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Discussion Starter #1
Just pulled the pistons out of my motor because of my cam wiping lobes off. What would cause the top edge of the rings to be razor sharp? Poor oiling? Also one of the rods does not move nice and freely on the wrist pin like the other 7 do. What would cause this? They are pressed pins. Its not super tight but the rod doesnt flop around as easliy as the others do. Will this hurt anything? Let the beer drinking commence now. My $700 Eagle Forged crank is shot. I dont think turning it .030 will take care of things either. Anyone need a boat anchor?
 

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Well 3 lobes on the cam are totally gone and those lifters have some deep slots worn in them. First time I've ever seen that. The Rod bearings look brand new but the mains have deep lines into the copper babbit which doesnt make sense. The oil passages are connected to each other. The cam bearing also look perfect. It just gets better the deeper I dig into this POS. Gonna take the crank to NAPA tomorrow and see what can be done. If it can't be saved it looks like I'll be crusing the town in the golf cart this summer. Fiance won't let me spend any more $$ on the car. It's my money damn it. :mad:
 

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Piston rings are supposed to have sharp edges on them. As for the rod being tight, it may have gotten too hot and been starting to gaull up.
 

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Just pulled the pistons out of my motor because of my cam wiping lobes off. What would cause the top edge of the rings to be razor sharp? Poor oiling? Also one of the rods does not move nice and freely on the wrist pin like the other 7 do. What would cause this? They are pressed pins. Its not super tight but the rod doesnt flop around as easliy as the others do. Will this hurt anything? Let the beer drinking commence now. My $700 Eagle Forged crank is shot. I dont think turning it .030 will take care of things either. Anyone need a boat anchor?
you might be able to let someone weld up the crank and turn it back down.....a friend of mine done this to his 304 jeep and his looks brand new......better than scrapping it!!! i believe there are shops that do this now......ask the machine guy at napa.they might can point you in the right direction
 

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Are you running a solid hub or first gen fluid damper? I learned the hard way not to EVER run one of those POS's. It did exactly what you are describing to my 432 BB,cam wiped, main bearings went south, along with turning the timing chain into an op art masterpiece. This was all done by runaway harmonics. An imbalance can also cause the described results. Another thing that can cause that, is oil restrictors in the block. They are not necessary.

And just FYI. I used nodular cranks in my 355's and ran the crap out of them @ 7500 RPM. The only failure was an SPS rod bolt. Another mistake I will never make. Ohio crank has some nice cranks for not a lot of cash.

And have that rod honed!
 

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Ah, ok then the piston must be galled, starting to sound like an oil problem. Either a restriction or a pump problem. Wait, now a 400 is externally balanced. Do you know if they had to add a lot a weight to get it balanced? If thats actually the case then you may have a real problem. I have never heard of a legit shop doing this. Double check.
 

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Discussion Starter #9
Ah, ok then the piston must be galled, starting to sound like an oil problem. Either a restriction or a pump problem. Wait, now a 400 is externally balanced. Do you know if they had to add a lot a weight to get it balanced? If thats actually the case then you may have a real problem. I have never heard of a legit shop doing this. Double check.
Don't know for sure its off a 400. Just going by what I've seen in Summit and Jegs. All the 8" balancers in there are for 400's. 7's and 6's are usually for the smaller guys.
 

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Well 3 lobes on the cam are totally gone and those lifters have some deep slots worn in them. First time I've ever seen that. The Rod bearings look brand new but the mains have deep lines into the copper babbit which doesnt make sense. The oil passages are connected to each other. The cam bearing also look perfect. It just gets better the deeper I dig into this POS. Gonna take the crank to NAPA tomorrow and see what can be done. If it can't be saved it looks like I'll be crusing the town in the golf cart this summer. Fiance won't let me spend any more $$ on the car. It's my money damn it. :mad:
OH LORD! Don't take that awesome crank to Napa! Use a well respected machine shop in town that specializes in performance engines. Napa is fine for run of the mill projects. You'll be suprised at what those guys can repair:eek:
 

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I learned the hard way not to EVER run one of those POS's
I've had the same Fluidamper for about 15 years, used it on several engines without any issues.
8" balancers on stock 350's are pretty common stuff; several million of them.
 

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OH LORD! Don't take that awesome crank to Napa! Use a well respected machine shop in town that specializes in performance engines. Napa is fine for run of the mill projects. You'll be suprised at what those guys can repair:eek:
Absolutely!!!
 

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Discussion Starter #14
Don't worry guys. I took the Crank to Hunts Machine Shop this morning not NAPA. One of friends fathers is good friends with them and he said they should be able to save the crank by just going .020 under. As soon as I brought it in he says "what brings you here?" I'm like well my cam wiped out 3 lobes and beat up my bearings pretty good. He instantly says "not using the Zinc oil huh?" I'm like WTF did everyone know this but me? Hes also going to loosen up that one stuck rod on the wrist pin for free. So in total he says its $175 to turn the crank and polish the journals. I guess I can live with that.

Can I use a brake cylinder hone to the lifter bores to make sure there arent any burrs in there preventing the lifters from spinning?
 

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I've had the same Fluidamper for about 15 years, used it on several engines without any issues.
8" balancers on stock 350's are pretty common stuff; several million of them.
The one I meant was the solid hub.Never, ever, run one of those. The very early first fluidampers had problems with the viscous fluid being too darn viscous and it would create an out of balance situation until it warmed up.

Lifters not spinning in the bores would be a symptom, not a cause.

You would be better off with a small, fine grit ball hone than the usual 3 stone type. But VERY gently! If you go overboard on this, you are looking at getting your lifter bores bushed.
 

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Ditto. Should be cheap.:yes: More machine shops I've used had a solid piece of bar stock that was turned down to be used as a "Go-No Go" gauge.:yes: It literally took a couple seconds to check them.:yes:
 
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