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#2562632 - 10/11/18 08:19 PM What could cause lash to open?
1mean340 Offline
enthusiast

Registered: 10/09/08
Posts: 334
Loc: Suffolk County, New York
Hey guys, adjust the lash cold according to the cam card on my 340 with w2 econo heads, keen engineering shaft mounted rockers and a solid roller cam (.609 lift).

Been having a lot of tuning problems with the EFI setup trying to get it right with e85 and boost, plugs have been looking very inconsistent with the single plane but compression tests always show within 5 psi on every cylinder whenever I check. Can't get a clean pass, but I am assuming it is EFI related.

Anyway, after adjusting the lash everything was quiet, I was actually making progress with the tune but then after maybe 200 miles or so it started running like crap. I noticed a lot of rocker arm noise from the passenger side which also happens to be the wideband 02 bank the fitech EFI uses to adjust AFR.

A few of the intake rockers I checked were up to around 25 thousandths (they were all set at 16). Oddly enough, all the rockers on the driver's side are within 1 or 2 thousandths of where I set them.

So what would cause lash to open up so much after only 200 miles? Keep in mind I have a soft touch rev limited set at 6400, I've been shifting around 6k or less. I've been beating on it trying to tune but it hasn't really seen any serious abuse/high revs/full passes.

Also, do you guys think the lash open that far could actually be causing some of the tuning issues with the EFI (stalling at idle, feeling flat)? I ask because I thought I was making improvements with the tune but it started running worse and worse a little before I noticed the excessive rocker noise.



Edited by 1mean340 (10/11/18 08:25 PM)
_________________________
B5 '70 Challenger. 340/727A. Forged 340, ported W2 econos, .609/.609, 242/246 112LSA SR, FITECH 1200, home built D1SC procharger setup, E85. Still working on FITECH tuning bugs/procharger tensioner and alignment issues.


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#2562633 - 10/11/18 08:27 PM Re: What could cause lash to open? [Re: 1mean340]
fast68plymouth Offline
I Live Here

Registered: 01/20/03
Posts: 11485
Loc: So. Burlington, Vt.
Loosening lash is never good.

Worn adjuster screw, pushrod, cam, lifters........ or a bent valve.

I’d start by doing a leak down test of the cyls with the loose lash.
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68 Plymouth Satellite, 383, stock 906's, 3550lbs, 11.18 @ 123, 1.51 60'
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#2562635 - 10/11/18 08:31 PM Re: What could cause lash to open? [Re: 1mean340]
madscientist Offline


Registered: 09/17/14
Posts: 2485
Loc: Washington
I've never heard of the Keen rockers and shafts?

Any info on them?
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Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston

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#2562636 - 10/11/18 08:32 PM Re: What could cause lash to open? [Re: 1mean340]
fourgearsavoy Offline


Registered: 12/07/04
Posts: 9337
Loc: Rittman Ohio
Mine is most likely a solid flat tappet cam going round. But I have the same issue,.028 on #4 and #6 and I set them at .016 in the spring.

I doubt that a solid roller cam is worn out though maybe a bent pushrod shruggy

Gus beer
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#2562646 - 10/11/18 08:55 PM Re: What could cause lash to open? [Re: 1mean340]
justinp61 Offline
master

Registered: 10/01/03
Posts: 9767
Loc: W. Kentucky
Are you positive you have the rocker arm shaft oriented right? How do the rocker ends of the push rods, adjusters look?

I can tell you from first hand experience if you install the shaft wrong the lash will open up. It will also burn up the adjusters and push rod tips.

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#2562648 - 10/11/18 08:56 PM Re: What could cause lash to open? [Re: 1mean340]
Cab_Burge Offline
I Win

Registered: 08/23/03
Posts: 31704
Loc: Bend,OR USA
Take a hard look at the top of the valve train parts as they are now, adjusters and pushrods, check the torque on the shafts and go from there scope
If you don't find anything up there remove the oil filter and cut it open and look real hard between the pleats for small debris, hopefully you won't find any cam and lifter debris luck scope
Please let us know what you find up
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Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

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#2562652 - 10/11/18 09:06 PM Re: What could cause lash to open? [Re: 1mean340]
1mean340 Offline
enthusiast

Registered: 10/09/08
Posts: 334
Loc: Suffolk County, New York
Fast 68, definitely wanted to do a leak down anyway because of the pretty big inconsistencies I am seeing in the plugs. I'll give that a shot.

