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Discussion Starter #1
I'm a noob with just enough experience in fixing vehicles to be dangerous. So be gentle! Lol...

My starter is toast. I shut my truck (1984 Bronco with 300) off yesterday and I heard a very loud buzzing coming from under the hood. I popped the hood and the starter was smoking. So I bumped the key and it stopped.

I took the starter off and it is in rough shape (picking up new one tomorow). But the flywheel teeth are nicked up.

Should I replace the flywheel immediately? Or do I have time that I can drive it as I wait for money and the means of pulling the engine to get to it?

More importantly... What causes this? I dont want to replace the flywheel and buy a new starter just to have to do it again.

I can post pictures of the flywheel teeth if anyone would find it helpful.
 

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yo,
Possible reasons;
Drives, Exploded, "Shims for Ford 2 bolt type, WAI PN 76-2306; "Shims needed due to worn thrust bearings in engine; Replaces Ford D7TZ-11N004; 2.3mm (.090 in.) T; Used w/ 2 or 3-hole D.E. housings. On engines with worn thrust bearings, the excessive crankshaft end play may cause pinion damage when the flywheel moves toward the starter. The 76-2306 helps prevent pinion damage by backing the starter away from the crankshaft flywheel..."
Source: by wai-wetherill.com


Drives, Exploded, Ford 2 bolt type, Shims needed due to worn thrust bearings in engine; "...This condition is the result of the drive engaging too deeply into the flywheel. The face of the drive is rubbing on the flywheel and gradually cutting into the cover that holds the drive together. Eventually, it cuts through and the drive comes apart. The damage is not caused by a problem with the starter. It is because the flywheel is floating as a result of worn thrust bearings, located inside the engine block, whose function is to keep the crankshaft centered. This wear can be enough to cause starter and ring gear engagement problems on an engine with 60,000 or more miles. It might take a long time to destroy the original starter, but when a new unit is installed, the drive can be quickly destroyed. Therefore, it is important to properly diagnose this problem when inspecting the customers original core rather than providing him a replacement unit. Shims are availalbe from OCA, part number F.S.S.2B
Source: by mrreman.com via web.archive.org


Pinion to Ring Gear Clearance Info; "...If the thrust bearing for the crankshaft is worn enough, there will be excessive endplay, which means the crankshaft and everything bolted to it will move forward and rearward a small amount. This can affect the meshing of the gear teeth because the flywheel may be moving enough to let the edges of the teeth get worn down until the teeth are ground off on the edges and no longer catch. The starter would spin but not engage. Look carefully at the wear pattern on the old starter teeth and compare it with a new unit. The wear pattern should be on the meaty center part of the gear, minimizing the wear to the edges. To check the crankshaft endplay with precision requires a dial indicator rigged to measure the fore and aft free movement of the crankshaft. Take the belt/s off the crankshaft pulley and see if it seems to move too much in and out when you push in and pull out on the crankshaft pulley. To repair a worn thrust bearing requires some serious effort. I am not sure if you are willing to do all that, some people install HELP! brand starter shims to space the starter further away from the flywheel, but this is more for concerns where the starter fails to disengaged. There is a difference between the manual transmission and automatic starters, so make sure you get the right one. Some auto parts stores may have incorrect listings Also check the thin metal sheet that the starter inserts through for distortion of the hole, which can cause misalignment. There is a shoulder on the starter that needs to engage the edge of the hole in the sheet metal evenly. This helps ensure the starter sits squarely so it lines up. Drives, Exploded, Ford 2 bolt type, Shims needed due to worn thrust bearings in engine; This condition is the result of the drive engaging too deeply into the flywheel. The face of the drive is rubbing on the flywheel and gradually cutting into the cover that holds the drive together. Eventually, it cuts through and the drive comes apart. The damage is not caused by a problem with the starter. It is because the is floating as a result of worn thrust bearings, located inside the engine block, whose function is to keep the crankshaft centered. This wear can be enough to cause starter and ring gear engagement problems on an engine with 60,000 or more miles. It might take a long time to destroy the original starter, but when a new unit is installed, the drive can be quickly destroyed. Therefore, it is important to properly diagnose this problem when inspecting the customers original core rather than providing him a replacement unit. Shims are availalbe from OCA, part number F.S.S.2B; Shims; Tilton Engineering 54-958 Brand: Tilton Engineering Product Line: Tilton Starter Shims Part Type: Starter Shim Kits Part Number: TIL-54-958 Shim Material: Steel Starter Bolts Included: Yes Quantity: Sold as a kit. "...These Tilton starter shims are a must when installing a starter. You'll need these shims to ensure proper gap between the starter and flywheel..." thus Tilton shows this Pinion to Ring Gear Cearance Info & DiagramI hope this helps to show what can happen. I own a 1988 F-150, and it has 245,000 miles. I replaced the original starter about 4 years ago and have had good results since. I have not checked endplay, but have heard of people with up to an inch of endplay where there should be a just a small amount of play. When obtaining a replacement starter, get one from a smaller local rebuilder that specializes in alternators and starters (check yellow pages or web). These smaller shops handle rebuilds with more care and in general, they tend to use better quality parts than the mass rebuilders that supply the chain stores. They are also good to talk to in a case like this since they have seen so many failed starters..." Miesk5 Note, see reply for the Tilton URL or see Link listed in this section
Source: by Brian at justanswer.com

