My series 2 e-type engine (#7R8818-9) has the ‘scalloped’ camshaft sprockets Dick Maury recommends be replaced in his Georgiajag.com article. Given I am currently in the process of rebuilding it, it seems like a good time to replace them. I have received new sprockets with pins that must be installed. The end of the pin has a cupped end that apparently must be peened into place. So far I have not been able to get the pin to sit fully perpendicular to the sprocket. Any tricks or suggestions?
You are talking about the central pin protruding out of the center of the serrated plate? It is there for convenience…to help with positioning the plate during assembly and also head R and R. It is not strictly needed so long as the front end of cam has the oil gallery plug in place.
On early engines, the pin served to plug an oil passage hole, but your engine shouldn’t have that issue.
Lee140FHC,
Yes, it is the central pin that attaches to the serrated plate. I had hoped the sprocket would come with the pin already attached in place. I agree that the pin is not necessary but being a bit ocd I want to get the pin installed properly so it won’t wobble when the cams are turning.
They are sometimes a little loose on production engines, so by no means perfect but you can certainly peen them in so they sit about straight within a few drgrees so they don’t touch the carrier…
I have figured a way to make the pin fit almost straight. (the original cam sprocket is not perfect either).
I fashioned a jig made of two 9" lengths of 1 1/4" angle iron. I placed these over a piece of roughly 1" square wood stock. I then drilled two holes near the each ends of the 9" angle irons. Both go through one angle iron, the wood stock and the other angle iron. I then put two 5/16" bolts through these and tightened nuts on them to keep everything sandwiched together. (The jig looks like a square piece of wood completely wrapped in angle iron)
In the middle, using my drill press to ensure all was squared up, I drilled one 5/16" hole (the size of the camshaft pin) through one side of the angle iron and the wood stock but not through the lower angle iron.The depth of the hole from the top of the angle iron to the surface of the lower angle iron is 1 1/4"- the same length as the sprocket pin.
With the jig held firmly in place in my bench vice I tapped the pin into the hole. The pin bottoms out on the other lower angle iron. The cam sprocket fits right on top of it. the jig ensures that the pin is perpendicular to the sprocket with the sprocket laid flat on the angle iron. With the pin now bottomed out against the lower angle iron, I could heat the pin and peen it in place.
I want to double check views expressed in these April posts and my questions are:
Is this sprocket pin installed “only for convenience” and not necessary in operation?
why don’t maintenance manual asy anything about peening out the end of the pin to keep it in place?
If not held in tight, isn’t there a risk the pin will come out when engine running and fall into the chain and sprocket gears and causing a tragedy?
And what was Lee140 talking about when he wrote
“As long as the front end of can has the oil gallery plug in place”? Was this for the 3.8L engine or something other than my 4.2L?
Early engines allowed pressurized oil to flow out of the camshaft center and then on out to the cam chains. This chain-oiling scheme was abandoned but the oil gallery in the cam remained, of course. The 4.2L cams I’ve seen have a plug in the end of that gallery…but even that plug would not be needed IF the serrated plate did have the pin installed, which would also serve to stem any flow of oil. The early pins were retained by a circlip, later pins either peened or welded(I suppose), I’ve never seen one threaded…too risky.
John/jagman
I have tried peening with my version of a jig but not successful enough to hold the pin in tight and vertical
Then I noticed in your early post that you heat the pin before peening. Can you tell me if this requires an acetylene torch or is a propane torch not enough?
Phillip, I used an oxy/acetylene torch. This is not to say a bigger hamer and a propane torch might t do the job. The key for me was the jig I described in an earlier post. It allowed me to keep the post and the cam gear at 90 degrees when I peened the head of the shaft.