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Re: Bad Main bearing cause? [Re: VoodooCLD] #1191196 03/15/12 03:12 PM 03/15/12 03:12 PM
Joined: Aug 2003 Posts: 954 garnett kansas rhad super stock
rhad super stock Joined: Aug 2003 Posts: 954 garnett kansas	dont the main caps have the number cast into them?

Re: Bad Main bearing cause? [Re: rhad] #1191197 03/15/12 03:19 PM 03/15/12 03:19 PM
Joined: Oct 2011 Posts: 460 Oklahoma V VoodooCLD OP mopar
VoodooCLD OP mopar V Joined: Oct 2011 Posts: 460 Oklahoma	I'll have to check when i get home. I thought that there were some stampings on the caps, but for some reason i thought they all said 8. I'll double check when i get home. On a side note, the rod bearings were worn in places as well. They were not nearly as bad as the crank bearings, but i could see a little copper in places. If the line bore was off, it wouldn't effect the rod bearings too much. So i'm again wondering if it was just dirty oil, and poor oiling, and maybee i could get away with just a replace of bearings. going to pick up the crankshaft tonight, it got turned 20/20 with no problems.

Re: Bad Main bearing cause? [Re: VoodooCLD] #1191198 03/15/12 04:17 PM 03/15/12 04:17 PM
Joined: Jul 2009 Posts: 413 Norway (old world) Oyvind Mopar mopar
Oyvind Mopar mopar Joined: Jul 2009 Posts: 413 Norway (old world)	Quote: Ok so for an update, i stripped the entire motor down and noticed that there was a chunk taken out of one of the cam lobes. I had a 360 stroker that had same bearing issues due to 3 worn-out camlobes had sent the trash through the mains, chewed them up badly first. Rodbearings looked better. Had to regrind the crank etc. after a full tear down. Same has happened with other engines that ruined camlobes. Just to let you know. Hope it works out for you!

Re: Bad Main bearing cause? [Re: Oyvind Mopar] #1191199 03/15/12 04:36 PM 03/15/12 04:36 PM
Joined: Oct 2011 Posts: 460 Oklahoma V VoodooCLD OP mopar
VoodooCLD OP mopar V Joined: Oct 2011 Posts: 460 Oklahoma	Quote: Quote: Ok so for an update, i stripped the entire motor down and noticed that there was a chunk taken out of one of the cam lobes. I had a 360 stroker that had same bearing issues due to 3 worn-out camlobes had sent the trash through the mains, chewed them up badly first. Rodbearings looked better. Had to regrind the crank etc. after a full tear down. Same has happened with other engines that ruined camlobes. Just to let you know. Hope it works out for you! So you think i'll be alright with just turning the crank down and installing new bearings? (i'm also gonna hone, and put new rings in) And what did you do to fix this, just install a higher quality cam? Mine looks like the original. Last edited by VoodooCLD; 03/15/12 04:38 PM.

Re: Bad Main bearing cause? [Re: JohnRR] #1191200 03/15/12 05:56 PM 03/15/12 05:56 PM
Joined: Mar 2008 Posts: 5,746 Ontario, Canada Dodgem master
Dodgem master Joined: Mar 2008 Posts: 5,746 Ontario, Canada	Interesting , just did a build with a 63HP and didn't experience any of this . You sure you have an HP and not and HV they sell 3 stock, High volume HV and High Pressure HV. When I went to the speed shop with the HP he said I will not sell them just HV or stock. He said his book said industrial motor only with canister type filter. And yes I checked the bypass even put a stock spring in which did not help much at all. Put one of my used mopar high volumes on and it was fine so then got a new HV and it was fine the gears are totally different! Well I see the melling hp is just a stock pump with stronger bypass spring?? This one years ago had tall gears like a high volume but real sharp?? may have been a Federal Mogal bin a while but it was dangerous. took out 3 140 hp oil gauges as well as filters. Last edited by Dodgem; 03/15/12 06:10 PM.

