ticky crate motor....

[chrisII]

ive got a 96? (i think) 380hp magnum crate engine in my duster. im told its still pretty low mileage as neither the duster or the pickup it was in prior have ben a daily driver. i was told 4k when i bought it , i may have another 500 to 1000 miles last summer. my question is do these things normaly have a top end tick? I know most magnum engines had some lifter noise , but this seems louder than the standard magnums ive owned. Im sure of the 5k on this engine its lucky if 1500 were eazy miles. I hear storys all the time of the prior owner scareing the crap out of people in this thing! im pretty tame with it , i swaped out the 391s for 2.94s to get it to be a mellow hiway cruiser, but still tend to get heavy on the loud pedal alot. oil psi is around 60 hot so im not to worried about bottom end just curious if the noise is normal and if there is an easy fix.

[Aussie Challenger]

Check to see if the noise increases as the rev's increase or quietens down. If noiser lift the cover and check if the rocker is loose, the bolt may have come loose. Check to make sure that it is getting oil up the pushrod as the magnums oil the overhead gear through the push rods. You can check to see if the valve has any sideways movement with a long screw driver or similar bar, but be carefull not to put too much pressure as damage can occur. Also by turning the motor over by hand look at the offending valves as they are pushed down by the rocker, if the valve guide is loose the first movement will be a sideways movement instead of down. This could be your problem and then you will need to make a decesion to pull the heads and have new guides installed or let it go a while longer.
  Also push down on the push rod end of the rocker with the valve closed, use your hands, if it goes down the lifter is at fault.

  Rotate the push rods by hand to make sure that none are bent, they will wobble instead of go around smoothly.

  David

[Chryco Psycho]

there were a lot of bad lifters in the last few years so probably 1 or 2 lifters has gone bad , make sure the cam is ok too , with the reduced Phosphorus & Zinc it could have killed the cam too

[chrisII]

thanks guys, tomorow is the first show of the year for me, and only about 15 miles each way. im guna chance it since its ben noisy for a year already i dont think the eazy drive will break anything. illpull the covers before i do any beating on it. are the magnum crate motors an adjustable rocker or are you saying a rocker hold down could be loose?

[Aussie Challenger]

I haven't had the top off of one yet, but I believe they are not adjustable,  not too many magnums in Aussie. C.P. would be able to confirm this.

[chrisII]

thanks , ive never pulled the valve covers on any of mine either. back when the magnum head / la shortblock convershon was "the hott ticket" im sure i knew the whole gig, but never did it an can only remember about 1/2 of what i read 10 years ago..gowd i must be getting old, i used to know everything

[chrisII]

in driving it today i realised that the tick is loudest under light load, in the 1500 to 3000 range. it soesnt do it loud at idle, or when im on it. pretty much i wonder if it just doesnt know how to act when it isnt getting beat lol

[Chryco Psycho]

being ball stud design you could be just out of adjustment

[chrisII]

so , they are adjustables then??

[Chryco Psycho]

I believe so , , I haven`t worked on a Magnum for a long time

[wiging19]

My engine had the same issue.  Turned out that one of the springs had broken.  After the spring was replaced and we adjusted all the remaining springs it didn't make a sound.  The guy who helped me replace the spring told me he had never seen a spring break like that before.  Especially one that had as few miles as I put on it a year.

[moper]

It could also be pining you are hearing...maybe take a friend who might know better for a ride...Or try running the tank down, and adding a couple gallons of race fuel to see if it goes away.

[chrisII]

its not a ping, im sure of that. its deffinately valvetrain noise. ill have to pull the covers an check things out. just wanted to ask here if this was a normal thing first.

[chrisII]

pulled the valve covers tonight, all the rockers seem to be tight, in fact they dont seem to have any travel or give in the lifter. im new to hyd rollers but it seems that hyds always had some give.* the engine had just run to drive into the garadge when i checked em.

[moper]

Magnums are pedestal mount. Not preload/pivot ball. So once they are torqued, that's it as far as I know. If it hasn't been run in a while, perhaps there's just a few lazy lifters...Like anythign else, ther is a spec for lifter preload, and like any other MP crate, they dont ever measure it. And they use every part, even if there is an issue, so, if it was never quiet, it may have something like the pushrods are too short, or something wore a little too fast. Only taking apart and lokking will fix it. Unless we happen to guess right..