Working on a 351 windsor engine for my '73' Maverick. The engine was built by a race shop back in the mid 80's & was in the basement since '98' when I started to take over this project. I'm having a major problem with the crankshaft. I put the timing chain on & start to set the valves. When I was half way though the chain stopped turning. The bottom sprocket on the crank for the chain let loose. It looks like the sprocket was almost slipping all the way past the keyway! It was biting by only a few thousanths. I have an old 302 crank that I used to see if their was any difference. On the 302 with the sprocket all the way on the crank it bites about half way through the sprocket, like it should. When the chain was on the Windsor it looked to be in perfect line. (from cam to crank). I've talked to some Ford race guys on this one & their stumped! Could the race shop have put a 400m crank in a Widsor block? The chain is for a small block ford engine. The only thing on the build sheet for the engine is that the crank was turned & nitrated. I'm confused. Anyone that could help with this would be much appreciated! Thanks.-
It sounds like you're saying the keyway in the crank snout is too deep for the key you are using. If you don't have a dial caliper for precision measuring, you should get one. Every car nut should have one. Period. With a dial caliper you can acurately measure the width and depth of the keyway in the snout and the crank sprocket. Add the two depth dimensions together then take those dimensions to the auto parts store, along with the length of the keyway, and I'll bet they can hook you up with a key that will work. Keys are pretty cheap. If you want, you could cut out a paper template that matches the radius at the bottom of the crank keyway to make sure you get one with a good fit. I hope this helps.
Thanks for the reply. You were correct, the key was not the right one for the Windsor crank! Thanks a bunch. I installed the correct key & installed the timing chain about an hour ago & ran into even a bigger problem. The sprocket, when all the way installed, goes right pasted the key. I'm looking @ it from every angle & it all looks true. Shouldn't the gear be at least half-way though the key? With the chain in place, the key is completly exposed. This is a Ford Motorsport dual roller timing chain which I had verified today. It is for a small block Ford. I went to Ramchargers today & found out that their is two chains for the small blocks. 1- for standard fuel pumps. 2- if u are using an electric pump. The difference was very little. If I were to use the other chain, it would engage the key, but by only a 1/4". This doesn't seem like very much! Past engine's I've built, the key would engage 3/4 of the gear. I don't want to start this engine with the current problem. I hate to give up on this, I know somewhere lies a solution to this! Thanks for your help. :confused:
Check the distance from the end of the crank to the beginning of the keyway. Compare that against your old 302 crank. If there's a significant difference you may have to remove the crank and have a machine shop lengthen the keyway for you. That's about the only thing I can think of at the moment
The distance for the 302 is 1/2" & on 351 crank it's 11/16". This isn't good. I'm looking @ the 351 crank & there is a small scribed line toward the back of the keyway. I measured the distance to the scribed line & it's exactly a 1/2". It looks like the race shop forgot to finish up the work to the crank. This isn't good. Thanks again for your help! It looks like I'm in a pickle!
