so I have and engine noise Ive had in my cuda for probably 10 yrs I cannot seem to figure it out. gave up till I freshened the engine up now it bothers me. first I am a trans and engine tech for dealer I build engines and transes every day for 30 years. master tech at a dealer. of course not building 440s anymore but I know how to build and diagnose engines this one has me stumped. first the engine was a .030 440 stock forged crank and rods trw forged dome pistons the infamous 509 purple cam stick valve train single plane intake hooker headers. mallory dist only use the car nice sunny days and spends 5 months in winter hiding so only gets 3k mi per year on it. never burns any oil plugs always looked great. holley 850 hp 4spd 390 gears. of cource with that cam driveability under 3k sucked but loved the performance. the noise sounds similar to road knock but its not. tried stethescope cant pinpoint it tried killing cyl 1 at a time makes no difference. you hear it loudest standing center in front of car or leaning over engine. but only low at idle if I raised idle to 1100 or more it does away. I can hear it low rpm driving to my trained ear most people riding in car dont hear it. Its kind of a thump sounds like crankshaft speed not cam speed. I replaced fuel pump etc made no diff. so I gave up on it and just drove it. last year I had an oil filter failure and all of a sudden low oil psi so I took engine out and time to rebuild. great Ill find the noise now right?
decided to upgrade some stuff while its apart so had 2 machine shops check pistons after I mic them skirts had no wear on them cyl measured ok only thing I found wrong in engine was 2 and 3 main bearings scared up and crank. not spun just beat up looking. that bearing failure happened that day never had an oil psi problem till that day. doubt that was the noise but couldnt find the noise.

so new build stealth heads had mild pocket cleanup 3 angle valve job new springs to match cam and retainers with 10 deg locks. new cam higher lift mech cam but shorter dur 235 dur 540 lift. using push rod length checker obtained correct push rods and roller rockers. cloyse double roller so whole entire top end of engine is brand new. lower end crank machined .020 .020 clevite bearings rods resized arp bolts. pistons machine shop cleaned up etc arp main bolts oil system mods opened oil holes center 1/2 pickup melling high vol cam bearing rotated with left oil galley plugged .010 hole in plug full time oilling to heads through tubing with a .045 restrictor. 11:1 comp motor runs awesome drive ability even allot better than before thraction is a huge problem now. however after all that the freaking noise is there and now it bothers me casue I never found what it was. so did all the diag again you can hear it in stethescope in the center of oil pan or valley pan you cannot hear it in heads or block really take pow steer belt off no diff take main belt off and you can hear a diff. it again only at low rpms. so I changed water pump and made no diff. cant hear it in WP housing or timing cover or fuel pump shes tucked away for winter so I figure it has to be piston slap because I did not bore it this time. but I would think if it were slap you would see some evidence in the piston skirts. so I am ready to give up and drive it and ignore it again.

no I build a 451 stroker motor for my brothers 32 plym this motor received full treatment brand new everything piston rings bored the works. his has elect fuel pump he has my ported 452 heads his has same kind of noise.
so I tried for the hell of it listening with a screwdriver to the ear trick and noticed I hear in in the number 1 intake runner what seams really loud could it be some kind of intake reversion or something maybe num 1 or 3 cyl since intake ports are kind of shared very wierd noise has me stumped now. seems to have no effect on performance or dive abilty anybody out there have a similar experience?

 

To long of a bolt in the fan to waterpump, damper or flexplate/flywheel?

 

The usual suggestion is to check in the bell housing, have you checked transmission bearing retainer to crankshaft alignment?

 

its a 4spd did not check alignment with a dial indicator like I should have but it def has alignment dowels in it and new style roller bearing dont hear any noise at all in trans or bellhousing area no change in noise when clutch is applied or disengaged and its a lakewood scatter shield. forgot to mention that. planning on changing trans this summer I have a 833 overdrive trans gonna try it out. I will check alignment when I do trans swap. when I did motor last spring the clutch was perfect and all the bearings etc were perfect springs in disc were tight etc. didnt even have to do anything to the flywheel. and arp flywheel bolts and clutch bolts nothing was loose when I did motor.

