Damage to my Crane Rockers & Shafts (pics inside)

Damage to my Crane Rockers & Shafts (pics inside) - 10/04/09 03:42 PM

Well here are some pics of the damage to one of my Crane rocker shafts and rocker. The depth of the the damage is very shallow as it probably is not even 002 or .001 deep if even that.

The damage on the shafts is on the underside only where the oil holes are and in the rocker pic it shows the damage only in the bottom part of the rocker also.

As you can see from the pics every one of the rockers has about the same amount of damage.

What could be the cause of this???

I have a brand new set of Harland Sharp shafts and rockers sitting here but I dont want to install them without knowing what could have caused the damage to the cranes. I dont want to ruin the sharps also.

This is the top portion of the rocker shaft.

This is the bottom part of the shaft.

Pic of the damage to inside bottom of the rocker arm.

Posted By: CompWedgeEngines

Re: Damage to my Crane Rockers & Shafts (pics inside) - 10/04/09 03:55 PM

What is , open spring pressure, RPM operating range, useage of car, and cylinder heads?

How old and how long have these been running?

What prompted the inspection?

Posted By: Tig

Re: Damage to my Crane Rockers & Shafts (pics inside) - 10/04/09 04:06 PM

What heads are these on? Might be oil starvation if pic # 2 shows the even bank of rockers on a stock iorn head. As suggested it could be down to spring pressure too.
Looks like you have some small geometry / pushrod length issues if you run the adjusters with that much thread showing, though this wouldn't cause the damage.
Just my

hope this helps.

Posted By: Blakcharger440

Re: Damage to my Crane Rockers & Shafts (pics inside) - 10/04/09 04:11 PM

Quote:

What is , open spring pressure, RPM operating range, useage of car, and cylinder heads?

How old and how long have these been running?

What prompted the inspection?

The cam is a Hughes solid 579/587 256/260 with open spring pressure is 370 @ 1.280

I doubt that I even have 100 miles on this engine with Stealth aluminum heads.
It is supposed to be a street/strip car.

I started to make sure my lash was adjusted properly and I noticed that my oil was blackened and had a very,very fine paste deposits on parts of my cylinder head.

Other than on the dyno I have never spun the engine over 4000 RPM as I wanted to make sure everything was going fine before doing so.

Posted By: Bob_Coomer

Re: Damage to my Crane Rockers & Shafts (pics inside) - 10/04/09 04:12 PM

Banana grooved rockers would help. There is a guy on ebay that sells coated Moly shafts, that look very nice.
The Harlands are needle bearings so you should have much trouble.
How many miles were on these?

Posted By: Anonymous

Post deleted by Defbob - 10/04/09 08:23 PM

Posted By: Blakcharger440

Re: Damage to my Crane Rockers & Shafts (pics inside) - 10/04/09 09:14 PM

Quote:

My gut tells me you are lacking oil pressure to your rocker shafts. Those feed holes aren't restricted, are they? If it were me, I would verify that good pressure is coming out of the feed holes, with the shafts removed.

How do I make sure I am getting oil to the rocker shafts? Right now I have the intake and carb off.

Posted By: Jwilli500

Re: Damage to my Crane Rockers & Shafts (pics inside) - 10/04/09 09:17 PM

I hafta agree with Duster Dave.

Quote:

My gut tells me you are lacking oil pressure to your rocker shafts. Those feed holes aren't restricted, are they? If it were me, I would verify that good pressure is coming out of the feed holes, with the shafts removed.

Posted By: Chris2581

Re: Damage to my Crane Rockers & Shafts (pics inside) - 10/04/09 09:31 PM

Quote:

How do I make sure I am getting oil to the rocker shafts? Right now I have the intake and carb off.

Pull the distributor and drive gear and spin the oil pump with a priming tool.You'll need to rotate the engine at times in between.Or you can use a remote starter button and do it that way with out pulling the dizzy.

Posted By: Blakcharger440

Re: Damage to my Crane Rockers & Shafts (pics inside) - 10/04/09 10:29 PM

Quote:

Quote:

How do I make sure I am getting oil to the rocker shafts? Right now I have the intake and carb off.

Pull the distributor and drive gear and spin the oil pump with a priming tool.You'll need to rotate the engine at times in between.Or you can use a remote starter button and do it that way with out pulling the dizzy.

I have a remote starter so I will not have to remove the distributor.
How long should I crank the engine until I see some oil come up through into the heads?

Posted By: Anonymous

Post deleted by Defbob - 10/04/09 11:13 PM

Posted By: 9 Sec Phill

Re: Damage to my Crane Rockers & Shafts (pics inside) - 10/04/09 11:46 PM

Just a couple of questions,
#1 does the motor have head studs? If so im sure the the stud itself is to big(1/2") and cutting off oil flow to the rockers..DAMHIK..the stock bolt is under cut to give room for the oil to pass and get oil to the rockers. Running the stud cut oil flow almost 80% over the stock bolt.
#2 Did you have the shafts on the right way, there is a front and a rear for the oil holes to line up...
#3 Are the effected rockers from the front or rear of the motor?
#4 Nice looking place you got there

Posted By: Moparnut426

Re: Damage to my Crane Rockers & Shafts (pics inside) - 10/05/09 12:24 AM

I have seen the exact same result from good oil PSI, and everything good from using cranes shafts. They seem to chrome their shafts or something like that. In our dirt car running Brad penn oil, and 7200-8200 rpm all night long we say gaulding shafts. We finally spent the cash, bought the mopar performance bananna shafts, and the problem left. I just grooved the crane shafts just for one race to get us by until the shafts came in. I used a die grinder, and just made a slit on the preassure side of the shafts just like the mopar ones. I think the gaulding comes from the super hard chrome coatings, and the aluminum. Disimilar metals are the way to go, but when one is super hard plated, I think the chrome starts to flake starting a contact spot resulting in what you see there.

After I have used a non coated hard shaft I havent had any issues.

Hughes has some nice shafts also.

Kasey