Previous Thread
Next Thread
Print Thread
Page 2 of 2 1 2
Re: Strange noise from cam area [Re: varunner] #2562601
10/11/18 09:20 PM
10/11/18 09:20 PM
Joined: Jan 2003
Posts: 14,479
So. Burlington, Vt.
F
fast68plymouth Offline
I Live Here
fast68plymouth  Offline
I Live Here
F

Joined: Jan 2003
Posts: 14,479
So. Burlington, Vt.
My preference is to not run plain cam bearings with over about 900lbs spring load, but I freshened some 572-13 heads last winter where the builder had the heads set up with almost 1200lbs open pressure...... running on plain bearings.
That’s over 2.5 times what you’re running........ plus....... he’s running 1.7 rockers, and the pushrod side of the valvetrain sees the spring load x the rocker ratio.

Your 450 x 1.5 = 675
His 1200 x 1.7 = 2040

I guess what I’m saying is....... I highly doubt it’s the spring load itself that’s the problem.


68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
Re: Strange noise from cam area [Re: varunner] #2562656
10/11/18 11:14 PM
10/11/18 11:14 PM
Joined: Aug 2003
Posts: 43,007
Bend,OR USA
C
Cab_Burge Offline
I Win
Cab_Burge  Offline
I Win
C

Joined: Aug 2003
Posts: 43,007
Bend,OR USA
Originally Posted By varunner
Since I'm building this myself, it may be time to buy a dial bore gauge, cam bearing installation tool and some bearings....It's only money right ?
Your making a outstanding choice on buying those tool so you can control your engine building on the cam bearing and cam fitment up
The only thing else you WILL need is a bearing knife to fix the one in ten BB Mopar blocks that have bad I.D. on some of the cam bearing bore I.D. that makes you need to trim the cam bearing I.D. to get the cam to fit and rotate freely wrench work
Welcome to the Mopar engine building world whistling


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: Strange noise from cam area [Re: varunner] #2562662
10/11/18 11:23 PM
10/11/18 11:23 PM
Joined: Jun 2006
Posts: 660
Virginia
V
varunner Offline OP
mopar
varunner  Offline OP
mopar
V

Joined: Jun 2006
Posts: 660
Virginia
Dwayne, I agree with ya bud.

Thanks Cab, this should be fun. By this point with this engine/car, I should be running out of patience, but as long as I'm learning and making progress, it's all good.

Re: Strange noise from cam area [Re: varunner] #2563703
10/14/18 01:28 AM
10/14/18 01:28 AM
Joined: Jan 2003
Posts: 27,421
Balt. Md
3
383man Offline
Too Many Posts
383man  Offline
Too Many Posts
3

Joined: Jan 2003
Posts: 27,421
Balt. Md
This may not be related to your problem but I ran into a very strange noise from the cam/valvetrain area some years back when working at the Dodge dealer. One of the techs had installed a factory crate eng and it came back about a month later with the cam wiped. The tech installed another cam and after it was running he asked me to listen to the eng with him as I was the shop foreman at the time. It had a strange growling sound in the cam/valvetrain area. I had never heard a sound like this so he installed a can of STP type additive and sent it off as everything checked ok.

Well a week or two later it came back with the cam going out again. So it gets pulled apart and cleaned again with another new cam of the same part # as the parts man just took the cam # of the old RO. Anyway when its done the tech again ask me to listen to it and it sounds like it did before with the strange growling noise and I said we cant let it go until we figure it out. Well after double checking everything we finally found out that parts gave us a roller camshaft for a flat tappet eng. It had flat tappets but they gave us the roller cam as the 318 trucks still used flat tappets that year but some cars used roller cams. That's why it was such a strange noise that we had never heard before as it was flat tappets on a roller cam. Funny thing was after looking closely at the cam after the tech pulled it back out you could tell it was a roller but not so much as you can on a race type roller. Anyway we put the right cam in it and all was well. I don't think that's your problem but it made me think of that because I had never heard a noise like this and could not put my finger on it. Lucky we found it out when double checking all the parts that went in it. Good luck with yours , Ron

