Bosch Starter Rebuild Kits?

[PorscheDIYer]

Hello,

I have a 1989 Porsche and it has begun to "hiccup" when it starts. I'm guessing this suggests a dead spot in the starter. This is not surprising since the starter is original. However, I am having trouble finding a rebuild kit for it. Searching on Pelican, I can only find complete starters. Searching the Internet provides the same result. But I should only need new bushings and brushes, not a complete replacement unit. May I ask if I'm missing something obvious? Are Bosch starters not rebuildable?

[T77911S]

here is a thread i did on rebuilding the starter. its not hard but you do need to solder and you need a hot iron to remove the solder on the solenoid.

you might want to say what the hick ups are since it could be something else. like bad spots on the ring gear on the flywheel. or if the starter does nothing it could be the ignition switch or wiring. it could also just be bad connections that need to cleaned, including the grounds.

personally i would try to keep the original starter. i just think they were better back then.

SOLENOID and STARTER rebuild......finally

[Quicksilver]

The most likely source if an intermittent issue is the contactor in the solenoid. The problem is the solenoids can't be disassembled. On most solenoids you can open them and the copper bolt that is the end of the contactor can be turned 180° to extend its life.

You can buy another solenoid for $$$ or do what I did: put the original starter on the shelf and put in a hi-torque starter.

[Quicksilver]

Well shut my mouth!

While I was posting someone posted how to open that stupid solenoid!!! I'll have to dig through the dust in the garage's "dead zone" and find mine so I have a ready spare.

[notmytarga]

My starter has been happier since I rebuilt it per the instructions in the great thread in the second post. My only issue was engaging the long bolts through the starter body. I thought I had stripped the threads - but the bolts were aligned in the wrong position. Firmed up well when correct. Test at most auto parts stores before reinstall! Now I don't have problems starting in the heat of summer with a hot engine.

[sugarwood]

FYI, prices for a replacement starter:
$2000 for a new Porsche starter
$500 for new Bosch starer
$125 for a reman starter.

[PorscheDIYer]

Originally Posted by T77911S

you might want to say what the hick ups are since it could be something else. like bad spots on the ring gear on the flywheel. or if the starter does nothing it could be the ignition switch or wiring. it could also just be bad connections that need to cleaned, including the grounds.

Thanks very much for the thoughtful replies. I genuinely appreciate them. T77911S, I'm reading your write up and it is great. I must say I didn't expect soldering to be required! As for "hiccups", what I mean is the car turns over and then stops briefly before resuming until it fully starts.

[Reiver]

If you want a concours 911 I understand rebuilding that lump...if not then get a high torque replacement. Lighter and more efficient and much more room in a tight space.

[Uncle Enzo]

Originally Posted by Reiver

If you want a concours 911 I understand rebuilding that lump...if not then get a high torque replacement. Lighter and more efficient and much more room in a tight space.

I second this motion. Its worth the $$ and is half the size.

[T77911S]

i did auto electric work on cars for a short while back in 90. i also rebuilt starters there when things were slow. they were the big 24v starters though.
the rebuild was just replacing the bronze bushings, a solenoid and i think brushes.

the hard part with these is the soldering. you have to clean all the gunk off and you need a pretty good iron. when you put the iron to it, add some solder to it, it helps transfer the heat and melt the old solder. then clean it real good again. you may need flux depending on how clean it is. once the solenoind is off, a trick to get the old solder off is to heat it up, then quickly bang the solenoid on the bench. be careful doing it.
the other thing is to clean the part that the brushes ride on with 600 grit paper.
just my opinion, i would rather rebuild my original starter than to get a new one, even a high torque starter.
there is really not much to them. just make sure the gear moves in and out easily, clean it, lube it and put it back in.
the other big thing with starters is the electrical system. all your large power cables need to be clean. both positive and the grounds. people over look the grounds for some reason.

the yeallow start wire is a problem. it is a long way fomr the ignition switch to the starter. the solenoid requires a LOT of current to pull in. connectors and corrosion at connections reduce this current. (one of the reasons i say DO NOT put car alarm systems in that put a relay in the start circuit). make sure the power into the ignition sw has a clean connection along with the yellow wire. it also needs to be clean at the 14 pin connector in the engine bay. also make sure the connection to the starter is good. i like to solder that connector on at the starter jsut for a better connection.

i tried to do the solenoid on my BMW but the ends were crimped on.

if you can get the solenoid and yours is bad, i would just replace that.

