I have done hours of reading and researching about these notorious rod benders, but what I want to know and have not found out is...
Can you pull the oil pan and actually see if any of the rods are bent, is it easily noticable, or when they bend is it ever so slight that you cant see it without actually measuring it. I wouldnt mind popping off the pan and checking at the next oil change. Whats it take, couple of hours and a gasket? If you have a bend rod and its noticable and you are not using any oil yet, then wouldnt it be wise to remove the head and pop out the pistons and upgrade the rods before there is any damage. So what if you spend $1500 in rods and parts and do it yourself. Its alot better than a major rebuild or R&R or resleave the cyls etc....

So does anyone know if bent rods are visually noticable or if you have to remove them and measure to find out if they are bent?
Is there any pics of some that have been removed that are bent?

So far my 91 350SDL runs perfect and has used no oil in the last 1800 miles that I have owned it. I have been carefully watching it.

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Generally, they bend very slightly. Just enough to drop the compression and begin to ovalize the cylinder over several thousand miles.

If it was a catastrophic bend, the vibration would be severe and the engine would run very poorly.

You'll never see it if you drop the pan and look. Don't waste your time.

the way i can see if the rods are bent is to remove the head,take each piston to tdc,look at the level of the piston to see if it is out of level with the parting surface of the block.once the rods are removed it is obvious as you lay them on each other and turn them over to compare.
still say the pan needs to come off to address the loose bolts that are suppose to retain the oil baffel plates, bet you a dollar to a donut hole you find them loose or some of them at the oil pump.
try this, remove the low oil float assy on the oil pan, use a magnet on one of those flexible shafts, fish a while and tell us what u find,the oil pump pick up is in center of the pan right in front of the hole for the low oil float u removed. use a mirror and you can get your direction to fish. if u do catch some bolts be sure and count washers.
i dont think u needs a fishing permit,
larry perkins lou ky 85 old cars

consider draining the oil from the oil pan as i dont know if the oil level will be below the float assy hole or not.
larry

bill... 350SDL i cant wait to see this beast..

Wouldn't there be some sort of fancy (maybe laser based?) tool that you could use up in there to determine if the rod is perfectly straight or not? I have no idea, I was just wondering about it....

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Oh, I'm sure you could probably dream up something. But, you would need a proper frame of reference. You would have to mount the laser to a fixed point and work from it. The rod bends in a plane that is perpindicular to the engine axis making the use of the laser that much more difficult. However, it should be possible if the rod was at BDC and you could hit it from both sides from a known reference point.

described a measurement taken in relation to the tops of the pistons to the top of the block.... with the head removed.

i have heard that they twist when they bend. and the twist i think is what causes the cylinder to wallow out and become oval in shape.

there is not a consensus on what causes them to bend but i think there is a consensus that they can be bent a very small amount... at least at first.

a couple of folks have reported bent rods on blocks with the factory "strengthened" rods on replacement short blocks, so that tends to make it seem possible that the problem is not weak rods.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

What if you get a set of rods made to your specification that would be way stronger than the stock ones.
I took apart the intake today and it was a little nasty so I am going to clean her up and do an EGRectomy, install a blocking plate, and put her back together. While I am at it, I found a couple of GPs not working so I have ordered all 6 so they will all be new. Much easier to replace while intake is off for a cleaning. This car runs so good that I want to do anything and everything possible to prevent what might cause rods to bend.
I still might pop off the pan and take a look at the rods and also to see if there are any mistery bolts lying around in the oil pan.

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