last try for answers

i have asked before in the 94/95 forum, but more people use this one. this is the last time i'm going to bother everyone.....

i have a new engine in my car. i used a 2000 explorer block and internals, documented 6k miles. i put the engine together over the summer, on a stand, and installed it in october.

i installed a steeda #19 cam, thumper heads, stock valve sizes, springs rated for .550" lift.

i have valvetrain noise, a general loudish sewing-machine grumbling, plus a tapping noise that sounds like a bad lifter, sort of around cylinder #3.

i have used 1.7 crane cobra roller rockers. i have used stock stamped rockers.

i have used pushrod lengths from the stock 6.250 to 6.300 to 6.350 with every possible shim size in between. the stockers are noisey with either set of rockers. the 6.300's tighten down right 3/4 to torque at 25lb/ft., but are still noisey, and same tapping. the 6.350's are waaay too long, but just for kicks, i tried them anyway. no difference in noise.

i have tried different valve covers. fox bodies were actually noisier, maybe due to the larger area under aluminum covers. swapped back to stockers. no reason for taller valve covers with stock rockers and only .480" out of the steeda cam.

rio (andy) gave me two lifters to swap out of cylinder #3. i did so, no change.

the kicker came when i swapped out a perfectly good full set of lifters, with only 8k on them, for a BRAND NEW full set of fms lifters, only to have the EXACT same noise level. i did this because i thought i may have been mistaken, and it may be #4 or #3, so just to be sure, i changed all of them. i even took the time to change the positioning of every rocker, so as not to have them working on the same valves. everything is new, so it isn't bloody likely to have much wear time.

the tapping seems to come from cylinder #3, but there are no signs of anything different in that area, i.e., no difference in the way #3 tightens down, no excessive wear on the valve tip, rocker, or pushrod, and no difference in the lifters when i took them out.

the rockers do not hit the springs. they do not hit the valve covers. the valves are adjusted within spec. hell, i have adjusted them waaaay out of spec just to see a change. nothing. i have taken the top end apart 24 times, and taken the lower intake off 3 times, even to the point of replacing the explorer lifter-holddowns and spider with the typical 5.0 dogbones. nothing.

i have great oil pressure. 43lbs. at idle, moving up very quickly with rpm.

before i take the engine out, sell it part by part, and blow $4k on a crate engine, someone PLEASE TELL ME I'M NOT F'ING CRAZY. i need a fresh take on this.

1) injectors are old. from the old engine. but, they didn't make this noise on that one, and the noise isn't the pleasant little injector chattering.

2) louder than a minor exhaust leak, placing a dowel rod on the valve cover confirms it's valvetrain noise.

3) haven't tried new heads. that's a lot of work, and a set of head bolts and gaskets. i don't want to do that and then find out it's the block (bad lifter bore, etc.) if those heads come off, it'll be with the motor out because i'm putting in a new one.

4) yes, have used a feeler gauge 22 times.

5) not really loud, but louder than i am comfortable with. i don't know if i can just let it go, seeing that it took my free time for 4 months to build it right, or so i thought.

thanks for your questions. you may have confirmed for me that it has something to do with the heads, or at the worst, the block.

uh, i stated in my original post that i have used the stamped steel 1.6 rockers, the stockers. i am using them right now. no difference in noise whatsoever.

it is not p/v clearance. thanks for the attempts.

[Have you looked at the heads/block to see if maybe the pushrods are hitting rubbing anything? I still haven't pulled mine apart yet to see if it's actually a pushrod or not but I'll let you know when I do. Mine only taps at low rpm/idle & I have great oil pressure (high vol) does yours only do it through a specific RPM band?[/QUOTE]


the pushrods are unmolested when i remove them. they show no signs of rubbing or wear, nor do the rockers, valvetips, valve covers....it's like the sound SHOULDN'T be there.

the tapping is there at idle and at redline.

by the way, the heads are ported E7's with stock valve sizes. no chance, no way no how, that there is p/v clearance problems. the cam isn't near big enough, nor does it have enough duration to worry about.

....unless the Explorer pistons are substantially different from those used in the Mustang 5.0's? Still, they'd have to be woppers to hit with those tiny valves.

gearheadboy said:

So I'm a dip**** mechanic, what happens if at idle,(tapping) you pull the plug wire on #3. Does the noise get better? or jack the advance way up. does it get better. Know where I'm going? I think its a pin rattle. TRY IT, I GOTTA KNOW. Does the thing miss? I'm guessing with a .480 lift cam it ain't all that rough at idle that a miss would be hard to pick up. Have you run it without a valve cover an watched it? I know its a pita but I'd do it. Put tension on your rocker with your fingers while it is running and see if you can change it.

Click to expand...

gearhead, do you mean connecting rod pin? wouldn't that be a faster tick, though? hell, i'll try it and see. it's not a bad idea.

i have not run the car without the valve cover on. i'd love to do that. thanks for the ideas.

i disconnected cylinder #3 and there was NO change in idle! upon revving the engine a bit, you could tell there was a miss. no change in tapping noise, either at idle or at higher rpm. (this was only for 30 seconds or so)

what i didn't do was try #4 or #2. maybe that would've been more telling.

what does that mean? maybe not full compression? how would that contribute to the valvetrain noise? valves not fully closing? bent valves? bad seats?

what i did notice was the msd coil i had was arcing quite a bit. (lights out, glow around coil body.) so, i got THAT going for me.

but Ashford, would'nt oil pressure be off a bit with a crack in the block in that area? mine is very high.

the lifter noise was IMMEDIATE when i started the engine after building and starting it. nothing happened to cause it. the shortblock was part of a perfectly running engine (only 6k miles on it, verified) when i got it, stripped it of all parts except crank/pistons/rods rotating assembly, then built it.

my assumption this whole time has been on the parts i have assembled EXCLUDING the shortblock. is that a bad assumption?

i still have the stock gt40p heads the motor came with. the rockers/rocker arms/lifters/pushrods look amazingly new and there are no signs of wear or abuse on them...i've looked them over as well very carefully looking for clues. i am contemplating re-installing that stuff, but i don't want to waste a days work if it may be a cam/block issue.

any thoughts?

very interesting about the "solid lifter" issue. that's what i was trying to accomplish using .635" pushrods. they were obviously too long, but i was going along with the thinking that i would take all of the "lift" out of the lifter. it compressed the lifter nearly all the way. there was no change in the noise, at least compared to .630 pushrods.

as far as oil on the rockers, a quick disassembly after running the engine (about 9 minutes now!) reveals lots of oil, puddled in the stock rockers and along the bottom edge of the head. i did that just for the purpose you spoke of...is there oil getting to the rockers? the answer is yes.

spring pressure....so, the springs are spec'd to .550 lift, so says thumper. i can't imagine that being to much for the valvetrain. is the thinking that spring pressure being too high actually collapses the lifters?

the oil pump is stock-strength unit. not a high volume.

thank you very much for the insight.