256 vs 268 engine

[sander]

I have 755b backhoe, which came with 268 engine (?). Earlier (750, 755, 7500) came with 256 engine (?). Other than stepped studs & different Inj pump whats the
difference between the engines, are the torque specs the same. I see the 268 was used in 7610 tractor (?). Is bore/stroke the same on 256/268 engine. I see the 7610
was sleeved engine where the engine in my 755B is not (?). My engine has to be sleeved as its got a leak in cylinder wall. THANKS

 

[Bern]

The 268 has a longer stroke, 4.4 vs 4.2 inch, and a few more ponies. Neither engine came from the factory with stepped studs or sleeves - these engines are designed as parent bore. Torque specs are largely the same, although there are some date-dependent differences with the head bolts and cam idler gear mount.

 

[Sean in PA]

Is bore/stroke the same on 256/268 engine

They are both 4 cylinder engines and they have different displacements, so they could not have both the bore and the stroke be the same, otherwise they would have the same displacement. They do both have a 4.4" bore, but the stroke is 4.2"on the 256 and 4.4" on the 268.

All of the models that you mentioned had the Turbo versions of those engines, and the268T has about 10 more hp than the 256T, but I don't have any reference documents that mention the torque. Both of those engines have more than enough hp and torque to fully stress all of the rest of the mechanical systems, transmission, rear axle, and loader and backhoe hydraulics.

Pinholes in the cylinder walls were common if a proper anti-cavitation coolant additive was not used. They were parent bore as Bern said, and they were designed to be bored for sleeves if necessary. Once you get it sleeved, make sure that you use a coolant that has the anti-cavitation additive already in it, or mix it in yourself.

 

[Destroked 450]

Have your block sleeved and keep the 268, the torque difference is very noticeable

 

[sander]

Thanks for the info! The Ford Service Manual for the 755, 755A 755B doesnt list the stroke for the 268 let alone make mention of the 268 engine. So the 268 is a square (b & s) engine.

 

[Bern]

According to the parts book, the 755 was produced between 1978 and 1983. The 268 engine came out in 1980. If your repair manual is dated before 1980, that would explain why you don't see any mention of it.

 

[Check Break]

All of the models that you mentioned had the Turbo versions of those engines, and the268T has about 10 more hp than the 256T, but I don't have any reference documents that mention the torque.

Here's some torque info for the BSD-s. Should be close to the originally installed engine.


This post was edited by Check Break on 03/08/2023 at 02:17 pm.

 

[Check Break]

Problem with picture upload.

 

[Check Break]

Pics won't upload, so ...
256 Nat. 203lbs 256T (No data.)
268 Nat. 219lbs. 268T 278lbs