Motor is brand new, didn't see anything unusual as far as metal in the last oil change but I never cut the filter open.

Mad scientist, they are stamped keen engineering but also have a mopar performance stamp on them. I am guessing it was a company that made rockers for mopar performance? They are blue anodized needle bearing rockers.

I'll check the pushrod ends at the rocker but I didn't notice anything unusual when I checked the lash. The pushrod angles are pretty bad and I was planning on purchasing a shim kit for better geometry but the way it is now was run on another LA motor and never had any issues running 9's, so I figured it would be OK for a while just till I sort other bugs out.

Justin, what do you mean by oriented right?

Ps as far as the stalling/running crappy thing, don't put too much weight in that being pushrod related because this fitech has been nothing but trouble with e85...i wouldn't put that past being just fitech related but it just seemed coincidental that the "tuning"'problems seem to get worse and then i noticed the noise.


Edited by 1mean340 (10/11/18 09:08 PM)
_________________________
B5 '70 Challenger. 340/727A. Forged 340, ported W2 econos, .609/.609, 242/246 112LSA SR, FITECH 1200, home built D1SC procharger setup, E85. Still working on FITECH tuning bugs/procharger tensioner and alignment issues.


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#2562657 - 10/11/18 09:15 PM Re: What could cause lash to open? [Re: Cab_Burge]
1mean340 Offline
enthusiast

Registered: 10/09/08
Posts: 334
Loc: Suffolk County, New York
Can, will do! I have never gotten this setup work right, but I have gotten it to give me intermittent bursts of awesomeness power. What concerns me is when I first started working with the EFI setup there would be times on boost where it would blow the drag radials off and felt every bit of a 550+hp car, then other times it would pull like dog poop. That was reflected in the AFR's though in logs with the fitech swinging like a pendulum.

What worries me now is I have worked out some of the issues with the fitech 'chasing its tail' and the last few times I've romped on it , it nailed the AFR's under boost, yet it pulled like garbage. It revved out clean, but had no power. That kinda scares me.


Should have done a leak down a long time ago, and really hoping I don't find deposits from my lifters in the filter lol. That would impressive carnage, even for me, being it's roller lifters
_________________________
B5 '70 Challenger. 340/727A. Forged 340, ported W2 econos, .609/.609, 242/246 112LSA SR, FITECH 1200, home built D1SC procharger setup, E85. Still working on FITECH tuning bugs/procharger tensioner and alignment issues.


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#2562661 - 10/11/18 09:23 PM Re: What could cause lash to open? [Re: 1mean340]
justinp61 Offline
master

Registered: 10/01/03
Posts: 9767
Loc: W. Kentucky
This a stamped adjustable rocker with a roller cam? Never heard of them.

The rocker shafts only go on one way, if you put them on backwards they won't oil right.

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#2562664 - 10/11/18 09:24 PM Re: What could cause lash to open? [Re: 1mean340]
Cab_Burge Offline
I Win

Registered: 08/23/03
Posts: 31704
Loc: Bend,OR USA
I didn't realized it was a roller cam motor blush If it is eating a lobe it will have big chunks in the filter, it is a bad roller wheel it would have had a lot more valve to pushrod clearance now work
I did a W2 N/A pump gas street motor years ago for 9secondphil, it had a custom ground comp Cams solid flat tappet cam in it with a little over 430 Lbs. opened and around 170 lbs. on the seats, he drove it around 20,000 miles and then the top of the lifter cups started flaking apart sending debris down onto the piston skirts eating them up and the cylinder walls whiney shruggy
BTW, did you set your motor up to oil the rockers full time? If not you should up twocents That really helps keep the valve spring cool, some guys say that makes the oil temps go up quicker so it must be sucking heat out of the valve springs, huh work up
_________________________
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

