Hydraulic lifter / cam lobe issue

[coldair]

I failed to tell you my buddy's truck ran for 2 years with the cam bearings gone. Just don't run it at high rpm alot I think that's what made the cam break. ( 4000 rpm through mud holes)

 

[jasonmark1993]

Looks like a cam bearing to me...or half of one anyways.

 

[jeffgtoman]

While the cam was out, did you look inside the block to see if there was a cam bearing missing? If so, that would explain the cam lobe failures. The missing cam bushing will cause a drop in oil delivery to everything above it. Do you have oil coming out the top of all of the push rods? I'm not even sure this thing would carry much oil pressure at all with a cam bearing missing. Better start getting the next engine ready.

 

[jeffgtoman]

Actually, a missing cam bearing will also starve the crankshaft for oil too. Oil is going to travel the path of least resistance so you will dump most of what the oil pump produces out this cam bearing hole and there won't be any pressure left to force oil into the rod bearings. Do you have an oil pressure gauge hooked up to this engine?

 

[jeepboy45]

While the cam was out, did you look inside the block to see if there was a cam bearing missing? If so, that would explain the cam lobe failures. The missing cam bushing will cause a drop in oil delivery to everything above it. Do you have oil coming out the top of all of the push rods? I'm not even sure this thing would carry much oil pressure at all with a cam bearing missing. Better start getting the next engine ready.

No, I wish I did look... Normally I would have just for curiousities sake, but I just didnt. It wasnt till the next day that we dropped the oil pan.. By then, we had already put on the gears and chain, timing case cover, water pump, alt, PS pump the previous day.... Wish I had looked. I kept thinking that maybe the bearing had been in the pan all along. But yesterday I was looking through pics of pulling that engine, and there were a couple of the pan off the engine. It wasnt till then I realized that I had pulled the pan when I got it, and now know it wasnt in there before.

Actually, a missing cam bearing will also starve the crankshaft for oil too. Oil is going to travel the path of least resistance so you will dump most of what the oil pump produces out this cam bearing hole and there won't be any pressure left to force oil into the rod bearings. Do you have an oil pressure gauge hooked up to this engine?

Yes, I have a mechanical autometer guage on it... My Jeep has sat in the garage for about a year with tranny probs.. But before that, it had REALLY LOW oil pressure, even by Jeep standards!! Towards the end of driving it, it would be good at startup - 7 or 8 minutes with about 40+ lbs... However, it would quicklly drop to about 8 and then to about 2 at idle.. It sits around 6 or so while driving around 30 mph... I know, not good..

I do know this... When I pulled the engine from a waggy a few years ago, I dropped the pan just to look. There was NO bearing in the pan then. As I mentioned above, the jeep had tranny probs over a year ago. That night I had to rev the out of it for the tranny to slowly SLIDE into gear... I wonder if I spun it then???? Only drove it another 5 miles that night trying to get home. It sat ever since, until I got the tranny rebuilt a few months ago, and started driving it again recently.... Maybe the damage was done that night over a year ago.. I dont remember ANY issues with the engine leading up to that night the tranny took a dive...

Is there any way of replacing a cam bearing, aside from taking the block to a machine shop?

 

[CJim7]

I would not run an engine with a missing bearing. Nope. No way, no how. That's just a one-way ticket to a grenaded engine.

There is a special tool that is involved in punching in new cam bearings. But Im still not 100% sure that is a cam bearing...have you pulled the main and rod bearing caps?

It is almost impossible to spin a cam bearing. The only way it is coming out of there is if it was knocked loose during cam removal...and that's not really an easy thing to accomplish either. If it is indeed a cam bearing, you will oil starve the cam trying to run it without repairing it....

 

[coldair]

I myself would never run a motor with any kind of noise that is isnt normal. I was just tell you what ive seen friends do in tight spots when cash was hard to come by.

 

[jeepboy45]

I myself would never run a motor with any kind of noise that is isnt normal. I was just tell you what ive seen friends do in tight spots when cash was hard to come by.

Money is super tight right now. My Jeep is not my daily driver. In fact, since late 1999 when I finished my full body-off project, it has just over 30K miles on it.

That is why I am hoping it will last me through the summer and into early fall. Trying to slowly come up with funds to build a strong 360 in the meantime.

I appreciate everyones imput.