Bad cam bearings

[94 formula]

I'm pretty sure I have bad cam bearings in my car. What all am I going to need to replace? I know I have to pull the engine, timing cover, cam, intake, and lifters. Are my bottom end and bearings going to be ok or will they need replaced. Will I need to buy a new cam? Is their anything I'm missing?

[LOUD2000T/A]

cam bearings are a p.i.t.a there is a special tool you need because they have to be pressed in and out. i brought my 454 block to a machine shop and had him do it for me. didn't cost all that much. how many miles on the engine, because if you already have it out you may want to think about main and rod bearings also.

[Joe 1320]

Is their anything I'm missing?

The specialty tools required to do the job. A machine shop will need to do the cam bearings. IMHO, if the cam bearings are bad, so will the cam. They keep the cam exactly in line and spinning freely. Any wear and the cam no longer stays perfectly straight. Wear will occur.

[raroZ28]

time for a bigger bump stick

[WICKED LT1]

You may want to identify what caused them to fail. This is usually a lack of oil condition. Given that, what else may have been starved for oil as well. It is likely that some other damage occurred to the cam (Like Joe said) and maybe some things higher up the oil chain into the top end. HTH


-Paul

[Trash man]

since its out, just rebuild it if u have the funds and add the LT4 kit if u can

[fastTa]

You may want to identify what caused them to fail. This is usually a lack of oil condition. Given that, what else may have been starved for oil as well. It is likely that some other damage occurred to the cam (Like Joe said) and maybe some things higher up the oil chain into the top end. HTH


-Paul

For sure. Sounds indicative of poor oiling to the galley. Probably a sign of the pump going bad or a clogged pickup. I would definitely pull the pan and change the oil pump and while your there go ahead and tack the pickup onto the new pump just to make sure.

BTW what was your initial sign that the cam bearings were bad?

[DeWynter]

BTW what was your initial sign that the cam bearings were bad?

My question exactly, how do you know the cam bearings are bad?

[94 formula]

I think that the cam bearings are bad because when I start the car I get a horrible sound from the top end and it also sounds like there are loose marbles rolling around in my intake. I replaced my oil pump not long ago also.

[fastTa]

I think that the cam bearings are bad because when I start the car I get a horrible sound from the top end and it also sounds like there are loose marbles rolling around in my intake. I replaced my oil pump not long ago also.

Have you pulled the valve covers to inspect the upper valvetrain? Did you install the new oil pump yourself? How close to the bottom of the oil pan did you install the bottom of the pickup? Should be about 1/4".

Does the rotating assembly spin smoothly? Is your motor internally stock?

[94 formula]

Rotating assembly seems to spin fine. The motor is internally stock and the oil pickup tube was installed properly it was fine until now. I pulled the valve covers yesterday and everything looked fine. I ran the engine quickly with them off and no valves were sticking.

[fastTa]

Rotating assembly seems to spin fine. The motor is internally stock and the oil pickup tube was installed properly it was fine until now. I pulled the valve covers yesterday and everything looked fine. I ran the engine quickly with them off and no valves were sticking.

Well the first thing I would do is pull the drain plug and look for metal, maybe a puked lifter or two.

It is also not uncommon for the stub shaft to come apart. Brilliant idea that stub shaft.

If one or more of the cam bearings have indeed spun or puked, you are going to most likely have a difficult time removing the cam. If it were me I wouldn't bother putting a bigger cam in unless you plan on porting the heads. The main bearings should be OK. You can always just pull the middle 3 main caps and inspect the bearings and cranshaft journals. The middle 3 take the vast majority of the abuse from the crankshaft deflection, so generally speaking if they look good the #1 and #5 main bearings/journals should be OK.

[94 formula]

After I suspected the cam bearings were bad I took off the oil filter and cut it in half and looked for metal shavings of pieces of bearings and found nothing. I called a machince shop today to get a price estimate on replacing cam bearings and it was only around $60 if I do all the other work. He said I would have to bring him the bear block though no heads pistons and crank out. Is it possible to do this without removing all of this or does it absolutely have to be done. I'm not trying to skimp here I want to make it run right I'm just in college and have very shallow pockets as well as a limited amount of time.

Btw thanks for the help so far everyone I really appreciate it!

[fastTa]

After I suspected the cam bearings were bad I took off the oil filter and cut it in half and looked for metal shavings of pieces of bearings and found nothing. I called a machince shop today to get a price estimate on replacing cam bearings and it was only around $60 if I do all the other work. He said I would have to bring him the bear block though no heads pistons and crank out. Is it possible to do this without removing all of this or does it absolutely have to be done. I'm not trying to skimp here I want to make it run right I'm just in college and have very shallow pockets as well as a limited amount of time.

Btw thanks for the help so far everyone I really appreciate it!

Yes, cam bearings can be installed with the rotating assembly in place. This is called a blind install because with the rotating assembly in place, you will not be able to easily see whether or not the cam bearing oiling hole in the block lines up with the actual oil hole in the cam bearing itself. A mirror and a small tool such as a small allen wrench can be used to align the holes.

Of course it is easier to have the crank removed to do the cam bearings, but by no means neccessary. However, since you will have the shortblock out of the car most likely, I would go ahead and replace the rest of the bearings as well.