 

mez -

Exhaust leak at header flange?

Archer

 

Does it have a clutch fan on it?

 

Your Sure your ARP's are not nipping the the Engine Block or windage tray or Oil pick up tube? Just throwing it out there.

 

solid flex fan no clutch has no ac or anything and ran it with power steer belt off made no diff
I thought of the arp bolts and such especially the windage tray possibly hitting something but when I had bare block on engine stand looked for all that stuff and found nothing. no marks on windage tray at all.
also has hemi 6 qt pan on it.
even though I changed the fuel pump to high flow carter while ag and made no difference was thinking of switching to electric this year any way just cause Im pushing new motor hard not sure the mech pump can handle 7k.

 

as senior master tech I fix manifold leaks on a regular basis this is def not a header leak and I use the good percy style gaskets definitely internal to the motor.

 

Fuel pump pushrod?

 

A couple other thought come to mind....
1. Noisy up front on top at front, kind of, and down low.... Harmonic Dampner been replaced and checked for balance and fitness?
2. Relook over the #2 and #3 main bearing shells again. Look at the cap side and look for if it might be scuffed more as if the cap may have been walking?
3. With you stethoscope, Have you listened to the block near the main caps? Check to see if it is more pronounced?
My thoughts on these points are looking for a Line Bore issue or a bent or fractured crankshaft, or even a Dampner that has an issue. Just making noise at this point.
Just food for thought.. And My 2 cents..

 

those are some good points was thinking of trying a sfi approved balancer anyway have no plan to pull motor out at this point again unless its necessary You can hear noise in oil pan in center but not in block or heads. but when you hear it in oil pan kind of sounds like its echoing inside crank case. when you are on top you dont hear it as much standing on side of engine as you do standing right in front of car or leaning over engine with your head over intake. the balancer did fit nice and tight on crank key way is good and bolt is tightened properly.

 

Good Morning,
I was more referring to look at the old bearing Shells if you still had them.
I agree, pulling the motor would suck just for a look at this point.

I can tell it's annoying too you. Being as patient as you are in your field, things that you really have to hunt for just can drive you nuts. Specifically on your own stuff !!!!


On the other hand. Is it possible. That it might be the oil pump Drive & Gear or Pump thumping?

You will find it.... Keep Chipping at it !!

 

the old bearings were destroyed marred up and crank surface thats why I pulled motor the rod bearings were ok just worn some but the oil psi was always around 90 cold and 60 hot and after 10 years one day all of a sudden it was 60 cold and 30 hot but ran fine so I pulled it and found the fram oil filter came apart causing damage. during rebuild it got new pickup new high psi melling pump and drive rod. rods resized with new arp bolts and crank ground was .010 .010 now .020 .020. oil psi is great now like 100 cold and 60 hot. and installed arp main cap bolts at that time clearances were all checked but not line bore as you mentioned earlier. crank spun nice and easy when all mains torqued to spec so if line bore is out its very minor. did the mcandless oil mods to it also to force more oil to mains. litterally everything in motor was new except pistons which showed no signs of wear after 10 years rods which were resized and crank which was reground. thats what puzzle me about the noise so much.

 

I'm sure it will raise it's head at some point and show itself. Thats all I have for now..

 

thanks for your time Kind of hope its gets worse so I can figure it out then again kind of hope it doesnt and I just keep driving it lol

 

Your welcome... Thanks for the question... We love networking and brain storming issues.
Hope it turns out not to be anything....
But as the Drag Racing world says.. (She will Go or She will Blow)….
Have Fun with it. Mopar on Broth'a !!!!!!

 

What was the end play? How was the thrust bearing wear?

 

end play was good only .007 but mains were marred due to the oil failure thats why I pulled it and rebuilt it but the noise is exactly the same from before rebuild to after. new one has between .0015 and .002 on all bearings and .005 end play