Piston rings and refreshing an engine.

[Jeffry Cassel]

They cannot wear as there is no movement between the bolt and the bolt hole. Any play could allow movement, which, I am sure you will agree, would not be a good thing. To paraphrase P T Barnum ' You will never get very far by overestimating the intelligence of the average grease-monkey.' I can easily see some doofus with a drill or rat tail file making it easier to install those bolts!!

[PackardV8]

I see a disaster coming on. In short, take you motor to a reputable machine shop and have them do the job. You are changing parts, wanting to reuse piston rings, not going to hone the cylinders, rod bolts, balancing, etc. It's a major hassle to have to remove and rebuild it again, and very embarrassing, simply because you are cutting corners. Yeah, I might sound harsh, but all this runaround is getting old. The job would be done by now, rather than all this back and forth. I ALWAYS have the engine assembly balanced. I ALWAYS use NEW piston rings. I ALWAYS hone the cylinders, at the least. I ALWAYS properly mic the cylinders and pistons to make sure they are in spec. I ALWAYS check the ring lands if I am reusing the pistons. I ALWAYS have the rods checked and resized if they need it. Rod bolts are cheap. Then there's the heads; ALL the parts need to be properly inspected and replaced where needed: Valves, valve guides, springs, seats, which should have hardened ones installed on the exhaust at the least. And hen there's the cam/lifters/bearings, if the block needs any work, have new cam bearings installed. Hot tanking (rarely done these days) ruins bearings. If the cam/lifters are reused, be absolutely exact as to which goes where, same lifter on the same lobe. Just one mixed up will kill the cam real fast. And the crank: I ALWAYS mic it myself, or have it checked, and if it's good, have it polished and rechecked. If you get to the point of installing the pistons/rods, plastic gauge every rod and main. These are ALL things that need to be done for a good job, and end up with a good running motor that will last. I have been doing motors for well over 50 years, for customers and myself, with great results. I retired 10 years ago and still get calls because people can't find someone to do the job right, not cut corners, or have returns to fix what were scrimped on. Do it once, do it right, and enjoy it. Can't afford all that? Can you afford to do it yet again, costing even more money? Start saving your money to afford the job, or, do it right and do it ONCE. Or, I direct you to the first sentence I wrote.

Yes, I agree and we don't do patch jobs either.

However, in defense of the OP, he had the motor rebuilt some years back and it only ran 200 miles. At present, he is only thinking of swapping in reconned rods with ARP bolts. I don't see problems or shortcuts he'll regret.

jack vines

[IndStudenut]

I know on the champion six the oil hole on the rod is drilled offset and the piston is mounted on the rod a certain way and you cannot mix odd numbered rods with even numbered rods. Is that the same case on the V8 motor or did Studebaker get away from that concept. I made that mistake on a six years ago messing with a Stude motor and not having the manual... had a busted rod and a broken camshaft as a result. It may not apply here...... but definitely a manual is a must. Or take real good pictures and make notes of how it came apart to get it back together the same way.

[yeroldad]

I see a disaster coming on. In short, take you motor to a reputable machine shop and have them do the job. You are changing parts, wanting to reuse piston rings, not going to hone the cylinders, rod bolts, balancing, etc. It's a major hassle to have to remove and rebuild it again, and very embarrassing, simply because you are cutting corners. Yeah, I might sound harsh, but all this runaround is getting old. The job would be done by now, rather than all this back and forth. I ALWAYS have the engine assembly balanced. I ALWAYS use NEW piston rings. I ALWAYS hone the cylinders, at the least. I ALWAYS properly mic the cylinders and pistons to make sure they are in spec. I ALWAYS check the ring lands if I am reusing the pistons. I ALWAYS have the rods checked and resized if they need it. Rod bolts are cheap. Then there's the heads; ALL the parts need to be properly inspected and replaced where needed: Valves, valve guides, springs, seats, which should have hardened ones installed on the exhaust at the least. And hen there's the cam/lifters/bearings, if the block needs any work, have new cam bearings installed. Hot tanking (rarely done these days) ruins bearings. If the cam/lifters are reused, be absolutely exact as to which goes where, same lifter on the same lobe. Just one mixed up will kill the cam real fast. And the crank: I ALWAYS mic it myself, or have it checked, and if it's good, have it polished and rechecked. If you get to the point of installing the pistons/rods, plastic gauge every rod and main. These are ALL things that need to be done for a good job, and end up with a good running motor that will last. I have been doing motors for well over 50 years, for customers and myself, with great results. I retired 10 years ago and still get calls because people can't find someone to do the job right, not cut corners, or have returns to fix what were scrimped on. Do it once, do it right, and enjoy it. Can't afford all that? Can you afford to do it yet again, costing even more money? Start saving your money to afford the job, or, do it right and do it ONCE. Or, I direct you to the first sentence I wrote.

