Broken camshaft?

[windtrader]

Just curious why more owners do not stockpile or take a bet on a running salvaged motor. They are not cheap but seem a reasonable option to do an easy swap and back going in no time. Take your time sorting out the old one, maybe scrounge around for parts to rebuild for future use or sell off.

[lovetofix]

I'll second Leid Diesel, they have engines and parts a plenty. Even have 71 series Jake exhaust bridges.

You could do this to your engine just to be sure it's good to go.

[Iceni John]

I thought it was the cam or gear train on the rear, it's not a big job once you get the head off I pull the cam from the front so I don't need to pull the engine to remove the bell housing

I spoke with the lead mechanic at the place I may use to fix it (they specialize in 2-stroke Detroits and buses, especially Crowns), and he said they'll have to pull the engine to separate the drive gear from the camshaft.   How do you do remove the cam from the front without pulling the engine?   He also said the idler/reversing gear may be the culprit.   I took the valve cover off today and saw that the camshaft is intact along its length (both the rear and front cylinders' rockers move when I turn the pulley), so it's either broken at the drive end or the gears are broken.   What would cause this to happen?   Boomer says that in 53 years he's had only one camshaft failure, and it's evidently not a common failure.

Another problem is that some or all the valves on that side may have hit the pistons, so they're probably bent.   I was going to check the other camshaft, but there's no point now:  I'm in for some serious work one way or another.   Plus, I'll have to spend a lot just to get the bus towed 55 miles to the repair place for them to give me an estimate.

Thanks, John

[chessie4905]

If that was my engine, I'd  pull it out and tear it down. Camshaft not turning is going to allow valves to hit pistons. Plus maybe something got in gear train. This is not going to be a quick fix.

[luvrbus]

If it is the idler gear the engine doses have to come out,the idler gear has a bearing that goes bad.The cam will come out from the front. Yvan probably made a Utube video of it,I learn the trick many years to keep from removing the old Funk gear box with 4- 2 stage pumps mounted to it (that is the correct name Funk),machine work on the heads when a gear train goes is going to cost nowadays $2500 ea now for a 8v92 done right.the 8v92 would break the cam with the 50D a lot before DD upgrade a cam just for the 50D