Burning up pushrods!

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SSG_Karg

SSG_Karg

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Ok guys, I’m at my wits end with this damn W2 motor. It is still cooking the pushrods at the rocker end. This has been a problem from the very beginning on this engine and I’m out of ideas on how to remedy this.
First I tried longer pushrods. Two sets actually. That made virtually no difference. So next I disassembled the rockers and shafts, blued the shaft, reassembled without the adjusters in and scribed the shaft where the oiling hole is in the rocker while the valve was on the seat. Then drilled the shafts on the scribe marks so all the oiling holes for the pushrods lined up perfectly. I then reassembled everything and primed the oiling system while the cam holes were lined up to get oil to that head and the oil was gushing out the holes around the adjusters. I say “gushes” because it flows steadily but does not squirt or shoot out in a stream.
Thought that would surely solve my problem but less than 100 miles later I started to hear a clatter under the valve cover. Pulled the cover and found the #1 exhaust rocker adjuster ball was half eaten away and the pushrod was badly discolored from overheating.
So now I’ve tried 3 different sets of Smith brothers pushrods, fixed the oiling holes, and I have metal in the motor from a smoked adjuster ball.

This is a stroked smallblock with a solid roller. Just a shade under 500# over the nose, so stout but nothing radical.
WTF IS GOING ON????

Is it possible that the cup on the pushrod is not “open” enough to receive the oil that is running down the adjuster and it can’t get into the cup? It looks like a snug fit. I told Smith Brothers what diameter my adjusters are and ordered the corresponding cup size.

Any suggestions would be appreciated because I’m about ready to shitcan these W2s.
Thanks

IMG_6640.jpeg


IMG_6639.jpeg


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IMG_6635.jpeg
 
Looks like no oil up to the shafts. Pull them and prime the oil pump and watch for oil coming up through a couple stands. Those shafts gave to go on just so to get oil. Watching the game. No time to be specific.
 
in the last picture posted, are there holes in the "flat" area where oil would spray on the pushrod end?
another idea would be AMC lifters with hollow pushrods?
 
Best I can figure is that the pushrods are too long! There's suppose to be a thread or two of the adjuster showing below the rocker. With the pushrod cup too close to the bottom of the rocker, the "squirt" from the hole in the rocker is squirting too much oil below the cup instead of onto/into the cup.

Also, check if there is any sign of any pushrod cup "rims" contacting the underside of the rockers.

Either way, shorter pushrods will put the parts in a better relationship to each other.


EDIT - once you figure the optimum length and wanna be nit-picky, the intake pushrods should be a bit longer than the exhausts because of the angle of the intake. I think I came up with +.020, but that was many moons ago and I don't quite remember exactly.
 
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Locomotion said:
Best I can figure is that the pushrods are too long! There's suppose to be a thread or two of the adjuster showing below the rocker. With the pushrod cup too close to the bottom of the rocker, the "squirt" from the hole in the rocker is squirting too much oil below the cup instead of onto/into the cup.

Also, check if there is any sign of any pushrod cup "rims" contacting the underside of the rockers.

Either way, shorter pushrods will put the parts in a better relationship to each other.
Click to expand...
The first set of pushrods I had in there were .150” shorter, which put about 2-3 threads below the rocker. Same results-blue cups. Cups have plenty of clearance to the back of the rocker and are not contacting the heads anywhere.

First set of rods…..

IMG_6641.jpeg


IMG_6642.jpeg
 

SSG_Karg said:
The first set of pushrods I had in there were .150” shorter, which put about 2-3 threads below the rocker. Same results-blue cups. Cups have plenty of clearance to the back of the rocker and are not contacting the heads anywhere.

First set of rods…..

View attachment 1716408672

View attachment 1716408673
Click to expand...


What is your hot oil pressure at idle?

If it’s less than 40 on the gauge you won’t have enough oil there at idle.

Also, I’d be looking at an oil that is an actual 100% Group IV/V base oil and has an additive package that uses oil soluble moly.

