Something else I never thought about....

This oil pump showed up in the mail yesterday. I was supposed to install a new gear and bushing in it but as soon as I took it out of the box I saw this scoring in the main bearing housing. It appears the engine had spun the main bearing and wallowed the housing out substantially. The other thing I noticed is there is no part number stamped on the housing. I don't normally pay any attention to that but I thought the housings all had the Ford part number stamped on them. The only pumps I had handy to look at are all the later ones with 3/4" gears and they all had part numbers on them. This one is the earlier version with 9/16 inch gears. The absence of a part number led me to suspect the cap was an aftermarket replacement. I asked the guy that sent it to me but he said he just bought the tractor and has no idea what may have been done to it. So just to satisfy my curiosity has anyone ever seen a factory front main cap that did not have the part number on it?

TOH

Later pumps have a strong part number that may have been cast in. Early pumps had stamped numbers, some stamped lightly, but I don't remember seeing an original that didn't have a number.

(quoted from post at 18:20:11 11/16/16) Later pumps have a strong part number that may have been cast in. Early pumps had stamped numbers, some stamped lightly, but I don't remember seeing an original that didn't have a number.

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It's not something I ever took note of until this one showed up. The later pumps I have laying here all have 8N-6603 solidly cast into the housing. I could not find any indication of any number stamped or otherwise on the one in the picture. My gut feelng is it was an aftermarket replacement housing - and as another sharp eyed observer pointed out offline it looks like the bearing may have been installed with the oil passage blocked off....

TOH

(quoted from post at 23:38:16 11/16/16)

(quoted from post at 18:20:11 11/16/16) Later pumps have a strong part number that may have been cast in. Early pumps had stamped numbers, some stamped lightly, but I don't remember seeing an original that didn't have a number.

Click to expand...

It's not something I ever took note of until this one showed up. The later pumps I have laying here all have 8N-6603 solidly cast into the housing. I could not find any indication of any number stamped or otherwise on the one in the picture. My gut feelng is it was an aftermarket replacement housing - and as another sharp eyed observer pointed out offline it looks like the bearing may have been installed with the oil passage blocked off...

TOH

Click to expand...

The bearing shell insert halves are both the same, both have the oil hole even though it's not needed in the lower half. That prevents people from mixing them up and blocking the upper oil passage.

(quoted from post at 11:20:19 11/17/16)

(quoted from post at 23:38:16 11/16/16)

(quoted from post at 18:20:11 11/16/16) Later pumps have a strong part number that may have been cast in. Early pumps had stamped numbers, some stamped lightly, but I don't remember seeing an original that didn't have a number.

Click to expand...

It's not something I ever took note of until this one showed up. The later pumps I have laying here all have 8N-6603 solidly cast into the housing. I could not find any indication of any number stamped or otherwise on the one in the picture. My gut feelng is it was an aftermarket replacement housing - and as another sharp eyed observer pointed out offline it looks like the bearing may have been installed with the oil passage blocked off...

TOH

Click to expand...

The bearing shell insert halves are both the same, both have the oil hole even though it's not needed in the lower half. That prevents people from mixing them up and blocking the upper oil passage.

Click to expand...

I thought that might be the case and it eliminates one possible reason for the spun bearing. Now I am back to wondering if this is an aftermarket cap and an example of what you risk if you fail to have it properly fit to the block...

TOH