My winter Mamo build is (mostly) done!
Scanned the paper, it's all I've got right now.
Definitely something going on above 6K, but look at that torque curve! Or I should lack of a curve - that thing is flat as a pancake...
Once we get this valvetrain issue sorted I think it ought to break 450 easy.
Brandon - nice BS-ing with you too! Like I said I didn't know a soul there and was just kind of wandering about looking at the cars...
Definitely something going on above 6K, but look at that torque curve! Or I should lack of a curve - that thing is flat as a pancake...
Once we get this valvetrain issue sorted I think it ought to break 450 easy.
Brandon - nice BS-ing with you too! Like I said I didn't know a soul there and was just kind of wandering about looking at the cars...
Believe me I wanted to. But it was late in the day and I didn't bring any tools. I wasn't going to ask the RPM guys if I could borrow some, I know how techs are with their tools...
Talked to one of the guys at RPM, they said it's a bad lifter... I was kind of surprised at that and didn't have time to think and we only talked for a minute or so... I'll call back tomorrow and get more details but I'll likely be going back up to trailer it home for fixin' time.
I edited my previous posts about suspecting the rockers. YT has caught enough flack in the past but their newest design is much stronger and there's no sense in badmouthing a product that didn't fail.
Rob
I edited my previous posts about suspecting the rockers. YT has caught enough flack in the past but their newest design is much stronger and there's no sense in badmouthing a product that didn't fail.
Rob
That sucks man, gotta pull the heads again. Why is nothing easy? Well, I'm off to go pull my heads again. Know you have a brother in arms with a cranky wife, a flat wallet, and sticky lifters. Beats the hell out of my cubicle though.
AND, when you get it back together you'll be able to pull stumps with it.
AND, when you get it back together you'll be able to pull stumps with it.
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Yep, spot on. And in my case, it didn't. I had to pull the lines and flare them on the bench with TWO of the flare tool clamps back to back to keep the lines from pushing through. The factory lines are hard as nails. Actually, harder.
Talked to one of the guys at RPM, they said it's a bad lifter... I was kind of surprised at that and didn't have time to think and we only talked for a minute or so... I'll call back tomorrow and get more details but I'll likely be going back up to trailer it home for fixin' time.
Rob
Rob
Bad lifter as in failed roller wheel is not a good thing.
Ron
I got the car back late Tuesday night, started ripping it apart last night, pretty sure I'll have the head off tonight...
I got a better dyno sheet showing all three pulls:
Totally weird how the dip keeps moving down in the RPM range on every pull. Lockup clutch slipping and getting worse? Trans slipping(trans is 100% stock btw) and getting worse? Or is this a valvetrain issue(lifter on it's way out?)?
Can't really know for sure, but I'm leaning toward trans/lockup clutch...
I got a better dyno sheet showing all three pulls:
Totally weird how the dip keeps moving down in the RPM range on every pull. Lockup clutch slipping and getting worse? Trans slipping(trans is 100% stock btw) and getting worse? Or is this a valvetrain issue(lifter on it's way out?)?
Can't really know for sure, but I'm leaning toward trans/lockup clutch...
Diagnosis complete! Collapsed lifter for sure, with no collateral damage! 
Parts...
Culprit on the left, see the puddle of oil? That's there because the pushrod cup is sitting at the bottom of its travel.
Rollers have very very fine scoring on them, I'm ok with it as I think they (and the cam) are still breaking in. All of the drivers side wheels look the same. Thoughts on this?
Tony told me to go ahead and pull the good one apart to see exactly what was going on in there - the bad one won't come apart as the plunger is jammed down at the bottom. I didn't really mess with it much, though, in case Comp wants to do it themselves.
Here's the plunger out of the good one, notice the scuffed spot...
I suspect these things are REALLY tightly toleranced. No idea how or why one collapsed, though.
MAJOR HUGE thanks to Tony for helping me through this. He even gave me his home # and we had about four separate conversations last night. "Do this". "Ok call ya back in 5". THAT, my friends, is what you call customer service.
I reckon I'll get a replacement and give these babies one more shot. If this **** happens again I'm going with something else.
Rob
Parts...
Culprit on the left, see the puddle of oil? That's there because the pushrod cup is sitting at the bottom of its travel.