Pinion to Ring Gear Clearance Info; "...When installing the Permanent Magnet Starter, the relationship between the pinion and ring gear is important. Due to the starter's high operating torque, damage to the pinion and ring gear will occur if the recommended clearance is out of spec. The clearance will typically be in spec if you are using the correct starter for your application. There is a much greater chance of having clearance problems if you have a modified flywheel, ring gear, bellhousing or crankshaft. Tilton Engineering Product Line: Tilton Starter Shims Part Type: Starter Shim Kits Part Number: TIL-54-958 Shim Material: Steel Starter Bolts Included: Yes Quantity: Sold as a kit. "...These Tilton starter shims are a must when installing a starter. You'll need these shims to ensure proper gap between the starter and flywheel..." thus Tilton shows this Pinion to Ring Gear Cearance Info & DiagramI hope this helps to show what can happen. I own a 1988 F-150, and it has 245,000 miles. I replaced the original starter about 4 years ago and have had good results since. I have not checked endplay, but have heard of people with up to an inch of endplay where there should be a just a small amount of play. When obtaining a replacement starter, get one from a smaller local rebuilder that specializes in alternators and starters (check yellow pages or web). These smaller shops handle rebuilds with more care and in general, they tend to use better quality parts than the mass rebuilders that supply the chain stores. They are also good to talk to in a case like this since they have seen so many failed starters..."
Source: by Tilton Engineering

Pinion to Ring Gear Clearance Info; "...When installing the Permanent Magnet Starter, the relationship between the pinion and ring gear is important. Due to the starter's high operating torque, damage to the pinion and ring gear will occur if the recommended clearance is out of spec. The clearance will typically be in spec if you are using the correct starter for your application. There is a much greater chance of having clearance problems if you have a modified flywheel, ring gear, bellhousing or crankshaft. 1) The starter pinion to ring gear clearance should be.090" ± .030" when pinion is in its relaxed position(Figure 1). 2) When the pinion is engaged into the ring gear, there is to be .010"-.030" backlash between the teeth of the gears. Make sure the battery is disconnected before making this check. To measure, one tooth of the pinion gear should lie along a line between the centers of the pinion and ring gears, as shown in Figure 2. Wire type feeler gauges, or number drills may be used while removing the entire backlash in one direction with a screwdriver. 3) If the starter solenoid interferes with the engine block or any engine component, see if the nose on the starter is an indexable model. If so, the entire starter can be rotated about the nose to gain additional clearance. Tilton Engineering Product Line: Tilton Starter Shims Part Type: Starter Shim Kits Part Number: TIL-54-958 Shim Material: Steel Starter Bolts Included: Yes Quantity: Sold as a kit...."
Source: by Tilton Engineering
 
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