340 adjustable LOCKING rocker arm kit

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pauls340

pauls340

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I actually only need the threaded adjusters with lock nuts for a stock 1970-71 340. I've checked many places only with a NO, don't have: Bouchillon, Jegs, Summitt, Mancini, Hughes. This is a pic of the first two bent CompCam pushrods. The adjustable rocker arm set is for the 273 engine and everything was new. Nobody had LOCKING adj rockers at the time so we went with these. 30 minute run time and the first 10 mile round trip and BAM! Can anyone help? Thanks

Rocker bent.jpg
 
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pauls340 said:
I actually only need the threaded adjuster with lock nut for a stock 1970-71 340. I've checked many places only with a NO, don't have: Bouchillon, Jegs, Summitt, Mancini, Hughes. Can anyone help? Thanks
Click to expand...
The Chrysler rocker arm on the 273 and the 70 340, 6 pack do not have a lock nut they have a varying thread that causes the tension between the adjuster and the rocker arm that holds the adjuster in place when you adjust it. Now the thing that you do is you tap those rocker arms out to straighten those threads out and you put in the ones that use the nuts to lock them down. But you also want to take a flat file and dress the top of that area on the rocker arm where that nut sits otherwise it's going to back itself off. Here is the kit from jegs.

PRW 1203188 Rocker Arm Valve Lash Adjuster Screw Kit Mopar 273-440 4135 Alloy St | eBay
 
You want to make sure the thread size matches the factory rockers. For whatever reason ones to fit stock rockers (but tapped) are hard to find.
Jadaharabi said:
The Chrysler rocker arm on the 273 and the 70 340, 6 pack do not have a lock nut they have a varying thread that causes the tension between the adjuster and the rocker arm that holds the adjuster in place when you adjust it. Now the thing that you do is you tap those rocker arms out to straighten those threads out and you put in the ones that use the nuts to lock them down. But you also want to take a flat file and dress the top of that area on the rocker arm where that nut sits otherwise it's going to back itself off. Here is the kit from jegs.

PRW 1203188 Rocker Arm Valve Lash Adjuster Screw Kit Mopar 273-440 4135 Alloy St | eBay
Click to expand...
 
4spdragtop said:
You want to make sure the thread size matches the factory rockers. For whatever reason ones to fit stock rockers (but tapped) are hard to find.
Click to expand...
Not only check the diameter of the adjuster but you also want to make sure that the ball is the correct one for the end of your push rods.
 
Jadaharabi said:
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Yours are the same part number and the same price as the one that I posted in number two post. The only difference is the Jegs is on eBay and in your case it's on Amazon.
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Even Summit has them shown. Says they'll drop ship from PRW tomorrow. So they're not unobtainium.
 
Napa has them listed for the 273 interference fit. Post a photo or two of your rockers. They may be a Crane or Isky that have a machined area for the lock nut. The stock ones didn't. https://www.napaonline.com/en/p/SEPMR1933?impressionRank=1 Summit has them listed as well. Sealed Power MR1933
pauls340 said:
I actually only need the threaded adjuster with lock nut for a stock 1970-71 340. I've checked many places only with a NO, don't have: Bouchillon, Jegs, Summitt, Mancini, Hughes. Can anyone help? Thanks
Click to expand...

upload_2022-7-11_12-51-27.png
 
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Whe I click Amazon link I get "currently unavailable " must be cuz I'm in Canada?
I see nothing that gives thread size?

Jadaharabi said:
The Chrysler rocker arm on the 273 and the 70 340, 6 pack do not have a lock nut they have a varying thread that causes the tension between the adjuster and the rocker arm that holds the adjuster in place when you adjust it. Now the thing that you do is you tap those rocker arms out to straighten those threads out and you put in the ones that use the nuts to lock them down. But you also want to take a flat file and dress the top of that area on the rocker arm where that nut sits otherwise it's going to back itself off. Here is the kit from jegs.

PRW 1203188 Rocker Arm Valve Lash Adjuster Screw Kit Mopar 273-440 4135 Alloy St | eBay
Click to expand...

RustyRatRod said:
Amazon. In stock.
https://www.amazon.com/dp/B007KXLDOC/?tag=fabo03-20
Click to expand...

RustyRatRod said:
See post #5. In stock.
Click to expand...
 
The problem is, PRW shows TWO different part numbers. One is clearly advertised as 7/16 the other is not so clear. There's no reason for two different part numbers in the same size, so it's gotta be a typo. One is 3/8 and the other is 7/16. You're probably gonna have to call someone at PRW that will actually WALK out in the warehouse and LOOK at the part.
 
RustyRatRod said:
The problem is, PRW shows TWO different part numbers. One is clearly advertised as 7/16 the other is not so clear. There's no reason for two different part numbers in the same size, so it's gotta be a typo. One is 3/8 and the other is 7/16. You're probably gonna have to call someone at PRW that will actually WALK out in the warehouse and LOOK at the part.
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7/16 is a big block Chevy size.
 
4spdragtop said:
Whe I click Amazon link I get "currently unavailable " must be cuz I'm in Canada?
I see nothing that gives thread size?
Click to expand...
Right, it is confusing on the thread size and I would VERIFY first, but surely one is 3/8 and the other is 7/16. What sense would it make to make two sets of 7/16 with different part numbers?
 
Hell, if nothing else, drill and tap the rockers to 7/16 20 and put the larger screw in. There's plenty of meat to do it.
 
pauls340 said:
I actually only need the threaded adjuster with lock nut for a stock 1970-71 340. I've checked many places only with a NO, don't have: Bouchillon, Jegs, Summitt, Mancini, Hughes. Can anyone help? Thanks
Click to expand...
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Well I thought you were being help but evidently somebody thought you weren't and eliminated all of the postings. What's the sense of helping somebody if they're just going to be deleted kiss my butt whoever did that.

Having said that I think that toolmanmike made things right so he doesn't need to kiss my butt. LOL
 
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