Re: Bad Main bearing cause? [Re: Dodgem] #1191201 03/15/12 06:01 PM 03/15/12 06:01 PM
Joined: Oct 2011 Posts: 460 Oklahoma V VoodooCLD OP mopar
VoodooCLD OP mopar V Joined: Oct 2011 Posts: 460 Oklahoma	Quote: Interesting , just did a build with a 63HP and didn't experience any of this . You sure you have an HP and not and HV they sell 3 stock, High volume HV and High Pressure HV. When I went to the speed shop with the HP he said I will not sell them just HV or stock. He said his book said industrial motor only with canister type filter. And yes I checked the bypass even put a stock spring in which did not help much at all. Put one of my used mopar high volumes on and it was fine so then got a new HV and it was fine the gears are totally different! I know you were talking to him, but mine has a tag on it that's attached to one of the bolts that says m63hp, and "cal 10" is cast in the side of it. And dodgem means, "they sell 3 types - stock, High volume HV, and High Pressure HP" Last edited by VoodooCLD; 03/15/12 06:03 PM.

Re: Bad Main bearing cause? [Re: Dodgem] #1191202 03/15/12 07:52 PM 03/15/12 07:52 PM
Joined: Jan 2003 Posts: 74,978 U.S.S.A. JohnRR I Win
JohnRR I Win Joined: Jan 2003 Posts: 74,978 U.S.S.A.	Quote: Quote: Interesting , just did a build with a 63HP and didn't experience any of this . You sure you have an HP and not and HV they sell 3 stock, High volume HV and High Pressure HV. When I went to the speed shop with the HP he said I will not sell them just HV or stock. He said his book said industrial motor only with canister type filter. And yes I checked the bypass even put a stock spring in which did not help much at all. Put one of my used mopar high volumes on and it was fine so then got a new HV and it was fine the gears are totally different! Well I see the melling hp is just a stock pump with stronger bypass spring?? This one years ago had tall gears like a high volume but real sharp?? may have been a Federal Mogal bin a while but it was dangerous. took out 3 140 hp oil gauges as well as filters. I am 99% sure it was a HP , will have to check the invoice now ... I t did have a leak and I had to lap the plate the oil filter attaches to because it looked like it was surfaced with a rock. Standard height stock looking rotors , never seen one with the sharp rotor till someone posted the picture of the new style that is coming out?

Re: Bad Main bearing cause? [Re: rhad] #1191203 03/15/12 07:58 PM 03/15/12 07:58 PM
Joined: Jan 2003 Posts: 74,978 U.S.S.A. JohnRR I Win
JohnRR I Win Joined: Jan 2003 Posts: 74,978 U.S.S.A.	Quote: dont the main caps have the number cast into them? Yes the caps are numbered.

Re: Bad Main bearing cause? [Re: VoodooCLD] #1191204 03/15/12 08:02 PM 03/15/12 08:02 PM
Joined: Jul 2009 Posts: 413 Norway (old world) Oyvind Mopar mopar
Oyvind Mopar mopar Joined: Jul 2009 Posts: 413 Norway (old world)	Quote: Quote: Quote: Ok so for an update, i stripped the entire motor down and noticed that there was a chunk taken out of one of the cam lobes. I had a 360 stroker that had same bearing issues due to 3 worn-out camlobes had sent the trash through the mains, chewed them up badly first. Rodbearings looked better. Had to regrind the crank etc. after a full tear down. Same has happened with other engines that ruined camlobes. Just to let you know. Hope it works out for you! So you think i'll be alright with just turning the crank down and installing new bearings? (i'm also gonna hone, and put new rings in) And what did you do to fix this, just install a higher quality cam? Mine looks like the original. I do not know how to check the material quality of the cam and lifters. It is a gamble when using stock type parts. I used another block, bored it and put in the old pistons, after removing all iron particles stuck in the skirts. Then new rings. And, using a high Zn / Ph oil and the comp cams additive as well. The old 360 block can be reused (have it for another project) after honing, it cleared out quite well with only .001" removed. Only a few tiny stripes left. I changed the block because of a low oil pressure issue, and suspected the lifterholes to be too slack. They were no worse than the other, but I did not take chances. The hivolume oilpump was destroyed by all the debris going through. The engine was run for some time with the damaged lobes, and I think this extended running with the debris destroyed the engine. Camwear did not stop on the broken lobes, and finally the engine started misfiring on the cylinders with low lift. Then it was all detected when I got the vehicle in for service/troubleshooting. I hate this situation with the cams, lifters and oil. In the past I never take chances with the oil, and use the sloppiest valvesprings possible for the cam and max rpm for these street engines. You could use lifters with lube holes, and nitrided cams (I thought they all were nitrided, but obviuosly not good enough, so extra cash is needed to avoid being cheated) and you end up with something approaching a roller in cost. Still this could be better than a roller failure in a high mile/useage street engine. I also had an engine with a 590 cam broken in at the dyno, checked/adjusted valves, OK, and after the dyno session one lobe and lifter was gone. I guess the oil used was not good enough, and the quality of the parts is questionable. I am so afraid of this stuff that I rather buy a slightly used cam with lifters in sorted order, to be sure it has survived the first runs. I build engines for a living, and the profit gets negative when such things happen. Good Luck!!!

