doesnt the whole engine have to be removed? any regular person cant even hear it, i just am pretty in tune with it. it sounds good still. so tell me more about swapping bearings. this is the first time i have ever looked inside the oil pan, i notices pistons are in pairs with 4 bolts. i figure the bearings are in there. i saw a metal flake up at the top of piston 1,2 right up against the front wall of the block. im sure this is something that is out of my realm, every mechanic is going to want to tear the whole thing apart. i need step by step help to get this bad boy on the road again!

 

Are you sure that you arent just seeing the piston rings?
There are rings around each piston to keep oil out of the combustion chambers and another set of rings to keep the combustion gases out of the crankcase.
Without the rings the whole thing just wont run.
As for replacing the rod bearings, easy as pie while still in the truck.
Just need a tourqe wrench, new rod cap bolts (if they are the stretch type), new bearings.
Done deal.
If you were in the Amazon you could use a Pepsi can as new bearings, I have seen it done on a Buick V6.

 

this was a little flake of metal like the ones in my oil pan. now i would like to describe the flakes. you couls actually see a small edge. the edge was grooved like its purpose was to seat in something. does this sound at all like a rod bearing part? and how do a turn the crank to get to the next bolts? spike, whats a good source for parts?

 

You turn the crank buy putting a big socket on the crank pully nut and then turning the engine over by hand, it will be easier to turn over if the spark plugs are removed.
And if you are going to be doing this UNHOOK THE BATTERY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
www.atlanticbritish.com
Most rod bearings are brass, is the metal brass?

 

Before you get into this farther, does the sound resemble a screw driver tapping the engine or a large hammer tapping the engine? The hammer type loww thud is more likely to be bottom half relater, and the light tick of a screw driver is top half. Sound can transmit through the block making it sound different from where it actually might be. Also, can you hear it from the top more than the bottom?

They make little nylon strips to check your bearings. Basically you put them in after you pull the caps and rotate the engine. The strip will flatten out and the line on them will be wider, the tighter it is. If you haven't done the bottom half of an engine before, I would suggest taking it to a shop. I got my front cover quoted, and to drop in new bearings was only $300 more

 

it looked and felt like thin aluminum, i could bend the shavings easily, the metal was soft. it did look brass colored in the oil! but im sure it was giving it a tint. i have been reading that if the bearing has been spun, that i need to machine the crank. there were very few shavings in the pan, no more than could fit on my finger tip. one decent size piece, like a piece of finger nail, the rest were literally flakes. hey spike , what is the torque spec for the bolts, and i dont know what stretch type bolts are.

 

Sounds like a piece of bearing to me...

Connecting rod nuts/bolts 50 Nm ..................... 37lbf.ft
Main bearing cap bolts +**
Initial torque - all bolts: 14 Nm ....................... 10lbf.ft
Final torque:
Numbers 1 to 4 main bearing cap bolts: 70 Nm ......... 52lbf.ft
Rear main bearing cap bolts: 90 Nm .................. 66lbf.ft

Download a copy of the RAVE manual. It is the workshop manual in pdf format. Google it, you can find it for free

 

Main bearing material is typically a lead/copper or tin/copper/antimony (babbitt) alloys but increasingly manufacturers are moving to aluminum. No brass. A fingertip worth of softer metal chips is usually the warning sign that the engine is "talking" to you and needs attention on the bottom end. If you want to be sure, pass a magnet over the chips and see what sticks. Crankshafts, rings, cams and lifters are all ferrous and will stick to the magnet. Pistons and main bearing material are non-ferrous and will not.

While we're on the subject, I know lots of folks here like the idea of a good old fashioned ATF flush or other internal engine cleaning process, but the thought of it gives me the chills. Main bearings fail when dirt or other abrasive beasties get caught between the crank journal and the bearing. I can't think of any faster way to stir up debris in an engine than an ATF flush. Yes, in theory all of the oil being pumped to the bearings must first pass through the oil filter but it can clog and open the bypass, or the oil galleys can turn loose nasties from their walls, or the crank can splash debris into its bearing clearances from the pan. The point is, a flush disturbs the engine and changes it's lubrication chemistry just long enough to loosen up what should have stayed put if left alone, which basically forces what you're ostensibly flushing the engine to prevent...debris getting where it shouldn't.

I've driven 2 cars to over 250,000 miles and never did a "flush" on any of them. Changed oil every 5,000 miles and both times it was something besides the engine that brought about the car's demise.

Hey, it's your money and car and the US Constitution specifically says you're free to flush your engine with whatever you want, but I would sooner dump sand in the oil filler than flush an engine with ATF and disturb it.

Cheers,
Dave

 

I feel also that the atf flush caused my issues. I had a pretty tight engine, no noises, except lifters at startup. It hasnt even been 500 miles. I can tell you this, the inside of that engine is CLEAN. Now its just broke! Well hopefully the bearings are soft enough not to have damaged the crank.

 

I have to ask has anyone worked around the flywheel or crank sensor on the disco?
If so check the flywheel trigger ring and make sure there are no bent ears on the wheel. Incase you don't know what I am talking about, there is a toothed ring on the flywheel and the crank sensor pin rides in the center of the teeth on the flywheel. if one of the teeth or ears are bent it can contact the crank sensor and cause a tick type noise. I don't know if this is your noise since I can't hear it but it happens all the time. I hope this helps.