Restoring Rusty

[Gregski]

so then it was time for some Deductive Reasoning

1. the noise was there before I rebuilt the Top End

2. after replacing the Cylinder Heads, Cam, Lifters, Push Rods, Timing Set, and Water Pump the noise was still there

3. there is no play in the #4 intake or exhaust valves so it can't be a collapsed lifter

so I think it's a worn con rod

[rich weyand]

Yeah, it's in the bottom-end.

Simplest, maybe cheapest, and most complete (i.e. not leaving other problems for later issues) is to get the 350/260 crate engine and transplant your top-end onto it. New pistons, rings, rods, bearings, 100% clean passages, all in one package. Drop the Vortec top end on it, swap the cam, and you're done.

$1500 and free shipping from either JEGS or Summit.

[Gregski]

Originally Posted by rich weyand

Yeah, it's in the bottom-end.

Simplest, maybe cheapest, and most complete (i.e. not leaving other problems for later issues) is to get the 350/260 crate engine and transplant your top-end onto it. New pistons, rings, rods, bearings, 100% clean passages, all in one package. Drop the Vortec top end on it, swap the cam, and you're done.

$1500 and free shipping from either JEGS or Summit.

I wouldn't want to go flat tapped style bottom end if I was to get a short block, I hate the two piece rear seal

[rich weyand]

Originally Posted by Gregski

I wouldn't want to go flat tapped style bottom end if I was to get a short block, I hate the two piece rear seal

For the first 100,000+ miles, it wouldn't matter.

[Gregski]

Originally Posted by rich weyand

For the first 100,000+ miles, it wouldn't matter.

dudes tell me going roller gives you 20 more horse power with a slide of your credit card! LOL plus you aint gotta play the Zinc oil additives game

[rich weyand]

Originally Posted by Gregski

dudes tell me going roller gives you 20 more horse power with a slide of your credit card! LOL plus you aint gotta play the Zinc oil additives game

Just trying to hold down the wear and tear on the credit card.

Zinc additive is $5 per oil change. Not a biggie.

On the connecting rod bearing, yeah, I would go a couple thousandths over.

[Gregski]

drop your pan and slowly back away

here we are looking at #4

checked all the con rods and they all shift a hair side to side uniformally 1 - 8

[Gregski]

and here's what the #4 connection rod bearing looks like

Note: it still has the divits on it so it has not spun, which is the best I can say for it

so question is do I buy a stock replacement or a .002 over? and yes I am only replacing one bearing (I never said I am going to be proud of this "repair")

[Gregski]

went ahead and bought just a standard size bearing, for like $4.00 bucks

man where will I get my bearings when Trump builds that wall (kidding folks, don't get all political on me, let's just make this truck great again!)

[Gregski]

you know the drill, time for a stare and compare

old bearing and new bearing

[mini rant] I don't know about you, but I struggle to view these things as bearings, to me a bearing has balls in it, you know what I'm saying, these there things are like shims to me, I just can't wrap my small mind around the concept thats all [/mini rant]

[rusty76]

That really sucks. I hope replacing the bearing helps. Seems I've never heard my old truck not tick somewhere. Lol. My toaster(daily) is just too quiet. But it does have AC.

[Gregski]

well, so I replaced the #4 con rod bearing, did that make the engine ticking noise go away?

NO

my goodness, what is up with Rusty? so I parked it on the street and started drinkin'

[Jake Wade]

Keep in mind the cam turns at half the speed as the crank so a piston or rod noise would be twice as fast as a valvetrain related noise.

[SkinnyG]

Did you Plastigage #4? That would have been a quick way to rule out or condemn the rod bearing.

I still maintain it's a piston problem; I'm with peabobble.

[Gregski]

Gentlemen, could it still be the exhaust header even if the noise goes away when I unplug the spark plug wire on #4?

I am tempted to pull the headers off (at least on that side) and bolt up my old manifolds and see what that does, but if you think its a waste of time knowing that there is no noise with #4 plug disconnected than let me know.

[79sierra]

Originally Posted by Gregski

Gentlemen, could it still be the exhaust header even if the noise goes away when I unplug the spark plug wire on #4?

