Calling all mechanics pro and amateur

I have a 49 Case SC, I bought it from an online auction a couple years ago. I didn't get a chance to inspect it before I won the auction at $770. The day I went to pick it up it wouldn't start so I had it towed to the shop near-by where I work. Upon looking at the fuel tank and line it was completely full of rust. After checking out a few home remedies to clean the tank and putting in a new sediment bulb assembly I was able to get it running. I had used it on the gravel lot at work and when I finished I noticed oil leaking out of the head gasket, so back in the shop it went to figure out that issue. When I took the valve cover and head off the pistons, rocker arms and valves were covered in burned oil. The valves and seats were in rough shape, in need of grinding and re-seating. I didn't stop there and took out the pistons to check the rings, one of the sets was completely seized in the grooves so I ordered a complete overhaul kit with rings and the necessary gaskets. When I got the head back with the valves cleaned and properly seated and putting the new rings on the pistons I began putting things back together. This is where things begin to get confusing to a greenhorn mechanic like me. I put the pistons back in the block and put them in their cylinder holes according to their number stamped on the connecting rod and on the piston head, tightening them to their prescribed torque specs from the Case manual I ordered. The issue is the crankshaft is difficult to turnover acting as if something is holding it from cranking like it should with a brand new battery. Even using the hand crank I struggle to turn it over. My uncle says you should be able to turn it over by hand. So my question is what would be possible issues that are resulting in a hard to crank crankshaft? Aside from the worst case being the shaft is bent, what are other possibilities? Sorry for such a long story to get to the actual question.
 
First did you put some sort of lube on the main and rod bearings as you where putting it together??. And also in the cylinders?? My self I use STP oil treatment but even then yes they can be hard to turn over and I have done a lot of engines and every one was hard to turn over but once started up did just fine for year if not decades
 
SO I have been there, kinda. Are all the stamped numbers facing the same direction on the piston rod assembly? If they are, is it possible you put them all in facing the wrong side? My story: I was helping my brother overhaul his 56 ford 6 banger. We had the first on in right, making sure the number on the rod cap and on the rod were both facing the right direction. After we had the second one in, we noticed the ford oval stamp on the bottom was on the same side on both caps. Since it was way easier to see we put it together with all the ford ovals lined up since it was much easier to see than the numbers. . We could not turn it over with a breaker bar with the head off. Took it apart. It turned out the stamp was not on the same spot on all the bearings. At least 2 were on the opposite side of the bearing. Turned them around the right way and the problem was solved.
 
I don't remember if I put any lube on the main and shaft bearings. That's my dilemma now to take the oil pan off and if possible turn the connecting rods around, but I was sure I put them in according to the instructions in the manual. The numbers were to be on the opposite side of the camshaft according to what the manuals list. Is this correct or should I try flipping them around? I have a brand new 650 CA battery on it and I barely got a half turn on the crank when it stopped completely like something was jamming it.
 
I've never been into a SC engine so cannot help with ow the rod should be but you do need to lube the rod and main bearings before installing them and yo should NEVER touch them with out some sort of oil on your fingers or yo can leave finger prints on them which can cause problems
 

Did you replace the rod and main bearings with new ones?

If so, I assume you verified if they were standard or an "undersize" and ordered the correct replacement parts.

I always install the crank and main bearings and torque them one at a time, verifying if the crankshaft continues to be able to turn easily, then move on to the pistons and rods, installing them one at a time, verifying that the crank only gets a LITTLE harder to turn as each is installed.

Once you get the oil pan off you can try move each connecting rod fore and aft a little (they have a few thousandths endplay) on it's rod journal to verify the bearing inserts aren't binding against the journals.

Same for the crankshaft, itself, it should move fore and aft in it's bearings for the few thousandths of endplay the crankshaft is supposed to have.
 
I don't believe I have even attained the amateur level of mechanic so with that in mind, here is where I would start. Did you plasti-gauge the bearings that you installed on rods and crankshaft? Something is way to tight.Remove the pan, check the direction of rods installation in accordance with the camshaft per the book/manuel. I do not recall just how the diagonal cut of the rod at the crank is positioned but the book does. If thats good it must be your rod and main bearing clearances. time to start over on bearing installation. Easy to get a LOT of dollars into these old tractors. good luck gobble
 
and to add to bob's post as that is the way its done , you might have been sold .002 undersize brgs. did you check the brgs on the back as it will be stamped into them. should have plastiguaged rods as each on was torqued. its not a long story as you gave a lot of info ? more than most do then want a miracle.
when I was 18 years old chev dealer sold me .002 under brgs. for my chev 250 cid. I did ask for standard and parts man says how many miles on it. it had about 100,000. he said you need .002 not standard. how was I to know. so in the end took those out, as engine would not turn over, and got standard ones and all was fine.
 
You will have to go back and remove the con rods from the crank. If you installed new main brgs they need a assembly lube on them. Once the brgs are lubed and torqued down you should be able to reach up and turn the crank by hand quite easily. If you can't, loosen the caps one by one until you locate the one causing the tightness and investigate from there. If the crank turns easily install the con rods one by one turning the engine as you go checking to see if any one is causing the tightness. I have learn to tap the con rod end fastened to the crank from side to side with a small hammer, checking to make sure it moves freely after assembly. All con rods should move side to side slightly and easily. Then there should be nothing causing the engine to bind up when all rotating parts are assembled. That is unless you have a tight piston and you would know which one is tight if you are checking movement as you go one by one. Personally I have never had a tight piston when installing new ones, but no doubt someone has. Rod.
 
Thanks guys for all your feedback. I did remove the oil pan to check the play in each connecting rod. 1,2 and 4 had no play in them so I loosened those cap screws but still couldn't turn the crank. I removed the caps completely and looking closer I do indeed have the rods and caps facing the wrong way so now I need to turn them around, hopefully without having to remove the head. I did lube the new bearings when I put them in the first time, and I'll make sure to lube them up again when I get things in the right way.

