Engine noise

Cobradad · #1 (**permalink**) 06-05-2011, 02:30 PM

Thanks for all the input. Oil and filter were changed to redline synthetic Bill gave me and has about 650 miles on it. Patrickt, the suggestion of the stethoscope made all the difference. Passenger side, all cylinders have the valves purring like the probverbial kitten. Cylinder 5 and 8 a little louder, 6 and 7 making a heck of a racket. Is it odd to be fine, and suddenly have valves on two cylinders go out like that. As I mentioned earlier, all engine vitals are great and idle is unaffected so I hope it is nothing more serious than a valve adjustment. Time to pull the valve covers. Thanks again for all the responses.
Bob W.

patrickt · #2 (**permalink**) 06-05-2011, 02:53 PM

Interesting that the sound is only on one side of the engine, and strongest in the middle of the bank and less so on the ends. Pull the cover on that side only, adjust the valves, but pay particular attention to the springs, retainers, keepers, and arms on numbers 5 and 6. Pull your coil wire and have someone crank the engine while you stare at those four valves.

RICK LAKE · #3 (**permalink**) 06-05-2011, 05:49 PM

CobraDad Make sure that the oil holes are all open and check the shafts for cracks at the hole where the holddown bolts or studs are. Check for galling, blueing of the shafts. Look this over hard for possible failure. This is strange thing fo 1 side of the motor to have problems on this side and nothing wrong on the low side. Take your time and be careful before reassembly of the motor. Rick L.

mrmustang · #4 (**permalink**) 06-05-2011, 06:19 PM

Quote:

Originally Posted by Cobradad

Thanks for all the input. Oil and filter were changed to redline synthetic Bill gave me and has about 650 miles on it. Patrickt, the suggestion of the stethoscope made all the difference. Passenger side, all cylinders have the valves purring like the probverbial kitten. Cylinder 5 and 8 a little louder, 6 and 7 making a heck of a racket. Is it odd to be fine, and suddenly have valves on two cylinders go out like that. As I mentioned earlier, all engine vitals are great and idle is unaffected so I hope it is nothing more serious than a valve adjustment. Time to pull the valve covers. Thanks again for all the responses.
Bob W.

Did you miss a shift and/or over rev the motor at all ?

Bill S.

patrickt · #5 (**permalink**) 06-05-2011, 06:38 PM

Quote:

Originally Posted by mrmustang

Did you miss a shift and/or over rev the motor at all?

WTF Bill? You sold him a SO with no rev limiter?

mrmustang · #6 (**permalink**) 06-05-2011, 07:59 PM

Quote:

Originally Posted by patrickt

WTF Bill? You sold him a SO with no rev limiter?

I honestly cannot remember if there is a 6 or 6AL MSD box under the dash. Personally, I never over rev the motors in my cars, especially in a 427 big block as all the torque and HP are on the lower end of the spectrum. Even the Mod motor in my fia has yet to see abnormally high RPM's even though it appears to like it higher up in the RPM band........

Bill S.

patrickt · #7 (**permalink**) 06-07-2011, 10:30 AM

Here's a decent valve lash thread: Valve lash questions

And here's a couple of pics I took a while back regarding turning the engine. I've since replaced the crank bolt with one of ARP's new bolts that takes a half inch ratchet directly (no more socket needed) -- this is really an easy way to turn your engine and safer than bumping it with a remote starter.

Cobradad · #8 (**permalink**) 06-06-2011, 08:13 AM

No, no missed shifts. Ive been driving it very sedately. I don't think its seen 5K rpm. With light weight, short wheelbase and alot of hp, I've tried not to be stupid so far. I was just driving home from my office and heard the racket.

mrmustang · #9 (**permalink**) 06-06-2011, 08:42 AM

Quote:

Originally Posted by Cobradad

No, no missed shifts. Ive been driving it very sedately. I don't think its seen 5K rpm. With light weight, short wheelbase and alot of hp, I've tried not to be stupid so far. I was just driving home from my office and heard the racket.

Ok, that eliminates that, have you had a chance to pull the valve covers off yet as I am real curious to get to the bottom of this.

Bill S.

DanEC · #10 (**permalink**) 06-06-2011, 11:43 AM

Just to make sure you covered all the easy stuff first - could it be an exhaust leak on that bank. Header bolts have a way of backing off and gaskets or sealer get blown out. Itsi bitsi chance it could be something like that.

