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By charliemccraney - 17 Years Ago
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The pushrod cup is wearing for some reason. They're all rotating and I measured the lobe lift at .288 which is very close to the .295 that is stated on the cam card. Figure in a little sine error and it's probably right on. Does this indicate that the Y also has excellent geometry? I've watched Don assemble several chrysler small blocks. The geometry is so horrible that the actual lift that can be achieved tends to be around 95% of advertised. It doesn't sound like much but thats about .030" on a .500" lift cam. Of course, these measurements are at the valve. 
I'm exhausted and haven't yet checked out the adjuster screw for burrs that may be doing this. I'll just say that I'm a happy camper. It'll be a cheap and easy fix. To bad this kept the truck from making an appearance.
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By Hoosier Hurricane - 17 Years Ago
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Charlie: Check the rocker arm, there is a small hole just behind the adjuster screw that dribbles oil on the pushrod. Someone just found some rockers with those holes plugged with setscrews. That's odd, but his set weren't all plugged, so there may be a few more of those floating around. They can also be plugged with sludge that doesn't get cleaned out when the parts are tanked. Good to meet you last weekend, sorry you had to take the truck back home. Really made your trip a lot longer, you looked tired. John
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By charliemccraney - 17 Years Ago
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I'll certainly take a look at the oil holes. I have the Dove roller rockers. Maybe there's a chunk of aluminum in there. I've seen that on other parts before. I am glad to have met you and everyone else. It's good to know who I am talking to. You just can't find out who someone is on a forum. I was tired. Still am. I was expecting to arrive around 7:00pm Friday rather than 5:00am on Saturday.
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By PF Arcand - 17 Years Ago
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Charlie: Did you happen by chance to have bought that pushrod in recent times? There was an article in Y-Blk Mag recently (issue #79 or #80 I think?) by J. Mummert, that some inferior pushrods (read made overseas!) have surfaced recently. Apparently the radius is wrong at the cup where it fits against the rocker arm.
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By pegleg - 17 Years Ago
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Charlie, From the picture, the thing looks just plain soft. Like it was never heat treated. Excessive clearance would have aggravated the situation. Dove hasreportedly had quality issues in the past, so do as John said and check for oiling passages. Better this than a cam lobe or lifter though!
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By Ted - 17 Years Ago
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Charlie. Add this to the list of things to look at. There’s a slim chance that the oil groove in one or more of the Dove rockers is not aligning with the lower oil hole in the shaft. This becomes more pronouced as the rockers are shimmed to better center or locate the rockers either on the valve tip or the pushrod holes. I typically remedy the oil hole misalignment by just grinding an angled slot about a ¼” long across each shaft oil hole to insure that oil gets to the rocker as designed. 
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By charliemccraney - 17 Years Ago
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The pushrods were used on the old engine as well. They were on there for 10k miles. I had stock high ratio rockers on the new build for about 30 miles They weren't staying adjusted - the screws were backing out. The Dove rockers were installed at that time. I'll check the alignment of the oil holes as well.
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By aussiebill - 17 Years Ago
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Charlie, teds right on the money with the oil hole alignment. i,ve been running dove aluminum rockers for years, and found several dont get oil through them and hence dry pushrod cups, his mod fixes this. Aussiebill..
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By charliemccraney - 17 Years Ago
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Thanks Ted. I have modified the rocker shaft. All of the oiling holes in the rocker arms are obstruction free. Have you had any of these rocker arms with bad screws? The screw that corresponds with the bad pushrod is not breaking in like the others. All of the other pushrods look ok. The bad one: The camera makes it look shinier than it is. It hardly looks like it's been installed. I didn't spot any wear pattern anywhere along the ball. 
The rest have a similar polished pattern such as: 
I'm also curious as to what formed the step in the pushrod in the first picture I posted. I can't find anything to explain that.
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By Pete 55Tbird - 17 Years Ago
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Wild guess as to why it is not shiny. Is the lifter rotating?
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By pegleg - 17 Years Ago
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Charlie, Looks like a mismatch in the radii. How well do they fit together. Maybe try it with a good pushrod or check the ball sizes versus one that's working correctly. The oil situation wouldn't help, either.
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By Ted - 17 Years Ago
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Besides the other comments regarding the wear pattern, I’m thinking that the pushrod cup wore so quickly that it wasn’t hard enough to leave a wear pattern on the rocker stud. Only bad screw I’ve seen in the past was one where the hex for the allen wrench wasn’t broached in the top side of the stud and was just a round hole but the screw was otherwise okay.
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By charliemccraney - 17 Years Ago
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Do you think it will be a good idea to use one of the old push rods in this same location so that I don't risk sacrificing one of the new ones - only to make sure the problem is solved. Lack of oiling as a result of an insuficient supply from the shaft isn't satisfying me. #5 exhaust isn't shimmed and the hole appears to be in the correct position to line up with the groove. Others had worse alignment with the hole, without worn pushrods. I ordered replacement pushrods from John Mummert. He said that he had sold shorter pushrods for the Dove rockers. He had none in stock though. I remember the instructions of some aftermarket roller rockers for a Chrysler emphasized a minimum distance between the pushrod and rocker for oiling purposes. I wonder if this may be occuring on my #5E rocker for some reason. Perhaps the hardened part of the pushrod got worn through?
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By Ted - 17 Years Ago
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Charlie. Using one of the original pushrods in lieu of a new one sounds like a good idea to verify if the 'wear' problem has gone away. I'm hoping you just had a soft pushrod at this point. Just double check the radius on the rocker stud and the fit to the replacement pushrod before reassembling. Also double check that you're not into coil bind or that the retainer is not bottoming out on top of the guide but I would think either of these scenarios would be bending the pushrod rather than promoting a premature wear problem.
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By charliemccraney - 16 Years Ago
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Well, I haven't paid attention to the mileage but I've had one of the other old pushrods in there for at least 200 miles. No sign of trouble! Tonight I put the last new one in. So it looks like things are well concerning this issue.
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By 56-Vicky - 16 Years Ago
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So is the final diagnosis a soft rod?
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By charliemccraney - 16 Years Ago
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I'm really unsure of the cause. I don't think it was a soft rod. It had been on the old engine for 10k miles and looked good when I installed it in the new engine and worked fine until I installed the Dove rockers. It is the same cam, lifter, and pushrods I had in the old engine, in the same block, in the same positions. I think it is either oiling after installing the Dove rockers, as Ted mentioned, or maybe I got some trash in the cup when I installed the rockers.
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