Listed an earlier post called "it didn't help...what now?) regarding lifter noise I coudn't get rid of. Today I bit the bullet and removed the cam and lifters. When I removed the timing cover I noticed that the pointer on the cam sprocket was at the 1:00 o'clock position with number one cylinder at TDC, the balancer lined up with the timing tab and the rotor pointed at no.1 terminal on the cap. I have no idea how this happened as the engine ran fine except for the lifter noise. (I assembled the motor) As for the lifter noise I may be on to a clue as I noticed the front cam bearing oil holes were at 4 and 8 o'clock. The oil passage runs above the cam and I believe, but am not sure that the oil passage at 12 o'clock oils the cam bearing. I looked at a junk 307 block I have and the oil holes in the front cam bearing were at 12 and 4 o'clock and I was able to feeed a wire into the 12 o'clock hole to confirm that it was lined up with the oil galley. If these holes are not lined up would it cause the engine to not produce enough oil flow the the lifters to keep them pumped up and run quiet? I'm going to replace the cam and lifters with name brand products as the ones I took out I believe were generic. By the way I was able to get the pushrods to oil the rockers but it seemed like it took a long time during prelube with my distributor lube tool as well as after I would start the engine. Could this also be a result of the oil hole being mis-aligned? I'm almost more concerned with the oil problem than the cam sproket being off however I must say it intriques me as to how it could have gotten like that.
What do you guys think???


John

John,

To answer the question about your oil holes in the cam bearing, there in a groove in the block under the cam bearings so it don't matter where the holes are orented they get oil. The front one is the only one with two holes, all the others have one hole.

I know you were asked all the questions on your other post, but being you have it torn down are the plugs still in the front of the block?

When I eat I'll explain the timing mark.

Larry

Larry, Thanks for the reply. The oil plugs are in and staked. I'm not convinced about the groove in the block around the outside of the cam bearing. On the 307 block I can definitely get a probe wire into the oil galley. On my 350 I see and feel metal through the oil holes. If I can fugure a way to get the bearing out without trashing it I may try just to confirm if there is a groove or not. Also the oil holes in the rest of the cam bearings are lined up properly.

John

John,

Being you have the junk 307 knock the front cam bearing out of it and you will see the groove. You will most likely ruin the cam bearing in your good engine, even if you have a cam bearing knocker the bearing will go inside and you will have to pull the pan to get it out.

I have a few more minutes before I have to get off until later tonight, so I'll post this and if you want me to explain some more about the timing marks post back soon and I'll let you know.

Larry

John,

Being you have the junk 307 knock the front cam bearing out of it and you will see the groove. You will most likely ruin the cam bearing in your good engine, even if you have a cam bearing knocker the bearing will go inside and you will have to pull the pan to get it out.

I have a few more minutes before I have to get off until later tonight, so I'll post this and if you want me to explain some more about the timing marks post back soon and I'll let you know.

Larry

John,

If the cam bearing is in just the right place you can get a wire through. The early 283's you had to line up the holes, but then GM Larry/ John proofed it with a groove.

How ever when I am installing cam bearings I still line them up so I can see the hole through the main bearing hole. That is hard on the front because of the angle of the hole and I try to split the difference on the two holes, in the front bearing.

Here is a little more,
Larry

Larry, Your right about the groove. I guess I was anxious and hoping I had stumbled onto my problem. I'm still going to replace the cam and lifters. Have been checking the cam lobes with a Starret dial caliper and have been getting some strange readings. No two lobes measure the same. I know a caliper is not as accurate as a micrometer but I'm getting readings from .312 to .417 and everywhere in between (doesn't matter if it's an intake or exhaust lobe). The cam has only been run in the car for less than an hour and the lobes show no wear. The cam and lifters were part of a shortblock kit I purchased from a "reputable shop" ?? and the cam came without a spec card. For all I know it's a reground. I'm usually fairly particular about these things but the car is going to be a highschool heap for the kid. Regarding the cam gear I just can't figure out how I could have installed it with the index marks lined up and have it come out with the cam sprocket index at 1 o'clock with no. 1 at TDC on the compression stroke.