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#2562768 - 10/12/18 02:22 AM Re: What could cause lash to open? [Re: Cab_Burge]
sasquatch Offline
top fuel

Registered: 03/26/05
Posts: 2298
Loc: North Carolina
With it being a W2 motor check that the pushrods are not rubbing. It can cause all sorts of valve train gyrations.
todd
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#2562805 - 10/12/18 08:57 AM Re: What could cause lash to open? [Re: justinp61]
FurryStump Offline
master

Registered: 10/15/04
Posts: 2564
Loc: Connecticut
Originally Posted By justinp61
This a stamped adjustable rocker with a roller cam? Never heard of them.

The rocker shafts only go on one way, if you put them on backwards they won't oil right.
i read it that way at first. I believe it is an aluminum rocker “stamped” with the name of the manufacturer.
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#2563807 - 10/14/18 10:12 AM Re: What could cause lash to open? [Re: 1mean340]
justinp61 Offline
master

Registered: 10/01/03
Posts: 9767
Loc: W. Kentucky
Any updates?

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#2563854 - 10/14/18 12:03 PM Re: What could cause lash to open? [Re: 1mean340]
1mean340 Offline
enthusiast

Registered: 10/09/08
Posts: 334
Loc: Suffolk County, New York
Hey guys, I haven't had a lot of time but I was able to go over the driver's side bank yesterday (decided to just go side to side instead of by firing order because I suspected the lash only opened up on P side rockers).

Sure enough, almost all the rockers on the driver's side were still good, within 1 or 2 thousandths of where I lashed them last.

I only got to cylinder 2 on the passenger side and the lash was opened by about 6 thousandths from where I set them last. I notice the adjuster nut seemed easier to break loose than the others (I torque them all with a torque wrench to 20ft lbs when I do them) but it was still fairly tight. I didn't note anything on the adjuster, I mean they are used adjusters and I can see a little light scuff on the ball but nothing glaringly obvious, no sign of heat or anything like that. Rocker end of the pushrod looked OK too.

Shafts hold downs were tight.

Spinning the motor over by hand it spins completely freely (almost spins too freely if that is possible lol) and I don't hear any strange noises or grinding coming from anywhere in the lifter area.

I'll check the rest today and will also try to get to the leak down test. anything else I should look for?


Edited by 1mean340 (10/14/18 12:13 PM)
_________________________
B5 '70 Challenger. 340/727A. Forged 340, ported W2 econos, .609/.609, 242/246 112LSA SR, FITECH 1200, home built D1SC procharger setup, E85. Still working on FITECH tuning bugs/procharger tensioner and alignment issues.


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#2563856 - 10/14/18 12:09 PM Re: What could cause lash to open? [Re: 1mean340]
1mean340 Offline
enthusiast

Registered: 10/09/08
Posts: 334
Loc: Suffolk County, New York
Oh, and yes they are aluminum rocker arms
IMG_4490 by Kris A, on Flickr

the heads were clearance already for the pushrods from the last motor they were on (they belonged to a forum member) but my machinist double checked and took away a little more where he thought it needed it. I don't see any sign of the pushrods touching anywhere and don't hear anything when turning the motor over by hand.

I shimmed them all so there is less than 20 thousandths of side to side play although even a TINY bit of side play still seems to change the lash, but only by 1 thousandth or so.

One thing that worried me is when checking the lash, there seems to be enough side load that I have to pry the rockers apart before checking lash or else they are 'stuck' pushed against the side of the shaft block or the other rocker and you can't wiggle it for lash. I was worried that could be a problem, but it didn't seem to affect anything on the driver's side so I don't know why it would on the passenger side.

I know this valve train sucks and I desperately need a spacer kit to fix crazy pushrod angle a bit but just wanted to get it all working for now to get the car drivable with the fuel injection system. When I start racing it more I plan on doing something about it. My machinist is a mopar guy (Lawrence Racing Engines) and he said it could be better but he has also run worse with no issues.


