Thread: Advice on Broken keyway for Crank

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if nothing else works, you could try this in a pinch.
wouldn't hurt to replace the old key with a new one.

Ok here's the new updated story. Fortunately I was able to take a nail punch and punch out the left-overs of the key.

So what I need to do now is clean up the scored crank. (Any reccomendations?) Take off the timing gear set, replace the keys put the timing set back on and then put the crank hub / pulley back on.

I talked to my father in law (original owner / builder) and he seems to think that key got broken from some backfiring issues he had. Those issues have since been solved. (engine was running WAAY lean)

The consensus between the two of us is, the car is not raced, no racetrack will even let is in, (bummer too) so basically my wife and I just cruise around the street in it, and since it's about 2000# the M/T's never hook up and about 200HP is all you can harness out of it anyway.

That said i think I'm just going to install new keys and call it done. If it breaks again then I'll probably have to have the crank worked on.

Do you think I could gain some extra strength by using Loc-Tite or similar on the key / crank hub?

In the mean time I've purchased a new ARP balancer bolt to replace the old Grade 5 bolt with a bent 3/16 washer. What torque should I tighten the balancer bolt and what torque should the crank pulley bolts be tightened into the crank hub? (there is 6 grade 5 bolts there)

Thanks for everybody's help!

don't forget to ping it, it will help.

well i see you will not do it right? may god help you. i would not trust it so. this would be the way to put it on the wrong way pick punch the hell out of the nose get some 620 lok-tie this would be the best stuff and will fill .020 gap and wash the nose with paint thinner it needs to be very clean before you loc-tie it and you may want to use the loc-tie primer on this put lock-tie on the crank and the inside of the hub

yeah I went through that. thanks for reminding me.
all the years you forget.
my engine couldn't have a steel crank and needed two keyways. machinist cut an extra keyway in the NEW crank and they weren't 180 apart, hub would only work one way.

I realize this isn't the best fix but the engine lasted 30 years like this so I think I can make it last a couple more with a new key. Hell it dyno'd 550 hp at the wheel with the broken key.

How should I clean up the burr's on the crank, can I just use a metal sand paper or what?

Pat I'm going to find some of that loc-tite and I'll let you know.

I would rEaLLy like to hear how this is accomplished, since ceramics are nonmetallic

ceramic key way? i think he may of meant a carbon plug that keeps the weld out of the key way or ceramic?? when it gets spray welded if this is a cast crank there would be a better steel sprayed on it making the noise as good or better like ss or nickel.

Ok for all those interested in an update. I pulled off the timing gear set and was able to remove both keys. I've started to polish up the crank a bit with some 400 grit emory cloth.

http://www.rlmdigital.com/photohost/crank2.jpg
http://www.rlmdigital.com/photohost/crank3.jpg

One more little problem. It looks like the cam gear has ground a little bit away from the bearing housing in the block. Now there's no metal shavings anywhere (before I cleaned) so I don't think it's touching it very much. Is there something I should do about this or just leave it alone?

http://www.rlmdigital.com/photohost/camgear.jpg
http://www.rlmdigital.com/photohost/cambearing.jpg

Thanks!

this is happens on big block and i would get a chain set with a roller thrust on it called torrington thrust bearing this will stop this you do not want it to keep digging in fix it now or the block will need more work . i know you do not want to take this down .but it looks like to me it getting to the point were i would fix it right so you can drive it this spring or spend all summer fixing it ?

yep that a torrington. you could buy just it and if you have a lathe cut the timming gear or just buy the set done the good set have this torrington running in a cage that works much better that the open style. if you use one drill one of the oil gally plugs out do the drive side so it get some oil on it use a .030 drill on the plug and wash the torrington good and oil it before you put it in

[QUOTE][i]Originally posted by pat mccarthy take the plug out when you drill it

the only thing that will will add is this the cage will hold it self to the gear. if no cam buttom on cover .there is a good chance the washer may get hooke up on the back side of the gear were it is cut of it so if you use this stye you should use a button on the end of the cam. the washer will ride on the top there the the block is not cut in. the rigth way to fix this is to bore the block and run a bronze washer or use a torrington and the front cam bearing helps hold it there is many ways to do this. do it the way you want i have put over 50 of this type of sets in and they work

Ok if I do that, don't I have to shim out the timing gear on the crank too? What do I use for that, just a regular shim / washer of the same thinkness?

no that will not work. if yo shim it out the oil oil pump / dist gear drive will pulll the cam in it will just dig in more. buy the chain set like i said put it on you do not need a shim .the top geat is cut for this when you buy it .DO IT ANY WAY YOU WANT YOU CAN NOT SHIM IT THIS WILL NOT WORK LIKE YOU THINK . i tried that 20 years a go had the same thing with a big block used a shim and used a gear end shim on the bottom . had it right and whent to look at it later on the shim and the the gear was dig up just as bad. big blocks is more than 90percent of what i do. this is the not the way to fix it. i know that works like i said i have bulit over 100. big blocks i not taking stock stuff. big blocks or any thing in have post in have done. if i say don t do that. there is more than one way to to some thing i have tried . it did not work . what i post would be the right way . this is all i will post and tried to help like i said this as the best way to fix it. but it not right you will have to make you mind up. i can not. i have told you over 20 years of working on big block chevys i have learned . and this is not my shops .SO do it any why you want good luck.