Last edited by 383man; 10/14/18 08:40 PM.
Re: Strange noise from cam area [Re: 383man] #2563751
10/14/18 08:41 AM
10/14/18 08:41 AM
Joined: Jun 2006
Posts: 660
Virginia
V
varunner Offline OP
mopar
varunner  Offline OP
mopar
V

Joined: Jun 2006
Posts: 660
Virginia
That's interesting Ron. Do you have a guess on what differences there were to causes the issue ? I would think it is the opening/closing ramps on the roller cam are more aggressive, which caused more friction, hence the wear. I don't know the exact specs on my cam, but it's safe to say it has more aggressive opening and closing ramps than a "stock" cam.

Re: Strange noise from cam area [Re: varunner] #2563752
10/14/18 08:53 AM
10/14/18 08:53 AM
Joined: Jun 2014
Posts: 5,183
P
Porter67 Offline
master
Porter67  Offline
master
P

Joined: Jun 2014
Posts: 5,183
What brand cam bearings?

Re reading it all you posted "The cam bearings are new and show a smooth wear pattern on the lower half of the bearings"

How pronounced is the wear?

Im asking because ive for the last 15 years run the MP cam bearings because I got a big box of them and even with high spring pressure and 7400 they have looked so good ive re used them in beater builds and still not had any major wear issues.

Got any pics of the cam bearing wear? Just a thought.

Re: Strange noise from cam area [Re: varunner] #2563776
10/14/18 10:34 AM
10/14/18 10:34 AM
Joined: Jun 2006
Posts: 660
Virginia
V
varunner Offline OP
mopar
varunner  Offline OP
mopar
V

Joined: Jun 2006
Posts: 660
Virginia
They are durabond bearings. Attached is a picture, they all have contact wear at the bottom, some more some less. until I measure the bore I don't know how much the wear is, probably .001-.002 or so. So how much is too much ???? I haven't looked it up, but around .002 total clearance sounds about right. The issue may also be straightness of the bore....

I looked at a couple of blocks I have, they all have wear at the bottom of the bearings, which makes sense to me as all of the springs are putting force in that direction.

20181008_122243_resized.jpg
Re: Strange noise from cam area [Re: varunner] #2563783
10/14/18 11:15 AM
10/14/18 11:15 AM
Joined: Jan 2003
Posts: 14,479
So. Burlington, Vt.
F
fast68plymouth Offline
I Live Here
fast68plymouth  Offline
I Live Here
F

Joined: Jan 2003
Posts: 14,479
So. Burlington, Vt.
Are those the std or hp cam bearings?

I would have used the coated ones myself.


68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
Re: Strange noise from cam area [Re: fast68plymouth] #2563790
10/14/18 11:41 AM
10/14/18 11:41 AM
Joined: May 2005
Posts: 1,944
Apollo, PA.
B1MAXX Offline
top fuel
B1MAXX  Offline
top fuel

Joined: May 2005
Posts: 1,944
Apollo, PA.
If the the cam spins nice by hand the bearings aren't the issue in my opinion. I've seen some pretty bad cam bearings that were running fine.

Re: Strange noise from cam area [Re: B1MAXX] #2563802
10/14/18 12:05 PM
10/14/18 12:05 PM
Joined: Feb 2005
Posts: 20,116
PA.
pittsburghracer Offline
"Little"John
pittsburghracer  Offline
"Little"John

Joined: Feb 2005
Posts: 20,116
PA.
Originally Posted By B1MAXX
If the the cam spins nice by hand the bearings aren't the issue in my opinion. I've seen some pretty bad cam bearings that were running fine.
m

Every Chevy LS engine eats cam bearing like crazy and I never heard of noise issues


