My 71 Duster work in progress

A fellow at FABO explained how to smash it with a hammer to restore the interference fit. That works for the time being anyway. If it works. It feels like it's harder to turn but who really knows. Only a road test will tell.
 
RUSTY Cuda said:
thread locker?
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The rockers are all adjusted now. Once I got started I just kept going. If I got that right with no noise after starting I will run it back and forth on a local highway that keeps me closer to home in case it backs out and starts making a racket again.

If it backs out again I'm going to red loctite it in place. It's either that or BOAT (Break Out Another Thousand) for rockers and pushrods.
 
The car didn't want to start so I started over and this time used orange lock-tite on the adjuster threads. Hoping for the best. The package called for 24 hours to set up.

It's hard to set the valves if the lifters have leaked off. Spinning the pushrod doesn't work, because there's no pressure holding the lifter against the pushrod, so I hold the rocker against the valve, then wiggle the pushrod around until the play is all gone. If you pay attention you can feel it after you can't see it anymore. That should be zero lash.
 
Redid the valves again, and this time I cleaned every adjuster and added orange lock-tite. I've never seen orange before but it said 3x stronger than blue right on the package and it doesn't require heat to remove it. I hope it works but am always skeptical.

Started her up and she tapped a little but I can work with that.

The big fan is a PITA. It has to come off to turn the engine over manually, and you have to turn the engine over manually to adjust the valves. I tried turning it with a remote starter but that's kind of impossible because you never get it to stop in the right place.
 
Work is in progress on a proper fix for the loose adjusters

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I didn't take a photo of the bolt/spacers/nuts that the rocker screws to
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Need to take some care to not grind too far away from the flat, but otherwise, just turn the lever and hold, lift to check.
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I put a box around it because it's making a mess.
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I tried to smooth it with the cookie but that thing gave up quick.
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To fix the top of the threads, chase the threads from the bottom.
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15 more to go.
 
I still don't think I've got the valves adjusted right but it's not overheating anymore. I drove the same route as took me to 230, this time it was shy of 190 all the time.

These danged lifters bleeding off is driving me nuts when I have to find zero lash. I know I've got way too much preload, but there's no valve noise now so I guess I went the right direction, just maybe too far.
 
I put the 650 double pumper on it but I'm just going to take it right back off again. I was hoping the engine would be "snappier" with a smaller double pumper on it, but it wasn't. The engine feels just as lazy off idle as it did with the 750 vac secondary brawler. Then as an added benefit it has a big sag once the secondaries open. I could tune that out if it would've helped with the lazy feeling, but it didn't so I'm not going to and am going straight back to the brawler.

Also to make you feel better @RUSTY Cuda the OP drops down to 20 at idle once I've driven it a while so the engine is truly at operating temperature.

Also too, I've got to adjust the valves One More Time because when the engine is hot and under load the valves float or at least I think that's what it is. I knew I didn't have them right but finally figured out my mistake so I can make it right now - if my inexperience hasn't already killed things LOL.
 
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Close but I'm closer to 10, but I think I have to raise the idle a bit, sure feels close to stall out to me, since it wasn't staling I left it alone, last time I raised it 1/4 turn, fine for a while & then took off & felt way too high.
It has a mind of its own!
 
I went back and readjusted the valves, zero lash then 3/4 turn for preload and it sounded like every lifter/rocker is tapping. Then I gave each one another 1/2 turn and it mostly quieted down but I'm back to what sounds like one clacking on each side and have no way to figure out which one.

I can keep adding preload to them but that's exactly how I ended up with a quiet valvetrain until the oil got hot enough for the valves to float from too much preload. I wish I knew what I was doing wrong.
 
I searched around today and found two methods to find zero lash, and I've tried them both. On one, you twirl the pushrod while tightening the adjuster until you feel it stop. On the other, you loosen the adjuster until you can feel the pushrod moving up and down, then tighten it until you can't feel it moving.

I tried both, followed by 3/4 turn of preload and in both cases I had clattering rockers. Then I added preload until the noise stopped, and then I had valve float.

The last time, I combined the two. Basically the pushrod wouldn't twirl about 1/4 turn after it stopped moving up and down. Then 3/4 turn of preload, and bang the same noisy valve train.

I'm using this to guide the order I work the valves

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RUSTY Cuda said:
Put on ear muffs!
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Yeah but if it's making noise it's beating something up.

I did some searching and found a 3rd method that I'd forgotten about. Jass and I had a conversation ^^ about it and he was against it, saying it would work on a GM engine but not a mopar due to the stud vs shaft rocker mounting differences. I remember being unconvinced but I just moved on to the 90* method from the MP decal.



Right now the valves are adjusted per "you twirl the pushrod while tightening the adjuster until you feel it stop". So, logic says, the pushrod would be tighter than that after turning in the preload, so it should be even harder to twirl it after adjustment.

I removed the valve cover on that side, and all the pushrods turned easily except two that were on the high side of the lobe.

That doesn't make much sense to me.

I think I'm going to back them all off and try the method from the video above. Here's the vice grip garage guy showing the same method.
 
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I've got adjustable hydraulic on my 440 and don't remember having trouble like this. It came with factory rockers and I woulda sworn I used this same chart when I installed the upgrade.

Note when the chart has #1 at TDC, you adjust #2I and #8E. While looking through youtube for info I saw more than one person say put #1 @ TDC (firing) and adjust both valves for #1, then rotate 90* and repeat for #8, etc.

One thing's for sure, I'm giving up on that chart.
 
I'm still having a helluva time with the valvetrain in this car. I went back over it again, then listened with a stethoscope to zero in on which rockers are raising Cain.

I'm down to one or the other of the valves on #7 cylinder. I was hearing a "sproing!" (not kidding) like I could hear the valve working. About a 1/4 turn tighter worked that out but now I've got one that clacks like you wouldn't believe through the stethoscope. The good thing, it's definitely the valve train and not something knocking in the bottom end. The bad thing is, well, I'll see if I can record it the next time I start it.

I plan to take the rockers off that side to see if there's any evidence of a rocker hitting the valve spring or a cracked rocker.
 
I got the valvetrain to shut up, now to find out if it's going to float the valves this time. That's not so much caused by too much preload as too much preload makes it more likely.

I was able to zero in on which valve was making noise by using a stethoscope.

I bumped the initial timing from 15 to 20 and limited that to 34 max. That fixed the sluggish throttle response. The last time I had it out I was getting kind of good at matching revs and that fixed a lot of the gear grinding downshifts - if I remember to do it.
 
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