John

John,

As far as the timing marks, the dots on the crank and cam gears must be lined up as you said for proper cam timing; however that is not TDC#1, it is TDC #6. After lining the marks up at 6 o'clock/12'oclock rotate the engine one more full revolution; this will be TDC #1. Both will be straight up.

If your cam gear mark is at 1 o'clock with the mark at TDC on the balancer/pointer, I would double check for true TDC#1. It sounds like the balancer is marked incorrectly, the pointer is off, or the outer ring of the balancer has slipped. You need to do this to get the correct amount of timing in the engine. Unfortunately this doesn't affect your noisy lifters.


Good luck!
Jody

John,

I do so many post I get lost sometimes, so is this the block with the resticters in it, and if so can you pull the tranny and get to them? If it is the one, I don't think the hyd lifters will work with restrictors. I'll check back after church.

Larry

Jody, your right, I'm brain dead over this lifter thing. The cam and timing marks on the balancer are all ok.

Larry, Mine is not the block with the restrictors. I read that post too. No oil leak out the back so I know the rear ones are ok and I can see the front ones which are in and staked. I'm going to pull the oil pump and check the relief valve while I have the pan off. I welded the pickup on (it's in the correct location) and I removed the relief valve and spring prior to welding to keep them from the heat. Oil pressure at he guage at idle is 45lbs so the pump should be ok. If the oil filter is by-passing it shouldn't effect oil pressure just send oil around the filter so that shouldn't be a factor. Also pulled a rod and main cap and the bearings look good. Can't help but think I got a nasty set of lifters and a bum cam.
When I fix this, and I will!!! It'll be one more to chalk up to experience.

John

Hey John,

Since you have the pan off and I think your block was vated, some machine shops knock out all the plugs in the block and assume we check all this before assy. There is a plug under the rear main cap that if left out will cause the oil to by pass the filter, but not affect the lifters. You seem knowledgble but when you talked about the oil by passing the filter I thought of this.

The passage is under the rear main cap where the main passage goes to the filter the small plugs like the ones in the front of the block go there, about 1 to 1 1/2 inches up in the block. Just a thought while you have the pan off.

I bet you did get a bum set of lifters though, hope something said here helps. And by the way I like your I'LL FIX IT attitude, keep on trucking.
Be a good Bull Dog.

Larry

Larry, Pulled the rear main. The galley plug is in place as it should be, just above the oil passage that goes from the oil filter to the rear main. Pulled off the oil filter and when I turned it over to drain it it was less than half full. I haven't pulled the relief valve yet but the fiber disc was seated properly and I could easily move it off it's seat with a screw driver. Not sure whats going on with that. Rear main bearing and a rod cap I pulled looked good for wear and oiling. Any thoughts? It's getting late so I'll pull the releif valve tomorrow.

John

Hey John,

You don't suppose that the lifters were anti-pump up lifters do you? You have probably looked at the oil pump by pass by now but I don't know of any thing else besides leaks in the oil gallies, or oil pressure that can cause your problem, and all this we have already discussed.

I am like you in that there has to be a reason for this and I want to find it this time in,and fix it and be done.

At this point I don't know what else to do but put it back together (new cam & lifters) and see what happens. If I have a brain storm in the night I'll get up and post it.

Larry

Larry, The new cam and lifters will be here tomorrow. (Crane) If the lifters were anti-pump up that might explain the noise but I'm kinda thinking that the low oil level in the filter might be a "BIG" air pocked that just wouldnt bleed out. Even though I filled the filter with oil before initial start-up. Because everything seems to check out I am planning on installing the new cam and lifters and fire that baby up again. Should have it going by Sunday. I'll be sure to let you know what happens. Cross you fingers.

John