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Rocker arm adjuster jam nut torque? #1374531 01/23/13 12:06 PM 01/23/13 12:06 PM
Joined: Aug 2005 Posts: 697 Central IL 70Sbird OP mopar
70Sbird OP mopar Joined: Aug 2005 Posts: 697 Central IL	Quick question, Got my pushrods last night for the 440 and am getting ready to install them and button things up. I have Stainless Steel roller rockers from PRW with a 7/16-20 adjuster screw and 12 point jam nut. Once I get the adjustment set how tight does the jam nut need to be? I called PRW's tech line and they told me 15-17 ft/lbs? That seems low to me, especially for a 7/16" fastner Any suggestions? Here is one of my rockers: Thanks Scott 7558366-Copyof2012-12-16rocker.jpg (738 downloads) Last edited by 70Sbird; 01/23/13 12:08 PM.

Re: Rocker arm adjuster jam nut torque? [Re: 70Sbird] #1374532 01/23/13 12:29 PM 01/23/13 12:29 PM
Joined: Mar 2007 Posts: 3,300 Northern Indiana Dunnuck Racing master
Dunnuck Racing master Joined: Mar 2007 Posts: 3,300 Northern Indiana	15 ft-lbs is plenty. You are not trying to stretch the adjuster like you would a fastener like a head bolt. The nut is only there to keep the adjuster from turning Its not as bad with steel rockers,but over tightening them on aluminum can damage the rocker's threads undertake jam nut. Keith www.dunnuckracing.com

Re: Rocker arm adjuster jam nut torque? [Re: 70Sbird] #1374533 01/23/13 12:50 PM 01/23/13 12:50 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	I dont know anyone that really torques them... I just give them a pull with your standard box wrench.. its maybe 20ft lbs(I use the wrench because I have the allen wrench in it to keep it in location)

Re: Rocker arm adjuster jam nut torque? [Re: MR_P_BODY] #1374534 01/23/13 12:57 PM 01/23/13 12:57 PM
Joined: Jan 2003 Posts: 9,876 Weddington, N.C. Streetwize master
Streetwize master Joined: Jan 2003 Posts: 9,876 Weddington, N.C.	I've gotten in the habit of checking them all with a torque wrench set at 18-20 lbs after running the valve lash. I do it pretty much just to make sure one of them wasn't left loose. I have had a threaded adjuster shear on the big end before, lash loosened way up but nothing catastrophic. Last edited by Streetwize; 01/23/13 12:59 PM. WIZE World's Quickest Diahatsu Rocky (??) 414" Stroker Small block Mopar Powered. 10.84 @ 123...and gettin' quicker! https://www.youtube.com/watch?v=-mWzLma3YGI In Car: https://www.youtube.com/watch?v=PjXcf95e6v0

Re: Rocker arm adjuster jam nut torque? [Re: Streetwize] #1374535 01/23/13 01:20 PM 01/23/13 01:20 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: I've gotten in the habit of checking them all with a torque wrench set at 18-20 lbs after running the valve lash. I do it pretty much just to make sure one of them wasn't left loose. I have had a threaded adjuster shear on the big end before, lash loosened way up but nothing catastrophic. I run down each side with the wrench before I throw the valve cover on... I did check the torque one time to see how close I was... its right around 20

Re: Rocker arm adjuster jam nut torque? [Re: Streetwize] #1374536 01/23/13 01:21 PM 01/23/13 01:21 PM
Joined: Jan 2003 Posts: 6,266 Renton Washington T Triple Threat master
Triple Threat master T Joined: Jan 2003 Posts: 6,266 Renton Washington	A bit spendy, but everyone I know who has one swears by it. http://lsmproducts.com/vlatw.htm -Dustin 67 Dart, 9 second, 392" G3 Hemi 68 Barracuda 340 F/SA

Re: Rocker arm adjuster jam nut torque? [Re: Triple Threat] #1374537 01/23/13 01:25 PM 01/23/13 01:25 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: A bit spendy, but everyone I know who has one swears by it. http://lsmproducts.com/vlatw.htm I have the non torque version of that

Re: Rocker arm adjuster jam nut torque? [Re: 70Sbird] #1374538 01/23/13 04:02 PM 01/23/13 04:02 PM
Joined: Nov 2008 Posts: 833 MN hemidup super stock
hemidup super stock Joined: Nov 2008 Posts: 833 MN	With PRW rockers I suggest using blue Loctite on the jam nuts. I've never had an issue with a jam nut loosening from any other brand. I've installed 3 sets of PRW rocker assemblies with the first 2 engines coming back with loosened jam nuts (don't know why?)and the adjusters almost backed out all the way. Leason learned, thus the blue Loctite. On the 3rd set I ordered the rockershafts were too large of diameter that the shim's wouldn't slide over the rockershaft. Again, leason learned. Also FWIW, the PRW rockershaft hold downs vary in width by up to .010" so I had to mark them idividually with a paint pen to keep them in the correct order during assembly. Was a real pain the first time I assembled the 1st set. They come at a great price, but I'm never using them again. As the old saying goes " The bitterness of poor quality remains long after the sweetness of low price is forgotten" Jerry Williams.

