Scored Main Cap Bearing - Ouch

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Us
Marcohotrod said:
oil holes are chamfered. and oil to #5 is back from the filter directly, 1-4 goes a different path. did junk in the pump go thru a cheap filter?
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ed a Mopar Filter, maybe not the Best? I have already thrown away the first filter I am now on my second one.
 
pittsburghracer said:
Put a 1/8 rod down through the oil pressure sending unit hole on top the rear of the block. If it falls straight through the block (with the rear main cap off) the 9/16 plug was never installed. If you fail to install this plug oil isn’t diverted to the oil filter.
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Thanks I will check that
 
I'd pull the oil pump cover and get the feeler gauges also. If it made it out of the bearing, it made it into the pump maybe.
 
darn nm and 512 what I would have said
crocus cloth NO SCOTCHBRIGHT
how was the filter ops saw it wa tossed
 
Ok more info. The oil hole in journal is not really chamfered very much, in fact it looks like it may have caused the problem. How do I address it? Now for the stupid error on my part. The bolts I used were a little bit to long for the flywheel and guess what, it rubbed the rear bearing cap and ground a groove in it and the bolts down, see pic. I dont want to change the bolts so do I 1) have a little bigger groove milled in the cap for clearance or leave it alone since it is now clearanced? The picture of the main cap is the one next to the rear cap. No grooves that your fingernail would hang on. Since I am ordering new main bearings do I replace them all one at a time since I have them or just do the rear and leave well enough alone? Thanks all you have been very good about helping me.

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knock it down with a file, clean the oil passage with a Q tip and install a new bearing. Run it....
 
Let’s think about this guys slowly before we tell him to send it. You gotta check the other bearings, you gotta check to see if by running those long bolts he didn’t do damage to the thrust bearing. Gotta make sure oil is going to the oil filter, gotta flush the engine some, should install a magnet in the pan. Should check a rod bearing or two.
 
TrailBeast said:
I have done them in the engine and in the car a bunch of times without a problem.
A fine (600) crocus cloth strip with a little oil on it and make sure the oil hole in the crank is clean after.
Q tips for that.
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Yes.... It's not often my cranks see a crank polisher anymore unless it is underground at a shop. Have polished gobs of journals with 400 & 600 Wet or Dri..... have even taken them down .001 for added oil clearance with wet-or-dri and leather strap. Don't get carried away; shape won't be perfectly round and 100% taper free that way but within a few 10-thousandths. (My measured data...)

Cant' say I recall doing on in car though. Get the upper bearing shell out and wrap the abrasive cut to a proper width strip around the crank and go to town; rotate crank regularly. Just keep things clean in the oil holes and shine it up 90-95%; no need to get each tiny groove out.

Inspection of other journals ought to tell a lot.
 
pittsburghracer said:
Put a 1/8 rod down through the oil pressure sending unit hole on top the rear of the block. If it falls straight through the block (with the rear main cap off) the 9/16 plug was never installed. If you fail to install this plug oil isn’t diverted to the oil filter.
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Or poke up from the bottom... the plug is something like 2" above the oil pump hole in the block (from the parting line).
IIRC... such a rod ought to drop something around 7-1/2" to 7-5/8" from oil pressure sensor hole to that plug. Measure and check back in and someone can check look it up.
 
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I couldn’t find one inch wide 320 or 380 paper so I got mine from Amazon in like two days. Leather strap is from the horse supply area at Tractor Supply.
 
Oldmanmopar said:
Everything my son works on is cleaned before it hits the machines and after. He will not put parts that don't look like new in the mills. Also all parts are laid on clean towels and then covered at night. Like your putting the kids to bed. He sprays every machine down with CRC lube every night. I once set a coffee on the mill. He flipped out. Dave leaned on it one time and he flipped out. That is the kind of shop you want to take a motor to. He learned this working for an old time machinist . Not from me that's for sure.

Look for a clean machinist in your area that cares about their reputation.

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Tape on the pistons for checking piston to cylinder wall clearance without scratching? Nice! I like what you guys do!
 
So what is the knurling pattern for on the rear main seal. My crank is polished like the rest of the journals. I looked at some Scat cranks and they appear to be polished also.
 
blewbyoutobad said:
So what is the knurling pattern for on the rear main seal. My crank is polished like the rest of the journals. I looked at some Scat cranks and they appear to be polished also.
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To make the oil travel back towards the inside of the engine. Splash will keep the seal lubed but it doesn't need to be flooded.
 
So what is the knurling pattern for on the rear main seal. My crank is polished like the rest of the journals. I looked at some Scat cranks and they appear to be polished also.
pittsburghracer said:
Let’s think about this guys slowly before we tell him to send it. You gotta check the other bearings, you gotta check to see if by running those long bolts he didn’t do damage to the thrust bearing. Gotta make sure oil is going to the oil filter, gotta flush the engine some, should install a magnet in the pan. Should check a rod bearing or two.
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I after going outside in a little bit and check some rod bearings. Can someone explain to me thrust bearing, how it works and which one is it.
 
blewbyoutobad said:
So what is the knurling pattern for on the rear main seal. My crank is polished like the rest of the journals. I looked at some Scat cranks and they appear to be polished also.

I after going outside in a little bit and check some rod bearings. Can someone explain to me thrust bearing, how it works and which one is it.
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Your thrust bearing is number 3 and locate the crank in the block. Most manuals say .003-.005 thrust clearance (best checked with a dial indicator) I set my race clearance for the thrust at .005 plus. You can check this with a screwdriver and feeler gauges but it’s not as accurate
 
That thrust bearing is shot if there was that much pressure on the bearing from the bolts rubbing the cap . There was no oil clearance on the thrust side. Listen All BS aside pull the motor . turn it upside down and pull the crank pushing the pistons to the top of the bore. You will need a timing gasket set and a oil pan set. and bearings, Recheck all the clearances on the crank and replace all the bearings and the oil pump.

You will not be sorry for doing this. You can take the crank and have it polished. Have it mic'd King and Clevite sell bearings to any size to bring the clearances in. My son just bought a set to make up .002 on the recommended clearance. If you need the right bolts for the flywheel or flexplate buy them. Or give me your address I'll send you some. Pay the shipping after you receive them.

Put a dial indicator on the crank and move it front to back you'll see that thrust bearing is bad. Also you won't drop the crank enough to do the work with the trans in and the timing chain on. Why ruin what may still be good . Do it right.
 
pittsburghracer said:
Your thrust bearing is number 3 and locate the crank in the block. Most manuals say .003-.005 thrust clearance (best checked with a dial indicator) I set my race clearance for the thrust at .005 plus. You can check this with a screwdriver and feeler gauges but it’s not as accurate[/QUOTE
I will check it and see where its at.
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toolmanmike said:
Tape on the pistons for checking piston to cylinder wall clearance without scratching? Nice! I like what you guys do!
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The tape is on there to impregnate dry lube in a special blast cabinet after removing the junk worn through moly you see on the other pistons. If you look close the is a powder coating tape under the masking tape. Some motors get the dry lube on the top of the piston surface also. Depending how much money you have. Nothing sticks to or wears this off. Very expensive. Used on valves also and all internal parts if you have the money.

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In post #13, the rear-most portion of the crank looks discolored (as in turning purple from heat), if those bolts rubbing on the back of the block caused that amount of strain, the front face of the thrust bearing (#3) will also be chewed to ****, there's your engine contaminant. The heat from those rubbing bolts would also have melted the rear seal! Take #3 cap off and see what damage is done to the thrust surface of the crank.
 
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