[PorscheDIYer]

This is all very enouraging. Thanks. I am a bit unnerved by the idea of soldering. But the worst I can do is break a broken starter, right? May I ask where one can get the parts: solenoids, brushes, bearings? I don't see Bosch starter rebuild kits for sale anywhere. So I assume I will have to assemble my own.

[911pcars]

If there's a starting issue that can be traced to a broken solder joint at a convenient connection, yes, it might be possible to repair as a DIY project. However, all it takes is an open circuit or a leak in the insulation in an armature or field coli winding to render the DIY repair moot (unless you have the facilities to rewind either one).

Sherwood

[sugarwood]

Originally Posted by Uncle Enzo

I second this motion. Its worth the $$ and is half the size.

Got a link to these high torque replacements?

[Uncle Enzo]

Originally Posted by sugarwood

Got a link to these high torque replacements?

Pelican Parts - Product Information: PEL-GE-STHT

[T77911S]

Originally Posted by 911pcars

If there's a starting issue that can be traced to a broken solder joint at a convenient connection, yes, it might be possible to repair as a DIY project. However, all it takes is an open circuit or a leak in the insulation in an armature or field coli winding to render the DIY repair moot (unless you have the facilities to rewind either one).

Sherwood

all you have lost is some time if it does not work vs spending money on something you may not need, plus look at the experience you get.

the rebuilds main purpose is to extend the life of the starter, mainly the solenoid. that contact in there gets SO burned that it will cause intermittent starting or mainly just the "click". the rest just makes sure everythinig is moving freely along with a good clean contact for the brushes.

i did notice my engine was turning over faster after i did this.

[psalt]

Hello,

I have a 1989 Porsche and it has begun to "hiccup" when it starts. I'm guessing this suggests a dead spot in the starter. This is not surprising since the starter is original. However, I am having trouble finding a rebuild kit for it. Searching on Pelican, I can only find complete starters. Searching the Internet provides the same result. But I should only need new bushings and brushes, not a complete replacement unit. May I ask if I'm missing something obvious? Are Bosch starters not rebuildable?


Take a look in the archives, this is a common problem. My experience is that Bosch rebuilds are not very long lasting because the parts they replace do not address the issue that causes the intermittent starting. Most of the cores are +25 years old and after replacing many rebuilds after their short life, I have moved on to the gear reduction starters which are much more reliable. That is after you have eliminated all of the switch and wiring issues that come with a 911. My advice is to by pass all the wiring with jumper cables, a known good battery and a remote switch before condemning the starter.

[911pcars]

There was a time when one could source a solenoid replacement. It's been awhile and I don't know if that is easily source today.

Other than replacing the brushes, truing the armature commutator and/or repairing any visually obvious open circuit connections, there isn't much one can do to "DIY rebuild" a starter motor. However, performing the above can often restore a borderline-acting motor. Rewinding armature and field windings is a job for a business that rebuilds motors.

A so-called "hi-torque" motor is actually a low amperage, low-torque, "high-speed" motor rotating a gear reduction assy. to drive the starter pinion gear - sort of like a transmission in 1st gear (~3:1) instead of in a direct drive gear like 4th (~1:1 ).

Sherwood

[T77911S]

when i was younger and was playing around with VW's, i you could jsut replace the solenoid.

[Reiver]

Originally Posted by T77911S

when i was younger and was playing around with VW's, i you could jsut replace the solenoid.

When I bought my 911 it had the original starter in place with a second solenoid screwed to the firewall and slaved in place....worked great but I wanted to clean the area up and bought a high torque lighter unit.
I think the solenoid was from a garden tractor or something...was still working well when I pulled it.
What a heavy lump tho.

[turbo951]

Hello guys ,I realize this is an old post . Just so you know I can get you what you want to rebuild your original starter... Any questions just pm please . Thanks Russ