Chewed up flywheel

You will need a new one. Also check the starter gear and make sure it's not buggered up also. Bad alignment is usually the culprit.

Can't help you with the flywheel except to say that since it has to come off you can look on it for a stamped part number then have NAPA look up the part.

Doug, how do you make sure the starter is aligned properly?

Somebody might correct me here, but the Iron Duke was the 4-banger engine, and nothing else.

Can you connect the starter to the battery and see if the noise is still there? My guess is that the marks on the flywheel and the noise yo report are not related. If so, the marks are probably not important -- they've been there a long time, no point in worrying abut them now.

In any case, if you elect to go after the flywheel, it would be a good time to consider a clutch because you'll have it off anyway.

The alignment of the starter would not change over night. If the starter has been working fine for years, and suddenly started to make noises, then the alignment is not the likely problem.

The starter has a gear that has a one-way clutch inside. The clutch can fail, and this can be noisey. The starter also has bearings that can fail.

Doug and Bill both bring up excellent points, but they would make problems pretty much immediately when the issues came up. The alignment would not change if the bolts were right, and if the bolts were wrong, the noise would start immediately.

If you recently replaced the starter, and wondered why all of the racket was going on, then Doug and Bill would have good stuff to be looking at. Since the problem seems to be that everything worked fine for a long time, now it works not-so-fine, then the stuff that would have changed is wear to the one-way clutch or the bearings. Both of these require the starter be removed, whereby you can inspect the bolts and the mating surfaces of the starter and the block to be sure the starter was fitted properly.

Jeff, Bill, and Doug,

We took the starter off today and the ring gear is chewed up in a spot about

The starter is making the noise as it's not engaging the ring gear. Rather, it's just grinding the shit out of the ring gear. There was quite a bit of metal filings attached to the starter gear when we took it off.

NAPA will just farm the job out to a local machine shop in most cases. Look around for a shop that specialized in automotive machine work - they can press that gear off/on easily - I've had them do while I waited. If it's a good shop, they can also get you the right gear (or tell you where to get it) and probably give you a good idea of just what caused the damage in the first place.

Thanks Will

If it's like a tractor flywheel then the teeth are a seperate ring that's held on purely by friction. You basically cut the old ring off then heat the new one up to about 200. After it's hot you just drop it down on the flywheel and it shrinks to fit. I do not recommend doing this yourself if you haven't done it before.

The reason I mentioned NAPA is they have a good parts crossreference. I agree with Will that you should find a good local machine/engine shop.

Chewed up in one spot is not unusual. Engines tend to stop at the same point in rotation every time. There are four angles where the compresion is least on an 8 cylinder, but for some reason it will favor only one and that's where the ring gear will wear out. If this engine is internally balanced, (No big segments machined or cast out of the flywheel) one "fix" is to rotate the flywheel on the crank. The correct repair is to replace the ring gear or flywheel.

Are you sure?!

I've never ever heard that theory -- the engine will stop in the same place. It sounds like an absurdly implausible theory to me.

The engine will stop as soon as there is no spark to make it go, and it's not gonna wait until it gets to the next compression stroke. There is a compression stroke every 90 degrees of engine rotation, when the spark is removed -- engine idle is assumed -- the motor will stop because of the existing compression on which ever piston is at the top of its stroke plus the building compression of the next cylinder in the order. Since the flywheel goes around twice to fire all eight cylinders, the odds of it stopping on the same 4-inch section with any regularity is very remote, and is entirely based on the odds by the way.

PS I ignore any condition or malfunction such as spontaneous combustion that causes some motors to run on and on while you are walking into the supermarket with smoke beltching out of the carburator and/or tailpipe. My comments are confined to properly operating engines. Turn the key off and the engine stops turning -- for any practical purpose -- instantly.

Ok, we'll drop the tranny this weekend. Is it easier to remove the tranny, transfer case, and bell housing as one unit i.e. only remove the bell housing bolts and drop the whole thing. Or, do I need to unbolt the tranny from the bell housing, and then take off the bell housing?

Thanks

Jeff, mine always stops at the same place: 180 degrees from where I want it to stop so that I have to manually rotate it the maximum amount. I think that's due to Murphy rather than mechanics, though. You're analysis is right on.

My tiring 6 with 200k on the clock will hold the thing on one hill where I frequently park about one time in 10 - probably because the cylinder with the best compression is on the compression stroke when the engine stops. Any other combo will let it slowly creep past tdc, then gain enough momentum before the next cylinder gets to tdc to just keep creeping right on down the hill.

For things like this, I'm a fan of Harbor Freight. They had a floor jack with a tranny cradle that replaces the lift plate cheap enough it wasn't worth the hassle. The cradle gives you a lot more stability and comes with chains to keep it in place while you maneuver it out. You'll find the hardest part will be disconnecting the transfer case linkages and getting it off before backing the tranny out (you can remove them as a unit but unless you have some really tall jack stands or a lift it's pretty awkward to manage, not mention heavy). The last challenge will be finding and reaching the two male Torx bolts at the top of the bellhousing ;-).

It is very odd Jeff, but it does happen that way. The teeth will always be torn up in certain places with the ones between like new.

As mentioned, usually 180 off too....

Mike

It can't be possible for anything other than the luck-of-the-draw that the engine tends to stop in the same place. Just because an entirely random event repeats itself does not mean it's not random. The location that the engine stops at is nothing but the very definition of "random event."