Rollers have very very fine scoring on them, I'm ok with it as I think they (and the cam) are still breaking in. All of the drivers side wheels look the same. Thoughts on this?
Tony told me to go ahead and pull the good one apart to see exactly what was going on in there - the bad one won't come apart as the plunger is jammed down at the bottom. I didn't really mess with it much, though, in case Comp wants to do it themselves.
Here's the plunger out of the good one, notice the scuffed spot...
I suspect these things are REALLY tightly toleranced. No idea how or why one collapsed, though.
MAJOR HUGE thanks to Tony for helping me through this. He even gave me his home # and we had about four separate conversations last night. "Do this". "Ok call ya back in 5". THAT, my friends, is what you call customer service.
I reckon I'll get a replacement and give these babies one more shot. If this **** happens again I'm going with something else.
Rob
Last edited by Rickenbackerman; Apr 27, 2012 at 04:59 PM.
Interesting.
There appears to be a fair amount of scuffing on the lifter bodies as well.
And I hate to say it, but the roller wheels on my 80K mile lifters look new, no such scoring marks.
Were the lifters and lifter bores measured for lifter to bore clearance? Lifter bores honed?
Dirt in the oil maybe?
Ron
There appears to be a fair amount of scuffing on the lifter bodies as well.
And I hate to say it, but the roller wheels on my 80K mile lifters look new, no such scoring marks.
Were the lifters and lifter bores measured for lifter to bore clearance? Lifter bores honed?
Dirt in the oil maybe?
Ron
Interesting.
There appears to be a fair amount of scuffing on the lifter bodies as well.
And I hate to say it, but the roller wheels on my 80K mile lifters look new, no such scoring marks.
Were the lifters and lifter bores measured for lifter to bore clearance? Lifter bores honed?
Dirt in the oil maybe?
Ron
There appears to be a fair amount of scuffing on the lifter bodies as well.
And I hate to say it, but the roller wheels on my 80K mile lifters look new, no such scoring marks.
Were the lifters and lifter bores measured for lifter to bore clearance? Lifter bores honed?
Dirt in the oil maybe?
Ron
I'm not really sure what's up with the wheels... I did drain the oil last night - only a little bit of metallic slime on the drain plug and there was no dirt or grit in the oil that I could detect. It looked slightly (and I mean ever so slightly) dirty but the entire top end is brand new and still breaking in.
Oh my! I believe you just identified the problem.
My builder would have said "the engine comes apart and the lifter bores honed for these lifters". Period, no discussion.
Or choose different lifters.
I'll bet Comp says the same thing. And I'll bet those lifters are just ever so slightly oversize compared to stock. Or Comp built them wrong.
I assume you had to rub on all of them?
My builder would have said "the engine comes apart and the lifter bores honed for these lifters". Period, no discussion.
Or choose different lifters.
I'll bet Comp says the same thing. And I'll bet those lifters are just ever so slightly oversize compared to stock. Or Comp built them wrong.
I assume you had to rub on all of them?
I did have to rub on most but not all of them. Actually now that I think about it I don't think I had to rub the failed pair at all. The bores on cylinders 1 and 2 were by far the tightest, and the lifter that failed is the #7 exhaust. The "scuffing" you see is just from general deburring - these things come pretty rough around the edges out of the box, especially around the axle. These particular lifters came out of Tony's 454 and they worked fine in his motor. He had already deburred them but I spent even more time on 'em with the wet or dry.
I did measure the OD's at a couple of different places (with a dial caliper mind you - not ideal - a mic would have been much better) and as far as I could tell they were all uniform and the same diameter as stock.
I really don't think tight lifters is the problem here - I meticulously massaged EVERYTHING (lifters and in some cases the bores as well) until everybody rode smoothly and made a nice soothing "clack clack" when grabbing the link bar and smacking the set up and down onto the base circle.
I'm gonna cut the oil filter open this weekend and see what's what.
I did measure the OD's at a couple of different places (with a dial caliper mind you - not ideal - a mic would have been much better) and as far as I could tell they were all uniform and the same diameter as stock.
I really don't think tight lifters is the problem here - I meticulously massaged EVERYTHING (lifters and in some cases the bores as well) until everybody rode smoothly and made a nice soothing "clack clack" when grabbing the link bar and smacking the set up and down onto the base circle.
I'm gonna cut the oil filter open this weekend and see what's what.