655d sheared oil pump.

[dannyidp]

I have been Building engines a long time and I have never seen this happen. I'm just lucky I caught it in time.

 

[Janicholson]

I have seen it when a pump got a sliver of metal in it, and when General motors Hex shafts wear ot twist up/fail

 

[Fritz Maurer]

Looks like it’s been cracked a long time. Possibly improper heat treatment and/or a crack started in that rough-azz finish.

 

[used red MN]

I have seen it when a pump got a sliver of metal in it, and when General motors Hex shafts wear ot twist up/fail

Hey now, I have seen some automotive Fords that rounded off the hex oil pump drive as well.

 

[Janicholson]

Hey now, I have seen some automotive Fords that rounded off the hex oil pump drive as well.

Agree, just never happened to mine. Jim

 

[NDIHC]

Used to be common on Ford V8 gas engines with the hex oil pump drives. Especially in the winter when the oil got really thick.

 

[NDIHC]

I have seen it when a pump got a sliver of metal in it, and when General motors Hex shafts wear ot twist up/fail

Which GM used hex shafts? Trying to remember if maybe Olds or Pontiac? I just can't remember. Chevy used the slotted round shaft. Ford was hex.

 

[used red MN]

The more I think about it I am also wondering which GM engines had a hex drive? I know small and big block Chevys had tang drives. I know 250 and 292 sixes had tangs, I know Buick with the oil pump in the front timing cover had tang drives as well. I am somewhat sure the Stove bolt sixes had a tang drive. So that leaves the same ones you came up with, Olds and Pontiac plus Cadillac. I also want to say some Chrysler Corp. engines used hex drives.

 

[kencombs]

Used to be common on Ford V8 gas engines with the hex oil pump drives. Especially in the winter when the oil got really thick.

Yep, especially when the old thing was burning oil and the owner
'fixed' it with 40 or 50w oil at zero or so. I think I recall Ford increasing the size of the hex sometime in the 60s
'cause it was so common..

Also have seen it happen with the old Y blocks when someone put in a high volume pump with a higher relief spring.

 

[kencombs]

Used to be common on Ford V8 gas engines with the hex oil pump drives. Especially in the winter when the oil got really thick.

Yep, especially when the old thing was burning oil and the owner
'fixed' it with 40 or 50w oil at zero or so. I think I recall Ford increasing the size of the hex sometime in the 60s
'cause it was so common..

Also have seen it happen with the old Y blocks when someone put in a high volume pump with a higher relief spring.

 

[used red MN]

Yep, especially when the old thing was burning oil and the owner
'fixed' it with 40 or 50w oil at zero or so. I think I recall Ford increasing the size of the hex sometime in the 60s
'cause it was so common..

Also have seen it happen with the old Y blocks when someone put in a high volume pump with a higher relief spring.

Any idea how you make that double reply? Are you double-clicking the “Post Reply” button?

 

[kencombs]

Any idea how you make that double reply? Are you double-clicking the “Post Reply” button?

Yep. Forgot I'd already hit it. Most forums don't allow that.

 

[Janicholson]

The more I think about it I am also wondering which GM engines had a hex drive? I know small and big block Chevys had tang drives. I know 250 and 292 sixes had tangs, I know Buick with the oil pump in the front timing cover had tang drives as well. I am somewhat sure the Stove bolt sixes had a tang drive. So that leaves the same ones you came up with, Olds and Pontiac plus Cadillac. I also want to say some Chrysler Corp. engines used hex drives.

It might have been in a ford Vannette from 1959 (way back memory I also had a Chevy Step Van (which I thought it was). Jim

 

[used red MN]

It might have been in a ford Vannette from 1959 (way back memory I also had a Chevy Step Van (which I thought it was). Jim

Jim, are you saying in your mind you confused the two? The Ford had the problem, but you confused it with the Chevy step van? If the Chevy van was from the 60’s or later and had a 250 or 292 six or a V8 I am sure it had a tang drive pump. The stove bolts 216, 235 & 261 are the ones I am not a 100 percent sure on, but somewhere near 85%.

 

[Janicholson]

Jim, are you saying in your mind you confused the two? The Ford had the problem, but you confused it with the Chevy step van? If the Chevy van was from the 60’s or later and had a 250 or 292 six or a V8 I am sure it had a tang drive pump. The stove bolts 216, 235 & 261 are the ones I am not a 100 percent sure on, but somewhere near 85%.

I am now saying I did confuse the two. I have just looked at chevy oil pumps and all seem to be slot driven. Just 40 plus years of reality going by. Jim

 

[Angle Iron]

Which GM used hex shafts? Trying to remember if maybe Olds or Pontiac? I just can't remember. Chevy used the slotted round shaft. Ford was hex.

Had a 73 Olds 98 455 ci that had the worn out hex drive.

 

[marloweg]

360 Fords in school buses were good fort that one good thing the distributor would stop turning and did not hurt anything