Cobradad · #11 (**permalink**) 06-07-2011, 09:48 AM

I used an automotive stethoscope to listen to each cylinder. Definately #'s 5 & 6 are much louder than the rest. I have no idea of the proper settings for the particular cam in the car. I intend to pull the valve covers over the weekend and visually inspect whats going on. Not sure if I will attempt the adjustment myself, its been over 30 years since I did one. To that end, any ERA folks out there have a reccomended shop. I live just outside of Coatesville, PA. I know Bill used a shop in Pottstown. Wouldn't mind something in West Chester. Thanks for every one's help.
Bob W

patrickt · #12 (**permalink**) 06-07-2011, 10:20 AM

Quote:

Originally Posted by Cobradad

I have no idea of the proper settings for the particular cam in the car. I intend to pull the valve covers over the weekend and visually inspect whats going on. Not sure if I will attempt the adjustment myself, its been over 30 years since I did one.

Bob, you could always just check the other valves with a feeler gauge to see what the lash is on them. But what I would do for a decent starting point on valve lash for that particular engine is if those TP heads are aluminum set the lash for both intake and exhaust COLD at around .018, if they're iron, set them COLD to about .026 -- that's close enough for now. The only trick to adjusting solid valves is to make sure you have the engine rotated so that you're on the heel of the lobe. It's been discussed many times here, I'll see if I can find you the easiest thread. What I do to rotate the valvetrain is just put my half-inch ratchet on the crank bolt and then slip the aluminum handle from my jack over that so that it's effectively a three foot long ratchet wrench. That makes rotating the engine very easy and you don't have to pull the spark plugs either.

pjmoore2003 · #13 (**permalink**) 06-07-2011, 10:42 AM

Quote:

Originally Posted by DanEC

Just to make sure you covered all the easy stuff first - could it be an exhaust leak on that bank. Header bolts have a way of backing off and gaskets or sealer get blown out. Itsi bitsi chance it could be something like that.

Worth giving a good check

I dont have an SO engine but I just went through this. Friends thought it was valvetrain, but I found a header bolt rattled out causing gasket to fail. It's funny how bad an engine can sound with a bad gasket.

Cobradad · #14 (**permalink**) 06-08-2011, 02:07 PM

Thanks for all the info. Patrickt, great summary of valve lash adjustment. I figured I would use a socket and pipe to rotate the engine. I never was any good at bumping the engine with the starter. I was going to make sure I used neoprene valve cover gaskets so I can reuse them since the covers may be off once in a while. Bill, do you know if the heads are iron or aluminum? Can't say that I've really checked them out yet. I will check the header bolts just to cover all the bases. This is what makes this forum so great. I have been reading and following things for probably two years before I bought the car. Hopefully I have the time to look things over this weekend and I will let you all know what I find. Thanks again.
Bob W

patrickt · #15 (**permalink**) 06-08-2011, 02:10 PM

Quote:

Originally Posted by Cobradad

Bill, do you know if the heads are iron or aluminum?

Bob, don't trust Bill.

Get a magnet off the front of your refrigerator (that's probably holding up one of the kids' pictures) and put it on the head. If it sticks, it's iron, it it doesn't, it's aluminum.

mrmustang · #16 (**permalink**) 06-08-2011, 07:34 PM

Quote:

Originally Posted by Cobradad

Thanks for all the info. Patrickt, great summary of valve lash adjustment. I figured I would use a socket and pipe to rotate the engine. I never was any good at bumping the engine with the starter. I was going to make sure I used neoprene valve cover gaskets so I can reuse them since the covers may be off once in a while. Bill, do you know if the heads are iron or aluminum? Can't say that I've really checked them out yet. I will check the header bolts just to cover all the bases. This is what makes this forum so great. I have been reading and following things for probably two years before I bought the car. Hopefully I have the time to look things over this weekend and I will let you all know what I find. Thanks again.
Bob W

Bob, beware of Patrick bearing gifts from afar

Heads are iron "Tunnel Port" heads.

Bill S.

patrickt · #17 (**permalink**) 06-13-2011, 11:46 AM

Quote:

Originally Posted by Cobradad

Hopefully I have the time to look things over this weekend and I will let you all know what I find. Thanks again.

Bob, did you get a chance to eyeball your valve train over the weekend? Hi-res pics are always helpful as well you know.

Cobradad · #18 (**permalink**) 06-13-2011, 03:42 PM

Hi Patrick
Did not. Wives have a way of making those lists....
The list of cars I need to look at is growing. Daughter informs me the ac on my truck that she is driving is not working and the Mustang threw a code I now need to check. In my mind the cobra should be first on the list. I think I need to tell them I keep the cobra, everyone else rides a horse. I will let you all now about the cobra when I get a chance. Inquiring minds want to know. Thanks.
Bob