Sealed Power Chain hitting crank WTF!!

[KWIKR 1]

I've been trying to track down a engine noise on a new rebuild . After the engine builder tore down the engine he noticed marks on the front of crank where the crank gear sits . It looks like the Sealed Power double roller chain (#220-3111) is actualy coming in contact with the front of the crank. It is leaving little even nicks all around on the front of crank due to the roller pins coming in contact with it . We tried the crank gear on a different GN turbo crank. we put a little blue paste on the shoulder of the crank. and the chain seems to be hitting it as well . How much clearence should there be between the back of the chain and crank ? It almost looks like the crank gear could of been machined wrong . Is that possible???? any comments?

** gear is on right **

 

[Intercooler]

I know dumb question but it is on correct?

 

[KWIKR 1]

yep it's on right . the 3 key way timing degree marks/numbers that are imprinted on the front can be seen when looking at it head on .

 

[Jimn8or]

Take it off, put on a Cloyes, all steel, factory replacement set and a new tensioner from the General...forget about all your timing chain worries forever.
HTH
Jim

 

[Roger]

Jimn8or is 100percent correct!

 

[KWIKR 1]

Jimn8or, this is a chain set by Federal Mogal that has been used on many a GN engine .

 

[GNVAIR]

I think you will find the vast majority of Buick people including myself prefer the stocker. They are very durable and last a long time and have no bad side effects. Plus you have the tensioner which removes the slack. The roller chains will stretch right away and once they do, you are stuck with the slack. I'd spend the $25 and get a new stock replacement chain and gears and a new tensioner from GM.
Just my $.02

 

[KWIKR 1]

I guess one problem being is that the DR cam gear and cam have already been machined to get proper end play clearences with roller kit . also I have been lead to believe that a double roller chain was needed or should be used when using a roller cam with higher spring rates .

 

[KWIKR 1]

Well guys , new Sealed Power roller chain set came in . We refitted the new crank gear to my crank and another turbo crank in the shop . Same thing no clearence between chain and front of crank . We then fitted it to a NA Buick 3.8 crank and the clearence was fine between chain and crank face . Go figure . There was also a difference of .020-.030"(from collar to shoulder) between where the gear sat on the NA crank and where it sat on the turbo crank . So my builder suggest that he may send the crank out and get about .030--.045" machined from the front of the turbo crank to increase the clearence between gear (chain) and crank face . Has anybody ran one of these SP roller sets and notice any wear marks on crank face ???