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1Ton_tommy #1459577 Thu Jul 21 2022 04:36 AM
Joined: Jul 2014
Posts: 406
Roadworthy: I once put dry sleeves in a 40's era I-H tractor. They were lots less expensive than new 4-ring pistons as I recall. My labor time was almost free in those days as it again is. I Welded a bead up the sleeve to shrink them and drifted them out. I used dry ice to install them. R&R was an all-day job for 4 cylinders. Wet sleeves on Cummins is much easier.

So my pistons are sent off to the machine shop for knurling and the crankshaft is installed in the block. I shimmed the main bearings to get 0.0015 on the rear main and 0.002 on the others. I have a set of new rod bearings but I'm short on tapered shim stock so I'm hoping I don't have to shim them to get 0.002 clearance. The crank is round but is worn 0.001 or so.
I could probably shim a couple of them but that's all. My local parts man said he doesn't deal with his engine guy anymore over some long ago argument so he can't get tapered shim stock. More news when I get my pistons back and UPS brings me more parts.

51 3800 PU, 62 261 (w/cam, Fenton headers, 2 carbs, MSD ign.), SM420 & Brown-Lipe 6231A 3spd aux. trans, stock axles & brakes. Owned since 1971.
1Ton_tommy #1459604 Thu Jul 21 2022 12:42 PM
Joined: Nov 1995
Posts: 5,599
Unrepentant VW Lover
Tommy, if you still have everything apart ... I *highly* recommend you send your rods to Jerry for reconditioning. Its easy to check to see how far out of round they may be and I can personally vouch for Jerry's expertise at this. You ought to take him up on his offer!

By the way, I watched him knurl my piston skirts -- it was pretty neat ... In a Mennonite machine shop, by a window (for light) on an ancient lathe powered by belts from a 6-71 Detroit. Talk about "Old School" wink


"If there are no dogs in Heaven, then when I die I want to go where they went."
Will Rogers

'49 Chevrolet 3804
'73 IH 1310 Dump
'14 Ford E-350 4x4 (Quigley)

1Ton_tommy #1460341 Tue Jul 26 2022 09:53 PM
Joined: Jul 2014
Posts: 406
So John, is that Jerry's usual shop? I'd had thought being that close to Nashville and all those guitar amplifiers some of that electricity would filter out to the countryside. I mean we even have electricity here and it's an hour's drive to the nearest BPA dam. Granted it took a shooting war to get BPA power up the valley.

Along about 1968, I got a part for my 66 Pontiac machined by an old fellow in Leominster, MA. He was 90 then and told me his father had built the machine shop, starting by hand-building a lathe for which he had the headstock cast in Boston and hand built the rest. From that he used the lathe to make the rest of the tools, all driven from above by flat leather belts running on pulleys of various sizes. It had been powered by wood-fired steam and eventually coal and after WWI they converted to oil. When I saw it the power was from a huge electric motor that you could see into and watch the brushes arcing. It was like the history of the American industrial revolution in one shop.

Today, a lifetime later, I came in for lunch and it's too hot to go back to work so I'll write up the latest on my 261 overhaul. It got to a hundred yesterday and today is supposed to be 106. My machinist is only working till 3PM these days because he's got no air conditioning. Neither do I. So yesterday morning I drove to the neighboring town to collect my knurled pistons and my rods. My pistons now have a nice Perfect Circle logo knurled into the skirts.

I had checked the con-rod bores and could tell they were round to 0.0005 but with the heat I couldn't tell how big they were. My Jo-block is as hot as everything else -- hardly room temperature. Anyhow the machinist keeps his jo-blocks in the fridge and knows what the mic should say on a refrigerated Jo-block. A Jo-block is a piece of metal of known size used to calibrate micrometers and such. Anyhow, he had checked the rods and said they were right on and still straight and he didn't charge me for that. The piston knurling was $10 each and I though that was reasonable.

He was of the opinion that knurled pistons should be fitted tighter than I ever have, basically filed down so you can just get them in the bore and they'll seat themselves. That scares me. These are solid skirt pistons destined for heavy-duty truck work and I've replaced a few Cummins sleeves and pistons when the drivers weren't watching the pyrometer and stuck them. Those are the same guys that pop head bolts. Sometimes you can head that problem off because you can see antifreeze stains on the block from the heads bouncing up and down. Write a little note and put it in their box with their dispatch so they know you're watching. But I digress...

I compromised and set the pistons to a stiff pull on a 0.002 feeler. Hopefully they won't slap and they won't stick. Oil catches in the knurl so oil control is better and you can fit them tighter. He did a good job. I told him what bore sizes I had and numbered the pistons. In the end it only took a couple whacks with a file to set the clearance. That was yesterday.

51 3800 PU, 62 261 (w/cam, Fenton headers, 2 carbs, MSD ign.), SM420 & Brown-Lipe 6231A 3spd aux. trans, stock axles & brakes. Owned since 1971.
1Ton_tommy #1464444 Mon Aug 29 2022 07:07 PM
Joined: Jul 2014
Posts: 406
A month has gone by since I last posted. The 261 is alive and well and powering my 3800. I will have to change my signature to match. When I last posted I had fitted the pistons. Most of the reassembly went without incident. However it had to wait for me to pull the 235 out of the pickup to get some needed parts. I took the head I'd had gone through about 40,000 miles ago and the Crower cam, lifters pushrods and rockers and the dual-carb intake and Fenton exhaust manifolds . I pulled a few exhaust valves and checked the seats and stems. All was good. No stem wear or guide wear with bronze guides and PC umbrella style seals.

