345 cam braking timing gear teeth.

3

385 series ford

New member
I have bough a 73 pick up. It has a 345 in it. It also had some issues. The first one was front bushing missing. When you stepped on the brakes. The direction would veer off. That was an easy fix. Latter I found a second issue. The timing gears would break there teeth off. I also noticed that just before that would happen the oil pressure would dump off to no oil pressure. Latter I figured the cam was walking out and in till the timing gears would break. From my experiences most cams have a thrush baring or washer. But I've seen nothing on the front of the block or on the front of the timing gears like a button. Is there one on the back of the block? If so then I'll have to pull the valve train apart up to the rockers to get to it. That's what I see myself having to do. Please give me some info on my 73 with 345 pick up.
 
The primary weak point within the IH sv8 engine family is cam bearing failure. When the bearings delaminate and lose their babbit layer, it isn't very long before the entire bearing disintegrates into chunks which fall down into the pan. When a cam bearing or bearings fail inside these engines, top end oil supply is adversely affected resulting in persistent valve train and lifter clatter along with a corresponding low and erratic oil pressure readout as viewed on a wet oil pressure gauge. If an engine is run long enough in this condition, catastrophic damage to the timing gears is inevitable. I suspect that if you were to remove your oil pan, you would find a small handful of cam bearing kibble residing in the bottom. Your engine would benefit greatly from a complete overhaul.
 
Thanks for the reply. But that doesn't quite explain the gear breakage. Plus I left out one tidbit of info. I did mention that the cam May have been moving in and out. As one would if it didn't have a trust washer or bearing. But I didn't say, once I had the timing cover off. I found the cam had walked out to the point that the gears weren't meshing up like they should all the time. They had come apart so much, that the distributor wouldn't turn. But I could turn the cam by hand after I had the cover off. It had walked that far out of place. And I had no lifter noise at anytime. The only metal I found in the pan was timing gear. No babbit. And it had good oil pressure all the time. Right up until the gears would break. What gets me is I could push the cam back to it's full backward location. And at no time had the lifters unseated the cam lobes. There has to be a shim, button or bearing that keeps the cam in a fixed location.
 
There is a retainer/ thrust plate right behind the cam gear. It is heaps in place by two large philips flathead screws. It's easy to see through the openings in the cam gear. If you have the cover off it should be staring you in the face. Could you post a photo of what you are describing?
 
That's what it sound's like Robert, the front cam plate is loose or the screw's/bolt's sheared off,letting the cam walk out. Jeff:eek6:
 
Yes it did stop running, and put me a foot. About a hundred of miles from home. I lived in kannapolis nc and I was working in senica sc. I was on i85 near the weigh station when it happened last. And that was back in the 80's. I don't have pictures to offer due to the truck setting in a pasture and nearly covered in briers. I want to get it going again so I can sell it. I was run over by a ford300 with a tiller behind it. When I can get around better I will fix it up. So I can pay my mounting bills. And to any questions on selling it now, that answer will be no. I need as much money from it as I can get. To sell it now would mean I would get that much. I will be putting on a 4 barrel intake. One I ran across some time back.
 
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