LCA pivot pin question

[TheBigDude]

This is a pic of my drivers side lca pivot pin as it goes into the k member (68 DART). There is about a quarter of an inch of the pivot pin showing - it's shiny. The nut is tight but not torqued and I can move the lca up and down easily. Does the pivot pin draw down when you torque the nut once the car is back on the ground? The shaft is tapered. I am rebuilding the entire front end. The pin and bushings are new PST stuff. The pic if the best I get. I have no idea why it's upside down.

 

[72bluNblu]

The pivot pin nuts get torqued to 100 ft/lbs, so, yes, it will draw in some it if isn't torqued.

Also, if you have polyurethane LCA bushings, the LCA can move around on the bushings until the strut rods are installed. The poly LCA bushings aren't pressed onto the pivots like the rubber ones are, so they can slide about. Seems a little worrisome, but keep in mind the stock rubber ones are only held in place by the bonding of the rubber to the sleeve, which basically amounts to nothing. So both bushing types still rely on the strut rod to keep the LCA from walking back and forth on the pivot/bushing.

So, if the pivot nut isn't torqued and the strut rods aren't installed, what you're seeing now isn't what it will look like when everything is installed and torqued to spec.

 

[TheBigDude]

Interestingly, I have figured two things out. Both of the new pins do not have enough threads cut on them to draw down tight. In fact, with the nut tightened down the big fat washer just flops around and I can move the lca in and out of the bushing. So, I doubled the washers and got the passenger side properly installed. But on the drivers side I believe the problem is that the pin is too big. It's 0.804 and the two old pins are 0.790 and 0.787. Both of the old pins slide right into the bushing. I'm sure they are worn. But I do not believe I can draw down the new pin by torquing the nut. I have hit the lca from the torsion bar side with a big soft hammer and the pin will not seat down into the bushing. On the passenger side it did. I'm afraid to even try torquing the pin into place because it will be a ***** to get apart if it doesn't torque down. I think I'm going to call PST tomorrow and see what they have to say. Here is a better pic of the gap.

 

[TheBigDude]

Here is a pic of an old pin seated in the bushing.

 

[autoxcuda]

Something might not be machined right. Start measuring the features of both new and old pins and compare. With a venier caliper that measure to the 0.01 or/and a micrometer.

 

[PST]

If there is anything that I can help you with, with our product please let me know.

Thanks
James