Wrist Pin Retainer/Clip - Need Help!

[Matt Wilson]

I'm in the process of rebuilding a 251 and converting it to a 265 for installation into my Power Wagon.  A few weeks ago, I had one of the new Sealed Power pistons out of the box, and I dropped one of the wrist pin retainers/clips on the floor.  I have spent several hours looking very carefully and thoroughly through all the boxes under and around the workbench where I was standing (in fact that entire quadrant of the garage), as well as on the workbench, leaving no stone (or box or tool) unturned, and have come up empty-handed.  I guess it bounced somewhere or I accidently kicked it somewhere, and I have no earthly idea where.

 

I tried calling Summit, since they sell Sealed Power products, and tried calling Sealed Power's Customer Support and Tech Support people, and they were unable to help me, except Sealed Power did give me a p/n (LR62).  An online search using that p/n turned up nothing.  I also called the vendor who sold me the pistons to no avail.   I found some retainers that fit the Dodge flathead six description on ebay, and they look very similar, but the dimensions are not right. 

 

These retainers don't seem to be sold separately for this application and are now considered obsolete per Sealed Power.  I purchased these pistons nearly 5 years ago and Sealed Power is using something else in place of these retainers, although the Tech rep was unable to tell me what.  The rep at Summit seemed to think the pins are now a press-fit into the pistons, eliminating the need for retainers....As an aside, if that's true, then I don't particularly like that, as it seems like all the wear would be focused on the connecting rod bushing instead of being spread across the bushing and the piston (not sure if someone can confirm that the pins nowadays are press-fit in the pistons).

 

Getting to the meat of my post, I wonder if anyone has a spare retainer - preferably new - from one of these Sealed Power pistons, that you'd be willing to share?  Below are photos showing the dimensions I took off one of the other retainers.  The first photo shows a dimension of 0.995", the second shows about 0.826" and the third shows the thickness at 0.063".  They're made of round wire, so the cross-section is circular, not square or rectangular like some retainers I've seen.

 

I'd be willing to pay for the part and shipping.  Having said that, I'm not sure if that places this post in the category of a classified or not.  If so, I'll move it.

Edited January 1, 2022 by Matt Wilson

[Dodgeb4ya]

You might have to venture 20' in all directions to find it?

You might go to a engine machine shop and talk to them...

[kencombs]

You don't necessarily need to find them by application.  Measure your groove width and pin diameter.  There are a lot fo  .990 diameter pins  on Summit and others.  They may be a different configuration, like end shape etc, but that is immaterial.  As long as they are the right OD and fit the groove snugly they will be fine.   Many engines are assembled with non-stock rings as an improvement.

[Matt Wilson]

5 hours ago, Dodgeb4ya said:

You might have to venture 20' in all directions to find it?

You might go to a engine machine shop and talk to them...

I've checked about that far in all directions, which is a lot farther than I can imagine it would have gone, considering there are boxes and other objects in the way.  I was thinking the same thing about the machine shops, thanks.

[Matt Wilson]

4 hours ago, kencombs said:

You don't necessarily need to find them by application.  Measure your groove width and pin diameter.  There are a lot fo  .990 diameter pins  on Summit and others.  They may be a different configuration, like end shape etc, but that is immaterial.  As long as they are the right OD and fit the groove snugly they will be fine.   Many engines are assembled with non-stock rings as an improvement.

Thanks, Ken.  I did start looking based on pin size and haven't come up with anything yet, but I'll try looking based on retainer dimensions and groove dimensions, although it's hard to get to the groove to measure it.  If the groove comes exactly halfway up the thickness of the retainer, then the groove width would be 0.064", but I don't know if that's the case.  I might be able to tell by installing one of the retainers, though and coming up with some "creative measuring." 

 

The pin size is 0.8591 per Sealed Power.  My pins are actually 0.8593, so I tried that and a range of sizes around that.  Interestingly, I just now tried 0.859, and Summit Racing's website came up, with pistons saying their pins are press-fit and don't use retainers, just like the Summit rep told me earlier.  I guess that's the way Sealed Power is going these days.  I know a lot of vehicles use pins that are press-fit into the connecting rods, but it seems that these are pressed into the piston.  Maybe that's ok, but if I was buying new pistons, I'd prefer that they be floating pins, the way Chrysler originally produced them.  Seems like they might wear the bronze rod bushing faster otherwise.

Edited January 1, 2022 by Matt Wilson

[kencombs]

8 hours ago, Matt Wilson said:

Thanks, Ken.  I did start looking based on pin size and haven't come up with anything yet, but I'll try looking based on retainer dimensions and groove dimensions, although it's hard to get to the groove to measure it.  If the groove comes exactly halfway up the thickness of the retainer, then the groove width would be 0.064", but I don't know if that's the case.  I might be able to tell by installing one of the retainers, though and coming up with some "creative measuring." 

 

The pin size is 0.8591 per Sealed Power.  My pins are actually 0.8593, so I tried that and a range of sizes around that.  Interestingly, I just now tried 0.859, and Summit Racing's website came up, with pistons saying their pins are press-fit and don't use retainers, just like the Summit rep told me earlier.  I guess that's the way Sealed Power is going these days.  I know a lot of vehicles use pins that are press-fit into the connecting rods, but it seems that these are pressed into the piston.  Maybe that's ok, but if I was buying new pistons, I'd prefer that they be floating pins, the way Chrysler originally produced them.  Seems like they might wear the bronze rod bushing faster otherwise.

I like the Spiraloc because of the wide diameter  range,  IF they fit your grooves that would be a good choice IMO. I finally found the 'press fit' pistons on Summits site, and am confident that is a misprint.  I've never even heard of a piston with pins that are a press fit, in the piston.  Lots are pressed into the rod of course.  Parts reduction scheme by the factory. 

I looked at several 40's-50s Mopar pistons on their site.  they all show the same info.   I bought a set of 218 pistons last year and they were just like they've always been.  IMO, the listing is wrong and the folks you spoke to have no idea what the product actually is, just what is on the screen.