Missing Bendix Bolt in Flywheel Housing

[sellerby]

This is my first post (well, really the second, but the first doesn't count because I unintentionally posted this message to the Swap Forum) and I want to thank the participants here for the incredibly helpful advice I've found while reading old posts and replies.

My starter motor runs but doesn't crank the engine. I removed the starter today and found that the spring bolt and special washer on the Bendix drive next to the gear end (not the drive head end) were missing. I can only assume that they now reside in the flywheel housing. Do I need to worry about removing them? If so, how best to get at them with the least amount of work?

My theory of how the bolt came loose is that the washer fatigued, failed, and allowed the bolt to gradually back out

I also noticed when examining the Bendix drive that there were no spring clips that I've seen in various Model A parts catalogs. I'll order those along with new bolts and washers. Any other suggestions on improving my Bendix drive? I saw on other posts here that the modern design starter drive has caused problems for many.

Best regards,

[1931 flamingo]

I'd start looking for those parts, do a search as this was covered not too long ago. JMO
Paul in CT

[allford]

Sellerby Get that bolt out, the flywheel can pick up the bolt and do damage to the starter ring and flywheel. Ask me how I know.

[Great Lakes Greg]

Some say to send a glob of grease around on the ring gear to pick up the bolt on the bottom. I stick a small speaker magnet on the backside of the ring gear and it has pulled up some wonderfull treaures from the bottom of the housing.

[Smokey Pickett]

I've had the problem. Fished it out with one of those magnets thats on a long flexible spring-shaft. They have them at any auto parts store.

[Big Al]

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HI,
ON THE FLYWHEEL HOUSING, HAS ANYONE CONSIDERED ENLARGING THE HOLE IN THE BOTTOM OF THE FLYWHEEL HOUSING ONLY BIG ENOUGH SO STARTED BOLTS, ETC. WOULD FAL OUT? THE HOLE,AS I REMEMBER IS JUST ABOUT BIG ENOUGH NOW.


BIG AL
i,

[Richard Redmond]

Sellerby - Hi,

I have recently been in your exact situation. There is good thread but I don't have time to link to it now.

The gob of grease did not work.

I had a telescopic rod magnet set with adjustable angle heads - that did not work.

The flexible rod with magnet head might well work.

I got a strong magnet about 1 1/2 diameter (quite chunky), tied a string to it (in case it drops !) and placed it throught the starter motor hole and clunked it onto the smooth flywheel wall beyond the ring gear. Spark plugs out - and gently rotate the engine so the magnet goes down to 6 o'clock. You can hear the lost parts clicking on to the magnet. Then gently, slowly rotate back up and gently slowly retrieve the bits and then the magnet from the hole - Hallelujah !

I too thought (in my late night desperation) of drilling out the drainage hole - but it really should not be necessary.

Why did the Bendix spring bolts fail. Note that the bolts changed from 5/16 to 3/8 after 1929 - why? Someone will tell us I'm sure. The 3/8 doesn't sound like much but in your hand they are much more sturdy. I had bought a new bendix spring but note that the larger suppliers like Mac's only do the 3/8 size. I know from my own bitter experience that trying to use 5/16 bolts with the 3/8 spring (even with new lock washers, Loctite and the add-on clips which reduce the spring 'rock' and twist) resulted in failure within about 20 or 30 starts.

RMR

[sellerby]

Well, the suggestion by Great Lakes Greg was spot on. I tried the telescopic magnet without success. Then I tried Greg's idea of attaching a magnet to the starter ring. I had some old screen door magnets (cylindrical in shape but flat on two sides) and attached one to the back of the starter ring. I turned the engine with the hand crank. Nothing. I added a second magnet to the back of the first and tried again. The second magnet was knocked off inside the housing! Yikes! So, I adjusted the first magnet, turned the hand crank, and after a few revolutions picked up the fallen magnet. Phew.

The funny part of this is that after snagging the spring bolt and special washer that had fallen off inside by using the two magnets, I snagged a second spring bolt that must have been sitting on the bottom of the flywheel housing for many decades. It had sheared off. The spring bolt that came loose recently had stripped threads. My Tudor is a 1930 yet the spring bolts were 5/16. So, looks like a prior owner did some work on the Bendix drive. However, there were no spring bolt clips that I understand were service items added in the early 30's. Thanks to you all for the great assistance.

[Maclab58]

Try a rare-earth magnet on the flywheel and crank the engine with the hand crank. They are very powerful magnets!

