Hitchcocks Forum

At a recent oil change, I inspected the magnet in the oil filter. It was covered with iron filings! The history to this is that it was the first oil change since an engine rebuild, about four years, but less less than 1000 miles ago. During the rebuild, I replaced failed main bearings, big end, oil pump worm and spindle. I can't actually remember inspecting the magnet at that time; if I didn't, then the failure of the main bearings would probably account for the iron filings. If the filings have accumulated since then, something is up! What do you think is the most likely source? I'm worried about the oil pump spindle.
'89 350 Bullet.

Well, if you can't remember if you checked it at rebuild I would clean it, put it back in and check it regularly.
It also doesn't take long to check the oil pump spindle.
If you are talking about fine dust then I wouldn't worry too much.

I would suspect that the residue of the previous failure has not been completely removed, it's amazing where it hides.

Don't worry too much at this stage, run the bike for a hundred or so miles and recheck the magnet and filter if all OK then check again at around 500 miles.

First oil change in four years but less than 1000 miles?,after a full rebuild?, blooming heck (or similar) no wonder the bike is protesting, you naughty boy.

With an average mileage of well below 1 mile a day I'd not be over-anxious!

Hi John, I would check the crankcase scavenge strainer plug gauze - the hex plug under the engine nearest the front. If that is clean, don't worry. If there is debris on it, it might be left overs from before if the cases weren't cleaned out too well, but if you know you did a good job of cleaning before reassembly and there is dirt here, I would keep an eye on things at the very least, anything wearing or failing in the engine apart from the timing gears, cams etc will leave deposits here. !000 miles and 4 years for the oil is not asking for trouble, but an oil change wouldn't hurt, I suppose. Regards, Paul.

Thanks all. Hard to see how much could have remained in the engine after a rebuild, and I can't imagine that I didn't check the magnet at the time. How easy is it to check the spindle? Do you need to take the right side cover off?

Yes John, remove timing cover (careful, quite a lot of oil in there) and you can inspect the oil pump drive. You can also check that the oil pump spindle rotates. It should go round with thumb pressure. You'll likely need a new gasket on reassembly but don't get a cheap one from Ebay. Some of them are too thin and the case binds up on the shafts.
There's a tech note here on the subject.

Oh, and don't lose the (very thin) shims on the camshafts. They can stick to the case as you pull it off and go walkabout.