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Hello, I'm looking for some install tips for the camshaft gear on a 261. The first time it didn't go so well. Heated the gear up to around 250 F, tried to slide it on but was too tight still. Pressed it the rest of the way and damaged the aluminum hub on the gear. camshaft and gear were free of debris and burrs. I bought a new gear and am going to try it again. Anyone have any tips? Would I be able to get away with heating it to 300 or 350 F? If it were steel I'd have no problem with it, just new to working with aluminum.

Thanks

350 degrees won't hurt the gear. You might also try putting the cam in the freezer for a while, or soaking the drive end in a bath of dry ice and alcohol. That gets the temperature of the cam down to 50 below zero or so. The hot gear should practically drop on after that, or seat itself with a couple of smacks with a big dead blow mallet. Don't forget to sandwich the thrust plate between the gear and the cam- - - -I've done that occasionally, or forgot to put a nut on a piece of tubing before making a nice-looking flare and having to cut it off and try again!
Jerry

Also don't forget to put a feeler blade of the proper dimension between the gear and the thrust plate to get the proper end play. I remember 0.010" but you better check.

Just did this a few days ago. I pressed the old gear off the cam, bored a hole in a piece of 1/4" plate and slotted it so it was "U" shaped. I slid this onto the cam right between the first lobe and front bearing journal. Sat the plate back in the press and hung the cam from it. I put two .003 shims (manual says .001 to .005 clearance) between the journal and the thrust plate and heated the aluminum gear in a toaster oven set at 250 F. Popped the heated gear on the crank, placed a short piece of pipe on the gear hub (but larger than the cam snout), and pressed the gear on. I had to fiddle with it a bit as it pinched the shims and I couldn't get them out; a bit of wiggling and pressing the gear back a bit got it done. I think you're gonna need a press to do it with any finesse at all and guarantee the correct clearance for the thrust plate.

Good to know, I thought it was just supposed to press up tight against the thicker inner ring and that gave the proper clearance between the thrust plate and cam gear.

The 235 timing gear has a shoulder that sets the end play correctly without any extra spacing being done. When we assembled John's 261 with a new timing gear set about a year ago, I checked that dimension with a depth micrometer, so I'm not just guessing. The 194/230/250 engines require that feeler gauge procedure, I believe. Also, although the cam thrust plate for the 250 looks like one for a 235/261, it's a different thickness. Don't try to swap those parts.
Jerry