[Bruce Adams]

Home Depot and Sears both sell a magnet the size of a .22 caliber round which is fastened to a flexible wire looking like a roll of solder wheich is easily bent to position and fishes out your hardware in no-time.

THEN purchase the MODERN BENDIX that the vendors sell which doesn't break that way.

[Jerry Parr WI]

The top bolt in this picture was trapped between the flywheel and bell housing in my 30 Town Sedan. It suddenly started making lots of noise. Even with the engine out the bolt could not be removed until the flywheel was taken off. The balance of the hardware was stuck in the gook in the bottom of the flywheel housing and was not going to cause a problem.

[sellerby]

So Jerry, what is happening to the Bendix drive that causes such stress on the spring bolts? A bolt on mine was sheared off many moons ago and had a happy resting spot on the bottom of the flywheel housing. Then a bolt simply came loose and had stripped threads. The stripping wasn't caused by rubbing against anything after the bolt came loose, because I didn't run the engine after the starter went kaput. I see from your experience that my problem is not an isolated event. I've read posts here suggesting that the modern Bendix drive is not without its problems.

[Tom Wesenberg]

Be sure the key is in place, or ALL the turning torque goes through the bolt, which is ONLY meant to hold the drive head in place. Always use new lock wasers with the tab properly bent against the bolt head flat and the other tab tucked into the opening of the spring coil.

Not all Bendix springs used the spring clips. Many have the coil on each end with a smaller inside diameter.

[MALAK]

You definitely want to get those parts out. One day, after a Sundays drive and then lunch. Returning from the restaurant my A wouldn't start (turn over). Tried hand cranking, push starting (fwd/rev) that engine was seized solid. After slowly disassembling the engine, in chassis, it was still stuck (only the crank was left). Decided to pull engine and see what was going on. As soon as I got the engine out there it was, a Bendix bolt head w/washer, jammed in flywheel. Looks just like one of those pics by Jerry Parr WI. Keep in mind my A has been in the family for 35 years and the starter that was in the car still had both its bolts. So some 36+ years ago a Bendix bolt broke, on some previous owner, and was left to jam things up for me. There is a plus to this story: My engine is currently at H & H getting deck cracks repaired, hardened seats, big valves, new cylinders/pistons, Brummfield head, etc, etc.

[1930artdeco]

If you can, get aviation grade bolts adn then you can safety wire the heads. This should keep the bolts in place along with the lock washers.

Mike

[Tom Wesenberg]

The last engine I worked on had an extra hole in the bottom of the flywheel cover because the flywheel jammed a bolt through it while running.

[Jerry Parr WI]

Originally Posted by sellerby

So Jerry, what is happening to the Bendix drive that causes such stress on the spring bolts? A bolt on mine was sheared off many moons ago and had a happy resting spot on the bottom of the flywheel housing. Then a bolt simply came loose and had stripped threads. The stripping wasn't caused by rubbing against anything after the bolt came loose, because I didn't run the engine after the starter went kaput. I see from your experience that my problem is not an isolated event. I've read posts here suggesting that the modern Bendix drive is not without its problems.

The loose hardware was there when I bought the car so I have no real idea how the previous owner started the car. At the time I removed the hardware I checked the Bendix but did not change any hardware. I have had the car for over 25 years and never broken a Bendix bolt. The common causes I am aware of are starting with the timing advanced, jumping with 12 volts, and no lock washers. The hardware pile seems to eliminate #3. Since not only myself but also my sons have started the car many times over the years without a problem I assume some operator error to be the cause.

[sellerby]

Those are good and interesting stories of the various experiences suffered by others. I plan to buy new bolts, spring bolt clips, and new locking washers to hopefully avoid adding similar experiences to the annals of Model A lore. BTW, what do you mean, Mike, when you advise to "safety wire the heads"? I'm probably really showing my naivete.

[Elcastor]

Originally Posted by Great Lakes Greg

I stick a small speaker magnet on the backside of the ring gear and it has pulled up some wonderfull treaures from the bottom of the housing.

My Bendix Bolt sheared off and I used Greg's suggestion. I did have to move the magnet about 1/2" away from the teeth on the flywheel so the magnet could get past the cotter pin in the bottom of the flywheel housing. Once I got the magnet past the cotter pin the magnet picked up the broken bolt and lock washer first pass! Thank you Greg!!!

[ctlikon0712]

No mention of the new style drive with rubber instead of the spring? I use one in my car per the recommendation of many A owners that I met in Saint Augustine last year. I am very happy with it.