Re: Rocker arm adjuster jam nut torque? [Re: 70Sbird] #1374539 01/23/13 04:54 PM 01/23/13 04:54 PM
Joined: Aug 2005 Posts: 697 Central IL 70Sbird OP mopar
70Sbird OP mopar Joined: Aug 2005 Posts: 697 Central IL	Thanks for the feedback and tips everyone! I was just concerned about the low torque spec and remembered reading a thread a few weeks ago here on someones adjusters backing off or becoming loose but couldnt seem to find it again. This is a flat tappet hydraulic cam so once these are set, there shouldnt be much of a need to go back and reset the pre-load. I'll probably go with 20ft/lbs and a dab of blue Loctite!

Re: Rocker arm adjuster jam nut torque? [Re: MR_P_BODY] #1374540 01/23/13 04:57 PM 01/23/13 04:57 PM
Joined: Jul 2010 Posts: 3,502 SOUTH JERSEY HEMIFRED master
HEMIFRED master Joined: Jul 2010 Posts: 3,502 SOUTH JERSEY	Quote: I dont know anyone that really torques them... I just give them a pull with your standard box wrench.. its maybe 20ft lbs(I use the wrench because I have the allen wrench in it to keep it in location) for over 35 years I have used a small dead blow hammer and give the wench a light tap . home of the Sox and Martin Hemi Duster

Re: Rocker arm adjuster jam nut torque? [Re: HEMIFRED] #1374541 01/23/13 05:03 PM 01/23/13 05:03 PM
Joined: Oct 2005 Posts: 8,882 Ontario, Canada S Stanton Don't question me!
Stanton Don't question me! S Joined: Oct 2005 Posts: 8,882 Ontario, Canada	Quote: for over 35 years I have used a small dead blow hammer and give the wench a light tap . Every time I give my wench a light tap she threatens to call the cops - and I don't even use a hammer !!

Re: Rocker arm adjuster jam nut torque? [Re: Stanton] #1374542 01/23/13 05:25 PM 01/23/13 05:25 PM
Joined: Jan 2003 Posts: 9,876 Weddington, N.C. Streetwize master
Streetwize master Joined: Jan 2003 Posts: 9,876 Weddington, N.C.	WIZE World's Quickest Diahatsu Rocky (??) 414" Stroker Small block Mopar Powered. 10.84 @ 123...and gettin' quicker! https://www.youtube.com/watch?v=-mWzLma3YGI In Car: https://www.youtube.com/watch?v=PjXcf95e6v0

Re: Rocker arm adjuster jam nut torque? [Re: Streetwize] #1374543 01/23/13 06:22 PM 01/23/13 06:22 PM
Joined: Dec 2003 Posts: 901 oh julian2007 super stock
julian2007 super stock Joined: Dec 2003 Posts: 901 oh	if you want them to live,dont be a fool use a lsm tool. at least then you will never second guess your self. Most people who call them self a pro uses one. Im not a pro but I do what the pro's tell me to and my $hit lives a long time. I gave 170.00 for mine 7558776-lsmlashtool.jpg (428 downloads) Last edited by julian2007; 01/23/13 06:26 PM. God made cold beer,good friends,hot ladies and race cars don't spit in his face by pi$$ing and moaning about how life sucks!!!

Re: Rocker arm adjuster jam nut torque? [Re: 70Sbird] #1374544 01/23/13 06:31 PM 01/23/13 06:31 PM
Joined: Dec 2003 Posts: 901 oh julian2007 super stock
julian2007 super stock Joined: Dec 2003 Posts: 901 oh	Quote: Thanks for the feedback and tips everyone! I was just concerned about the low torque spec and remembered reading a thread a few weeks ago here on someones adjusters backing off or becoming loose but couldnt seem to find it again. This is a flat tappet hydraulic cam so once these are set, there shouldnt be much of a need to go back and reset the pre-load. I'll probably go with 20ft/lbs and a dab of blue Loctite! I have been racing for 20 years and never have had one back off yeat and never broke one.I always torque them and never use loctite. 7558785-SKINNY.jpg (236 downloads) God made cold beer,good friends,hot ladies and race cars don't spit in his face by pi$$ing and moaning about how life sucks!!!

Re: Rocker arm adjuster jam nut torque? [Re: Triple Threat] #1374545 01/23/13 06:49 PM 01/23/13 06:49 PM
Joined: Nov 2010 Posts: 1,397 Carson City, Nevada Biginchmopar pro stock
Biginchmopar pro stock Joined: Nov 2010 Posts: 1,397 Carson City, Nevada	Quote: A bit spendy, but everyone I know who has one swears by it. http://lsmproducts.com/vlatw.htm I have one and it is money well spent.

Re: Rocker arm adjuster jam nut torque? [Re: Biginchmopar] #1374546 01/23/13 07:49 PM 01/23/13 07:49 PM
Joined: Aug 2003 Posts: 1,062 Amherst,NY challengermike super stock
challengermike super stock Joined: Aug 2003 Posts: 1,062 Amherst,NY	I have had them back off 2 seperate times. Same prw rockers. But it looks like they changed the lock nut. It was a 6 point and now it looks to be a 12 point which are the same as the harland sharp ones i changed mine out to. You may not have to worry about it backing off. Mine took about 600 miles to start having the problem.

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