars and English cars of the 1950s. Bosch starters use a solenoid driven engagement drive which causes the drive teeth to be fully engaged before armature drive torque is engaged. Bosch starters were one of the many ways in which VWs, BMWs and Porsches were, in my opinion, superior in those days. (You haven't lived until the know-it-all gas station guy came over to your 6v 1954 Lincoln sitting in 6" of snow and put 12v to the starter and sheared the Bendix. Had to take the Porsche to work that day.)

Someone correct me if I am wrong, it's been a while since I changed a solenoid, but I think that fulcrum on which the solenoid lever arm pivoits is adjustable with a screw on the side which allows an adjustment of the position of the starter gear/over running clutch. You might be able to adjust the retracted position enough to clear ring gear.

BTW there's no way I could bench run the starter without the end bearing. Forge had an old half transmission case we used for that.

Dick Weiss
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Re: Starter Gear Not Fully Retracting

#8 Post by Dick Weiss »

Harlan,

I didn't say the so-called 'Bendix' starter engagement unit was a friction drive; I know the engagement is
activated by a 'pulling' solenoid until the gear is engaged into the F/wheel teeth; Then the internal contact
is made to start the rotation of the gear.
If the F/wheel teeth are damaged, I've repaired a couple of 'em over the years--especially if a 6V starter was used w/a 12V electrical system w/o a solenoid change to 12V; Obviously, using a 12V starter having smaller teeth, the 6V F/wheel's teeth will get damaged in a short time, and it'll make a little noise during activation!

Dick

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George Hussey
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Re: Starter Gear Not Fully Retracting

#9 Post by George Hussey »

has to be a bad starter.
George Hussey

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Ron LaDow
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Re: Starter Gear Not Fully Retracting

#10 Post by Ron LaDow »

Harlan Halsey wrote: Wed May 22, 2019 6:35 am Bendix? The Bendix starter drive is an inertia/friction engagement drive common on American cars and English cars of the 1950s.[...]
Correct. My mistake.
Ron LaDow
www.precisionmatters.biz

Jack Banville
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Re: Starter Gear Not Fully Retracting

#11 Post by Jack Banville »

Guys,
Thank you all for your constructive input. I’ll dig into this with a whole lot more knowledge than I had when I started.
Best Regards,
Jack

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