austinsailor Posted January 3, 2011 Report Posted January 3, 2011 Last summer I bought an old motor out of a truck in a scrapper's yard. I figured for $50 I could get something useful from it. PTO was gone on the transmission, but the rest of that was there as well. A couple spark plugs were broken, so I expected some water had gotten in a couple cylinders. This was from about a '49 or '50 1 1/2 ton or maybe 2 ton. Reman engine with a tag riveted on the serial number boss, nothing under it, and the tag was mostly missing. Bottom line, no telling what it was. Turns out water only got into #6, it's stuck bad. Rest of the block, crank and cam look good. Got to get the crank out, but the bearings look good, no sign they are undersized. Very little ring ridge, might make a fine core. Strange thing, though. 3 of the 4 pistons I got out have one side broken out, the pieces fell out when I took them out, and the rings fell apart. There is no doubt why it was parked. Cylinders look fine, though. Oh, stroke is 4.5", bore measures something like 3.4", hard to be accurate with the tools I have. I'm guessing it's the standard 251 truck engine. Now I'll take a drill to #6 and reduce it to rubble until it falls out. This could end up being my hot rod engine I'd like to build. I also have a '48 Desoto motor to chose from, but this one is bigger, so might be the way to go. Shaved head, reground cam, headers and dual carbs - how wild can I get? Quote
austinsailor Posted January 3, 2011 Author Report Posted January 3, 2011 ok, I need some direction before I screw something up. The flywheel has 8 bolts, nuts on the motor side. 5/8", can't get a standard box wrench on them, an open end feels like it'll round them off before turning. I can grind a little off a box end, but first, the nuts have small notches on the middle of the flats, similar to brass fittings that are left hand thread. I think that is showing they are hardened, not left hand. Correct? any hints before I tackle it tonight? oh, everything is usable, so it'll probably go to the machine shop soon. Quote
Merle Coggins Posted January 3, 2011 Report Posted January 3, 2011 I believe you are correct in assuming that the notch indicates a hardened nut. They are NOT LH thread. I can only suggest that you use a good quality open end wrench to avoid jaw spread and go at 'em. My Fluid Drive setup has the same arrangement. They are 5/8" as I recall. Quote
Don Coatney Posted January 3, 2011 Report Posted January 3, 2011 Not all grade 8 nuts have the notch as Merle pictured. The ones I used have 8 dimples on the face. Size is 7/16" X 20 TPI. Also the bolts must have a shoulder long enough to extend through the flywheel and into the the crankshaft flange. Quote
austinsailor Posted January 3, 2011 Author Report Posted January 3, 2011 thanks. I'll attack them tonight and I'll bet they'll come off. at first glance this appears to have a much bigger clutch and pressure plate. Probably the reason for 8 bolt instead of 4. I'm also guessing this won't fit in a car bellhousing. A bigger clutch would be great, but this probably wouldn't work Quote
greg g Posted January 3, 2011 Report Posted January 3, 2011 It might be worth the expense to get a 6 point box wrench and grind it doen to fit over those. You might be lucky and get an open end to get them all loose, but with my luck i would look an inexpensive box and work it to fit. Quote
Dodgeb4ya Posted January 3, 2011 Report Posted January 3, 2011 I have always used a regular combo wrench-box-open end type. But then I found the correct 5/8" and 11/16" FD wrenches, makes it sooo easy. Bob Quote
Merle Coggins Posted January 3, 2011 Report Posted January 3, 2011 Awesome Bob. I never would have thought such a tool existed. It sure makes sense that they'd have special tools for 'em back then though. Merle Quote
Don Coatney Posted January 3, 2011 Report Posted January 3, 2011 I have always used a regular combo wrench-box-open end type. But then I found the correct 5/8" and 11/16" FD wrenches, makes it sooo easy.Bob Cool tools. With the length of that tool I could twist off the bolts. You should post these in the tool thread. Quote
austinsailor Posted January 4, 2011 Author Report Posted January 4, 2011 Got it off, didn't mash off any corners. It was close, but I did get them. Got to get a big socket tomorrow to remove the pulley on the front, but it's pretty well apart. Question: Are the exhaust valve stems usually quite a bit bigger than intake? On other engines I've worked on they were usually similar. I suspect that, this being a truck motor, they are sodium filled. Not sure what needs to be replaced and what is usable yet, but assuming I need new exhaust valves, and assuming these are sodium filled, can I just replace the guides with the other type? Or, should I be buying a set of these: ebay # 360122781944 They look to be the ones I have. Quote
Dodgeb4ya Posted January 4, 2011 Report Posted January 4, 2011 Cool tools. With the length of that tool I could twist off the bolts. You should post these in the tool thread. I will post pics of them Don. The tools are stamped No Warranty because of breakage just as are 1/2"-3/8" socket adaptors ect. Bob Quote
Dodgeb4ya Posted January 4, 2011 Report Posted January 4, 2011 If the engine is a heavy 2 ton or heavier 2-1/2 tonner .437" sodium exhaust valves were installed some with bronze guides. You want that set up! I have them in my 265 1ton. Bob Quote
