These are the spring pins from grainger
Unrestricted .080 hole pushrod
Restricted pushrod
Pins
Start and hold spring pin with Hemostats while tapping with the hammer
Tap with hemostats holding the pins until you can’t go farther with the hemostats on
Tap the pin in until flush with the end surface of pushrod...........
......Like this
Clean with tip cleaner rod, spray out with brake parts cleaner, blow out with air, spray with oil to keep rust away
We have some nice, heavy duty pushrods that are the correct length, but they have .080 oiling holes top and bottom.... and we need restricted pushrods to keep the oil down more in the mains and lifters, and not up in the heads.... the goal was to get .035 to .040 oiling holes






ideas researched and decided against:
1. Pipe cleaners- yes, they work, but they will dump a bunch of fuzz through the oiling system and the wire will eventually come out and get broke off by the rocker arm and leave tiny metal wire pieces circulating in the oil.

2. Roll pins- local hardware store had some that fit mediocre to crappy at best, not very thick roll pins and restricted hole size was still .055 diameter, and roll pins weren’t tight enough to trust. Sizes were either too small or too big to be tight.

3. Have new ends installed in pushrods- could split or damage the pushrod when disassembling, would likely change the overall length, which is correct.

4. Buy new restricted pushrods for $200+




my solution:

spring pins!

More specifically, 2mm diameter by 8mm length spring pins from Grainger.

These are much stronger than roll pins and they have a much higher tension as well with high quality steel. The other added benefit is they have the proper size hole when they are tapped into an .080 pushrod hole.

Once the spring pin restrictor is installed, it has a hole size of .0375-.038, according to pin gauges, so it is virtually a perfect restricted pushrod, which normally come with .040 holes.

I did not use loctite, as these were a very tight fit with decently aggressive taps from the hammer to slowly fit them in.


Please use at your discretion and skill level, ymmv, and I am not responsible if you mess up anything with this mod.

Pretty cool, I don't know so I ask does the restrict or go at the bottom of the rod or the top or does it matter ?

I just put them in the bottom near the lifters, but I don’t see how it would really matter if they were installed on the top/rocker side instead.