Does anybody know the correct size of the 3 mounting bolts which pass through the generator mounting bracket, and into the engine block?

Thanks!

5/16" - 18 UNC, 3/4" long.

I may also suggest that you have a few plain washers in addition to the split lock washers on hand. Install the bolts first, if they don't snug up flush to the mount pad on the block (and cleaning the holes doesn't help) then an extra washer will ensure that you get full clamping load on the bracket (#1 cause of failure).

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Mike!

Correct on the cause of failure, but 3/4" long won't bottom.

Thanks all for your assistance; removed alternator this morning, to get easy access to the 3 mounting holes for generator. Holes were filled with corrosion, grease, and who knows what else. PB Blaster did the trick, all clean now and ready for bolts.

I'm not sure if what I have in front of me is proper mounting setup for this generator. I'll describe what I see... on either side of mounting bracket is a circular rubber piece. A round metal cap is positioned on top of both rubber pieces. Finally, there is a metal sleeve which goes through all 4 of these pieces. The total thickness of all this (as seen in photo) is about 5/8" long.

This can't be correct, cause a 3/4" length bolt would not be long enough to get a grip in the block. Perhaps I should remove the metal sleeve, along with one of the rubber pieces and it's metal cap. Or just get a longer bolt.

Damian,

You've got the correct setup, and I was wrong -- you need longer bolts with that. I was thinking of the SWEM alternator bracket, which doesn't use the rubber mounts. Get bolts that will go into the block about 1/2" (they are 5/16 UNC -- I got that part right).