austinsailor Posted January 4, 2011 Author Report Posted January 4, 2011 (edited) Not sure what it was - here's a picture. Of course, it was a motor from somewhere else, remanufactured. Rods are ground to .030 under. Not sure yet if it needs turning now, but I recall from many years ago that over .030 you are getting past the hardened area. should I be worried? I have a Desoto that I should be able to get a crank out of. Just checked the valves .437 it is. Oh, another thing. The transmission seems in good shape, I expected to find top gear to be 1:1. It may be in there somewhere, but trying it on the ground every gear I found was undergeared, nothing was 1:1 that I could find. Granny seemed to be far right, and back, reverse far right and forward. My 47 3 ton is the same, with high at center and back. On this one, that is less than 1:1. And I had hopes of finding it was an overdrive, which I understand a few were made with. Edited January 4, 2011 by austinsailor Quote
Dodgeb4ya Posted January 4, 2011 Report Posted January 4, 2011 Well Gene, If the drums are 6 lug, thats a 2-1/2 tonner J or K series. I see it's a 2 speed rear axle. The trans is a 5 speed and if not a OD tarns will have a R stamped at the rear trans drain plug. If it's a OD trans it will have a OD stamped at the drain plug. OD transmissions are really really rare to find in the old Dodges. I do have one in my 51 JA dodge dump bed truck. Bob Quote
austinsailor Posted January 4, 2011 Author Report Posted January 4, 2011 You are pretty observant - I guess you saw the controller on the firewall. I do believe it had 6 lugs, although I am not 100% sure. Not long after I took this picture we ripped the sheet metal off and yanked the drive train apart to get the motor and tranny out. I got the doors, but the rest of the cab was too beat up to be of much use. I did hate to leave the rear end there, but there was only so much I could find a use far and I already had a COE and a 53 half ton on the trailer. Such is the life of a scavenger/picker! I did salvage a fresh air heater and an electric wiper setup out of it. Not much else was usable. I suspect the rest is now on the way to China. I got lucky on the motor. I gave $50 for it, hoping to salvage a few parts from it, but it looks like it's going to be a good one. The head is still questionable, but the block and crank are good, so I did ok. I'll check for the stamping on the transmission tomorrow. Thanks for the pointer. Should the pattern be: 2 4 R N 3 5 1 ???? Quote
Dodgeb4ya Posted January 4, 2011 Report Posted January 4, 2011 You are pretty observant - I guess you saw the controller on the firewall.I do believe it had 6 lugs, although I am not 100% sure. Not long after I took this picture we ripped the sheet metal off and yanked the drive train apart to get the motor and tranny out. I got the doors, but the rest of the cab was too beat up to be of much use. I did hate to leave the rear end there, but there was only so much I could find a use far and I already had a COE and a 53 half ton on the trailer. Such is the life of a scavenger/picker! I did salvage a fresh air heater and an electric wiper setup out of it. Not much else was usable. I suspect the rest is now on the way to China. I got lucky on the motor. I gave $50 for it, hoping to salvage a few parts from it, but it looks like it's going to be a good one. The head is still questionable, but the block and crank are good, so I did ok. I'll check for the stamping on the transmission tomorrow. Thanks for the pointer. Should the pattern be: 2 4 R N 3 5 1 ???? Depends on if it is a H-Duty spur gear 5 spd trans- with or W/O OD or a lighter duty syncro trans with or W/O OD. Kinda confusing-I know. I can't even remember my OD shift pattern as I use it around my property and never on the road. Your pattern is correct for most of the dodge 5 speeds though. Bob Quote
austinsailor Posted January 5, 2011 Author Report Posted January 5, 2011 Got it torn down the rest of the way. No more big surprises. Here's the tally: 4 broken pistons, broken rings on 5 of them, one piston stuck due to water in the cylinder. I scored that cylinder getting the piston out, but my machinist says that is no big deal at all, he'll sleeve it, does it all the time. Crank .030 under on rods, .020 on mains, all journals look fine. May or may not need turning. Timing chain is very loose, but no surprise, since the little oil tube that lubs it is stopped up. Cam looks good, lifters look good, I think it needs new valve guides, but my machinist will know for sure. He tells me about $500 to do all the machine work to put it in top shape, then I need a bunch of parts. I may drop it off soon and see what he thinks. I wasn't able to find any markings on the transmission, but it's not a big deal at this point as it won't be used anytime soon. If it had happened to be an overdrive unit, I would try to fit it into my '47 3 ton to get a little more highway speed, but it's not a big deal. I can drive it 45 mph and piss people off - what can they do? It's too big to play chicken with, so they'll just have to deal with it! Quote
austinsailor Posted January 10, 2011 Author Report Posted January 10, 2011 Does this look like a reasonable parts list and cost estimate for my old truck engine? What am I missing? 251 truck engine rebuild list Machine work $500.00 Parts needed Cost Gasket set $100.00 Pistons $250.00 Rings $65.00 Cam grind $150.00 Bearings Rods $80.00 Mains $80.00 Water pump $50.00 Carb setup $1,000.00 ( George Asche 3 carb setup) Timing gears $25.00 $35.00 Timing chain $55.00 Valves Exhaust $54.00 Intake $75.00 Cam bearings $40.00 Water dist tube $65.00 Oil pump $90.00 Freeze plugs $15.00 Total $2,729.00 Quote
Young Ed Posted January 10, 2011 Report Posted January 10, 2011 Id say thats pretty close. My stock rebuild was just under 1600 and if you take out the cam grind and the carb setup you're right about there. Quote
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