Author Topic: Rocker arm adjuster wear.  (Read 1573 times)

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Jim Kramer

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Rocker arm adjuster wear.
« on: September 18, 2020, 09:27:46 AM »
I am seeing abnormal wear on the balls of my adjusters. I'm gaining considerable valve lash with only a few miles driving and it is coming from the adjuster balls that have worn as much as .030 in less than thirty miles. I replaced the original adjusters ( these arms are the low ratio Iskys ) with new Crane units but that didn't cure the problem. My push rods are 9.157 long Comp items, which are longer than stock, but are still below the spit hole in the rocker arm. The cups are still like new ( no wear ). No apparent wear on the rocker arms themselves, shafts, or anyplace else. The shafts are heavy wall aftermarket with a single oiling hole on the bottom and top of the shaft. Oil pressure is good with a minimum of 20 hot at 1000 rpm immediately rising as the speed increases to about 60 hot at maybe 2500. Valve springs measure about 300/310 at full lift ( about .520 ). I do have a restrictor in the heads, but it's .125 so shouldn't be the problem.

I've used this rocker arm assy. before on my 390 Stock Eliminator motor with no problem. The pushrods are new, with the extra length, to the equation. I'm wondering about the quality of the new Crane adjusters. Has anyone seen a problem with them?   Thank you......Jim Kramer

Drew Pojedinec

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Re: Rocker arm adjuster wear.
« Reply #1 on: September 18, 2020, 10:00:01 AM »
I am using crane adjusters on stock arms and have not noticed any issues.

cjshaker

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Re: Rocker arm adjuster wear.
« Reply #2 on: September 18, 2020, 10:46:30 AM »
If it happened with the old adjusters, I wouldn't blame the Crane units. Where is the wear on the balls taking place? Along the outside circumference, or in the middle area? Have you verified oil is getting to the rockers? Verified that the pushrod cup is the correct size for the adjusters? Too tight of a rocker/shaft clearance can stop oil flow enough that no oil will get to the areas that need to be fed, especially if there is no direct groove to the 'spit' hole for the pushrods.
Doug Smith


'69 R-code Mach 1, 427 MR, 2x4, Jerico, 4.30 Locker
'70 F-350 390
'55 Ford Customline 2dr
'37 Ford Coupe

Jim Kramer

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Re: Rocker arm adjuster wear.
« Reply #3 on: September 18, 2020, 11:24:57 AM »
CJ.. All your points are valid. The wear is occurring at the tip of the ball. In fact the pr. cup has a hole, ( not drilled through ), for pushrod oiling, and that has caused a pronounced "nipple" to be created on the adjuster ball. No visible evidence of oil starvation anywhere, even the ball itself doesn't "appear" to be staved of oil. I don't honestly know what the clearance might be between the arms and shaft, but the assembly isn't new, having seen hundreds of 7500+ quarter mile runs with no seen problems. I've thought too about cutting a groove in the rocker to promote pr. oiling. However every pushrod/adjuster lack of oiling problem I've envolves distressed looking components, but I'll admit I haven't come even close to seeing it all.    Thanks for your reply    Jim Kramer

Jim Kramer

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Re: Rocker arm adjuster wear.
« Reply #4 on: September 18, 2020, 11:29:38 AM »
Also to the question of sizing, good question, as there doesn't seem to be much info in the catalog listing as to sizing. Everything is listed as being 3/8. This is a possible issue........Jim Kramer

Rory428

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Re: Rocker arm adjuster wear.
« Reply #5 on: September 19, 2020, 02:37:32 AM »
What type of lifters are you running? All my flat tappet solid FEs have always used  around 9.35" length ball and cup pushrods. Are the balls burnt looking, or badly galled up? I have never had burnt up rocker adjuster balls or pushrods, using shaft oiling and restrictors much smaller than yours. If the rocker are not getting enough oil, I would look to make sure that you have the correct necked down rocker shaft bolts or studs, and see if the oil feed passage for the rockers is not partially blocked by the head gasket or cylinder heads if they are aftermarket. Also the rocker shaft holes should all be towards the bottom, if 2 holes, the second hole should face towards the pushrod side of the rocker arm.
1978 Fairmont,FE 427 with 428 crank, 4 speed Jerico best of 9.972@132.54MPH 1.29 60 foot
1985 Mustang HB 331 SB Ford, 4 speed Jerico, best of 10.29@128 MPH 1.40 60 foot.
1974 F350 race car hauler 390 NP435 4 speed
1959 Ford Meteor 2 dr sedan. 428 Cobra Jet, 4 speed Toploader. 12.54@ 108 MPH

Jim Kramer

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Re: Rocker arm adjuster wear.
« Reply #6 on: September 19, 2020, 09:47:47 AM »
That's the strange thing about this deal Rory, nothing shows any signs distress. the rocker arms are fine, as are the shafts, pushrods, and even the adjusters themselves "look" ok except for the wear. No bluing or galling. That's what led me to wonder about the hardness of the new adjusters I put in. The lifters are Crower "cool face" solids and the pushrods are Comp Cams 9.157. With the set-up I have they do put the cups pretty close to the bottom of the spit hole in the rocker arm. I don't remember who's shafts they were, ( I bought them 20 years ago ), but they have one hole on the top and one on the bottom, but again they have several hundred quarter mile runs on them with no problems. And I have studs, properly necked down.  Thanks......Jim Kramer