can you read my bearings ?

[blazer2007]

I developed a tapping rattle type noise somewhere in my 350 . I did alot to try and isolate it but didn,t find anything. I,m going to rebuild it anyway but just want to know what the bearing wear is telling me. I got it rebuilt about 10,000 miles ago and now I see he must of polished crank etc and put std. bearings back in and not really did a proper job. Anyway here are a pic of rod bearings 7 and 8 and the rear oil pump bearing . Can see some copper coming thru the side of thrust bearing.

[Ziegelsteinfaust]

I am not up on bearings.

But how did the cam look? Were any of the lifters cupped slightly?

[blazer2007]

cam and lifters looked nice and new

[mattfranklin]

Sometimes new thrust bearings show copper like that.

That rear crank bearing shows more polish in the journal area than I'm used to seeing.

The rods don't look horrible compared to what I've seen.

My most recent motor had an odd rod-rattling sound. It was the same sound as a rod noise, but at more of the rate as a bunch of bad lifters.
Heavy viscosity oil helped until it warmed up.
It turned out the previous rebuilder used standard size rod bearings on a 0.010 under crank on all of the rod journals.

[blazer2007]

This noise developed over a year, did it twice and went away in 20 seconds ,was like carbon knock. Then one morning started the truck and choke got stuck and revved way up until I bleeped the throttle and noise never went away. I do have another thread on here detailing all I did to try and find the noise if you want to look, but I did and replaced everything that might cause the noise and used a stethiscope but nothing, good oil pressure. I,ve got it torn down so much now I might as well rebuild it my way this time. Was just curious on the bearings

[AussieinNC]

There are a huge number of variables in building an engine,,,,and everyone has their own way of doing things...

1/ Use a outside micrometer to determine the journal size of the crank journals. Write down the figure

Also check for journals out of round.(Take two sets of measurements on each journal 90 degrees apart)

2/ Torque the rod bolts to spec and using an internal micrometer, measure the journal ID and check for out of round there as well. Write down the figure.

3/ Subtract the crank journal dimension from the rod bearing measurement and you will have your bearing clearance.

This is the only way to determine excess bearing clearances.

4/ You can use plastigauge but it not as accurate...

The rod bearings look pounded out, too much clearance...

The thrust faces of the rear main look normal...the surface of the main looks like the mains need to be closed and honed...most small blocks need this as a part of a full build....

Is this coupled to a manual or auto trans?

Pop the bearing shells out of the rod and check the imprinted size on the back....

Sometimes you can use a plus 0.001 bearing shell to close up excess clearances.

Are there any 0.001 shells in the build?

What oil pump was in the engine?
Is the bypass valve in the pump stuck in bypass mode?

[blazer2007]

It,s a turbo 350 with a lock T. converter . The rod bearings say STD. The oil pump is new and has good pressure ,about 60 pds. on cold start up and stays good depending on the Temp outside . I,ll let you know on the bypass valve.

[cadillac_al]

The rod bearings don't look bad to me. I don't know about that rear main bearing, it could be ok. I would have plastigaged them by now to get an idea on the clearance.

[blazer2007]

Originally Posted by cadillac_al

The rod bearings don't look bad to me. I don't know about that rear main bearing, it could be ok. I would have plastigaged them by now to get an idea on the clearance.

I going to take the motor out, is almost there anyway. I tired of doing this on my back. Just wanted a opinion of the bearings that I did remove

[cadillac_al]

10-4 it sucks to do it on your back. I have seen worse bearings out of good running engines so I don't think yours are that out of the ordinary. Once you start measuring things you will know soon enough if you have a problem. good luck

[blazer2007]

I find if I do stuff on my back I get things backwards. I make this mistake when fabbing up exhaust or a bracket ,patch panel etc. When I put the 2 rod caps back on I had to think which was # 7 and the same for #8 cap. Look from the top #7 is on the right side,crawl underneath it,s on the left . Easy to make a mistake on something so easy and in a hurry. Might as well freshen up the engine and new paint and of couse might as well clean up and paint engine bay , etc. Should be done by spring LOL Who knows what I will find on the other bearings. Thanks for your input,as usual you guys help alot

[vince1]

I didn't read your other thread but did you try re-adjusting your valves? I went through and loosened mine off a lot with it running and sometimes on cold start up one or two might tick a bit.