I appreciate your guys' advice. I'll let you know how things go and post some pics/vids of the SC when I get it running. Crossing my fingers.


Gene
 
I am familiar with the D series which has Babbitt bearings. It would be helpful to know if the S series also has Babbitt bearings or are they inserts?

Either way it seems that a little detective work is in order to fine out if only one rod bearing is tight. I assume the main bearings were not disturbed.

A procedure is to loosen the rod caps ONE AT A TIME and see which one frees up the crankshaft rotation. Loosen the two cap nuts of the rod about three turns. See if that frees up the crankshaft rotation partly or completely.



If the crankshaft rotation is still not free after loosening the first rod, LEAVE THE FIRST ROD NUTS LOOSE and repeat the procedure with another rod. Do the procedure on all four rods if necessary to determine which one (or ones) is dragging.

Whether the rods have Babbitt or inserts, they are machined at the factory with the cap assembled and the bolts tight. Then the assembly is "line bored" as an assembly. This means the rod and cap are a matching pair. This also means the cap has a right and wrong orientation to the rod when assembling onto the crankshaft . The orientation should be marked for the correct way to assemble it.

If the bearings are Babbitt, the assembly includes shim packs during line boring. This required an assembly procedure that uses "plasti gage".

If you had the main bearings apart, the same procecurte can be used to fine a tight main bearing---leaving all rod caps loose.
 
I had my SC apart about 10 years ago and I can not remember for sure, but the most engines i work on the stamped numbers on the rods go to the camshaft side of the engine.
 
Thanks Ron. I believe the cap bearings are inserts as they kind of snap into a groove on the connecting rod and cap. 1,2 and 4 rods had no play at all while #3 rod did have some play even with it installed the wrong way. I'll have to try maneuvering the pistons the right direction without having to take the valve cover and head off or busting/bending the connecting rods. Thanks for your additional info about the babbit style bearings and how the internal parts are machined.
 
Not to be a bummer for you BUT new sleeves and pistons adds a little more to the mix. The rods being reversed should be corrected but should not be causing the crank to bind up. They provide proper support on the powerstroke in the direction of rotation but still should move all the way around unless there are large rod bolts that hit the camshaft. That will make a metallic clunk sound when they hit.
Even though new, you should have run each piston oiled up through the mated sleeve without rings to check clearances. If you did not lube the sleeve orings one may have turned or ?rolled? when putting in the sleeves and actually pushes the sleeve in slightly and pinches the piston to prevent rotation.
Another issue is the piston rings. Did the bottom oil ring use really thin rings on the top and bottom? Several times I have had that type of rings slide out of the groove during installation and prevent movement.
Other issue is the backing of the bearing inserts. Make sure they are clean and rust free.
I recommend removing the head and pulling all pistons out and insert one at a time and torque down. Then turn motor over with hand crank several times to ensure free motion. Then install next piston and repeat. All that time and money would be ashame to ruin it. With coppercoat you could reuse the head gasket especially since it hasn?t been run to operating temperature and retorqued.
Just my thoughts
 
Did you thoroughly clean out ALL the crap in the piston grooves? All the way down to the metal? If not, that's one more thing you need to do.....
 
You say the numbers on the connecting rod and cap go towards the camshaft? That totally contradicts what it has in the manuals I've got, which say the numbers go away from the camshaft. I have the oil pan off, checked again as to which way I have the rods and caps facing and they are away from the camshaft side. Cylinders 1,2,4 don't have much play side to side and #1 seems to have an issue swinging freely on its pin like it might be rusted a bit or perhaps bent. I have the caps back on only hand tight, I've tried turning the crankshaft by hand as well as with the hand crank but struggling to move it easily. I may have to look closer at the size/thickness of the bearings to see if that's what might be the problem.
 
If you put new mains in it I would check to see if the caps are on correctly, if you have to , take the rod/piston units out and if it still turns hard loosen the main caps one at a time If it is like most engines the locks on the bearing shells are on the same side. If you have turned it you should be able to see a polished area on the shells that were binding, I would start from square one.
 
if your pulling the pistons again, don't forget to check the ring end gap which is .003-.004 for each inch of cyl. bore. and also the rings must be staggered from each other. your talking about a complete overhaul kit, so if this is the case that includes sleeves pistons and rings. unclear now as to what all you are replacing. if not the cyl's need to be honed.
 
I only replaced the piston rings, valve, head, oil, manifold, water pump gaskets. I did hone the cylinders, left in the old sleeves, rod and main bearings. I have taken out the rod bearings that were in there to look at their numbers and condition. I tried looking for bearings online with minimal success of what might fit my tractor, the numbers on the old bearings are 07809AB D.A.B. 2-65. So I'm guessing these bearings were made in Feb of 65 from reading other posts on here.
 
Gene,
There is a spec on how much the gap should be at the ends of the ring after it is installed. Typically the spec for this gap is .010--.025

If you are unaware, the procedure is before putting the ring onto the piston, put the ring into the cylinder bore that it will be installed in. If you reused the old sleeves measure the gap at two positions both high and low because a used sleeve might have a slight taper.

Use a feeler gage to measure the gap. Carefully file one end of the ring if the gap is too little. No problem if the gap is over spec. If it is under spec, the temperature expansion of the ring might cause the amount of gap to want to go negative. This would probably cease up the engine at idle or probably break a piston if under load.

Did your SC smoke any amount the little bit you used it?

Hoping the overhaul turns out good.
 
I dug my old manual out and looked in it and you are correct, it says to turn them away from the cam. Like i said it's been a wile sense I been into one.
 

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