1970 Duster
Edelbrock headed 408
5.984@112.52
422 Indy headed small block
5.982@112.56 mph
9.42@138.27

Livin and lovin life one day at a time




Re: Strange noise from cam area [Re: pittsburghracer] #2563928
10/14/18 04:16 PM
10/14/18 04:16 PM
Joined: Jan 2003
Posts: 8,005
Tulsa OK
Bad340fish Offline
master
Bad340fish  Offline
master

Joined: Jan 2003
Posts: 8,005
Tulsa OK
Originally Posted By pittsburghracer
Originally Posted By B1MAXX
If the the cam spins nice by hand the bearings aren't the issue in my opinion. I've seen some pretty bad cam bearings that were running fine.
m

Every Chevy LS engine eats cam bearing like crazy and I never heard of noise issues


I have heard when working on an LS to never look at the cam bearings, if you do they will be bad lol.


68 Barracuda Formula S 340
87 "Chrysler" Conquest
Re: Strange noise from cam area [Re: varunner] #2565263
10/17/18 10:36 AM
10/17/18 10:36 AM
Joined: Jun 2006
Posts: 660
Virginia
V
varunner Offline OP
mopar
varunner  Offline OP
mopar
V

Joined: Jun 2006
Posts: 660
Virginia
Dwayne, Invoice from barton for the machine work didn't give a p/n for the cam bearings. Do you think the exact type is critical with the issue I'm having ?

Waiting on the cam to be returned from polishing/coating

MicroBlue

FSM calls for .001-.003" oil clearance on the cam journals. Once the cam is back I'll measure and figure out what I have. If it's less than .001" or over .004" I'll replace them. If they're ok, I'll put it all together and see if the noise is still there.

I know the polishing/coating shouldn't be necessary, but it's less than $100 and can't hurt.

Last edited by varunner; 10/17/18 10:37 AM.
Re: Strange noise from cam area [Re: varunner] #2565299
10/17/18 11:59 AM
10/17/18 11:59 AM
Joined: Jan 2003
Posts: 14,479
So. Burlington, Vt.
F
fast68plymouth Offline
I Live Here
fast68plymouth  Offline
I Live Here
F

Joined: Jan 2003
Posts: 14,479
So. Burlington, Vt.
.001 is too tight imo.

I’d want at least .002.

I would have assumed they used the performance series cam bearings at least, but who knows.

I use the coated ones in pretty much everything.


68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
Re: Strange noise from cam area [Re: varunner] #2566144
10/18/18 09:07 PM
10/18/18 09:07 PM
Joined: Jun 2006
Posts: 660
Virginia
V
varunner Offline OP
mopar
varunner  Offline OP
mopar
V

Joined: Jun 2006
Posts: 660
Virginia
Got the cam back from coating, pic below.

I wasn't able to get to all the cam bearings to measure, but the clearances I could get to are from .003-.0038 Installed the cam, it turns nice so I'll assemble it and see if it quiets down.

20181018_181125_resized.jpg
Re: Strange noise from cam area [Re: varunner] #2567076
10/20/18 09:44 PM
10/20/18 09:44 PM
Joined: Jun 2006
Posts: 660
Virginia
V
varunner Offline OP
mopar
varunner  Offline OP
mopar
V

Joined: Jun 2006
Posts: 660
Virginia
Put it together today and no noise. The coating is supposed to hold onto the oil better. So between a better finish and more oil on the surface, less friction and no noise. IDK, but that's the only explanation I have. Motor is together and hopefully install and fire it up tomorrow.

Re: Strange noise from cam area [Re: varunner] #2567085
10/20/18 10:05 PM
10/20/18 10:05 PM
Joined: Jan 2003
Posts: 14,479
So. Burlington, Vt.
F
fast68plymouth Offline
I Live Here
fast68plymouth  Offline
I Live Here
F

Joined: Jan 2003
Posts: 14,479
So. Burlington, Vt.
up


68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
Page 2 of 2 1 2






Powered by UBB.threads™ PHP Forum Software 7.7.1