[PackardV8]

Jeffry, do enough Studebakers and you'll have handfuls of rod bolts. If they were ever supposed to be snug fit, after fifty-plus years and 100,000 miles, many aren't any longer. No, they weren't drilled out; just the way Studebakers are.

jack vines

[Jeffry Cassel]

I've never met a rod bolt that would simply fall out. They should be snug so that they would need to be pushed out with a thumb or even tapped out with a tack hammer. If there is any play at all between the bolt and the bolt hole, I would not use that assembly. Some one might have drilled out that hole and with a perfectly good motor having been completely dismantled, nothing is out of the question. Aggrevatin', ain't it.

[oilnsteel]

Which brings to mind a story -- I can hijack my own thread, can't I? In my mis-spent youth, I worked in an an automotive machine shop. This happened before my time, but my boss loved to tell the tale. A customer brought in the cylinder head to an old 216 Chevy, the one with the dippers on the rod caps to lube them. The customer was re-ringing the car,
and had promised it to his customer by 4:30 that night. The boss reground the valves, and had the head delivered by 10 AM.

Around 2:30, the phone rings, and its the customer, and he is frantic, and ugly mad!

You ground the valves, and you screwed up! There's no compression on number 3! Not one d**n pound!

Well the boss was sure he hadn't made a mistake, and went over to the garage. It was sort of a dirtball place, every bench covered with parts, tools, and rags.
He couldn't figure out what was wrong, either, so he moved some stuff out of the way on a bench so he could sit up there and ponder.

There he found number 3 piston and rod assembly, all oiled up and ready to be installed.

The customer was in such a hurry, he got ahead of himself.

My boss went back to the shop, and got another gasket set, and helped him get the car finished on time.

I think there may be more than one lesson there of some sort.

JT

[PackardV8]

The rods are numbered. As long as the assembly (rod and piston and rings) are kept together, no need to mark them.

As he mentioned earlier, he's removing the pistons from the rods and replacing the rods with another set, but yes, as long as he does them in order, matching one to the other, he's good. But we all in the enthusiasm of the moment have forgotten what was supposed to go where.

jack vines

[64studeavanti]

The rods are numbered. As long as the assembly (rod and piston and rings) are kept together, no need to mark them.

[PackardV8]

Yes, marking the piston to the cylinder is good science. Whether it makes a difference depends on how close to the same diameter were your old school pistons and if your machinist made any attempt to finish hone the cylinders to match them.

No, it's not going to make a difference with today's pistons. They're CNC machined and almost always exactly the same diameter. We measure anyway; trust, but verify. As to piston rings, they rotate while running and theoretically there's always a film of oil to prevent the piston skirts from touching the cylinder wall.

jack vines

[IndStudenut]

Jack V. - Would it be wise for him to make sure that the same piston and rings go back in the same cylinder? Or would that make a difference. I would be inclined to mark what piston came from what cylinder and put it back together the same way.

Just me tho.

[PackardV8]

Pistons and rings should not have a problem with being removed and reinstalled.

jack vines

[oilnsteel]

Joe, the majority of the bolts will fall out of the rod when upside down. I'm guessing they have a couple of thousandths clearance. More than what I've found in other Stude
engines, which seem to be a light slip fit.

I'm going to change the rods with the other set I mentioned. Jack, I have a precision scale, and will take your's and Bezhawk's advice and match the weights of the pistons and rods.
I cannot bear the thought of doing something substandard in one of my beloved Studebakers, and want Stanwood Sparrow's ghost to smile down on me.

One other thing- will any problems come from removing and replacing the pistons, as far as the rings are concerned? As honing marks are still in evidence on the cylinder walls,
will the rings continue to seat, and not resent the disturbance?

Thanks, JT

[PackardV8]

Yes, Studebaker rod bolts are not a tight fit in the rods, so there's nothing inherently wrong there. Change them to those with ARP if you choose, especially since they have resized big ends. (We do this on all builds, even if original bolts are reused.)

Yes, it's worth the effort to at least weight match the pistons and rods (big and small ends separately)

Yes, an engine which has the crankshaft spin balanced will run more smoothly.

jack vines

[JoeHall]

"But, the rod bolts do not fit tightly. When the cap is removed, most will fall out on their own weight." Are you saying the cap falls off, or the bolts fall out of the rod if the piston & rod assemble is turned upside down? Since you rebuilt the engine yourself, 30+ years ago, did yo reassemble it correctly? If bearing clearance is OK, I'd think the rod bolts are OK as is, whether it's the bearing caps you are talking about, or the rod bolts. I'd spin the oil pump long enough to build oil pressure on the gauge, then start the motor and run it in. IMHO, you are wasting time trying to 'fix' something that may not be broke. OTOH, if you have serious doubts about your work in 1990, then maybe just e-do everything. Only you know whether that's really needed or not. Good luck.

As for balancing the rotating components on the motor, I done it both ways, and cannot tell any difference between balanced and unbalanced. Unless a rod is an 'odd ball' among a set, i.e. someone replaced one with NOS yesterdecade, and the balancing pads are untouched, any weight differences will likely be negligible. Be careful of 'mission creep'.