Re: Bad Main bearing cause? [Re: Oyvind Mopar] #1191205 03/15/12 08:52 PM 03/15/12 08:52 PM
Joined: Oct 2011 Posts: 460 Oklahoma V VoodooCLD OP mopar
VoodooCLD OP mopar V Joined: Oct 2011 Posts: 460 Oklahoma	Finally some real news. I took a second look at the caps, and while they were in the correct numerical order. THEY WERE NUMBERED BACKWARDS! The number 5 cap was at the front of the engine. (i believe this is backwards right?) In any case, if i were to just get new bearings and put it back together in the correct order (1 being at the front of the engine) would it work alright? I'd really like to not have it line bored since no one here in town does it, but i don't want to be tearing down the engine again. Also are the numbers on the main caps supposed to go on the driver or passenger side? Another thing, when i was at the shop i measured the rod journals and after machining they measured 2.354. I asked why they were 6 thousands under a .020 over, and he showed me a book that said stock journals were 2.374. I assumed that the book was right, but now every where i'm reading says that stock journals are 2.380, and .020 under would be 2.360!!!! WHAT IS THE STOCK ROD JOURNAL SIZE ON a (cast 1970) 1971 mopar 383? and what would a .020 under be. No websights selling bearings show the exact size. EDIT: I have found even more sources that state the stock rod journals are 2.375". So maybee his book was right after all (in don taylors big block mopar engines, he states 2.380" and that was the first book i grabbed). And even more, they actually measured about 2.3545. So i now feel he might have done a really good job. Last edited by VoodooCLD; 03/15/12 09:03 PM.

Re: Bad Main bearing cause? [Re: VoodooCLD] #1191206 03/15/12 09:58 PM 03/15/12 09:58 PM
Joined: Jan 2003 Posts: 10,707 North Dakota 6PakBee I Live Here
6PakBee I Live Here Joined: Jan 2003 Posts: 10,707 North Dakota	You have to be kidding me. Backwards? Anyway you must have the engine out of the car? If the crank is OK, with the pan side facing up and new upper bearings in the #1 and #5 position in the block, spin the crank and check the runout on the #3 bearing with a dial indicator. Should be less than 0.001" TIR. Then put the rest of the upper bearings in and plastigauge all of the main journals. A change in clearance from one end to the other typically means a line bore job. If the clearances are close, assemble all the bearings and with lube on them check how freely the crank turns. A straight crank in a straight block requires very little effort to get it to spin. BTW, the main caps are offset and will fit in the register only one way. "We live in a time when intelligent people are being silenced so that stupid people won't be offended".