[blazer2007]

Originally Posted by vince1

I didn't read your other thread but did you try re-adjusting your valves? I went through and loosened mine off a lot with it running and sometimes on cold start up one or two might tick a bit.

This was more than a tick but I ran the engine with covers off and everything was fine, couldn't hear it with a stethoscope either. The noise was the same all the time hot,cold.

[crazy longhorn]

Just a thought.....if the back side of the thrust main is worn enough, the crank can move forward & one of the counter weights will (kiss) the back side of the #4 main webbing. I have seen this , more often on a stick shift vehicle with miles, or a heavy clutch, or a ballooned converter. It does also sound like a rod knock Take a look at the thrust flanges on the crankshaft, & you might check the end play(thrust) on the crank with your used bearings? Let us know...Longhorn

[burnin oil]

The bearings look good to me but a little worn for milage. New oils arnt what they used to be. Maybe a switch is in order. Do some research and form a personal opinion. When you ran the motor with the valve covers off did it make a huge mess? Like shooting oil past the fenders? If not thy are probably piddle valve hydraulics and can be noisy from not enough oil up top to dampen the lifters clatter. This lifter type more or less dribbles oil at idle. Don't want you chasing your tail. Otherwise longhorn is spot on. As long as you see no witness marks or accelerated wear the motor is probably fine. You may also be experiencing wrist pin knock. It is getting more prevalent than it used to be. Alot like the old forged piston sound before the motor warmed up.

[blazer2007]

I,m almost ready to take engine out but hurt my back and of course when it feels better I start lifting things like these stupid heads. One thing I did notice was the side to side movement on the rod bearings and if I wiggled them side to side real fast it makes the noise I,m looking for but everything I,ve read says side to side play is normal. Oh well just waiting for help this weekend to help me take the hood off. I used to do it myself but not today.

[crazy longhorn]

Side clearance on the rods should be .0025 per side x 4 (.010 clearance per pair). factory usually comes in .08-.010, per pair....while you can live with a little more, if you have say .030, or more , you will probably hear some noise. I also agree with burnin oil....you could have a wrist pin issue Longhorn

[blazer2007]

Well I hope Longhorn is correct. I can,t fix something when I don,t what it is. I went from obvious and easiest to now, taking the engine out. I,ll let you know,might take a week or 2 . Have this stupid thing called a job.

[blazer2007]

Originally Posted by burnin oil

The bearings look good to me but a little worn for milage. New oils arnt what they used to be. Maybe a switch is in order. Do some research and form a personal opinion. When you ran the motor with the valve covers off did it make a huge mess? Like shooting oil past the fenders? If not thy are probably piddle valve hydraulics and can be noisy from not enough oil up top to dampen the lifters clatter. This lifter type more or less dribbles oil at idle. Don't want you chasing your tail. Otherwise longhorn is spot on. As long as you see no witness marks or accelerated wear the motor is probably fine. You may also be experiencing wrist pin knock. It is getting more prevalent than it used to be. Alot like the old forged piston sound before the motor warmed up.

I,ve alway use Lucas high zinc. Lifters did dribble but I,m sure I would have heard that with a stethoscope, never know thou.

[truckdude239]

for 10k miels those look really rough id use a different machince shop

[blazer2007]

Originally Posted by truckdude239

for 10k miels those look really rough id use a different machince shop

I,m going to get machine work done in a different town and put it together myself. Was a good deal at that time for them to do it, but when I saw the bearings were standard i knew he just polished crank and put stock bearings in. With that motor being stock and from my 75 vette it should have had a least some turning on the crank. Oh well we,ve all gotten burned at some time