Sean79 5spd

I have destroyed two Bosch starters. When I activate the starter there is lots of noise when the engine turns and starts. However, in the process, dust cap and seal on the pinion are torn out and end up in the bell housing. I have also tried one of the hi performance starters from Carl. This starter engages the "flywheel" sometimes but mostly just spins. It seems l almost like the pinion is not properly engaging or releasing from the teeth. Can't see how anything could be misaligned. I did re & re the clutch and replaced the ball cup on the release arm but I did this to try to solve the starter problem.

Any ideas?

Mrmerlin

Without any pictures it’s hard to guess what’s happening
That said could the engine have been jacked up using the bell housing maybe it’s bent
your engine uses the bell to hold the starter
when did the starter not work ?
Could it have been after you replaced the clutch
possible the starter got hit and bent the housing?
I suspect your answer will be near what was the last thing I fixed

Wisconsin Joe

It sounds like the starter isn't aligned right (Captain Obvious, at your service).
First off, what year? I think some years use the bell housing, others use a bracket that bolts to the back of the block (could be wrong on that).

When did it start doing this?
Did you bottom the car out?
Are both starter bolts fully tight? (the upper one isn't any fun at all)
Is the bell housing bent or cracked?
Does the starter look like it's straight?

Answer both these & the ones above from MrMerlin.
Post a pic of underneath.

Sean79 5spd

It is a 79 and the starter bolts to the lower bell housing section. There is no alignment options that I can see. I don;t ever recollect seeing any shims under the the starter flange. I am going to check the bolts between the engine and upper bell housing this morning. It is possible but highly unlikely that they have come loose.

Thanks for the input.

Seab

dr bob

Sean --

A reminder that you can do a lot of starter-drive testing by actuating the solenoid with the battery disconnected. In this case you'll want to lift and isolate the positive battery cable from the post. Then connect a separate starter button (diagnositic tool you can buy) to the battery positive post and the 50 terminal on the solenoid. The 50 terminal is one of the two smaller connections on the starter solenoid, the one labelled 50 with what once was yellow-insulated wire attached. Once connected, the starter button will activate the solenoid, causing the Bendix to push towards the flywheel. It should engage the teeth of the flywheel, but with no battery connected to the starter motor nothing will spin.

Example remote starter button:
You can see all this going on with the lower bellhousing cover removed.


While you are there, look for scraping or bent sections that might give you a clue about something that's been moved or bent. The fact that you've tried several starters with the same result points then towards the ring gear, the clutch section where the ring gear mounts, or misalignment due to impact or other damage.

In actual service, the engine will likely find one of three "normal" places to stop when the key is shut off. Use a paint marker to indicate where the flywheel is when you first look, so if you are back in there again you can see if the line-up is different. Look for burrs or other damage on ring-gear teeth, something that's keeping the drive gear from full engagement. Note that the solenoid should push that drive gear in, but it also depends some on initial turning of the starter for that initial line-up. The ring gear teeth have almost no "lead-in" relief on them, while the starter drive gear teeth have a lot.

Jason89s4

Ditto....what was the last thing you worked on in that area?

Sean79 5spd

Thanks everyone. I haven't done any work on the car in years other than add the hi torque starter about 3 years ago. I think I am going to replace the ring gear and see if that makes a difference, it definitely looks worn. I will post a pic when I have the started out.. Thanks DR Bob about the tip on activating the bendix only, might save me some in starter repairs.

Sean

Mrmerlin

if you can remove the lower bell housing as well and take some pictures of the flywheel. and the starter
what precipitated this starter malfunction?

C531XHO

doesn't the starter bolt onto a bracket which is itself bolted into the block? Or is this different on the early cars. Loose bracket could surely cause misalignment?

Sean79 5spd

Some pics below. The 79 had no bracket, bolts directly to the lower bell housing section.

Thanks
Sean

Ring gear teeth

More ring gear teeth

View of clutch components

Hi Torque starter. Will turn the engine sometimes but just spins most of the time.

Bosch starter with damaged pinion seal and dust cap

Bosch pinion teeth

Mrmerlin

Please answer this question.
When did the starter stop working properly?

what happens when you fit the original starter?
these new starters might not hold the same dimensions.

That new starter is made to fit the bolt on engine bracket,

IDK if the mounting dimensions are different.
\ Your ring gear teeth are damaged and this may require you to procure another ring gear I plate.

Sean79 5spd

All started a couple of years after I installed the hi torque starter. It started to spin without engaging. I then changed back to the Bosch starter. Then it started to jam and I would have to tap it with a hammer. Finally took it off and had it rebuilt in a shop but the problem didn’t go away.

Sean79 5spd

Is the hi torque starter not designed for a 79?

GregBBRD

Everything you need to know is in this picture.

Look at the teeth on the Bendix. On the OD of the teeth on the gears, the first 5-6mm is shiny and has rust on each tooth. The teeth should never touch, where these teeth have wear. The only way this can occur is for the teeth to be bottoming out in the base of the teeth on the ring gear, correct? This will jam the Bendix into the ring gear. Once the Bendix is jammed, it is not going to retract freely and the Bendix/starter are going to be spun by the engine, once the engine runs.

This destroys starters, very quickly.

What is the only part that determines the distance from the starter Bendix to the ring gear?

Yup, you need a new/used/different lower bell housing cover. (Apply some logic.....Porsche didn't change that lower cover that originally held the starter to a big steel bracket that attaches to the block because they needed to make more parts to inventory or they needed to spend more money.....they had to have had "issues", to make this change.)

And BTW....that ring gear is toast, from this, also.

reanimotion

also check the alignment of the engine and upper bellhousing, the two lower surfaces should be level at the join on both sides of the engine
there are a couple of locating dowels aligning the two and I've encountered one vehicle here where one of them was missing
The missing dowel allowed the bellhousing to shift and pulled the starter out of alignment, causing pretty much exactly the problem you have