Re: Bad Main bearing cause? [Re: Dodgem] #1191207 03/15/12 11:01 PM 03/15/12 11:01 PM
Joined: Feb 2005 Posts: 4,311 Prospect, PA BSB67 master
BSB67 master Joined: Feb 2005 Posts: 4,311 Prospect, PA	Quote: You don't want a 63HP they will put out huge pressure 140 + you want a 63HV gives volume at way less pressure. Think the Hp is for industrial motors like water pumps that run 24/7 at 4000 rpm. with a canaster style filter. took one off a friends 440 would blow the filters up and off sometimes and buried the 140 oil pressure gauge. Sharp pump gears as opposed to the rounded ones If that happens, it's not due to the HP pump/spring. Either the relief valve was stuck, or the pump volume was greater than the relief valve could bleed off. Of coures the motor would need to be pretty tight as well. The HP is all I use anymore. Last edited by BSB67; 03/15/12 11:03 PM.

Re: Bad Main bearing cause? [Re: VoodooCLD] #1191208 03/16/12 12:24 AM 03/16/12 12:24 AM
Joined: Aug 2003 Posts: 43,127 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,127 Bend,OR USA	Number one main cap is in the front of the motor by the oil pump, the rod journals should be 2.375 stock, Mopar allows +.0005 or - .0005 for the factory tolerances, 2.3745 to 2.3755, .020 under should be 2.7555 tp 2.37545 Get the new main bearings and fix the crankshaft and then install the upper main bearings(the ones with the oil holes) in the block and then lay the crankshaft in them,use oil on the main bearings and crankshaft and then spin it, install the main caps so that two bearing retaining tangs are facing each other and then tighten the mains down to 85 Ft lbs, I use three increments, 30 lbs, 60 lbs and then 80 lbs. ,except number three,leave it loose until your ready to set the end play, and spin the crank. No main seal or timing cover seal yet. It should spin very easily by grabbing the crank snout with one hand and spin it If it doesn't spin easily find out why. You can also try spinning the crank on each main bearing as you tighten them down, just in case Let us know what you find, BTW, the main caps should not fall into the main saddles, they should have to be tapped in or push in very hard by hand I use a soft faced mallet to tap them into place Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: Bad Main bearing cause? [Re: Cab_Burge] #1191209 03/16/12 07:50 PM 03/16/12 07:50 PM
Joined: Oct 2011 Posts: 460 Oklahoma V VoodooCLD OP mopar
VoodooCLD OP mopar V Joined: Oct 2011 Posts: 460 Oklahoma	Cab thank you for the info. 6pak i don't understand how checking the runout on the crank will determine if my block is still in line. Seems like that would only check that the crank isn't warped?

Re: Bad Main bearing cause? [Re: VoodooCLD] #1191210 03/16/12 08:52 PM 03/16/12 08:52 PM
Joined: Jan 2003 Posts: 10,707 North Dakota 6PakBee I Live Here
6PakBee I Live Here Joined: Jan 2003 Posts: 10,707 North Dakota	Quote: Cab thank you for the info. 6pak i don't understand how checking the runout on the crank will determine if my block is still in line. Seems like that would only check that the crank isn't warped? You are absolutely correct. If you check the crank and the crank is true (straight), then you can use it as a try bar to check the alignment of the main bearing bores. Look at it this way, if you assemble the bottom end with new bearings and the crank is hard to turn; do you have a bent crank or does your block need to be line bored because the main bores are out of alignment? If you check as I have indicated you'll know the answer. "We live in a time when intelligent people are being silenced so that stupid people won't be offended".

Re: Bad Main bearing cause? [Re: 6PakBee] #1191211 03/16/12 10:50 PM 03/16/12 10:50 PM
Joined: Oct 2011 Posts: 460 Oklahoma V VoodooCLD OP mopar
VoodooCLD OP mopar V Joined: Oct 2011 Posts: 460 Oklahoma	Quote: Quote: Cab thank you for the info. 6pak i don't understand how checking the runout on the crank will determine if my block is still in line. Seems like that would only check that the crank isn't warped? You are absolutely correct. If you check the crank and the crank is true (straight), then you can use it as a try bar to check the alignment of the main bearing bores. Look at it this way, if you assemble the bottom end with new bearings and the crank is hard to turn; do you have a bent crank or does your block need to be line bored because the main bores are out of alignment? If you check as I have indicated you'll know the answer. Gotcha, so as far as checking the line bore you basically just make sure the crank spins freely.. thanks

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