I drilled the 235's 848 head for the 261 block with a 3/8 hand-drill motor, duplicating the 12 deg. angle. One thing I noticed was that the combustion chamber volume was noticeably smaller on the 235 head than the 848 head that came off the 261. When I had the 235 head done I was concerned with valve/piston interferance and cautioned the machinist about milling the head. He said he only took a skim cut to make sure it was flat. I wonder if the late 235 heads were factory milled to get 8.25:1 compression. So now I calculate that I have 9.2:1 compression and so far no pinging on 87oct. gas in hot weather. I used the 235 distributor whose gear matched the cam and set the timing to 5 deg advance. When installing the cam with a new gear set I came up with 0 backlash, which bothered me but it wasn't negative and I didn't know what to do about it anyway. Both are Melling gears for that application.

While on the subject of the head, the head gasket that came with the Felpro kit is composite. I'm used to installing copper-sandwich gasket with spray-on Copper Coat cement or aluminum spray paint. I've never had a head-gasket failure and hope I never do. I've always gone a few hundred miles before re-torquing the head. Any opinions on this with a composite gasket? Sooner perhaps?

I found a Franz oil filter on E-bay and put that on in parallel with an external, spin-on kit from Deve. For anyone following in my footsteps, this combination of external full-flow filter and Fenton dual exhaust creates a plumber's nightmare. There are many pipe connections and I felt they must be done after the engine is in the frame lest I risk breaking some pipe fitting or block casting when swinging the motor. It is now in but I had to chase a leak that required some disassembly after the fact. If doing this, use pipe dope AND tape. I used yellow gas tape on the repair. there are some 90 deg. joints where you have to decide whether to risk splitting a fitting if you take a whole additional turn or leaving it a little too loose. I ended up routing the pressure line behind the front exhaust pipe rather than outboard because to go outboard of the exhaust pipe puts the oil pipe too close to the hot exhaust pipe while still clearing the steering box. I wonder if the frame rails on a 1-ton are narrower at the front. I believe Deve mocked up his kit on a 1/2-ton chassis. BTW it's a nice kit using stainless pipe and fittings and AN swivel fittings for the braided-stainless hoses. I only had to add additional tee for the Franz filter.

I also installed a coolant filter bracket I scrounged from an old Cummins marine diesel. I used the side motor-mount bosses on the block. One reason I did this was because both engines had so much sediment in the back left corner that the block-drain was plugged despite being flushed every couple of years. And it was a bit of the chore to mechanically remove the sediment with a pressure hose and a screwdriver through the various holes in the block. Hopefully, that won't happen again with a new Wix filter element for an up-to 4 gallon system.

So now a long job is done, road-tested and all that's left is to wash the truck of many greasy hand prints.

51 3800 PU, 62 261 (w/cam, Fenton headers, 2 carbs, MSD ign.), SM420 & Brown-Lipe 6231A 3spd aux. trans, stock axles & brakes. Owned since 1971.
1Ton_tommy #1464481 Mon Aug 29 2022 10:18 PM
Joined: Dec 2008
Posts: 1,785
Thanks for the heads up.
However, w/r/t "Crower... rockers":
No 235 rockers have been made in the last 50 years, and not by Crower.
The rockers listed by cam companies are Gen-3 stud-mounted and completely different than what is needed.
Picture or listing of what you used?

1Ton_tommy #1464489 Tue Aug 30 2022 01:00 AM
Joined: Jul 2014
Posts: 406
Re rockers: The rockers are the factory ones associated with the head that came off the 235. Perhaps I missed a comma in that sentence of my report. They were in better condition than the 261's rockers. The pushrods are tubular ones from Crower. I was disappointed not to use the valve rotators off the 261 but they were in poor condition and perhaps not needed anyway. The lifters came from Crower at the time I bought the cam and were properly radiused to match the cam profile per Crower's instructions. FWIW the cam and lifters showed no wear in 80,000+ miles.

51 3800 PU, 62 261 (w/cam, Fenton headers, 2 carbs, MSD ign.), SM420 & Brown-Lipe 6231A 3spd aux. trans, stock axles & brakes. Owned since 1971.
1Ton_tommy #1464493 Tue Aug 30 2022 01:18 AM
Joined: Dec 2017
Posts: 1,183
I used the composite gasket last year on my 261 after using copper gaskets for 45 years. I had the same concerns as you. In the end, perfect. I have not even bothered to retorque the head. And my motor uses high compression forged pop up pistons. Still no issue and the motor has at least 40 runs down the drag strip over the last two years.

Last edited by Dragsix; Thu Sep 01 2022 08:59 PM.

1Ton_tommy #1464495 Tue Aug 30 2022 01:47 AM
Joined: Dec 2008
Posts: 1,785
Oopps, my bad, jumping to conclusions.
Of course, I should have suspected as much.

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