Throwing belts.

[73GreenMachine]

Since I have started running the Cortina again, I have destroyed two fanbelts in about three days. At this stage, I am not sure what is doing it. I would like to believe its the sheer power of the motor lol but its prob something else. Maybe a small alignment issue? Its got a new Powerbond Street Balancer, thats the only difference I can think of between now and when I ran the last motor. It actually managed to rotate the belt so it wasn't running on the V anymore, but on its side!

 

[lyonsy]

hey
check if all the pullys line up by eye if they look ok then you have use for a 2l pinto cam tensioner.
all you do is bolt it up where the bottom alternator pivoit bolt is and put the tensioner about 1mm off of the belt or just touching.
this take's the wip out of the belt and stops them turning this was the only way we found on the speedway engines if dident run the tensioner 4 belts a night we whould go through.
skid

 

[Anonymous]

The run of the belt is too long on the run from the alternator to the crank pulley. This is the non drive side of the pulley system, so it is not under tension when the engine is running. When the engine is revved hard, this long pulley run combined with the harmonics of an semi counterweighted crank make the belt whip and vibrate. My solution was to remount the alternator closer to the crank like a holden six red motor. I also ran the thicker A Section fan belt available from bearing places etc. This stopped the belt vibrating as much and also stopped the belt rolling which causes it to spit off the pulleys. The standard pulleys are ok to continue to use. I also used a bigger alternator pulley off a 351 cleveland to slow the alternator down as at 6,000rpm, the alternator is doing about 13-14,000rpm. I actually broke the lower mount on the front casing of the alternator due to this. This should solve the problem.