That will help.
 
RustyRatRod said:
They should already be I thought.
Click to expand...


That’s what I was saying. To put the oil hole in the rocker where Chrysler put it makes it so the rocker isn’t thick enough to be drilled to use that style of adjuster.

BUT, if the rocker would take it Thats the adjuster that should be used.
 
Seeing as it’s got a roller cam, could you possibly need slightly more clearance at the pushrod cup end to account for the rods & lifters not turning? In turn, providing more oil to the pushrod cup?
 
Newbomb Turk said:
That’s what I was saying. To put the oil hole in the rocker where Chrysler put it makes it so the rocker isn’t thick enough to be drilled to use that style of adjuster.

BUT, if the rocker would take it Thats the adjuster that should be used.
Click to expand...
I'm not understanding. If the rocker is drilled...and I think they are, how could the oil through adjusters not work? They are made with a machined trough all the way around so the oil can flow. I've had many sets of those rockers and I thought they were drilled like that. Heck, all my slant 6 rockers ARE.
 
RustyRatRod said:
I'm not understanding. If the rocker is drilled...and I think they are, how could the oil through adjusters not work? They are made with a machined trough all the way around so the oil can flow. I've had many sets of those rockers and I thought they were drilled like that. Heck, all my slant 6 rockers ARE.
Click to expand...


If you look at the Manton adjuster, you see the oil groove around it. That groove has to be up in the rocker. To get it far enough up in the rocker the tip of the adjuster will be in the rocker.

Almost any rocker that has Chrysler oiling in it can’t use that adjuster.
 
Newbomb Turk said:
If you look at the Manton adjuster, you see the oil groove around it. That groove has to be up in the rocker. To get it far enough up in the rocker the tip of the adjuster will be in the rocker.

Almost any rocker that has Chrysler oiling in it can’t use that adjuster.
Click to expand...
Those are all examples. They'll put the oiling groove anywhere you want it.
 
SSG_Karg said:
The first set of pushrods I had in there were .150” shorter, which put about 2-3 threads below the rocker. Same results-blue cups. Cups have plenty of clearance to the back of the rocker and are not contacting the heads anywhere.

First set of rods…..

View attachment 1716408672

View attachment 1716408673
Click to expand...
A .150" difference is a big jump! In the first pic, the intake pushrod (right side) is definitely way too short. The exhaust pushrod (left side) could be a bit longer. My earlier guesstimate of .020" being the difference needed between intake & exhaust length pushrods is obviously too small. (It looks like the intake pushrod is turning color while the exhaust isn't!)

FWIW, the Mopar Race Manuals which I followed since I started racing call for 0-1 threads showing!

Pattern? - Were the same pushrods getting burned up when using all longer and all shorter pushrods? Otherwise, if more exhausts were burning up when using longer pushrods, that may indicate they were too long. If more intakes were getting burned up when using shorter pushrods, that may indicate they were too short.

If we can agree on the interpretation of 0-1 threads showing, then you can determine the proper pushrod length using a known length pushrod for the test.

Set it all up for "0" lash using a known pushrod length. Determine how many thousandths each full adjuster turn is based on thread count per inch of the adjuster. Turn the adjuster in or out to get 0-1 thread showing. Multiply that # of turns by the distance each thread is equal to, minus the lash you use. Add or subtract that final number from the pushrod length you're using gets you the needed pushrod length - intake and exhaust. (At least that's the way I've done it for solid lifters.)

I'm not saying I'm right, but it seems that all other possibilities were checked....except.....I don't know how or if it could affect the pushrod oiling in any way, but the only other thing I can think of is the height or offset of the rocker assembly using the blocks. It was a steep learning curve when I first got into W-2 stuff but that was over 40 years ago an got away from it in 1999.

No pushrod contact anywhere through the range in the pushrod tunnel in the head?

Regardless of who's right or wrong, I hope you find the problem soon.
 
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Can you remove an adjuster & take a pic so we can see any holes/grooves in it?
 
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