Slight damage on rod big end
#1
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Slight damage on rod big end
I'm probably being overly ****, but as I have no expert knowledge in this area, I'd like to offer it up to the pros on here to make sure this is ok.
Basically there's an area on the con rod corner where it looks like it was scraped and dug in - pushing a little bit of steel into a mound at the end:
Since I have nothing to lose besides the cost of a good used rod, I carefully took a dremel and smoothed it as flat as I could:
I understand this is probably fine, but I just want to make 100% sure before I zip up the motor and call it good. I really don't want trouble down the line because I couldn't be bothered at this stage. So much time and money invested, to me it's worth being overly cautious I suppose. and FYI, yes the crank lobes are super oil-varnished. The con rod bearings look weird because I used them for plasti-gaging (when I had different rods) but they're new.
Basically there's an area on the con rod corner where it looks like it was scraped and dug in - pushing a little bit of steel into a mound at the end:
Since I have nothing to lose besides the cost of a good used rod, I carefully took a dremel and smoothed it as flat as I could:
I understand this is probably fine, but I just want to make 100% sure before I zip up the motor and call it good. I really don't want trouble down the line because I couldn't be bothered at this stage. So much time and money invested, to me it's worth being overly cautious I suppose. and FYI, yes the crank lobes are super oil-varnished. The con rod bearings look weird because I used them for plasti-gaging (when I had different rods) but they're new.
#3
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Thread Starter
Good to hear, thanks!
I actually also have a set of 82-83 rods...I did a side by side comparison with 951 rods and they're very very similar. Wonder if I could have gotten away with them, for my sub-400whp build. Better safe than sorry I guess.
I actually also have a set of 82-83 rods...I did a side by side comparison with 951 rods and they're very very similar. Wonder if I could have gotten away with them, for my sub-400whp build. Better safe than sorry I guess.
#4
Quit Smokin'
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What does the opposite half of the rod look like? Almost looks like someone pried it apart with a small screw driver. If this was an in car repair, I would make sure there are no high spots, and let her eat. If the engine was on a stand I would at least consider getting it resized unless I was 10000% sure there are no high spots. It's hard to tell whats positive and negative from the pics. Damaged rods are no bueno.
#5
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Thread Starter
The rod cap was perfect, I have no idea what happened. 2 of these rods had 11mm tripe square nuts on them instead of the usual 14mm so somebody was in here once before. I didn't drop them or otherwise do anything that would gouge the steel like that...so I dunno.
My plan is get an oil stone or something and clean it up.
My plan is get an oil stone or something and clean it up.
#6
Quit Smokin'
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DID YOU REPLACE THE BOLTS TOO THEN!!!!????
you can't have a reasonable expectation of what the torque value is if someone changed maybe some of the bolts.
New nuts every time, I would not even consider using those bolts again, probably even on an in car repair.
I know that Porsche had rod bolt change overs for the 911, there were tech bulletins that allowed mixing the bolts in the same engine, but it did not allow two different bolts in the same rod, as the bolts had different torque procedures. Insane that they would even allow mixing within an engine. Never heard of this for 944s, but you never know.
I agree the nick is likely ok. I wouldn't consider reusing fasteners that seem to have a sketchy past.
you can't have a reasonable expectation of what the torque value is if someone changed maybe some of the bolts.
New nuts every time, I would not even consider using those bolts again, probably even on an in car repair.
I know that Porsche had rod bolt change overs for the 911, there were tech bulletins that allowed mixing the bolts in the same engine, but it did not allow two different bolts in the same rod, as the bolts had different torque procedures. Insane that they would even allow mixing within an engine. Never heard of this for 944s, but you never know.
I agree the nick is likely ok. I wouldn't consider reusing fasteners that seem to have a sketchy past.
#7
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Thread Starter
The bolts are all original, I'm aware they can be replaced but most builds have been fine with the stock bolts... correct me if I'm wrong? I'm not building an extreme power high boost engine, just a street car 2.5l.
I'm most definitely using new nuts. In fact, the entire engine has all-new hardware everywhere (except for the rod bolts I guess).
I'm most definitely using new nuts. In fact, the entire engine has all-new hardware everywhere (except for the rod bolts I guess).
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#8
Quit Smokin'
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If you're 100% sure you know what the bolts are that had random nuts, then go for it. If there's any question that they may have used something different.... into the garbage. Cleaning up after someone else's sloppy work always requires a little more attention to detail. I reused the stock bolts in my street car, with new nuts.