Oil pump gerotor question

[Hossamania]

Nice!

[Buglet]

    I think someone had the wrong measurements for the freezer and hair dryer to work. Glad it work out.

[kd]

    I think someone had the wrong measurements for the freezer and hair dryer to work. Glad it work out.

I do too but proof that it is worth trying things that are not bridge burning before resorting to things like machining that there is no return from if wrong. 

[Scotty]

    I think someone had the wrong measurements for the freezer and hair dryer to work. Glad it work out.

Well it's winter here in OZ and at a guess the pistons were cold and the wrist pins were warm from handling and just shows how metal expands.

[PoorUB]

    I think someone had the wrong measurements for the freezer and hair dryer to work. Glad it work out.

Ya think?!

I questioned the measurements earlier.

[Adam76]

    I think someone had the wrong measurements for the freezer and hair dryer to work. Glad it work out.

I do too but proof that it is worth trying things that are not bridge burning before resorting to things like machining that there is no return from if wrong.

Yeah, my measurements might have been off.... but the fact is that under normal ambient temperatures the wrist pins would not go into the bores of the pistons for love nor money. That's why I did the measurements in the first place.

I still question whether this is right, because once I got the wrist pins in and they started to thaw out, they then seized inside the piston bore. I would imagine that for optimum function this is not ideal and may cause excessive wear on the connecting rod bushing?? I'm just guessing here. But I would be happier if they rotated freely in the bore like the set of pistons I did on my last build. 

Is a seized wrist pin anything to be concerned about?

Thanks

[SP33DY]

Yeah, my measurements might have been off.... but the fact is that under normal ambient temperatures the wrist pins would not go into the bores of the pistons for love nor money. That's why I did the measurements in the first place.

I still question whether this is right, because once I got the wrist pins in and they started to thaw out, they then seized inside the piston bore. I would imagine that for optimum function this is not ideal and may cause excessive wear on the connecting rod bushing?? I'm just guessing here. But I would be happier if they rotated freely in the bore like the set of pistons I did on my last build. 

Is a seized wrist pin anything to be concerned about?

Thanks

You should be okay. Years ago the Sputhe big bore pistons were all shipped that way with instructions to what you did. He said that long as the wrist pin was free in the connecting rod, it was good. Once the engine fires the aluminum piston expands enough to make the wrist pin loose.

He did some other things that were a little different, like using a copper ring instead of a head gasket... R.I.P. Alan!

[Adam76]

Ok, thanks. 👍 good to know.

Thanks again for the helpful info guys, much appreciated. You're legends.
Cheers.

[Buglet]

  You should be ok. I the early days you had to heat up the Harley pistons to side the wrist pin in. I just think your measurements might of being off.

[Adam76]

  You should be ok. I the early days you had to heat up the Harley pistons to side the wrist pin in. I just think your measurements might of being off.

Yep  thanks 👍

[Adam76]

Got the pistons and the cylinders on.  All seems well.

[Scotty]

You didn't forget the two o-rings on the oil return dowels  part number 11273 I hope 
Also the cylinder base o-rings part number 11256 

[Adam76]

You didn't forget the two o-rings on the oil return dowels  part number 11273 I hope 
Also the cylinder base o-rings part number 11256 

Thanks Scotty, no thankfully I didn't forget the cylinder base o-rings or the 2 o-rings for the oil return dowels.

I had the full 95" Cometic top end gasket kit and once I'd actually figured out why I was a few o-rings short -- I didn't need any cylinder deck o-rings because I had the MLS head gaskets!     then I had it sorted. For a minute there I was scratching my head thinking I was going crazy... 😂😂

[Scotty]

Good stuff