Edited by 1mean340 (10/14/18 12:17 PM)
_________________________
B5 '70 Challenger. 340/727A. Forged 340, ported W2 econos, .609/.609, 242/246 112LSA SR, FITECH 1200, home built D1SC procharger setup, E85. Still working on FITECH tuning bugs/procharger tensioner and alignment issues.


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#2563869 - 10/14/18 12:38 PM Re: What could cause lash to open? [Re: 1mean340]
madscientist Offline


Registered: 09/17/14
Posts: 2485
Loc: Washington
If the lash is moving around and the adjusters are coming loose it's a sign the pushrods are flexing.

You should at the minimum be using 7/16-3/8 single taper pushrods. I fought that same issue. If the lash is moving and the adjusters are staying tight it's another issue.
_________________________
Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston

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#2563986 - 10/14/18 04:16 PM Re: What could cause lash to open? [Re: 1mean340]
Twostick Offline
master

Registered: 05/20/03
Posts: 5122
Loc: Downtown Roebuck Ont
Check the axles on the roller tips. I had a set of knock off Comp magnums and the roller tips were all rattling on the axles.

Kevin

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#2564048 - 10/14/18 06:46 PM Re: What could cause lash to open? [Re: 1mean340]
DrCharles Offline
master

Registered: 04/12/06
Posts: 3381
Loc: West Plains, MO
Lots of possibilities, but why only on the passenger-side bank? shruggy

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#2564414 - 10/15/18 12:41 PM Re: What could cause lash to open? [Re: 1mean340]
540DUSTER Offline
mopar

Registered: 12/27/03
Posts: 523
Loc: USA
It looks like to me that the first rocker on the left in your pic the adjuster screw is a lot deeper in the rocker than the others.Why? Also the push rods look to be short.What is the distance between the bottom of the rocker and the end of the adjuster screw?What is the radius of the adjuster ball and the radius of the push-rod cup? The mopar bible says to set adjusters to 5/16" below the rocker.Not all adjusters are the same,the distance from the end of the adjuster and where the threads start are different between companies.I never count how many threads are showing below the rocker.Good luck with it.

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#2564810 - 10/16/18 11:29 AM Re: What could cause lash to open? [Re: 1mean340]
1mean340 Offline
enthusiast

Registered: 10/09/08
Posts: 334
Loc: Suffolk County, New York
Sorry to keep only reporting back with bits and pieces, just been really short on time lately.

I should be able to get around to checking all the lash on the 'bad' side today and also check the roller tips too. The pushrods flexing sounds plausible too, but like Madscientist said, why it would only happen on one bank beats the hell out of me.

I did get a chance to cut the filter open. Please excuse it being mangled, ran out of die grinder wheels, couldn't find my tin snips and thought using an air chisel would be a good idea LOL.

The oil that came out of the filter was a bit gray but didn't really have any metal sheen to it when rubbing it between the fingers. I couldn't find any metal dust, flakes or anything in the filter upon inspection. I even blew it out with brake cleaner into a clear plastic pan and there was nothing (the metal flakes towards the top of the pan there I believe are from the filter and my air chisel job, you can see the orange paint on them).

Keep in mind, this oil probably has less than 500 miles on it, not sure exactly since I still haven't had a chance to order a new speedo gear. The motor itself probably has under 2k miles on it.

When I did the first oil change after break in there was a tiny amount of metal dust on the magnetic drain plug but didn't look excessive for a new motor. I never checked the filter, probably should have.

540 duster, I noticed a difference on a few even the last time I adjusted it with the adjuster being at different heights after setting lash. I notice one on the "good" side where I couldn't get a shallow socket on to do my final torque check whereas all the others I could. I'm thinking I might buy all new adjusters for the hell of it. One was frozen up pretty bad as well.


Attachments
IMG_6384.JPG

IMG_6387.JPG




Edited by 1mean340 (10/16/18 11:35 AM)
_________________________
B5 '70 Challenger. 340/727A. Forged 340, ported W2 econos, .609/.609, 242/246 112LSA SR, FITECH 1200, home built D1SC procharger setup, E85. Still working on FITECH tuning bugs/procharger tensioner and alignment issues.


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