Mercury crankshaft
- Thread starter elwood
- Start date
texas webb
Well-known member
looks intentional.
It is in the area where excess weight often needs removed for balancing. I would suggest that is the most likely explanation.
Whether or not I would use it would depend on the level of performance the engine was being built for. But, if it is ok in all other respects I doubt it would be a problem in the average street performer.
Whether or not I would use it would depend on the level of performance the engine was being built for. But, if it is ok in all other respects I doubt it would be a problem in the average street performer.
flatheadmurre
Well-known member
Ive seen some pretty rough machining on them...if it´s to remove casting inlets or balance...but looks like they used a blunt axe sometimes...just check for sharp deep cuts that can be the start of cracking...otherwise i wouldn´t worry to much.
I was going to say the same. Seems like an awful lot to take off to get it to balance. I guess the shop's drill bits were lost when they balanced this crank. LOL!
rotorwrench
Well-known member
These crankshafts were cast in a gang. The sprue ports interconnected in the mold so that cast iron would reach all the areas of the mold. When they broke the cranks apart, it sometimes leaves some jagged areas so areas like that were generally machines smooth just like removing flashing. It was rudimentary machining so it wasn't always purty.
flatford39
Senior Member
You need to get that thing balanced at a machine shop. I sincerely doubt it can be. That's probably why it's not in an engine. I wouldn't use it.
It passed inspection at the factory and doubtless ran for many years and miles without any problems. A lot of unwarranted assumption going on here.
34 GAZ
Member
Re: Mercury crankshaft inspection before grinding
So what does a balanced crank look like ? Would you actually see tell tale grinding marks on the counterweights or are they polished and smooth with all casting blems removed ?
So what does a balanced crank look like ? Would you actually see tell tale grinding marks on the counterweights or are they polished and smooth with all casting blems removed ?
rotorwrench
Well-known member
They generally just drill into the counterweights to remove weight or add weight depending on the imbalance characteristics. We had a discussion on here before about cranks that had more metal loss than expected when the gang of shafts were separated at the foundry after casting. There have also been some discussions about balancing.
Prepping one for racing applications is a lot more involved than just balancing one.
Ford would grind off lumps and smooth out flashing before machining the shafts for front & rear shafting & flange, oil flow ports, and bearing journals. I don't know what there inspection procedures were but they likely performed some NDT inspection to weed out any that were obviously not going to pass QC. The clean out plugs would likely have been the last thing installed. Balancing would have been performed prior to sending them on to the assembly line. Sometimes the funky looking stuff lasts longer than the nice looking stuff.
Prepping one for racing applications is a lot more involved than just balancing one.
Ford would grind off lumps and smooth out flashing before machining the shafts for front & rear shafting & flange, oil flow ports, and bearing journals. I don't know what there inspection procedures were but they likely performed some NDT inspection to weed out any that were obviously not going to pass QC. The clean out plugs would likely have been the last thing installed. Balancing would have been performed prior to sending them on to the assembly line. Sometimes the funky looking stuff lasts longer than the nice looking stuff.
