Starter grinding-Shim? Use 87 or Original?

[cougarmandan]

I have a question or two. I have a friend that has a 72 F-100 with a 302 and granny 4 speed. He replaced his starter and it worked fine. It had a slight grinding noise when it started, but its seamed ok for a couple of months. A couple days ago, he calls and is having trouble. The starter spins, but its not engaging. I assumed the bendix failed and we took the starter to Oreilys for a warranty replacement. They did their test and they say it tested fine. You can see where the flywheel ground some of the nose housing off plus you can see the bendix is also grinding against the flywheel. They sold him a shim and sent him one his way. The shim was too small and he messed with it and cussed at it. Finally he came by and showed me what he had. I have my 68 motor out and happened to have my starter laying nearby. We compared starters. The previous owner had replaced the starter on my rig before he sold it. He never could figure out why it wouldn't start. I took one look an the cables that had more insulation missing than it had left and suggested that. "I just push start it, its fine" he said. Anyways, after I bought it, I replaced the cables that after noon and had a fully functioning starter/Ignition switch. Anyways, back to the topic. As we are comparing, I realized my starter is doing the same thing. It hasn't been used as much so its not near as bad but I was curious what starter to use. I am going with an explorer motor and a stock 3 speed manual. The auto starters go deeper so I doubt an explorer starter is the answer. Is the shim really the answer? Its seams kind of odd that ford never used a shim. Is it a production issue with the aftermarket starters or more of a compatibility issue? Since, I am using an 87 Flywheel, will that year of starter work?

 

[68broncohalfcab]

i had a 80 bronco with a 302 and automatic it kept going thur starters. first time i changed it i did not put the shim in that came with the truck it ground bad. i put the shim back in and the noise stopped. i tried using an automatic starter and even pulled the starter out of my 68 halfcab with the 289 and 3 speed, with the shim no grinding but without it would grind. go wo\ith the shim it sometimes helps.

 

[broncnaz]

I've never had or worked on a old ford that required a shim. The bellhousings are pretty standard as the mounting flange is always the same distance away. If the flywheel is grinding on the nose of the starter then a shim probably wont help anyway. A shim will only move the starter outward toward the front of the engine not towards or away from the flywheel. A couple things to check are is there a thin block plate between the engine and bellhousing? Its helps with starter alignment. Second has the clutch been changed recently? I've heard of a few guys having issues with cheap clutches being the wrong size and hitting the bellhousing and probably the starter as well. Might want to have some one turn the engine over and watch the flywheel though the starter hole to make sure nothing is sticking out.
Without actually seeing where the flywheel is making contact with the starter its a little hard to suggest much more.

 

[cougarmandan]

How about a picture

Here's an attempt at including a picture. I need to be a little more clear. When I said nose of starter, I meant, the base of the aluminum nose piece, like the starter is going too far into the hole. I was calling the whole aluminum nose housing the nose. Anyways, you can see where there flywheel ground away at it. Its a little hard to see, but it obvious that the bendix is coming out a little too far and grinding on the teeth of the flywheel. My starter wasn't used much before I pulled the motor so its doesn't look near as bad as my friend's starter. I know a shim would help some, but I am curious if this is a production issue with the aftermarket starters or is it something you get with using a particular flywheel and starter together.

 

[broncnaz]

Ok that clears things up yes a shim would help there, Its not all that common. I've swapped a lot of ford starters and never had any issues or used any shims. But again there should be a sheetmetal plate between the engine and bellhousing usually about .080 thick. Make sure thats there. I've also seen shims bewteen the crank and flywheel a few times but they are usually pretty thin. Sometimes people for get tio reinstall these items and that cuases the problem.
I would probably just get a piece of sheet metal and make a shim for it it should fix the issue.

 

[Broncobowsher]

Looking at that starter I think the real problem is a fatigued flexplate. For the flexplate to travel that far forward that the gear is nearly at the forward mating surface there is something wrong. Another (worse) option is the thrust bearing is gone an the crank is moving that far forward.

 

[cougarmandan]

Well, they are both trucks are manual transmissions with true flywheels and both have the plate between the motor and transmission. I thought that some motors have a sheet metal shim type thing on the back of the flywheel but the more I think about it, its on the outside of the flywheel. My firends truck has a 83 302 in it and who knows what the granny 4 speed came out of. I have a theory. I am not sure how to test it yet. What I am thinking, is there might be a changes in the 50oz crankshaft/flywheel end that moves the flywheel flange closer to the block. I think my engine was an 82 but they used the C5AE flywheel (probably the original 68 flywheel). It was a ticking time bomb had it run like that very long. A thought on my buddy's truck is they may have done the same thing. His drive train is pretty pieced together and rigged up when he got it. And its has a very bad vibration at hwy speed. He bought it cause it was cheap and he's very financially limited. Another thought I had was the starter ring on the flywheel migrated forward, but its grinding the starter, not just the bendix so that's not it.

 

[cougarmandan]

OK, Theory Busted.

Using a tire depth gauge that calibrated in 32nds, I went and measured how far the crank sticks out past the block and I measured how far the rings is on the flywheel. Its the same on 351C, an 80 302, an 86 351W, and a 97 Mountaineer(Explorer) 302. Its 8/32 or quarter inch. I thought i had it on the flywheel when I got out the C5AE flywheels and compared it to the new Sachs 87 F-150 Flywheel. The older flywheels are machined a little different making it look like the flywheel flange sticks out farther. Adding a straight edge and some math, the flywheel ring gear is 3/32 deeper than the crankshaft surface on all 3 flywheels I have (351C, 68 302, and 87 302.

So back to why does this happen. I am back to thinking its either a warped flywheel or a machining variance in the starter.

 

[broncnaz]

I think its just a machining variance or wear on the crankshaft or flywheel. As Most starter nose cones are cast and not machined and usually they were on a different engine and didint have a issue. If it was a brand spanking new starter and not a rebuilt one then I'd consider it might be a starter issue.
I think if the shim was on the outside of the flywheel that may be someone just not reinstalling it in the correct location all I've ever seen were between the flywheel and crank.

 

[cougarmandan]

Epiphany!
I didn't even think about crankshaft. I bet its worn thrust bearings. When you push the clutch, its pushing the crank forward. I never looked at either of the motors, but I bet that's it. I have seen motor in the past that when you have a helper push the clutch while its running and while watching the main pulley, it would extend out a quarter inch. That would bring the clearance to zero. Holy smokes I bet that's it. When I get a chance, I going to check on the truck.

 

[Scott C.]

NAPA used to sell the shim. I don't know if they still do or not. It is very seldom ever needed. I only remember ever needing one for a 302. It was for a 74 Econiline Van with a 302 and a three on the tree. It was our shop truck.
I do recall a problem with the thrust sufaces wearing down. But those wear on automatic transmissions. Ford blamed the cause on torque converter swelling. They replaced the converter bolts with bolts that had a thinner head. I don't know if the converters were rreally swelling that much or not, but everyone that I saw also got the converter repaced.