Posted By: runnerrt
Wiped Out My Cam What To Look For As Cause - 08/19/13 07:46 PM
Driving my Bee home from a show a couple weeks ago, I noticed a tapping in the engine. I tore it open this weekend and the #8 exhaust lifter is concaved and looks like the lobe is shot. The engine is a 383 with MP 509 cam that was built 23 years ago and has about 10k on it. I just put a set of MP aluminum 452's on it a couple months ago (300 miles), stock rockers with correct length push rods. I am going to pull it clean it out and put another 509 in it for now, until my 489 stroker is done. I do not want it to happen again, What possible causes should I look for? Thanks.
Posted By: Rapid340
Re: Wiped Out My Cam What To Look For As Cause - 08/19/13 07:52 PM
Could be that the new heads have spring pressure that is too high or some kind of interference or binding taking place.
You are using good flat tappet oil I assume.
Posted By: RapidRobert
Re: Wiped Out My Cam What To Look For As Cause - 08/19/13 07:58 PM
poor metallurgy. not enouugh zinc. poor breakin procedure. lifter not free (enough) to rotate in it's bore. too high of spring psi on breakin. 23 yrs is a long time/alot of history
Posted By: rbstroker
Re: Wiped Out My Cam What To Look For As Cause - 08/19/13 08:03 PM
The MP 452's (straight plug Eddy's) have a spring rate compatible with the 509 cam. After all those years, I would have to guess that you didn't have enough zinc additive after the last oil change. I use 1/2 bottle Lucas break-in additive with Rotella diesel oil. So far; so good.
Posted By: runnerrt
Re: Wiped Out My Cam What To Look For As Cause - 08/19/13 08:33 PM
I run Valvoline VR1 race oil, it claims to have high zinc content
Posted By: JohnRR
Re: Wiped Out My Cam What To Look For As Cause - 08/19/13 08:47 PM
In that case it was either the oil , doesn't take long for the lifter and cam nose to go away once the metal transfer starts , or the lifter stopped rotating , obviously , for some reason. New pushrods ? How much preload ?
Posted By: Dodgem
Re: Wiped Out My Cam What To Look For As Cause - 08/19/13 11:07 PM
after 23 years probably enough dry starts to start some cam wear then it all of the sudden goes like crazy!
Posted By: Dcuda69
Re: Wiped Out My Cam What To Look For As Cause - 08/19/13 11:50 PM
My buddy lost his MP .528 solid after many years and many miles. He had not touched a thing and poof one day lobes gone bye-bye. Think strongly about a roller for your new build
Posted By: Supercuda
Re: Wiped Out My Cam What To Look For As Cause - 08/20/13 12:55 AM
Did you measure the retainer to guide clearance at max lift? Just a thought.