I am tempted to pull the headers off (at least on that side) and bolt up my old manifolds and see what that does, but if you think its a waste of time knowing that there is no noise with #4 plug disconnected than let me know.

Sure, but hard to tell without hearing it. I wouldn't put the manifold back on, I would pull the header and check the gasket around #4. Double sure would be to remove the header and check it for any high or low spots with a straight edge and also check the head around that exhaust port. Hope it is not internal!

[SkinnyG]

You won't likely feel any up and down play - you need the piston out, and try to rock them.... um... like, rock the piston down while you rock the con rod up - kind of feeling if the wrist pin hole is elongated.

Assuming a piston skirt or ring isn't broken.

[SkinnyG]

Oh. Exhaust leak....... Interesting.

Can you give a listen with a stethoscope or long screwdriver, and see if the sound is coming from the BLOCK, or from the HEADER TUBE.

Sometimes header tubes make a ticking sound, just the speed of the gasses hitting the corner of the tube or something.

[Gregski]

Originally Posted by SkinnyG

Can you give a listen with a stethoscope or long screwdriver, and see if the sound is coming from the BLOCK, or from the HEADER TUBE.

I tried that with both a stethoscope and a long screw driver, and a rubber hose, and my buddies tried it and none of us can pin point where the sound is coming from. I even got under the truck and tried to listen to it from there, still can't tell.

The stethoscope and the long screw driver let us hear the internals of the engine but thats not the ticking sound, also there is no tapping sound from the distributor, no sound from the fuel pump, no sound from the starter, no sound from the exhaust manifold, its so bizarre

actually drove the truck with #4 spark plug unplugged to show my buddy and man the truck sounds so smooth without it, I just wish I had a V8 and not a V7, lol

[Gregski]

well seems like this dude on YouTube has the same problem, and of course the video is abandoned and we don't know what it was or how he fixed it

Piston Slap, Spun Bearings, Valve Lash, Engine Noise Diagnostics

02 Engine Noise Diagnostics

[Gregski]

Man I wish I tested my pistons like this guy is doing in this video when I had my engine out and the cylinder heads out, check it out and tell me what you think

5.3 LM7 Piston Rock aka Piston Slap

[hatzie]

This isn't an LS motor or even a Vortec smallblock like you liberated the heads from. Tolerances were pretty loose on the earlier Gen I smallblocks.

Look in the 1974 service manual. The '70s GM engines were intended to be run on 10W40 and even 20W50 motor oil except at fairly low temperatures. The chart in the 1974 GM service manual says to run 5W30 if the outdoor temps range from less than -30°F to 60°F max. That same chart says to run 20W50 between 20°F to over 100°F.

Sacramento averages 60°F year round... For Sacramento to get below 20°F would mean the apocalypse is fast approaching.
Try swapping to a higher SAE weight oil... Running a good synthetic 20W50 should quiet her down and it will not hurt a thing to use year round. If it's a loose wrist pin it won't change a thing.

[Gregski]

Originally Posted by hatzie

This isn't an LS motor or even a Vortec smallblock like you liberated the heads from. Tolerances were pretty loose on the earlier Gen I smallblocks.

Look in the 1974 service manual. The '70s GM engines were intended to be run on 10W40 and even 20W50 motor oil except at fairly low temperatures. The chart in the 1974 GM service manual says to run 5W30 if the outdoor temps range from less than -30°F to 60°F max. That same chart says to run 20W50 between 20°F to over 100°F.

Sacramento averages 60°F year round... For Sacramento to get below 20°F would mean the apocalypse is fast approaching.
Try swapping to a higher SAE weight oil... Running a good synthetic 20W50 should quiet her down and it will not hurt a thing to use year round. If it's a loose wrist pin it won't change a thing.

ever since the engine rebuild I have been running 20W-50 engine oil with the Lucas zinc additive

yesterday we put brand new 20W-50 engine oil in with a brand new oil filter, the Lucas zinc additive and added the Lucas HEAVY DUTY oil stabilizer, our ratio is extreme for testing purposes of 2 quarts Lucas and 3 quarts oil, its really thick on purpose right now to see if it will quiet down the noise, and it does NOT

[Gregski]

Well, well, well, what do we have here?

Could that be numero quatro?

[Jake Wade]

You need some 1444 Felpro's