Theres 153 and 168 tooth flywheels. Are there anymore?
No. Chevy uses a number of different noses for their starters. The size of the flywheel and year and model of engine determine what nose is needed. The 153 tooth flywheel is smaller in diamaiater than the 168 tooth flywheel. If you want to use a starter from a 168 tooth flywheel on a 153 tooth flywheel the nose from the smaller flywheel starter will have to be exchanged onto the larger flywheel prior to using it.
Yes it will. Both blocks take the same bellhousings. Now, the 250 might not have the hole tapped for the correct starter for a 168 tooth flywheel, but you can either drill and tap it if necessary, or just use a 153 tooth flywheel and bellhousing.
yes. a starter made for the 168 tooth flywheel would not engage a 153 tooth flywheel.
The gear is the same, but the nose cone is different.
Flywheels are fitted by engine and crankshaft pattern. Not bell housing diameter
Just as the name implies the 168 tooth flywheel has 168 tooth ring gear and the 153 tooth flywheel has 153 teeth on it's ring gear. In the "old days" of high performance the manual 4 speed transmissions allowed a larger diameter 11" clutch to be used with the higher performance engines with the larger 168 tooth wheel. In addition to this the larger diamater flywheel gives the starter better mechanical advantage to turn over high compression engines because of the greater number of teeth on the larger ring gears. Chevy uses a number of different starter noses on their starters. This is the aluminum piece that the bendix gear is in at the "business end" of the starter. This nose is the piece that mounts the starter to the block. This nose is the part of the starter that moves the starter motor in closer to the flywheel on the 153 tooth and farther out away from the flywheel on the 168 tooth wheels. I believe the starter motors are mostly the same except for the HD starters which have a longer stator and rotor for the high compression engines of "the old days". These longer starters allowed the starter motors to develop more torque to turn the higher compression engines over to start them.
Some starters are intended for a 153 tooth flywheel, some for a 168 tooth flywheel. Most 307's had 153's, and most 350's had 168's, but you could put a 153 on a 350 or a 168 one a 307. Both engines are internally balanced, so as long as you have the correct starter for the flywheel, it will work. The one other difference between Chevy starters, is the length of the armature. The longer one is heavy duty, the shorter one is standard duty. Either will work as long as it's mated with the right flywheel.
Depends on what the 305 is in, a 305 camaro engine needs like a 9 tooth starter because the fly wheel is 12.75 inches in diameter with 50 some teeth. A 305 in a Chevy half ton will have like a ten tooth starter for the 14.25 inch diameter flywheel that has like 60 some teeth. All 305 engines before 1986 are the same they did have different flywheels for what ever Chevy put them in. 1986 and newer 305's had different cranks the flywheel bolts up different on a 1986 305 compared to a 1983 305.
Could be either a defective starter drive or a broken tooth on flywheel Try turn the engine manually (large socket on crankshaft) to see if it will start- if so problem is a broken tooth - if not problem is probably a bad starter drive. (make sure vehicle is in neutral if std.)
Most of those engines were drilled for either starter bolt pattern. What matters is that you get the right starter for the size flywheel you're using. The 153 tooth and the 168 tooth require their own starter nose cone. Except for the aftermarket gear reduction starters which are usually drilled for either flywheel.
164 tooth 28 oz
Counting the teeth sounds like a good way.