454 Mag Valve Job?

[Air 22]

Anyone have an IDEA as to the sign's to listen/ look for of a possible valve problem? My eng is a 1995 454Mag/Carb w/ no history of problems approx 400hrs on it. spinning a 23 = 5400rpm trimmed out... which is to high and have addressed that w/ a new prop to max at 4800-5000 rpm. After WOT for just a few seconds then down to idle after a slow thottle reduction @ idle I hear a light "ping" :( on the upper portion of the engine...like a bb in a can that goes away after a few minutes. The sound can only be heard below 1000rpm and is rpm responsive. If i run the engine at lower rpm cruzing 2500 to 3500-4000 the sound does not occur(that i can hear). It only appears after WOT. I only run WOT just to check speed the back off. Most use is at 3000-4000 rpm. The higher rpm is only achieved during these colder days which results in more HP which i think might have caused a problem. I'm not sure if a lifter might be sticking etc... Change the oil every 25 hrs. all other eng indication are normal. If i loose a valve running then my motor might be toast and i hope to avoid that .... :confused: What costs would be acceptable for this type of repair etc???

[MOP]

I would try a pint of Marvel Mystry oil and re-adjusting the valves which many people never do. See what happens in a few maybe 2-3 hours.

[BUIZILLA]

Dwight, when you bring the boat down next month, we'll listen to it. In the meantime, don't sweat it. I have the leakdown tools, and everything else to check it out. I doubt your hearing a ping at idle. Maybe a loose rocker or a broken valve spring though...if the noise goes away, it's not a valve spring.. if the noise slightly follows the engine rev on snap throttle and doesn't quite follow the revs on snap decell, it's a lifter.

J

[Air 22]

J... ok really appreciate the help. The sound is not there on start up...only after WOT and then it lasts for a few minutes. If I drive around for 3-5min at at idle or just above the sound goes away and does not return. The sound can only be compared to a BB in a large coffee . Its not a deep sound but a very light one. Think its ok to run b4 we come down in FEB? Thinking of dragging a mechanic out w/ me to try and diagnose the sound? I hope running it cruzing isn't going to drop the valve? :confused:

[BUIZILLA]

It almost sounds as if it's slightly overfilled on oil, and aerating from crank windage in the upper rpm range. The foamy oil stays up top in the heads until it has time to drain and *reclaim* itself. Not sure what oil and filters your using? The fact that it goes away, and also is not there on cold startup, is comforting.. pull the plugs and read them a.s.a.p.

J

[Air 22]

I'll ck the oil level again. It made the sound b4 i changed the oil...then changed the oil 2 wks ago...i use Castol Heavy Duty straight 30 weight and a high performance Moroso(chrome) oil filter. what should i look for on the plugs? Havn't run it for 2wks ..should i fire it up on trailer warm it up then pull plugs or just pull them now?

[BUIZILLA]

A) I hate Castrol oil.
B) Moroso chrome oil filters are junk.
C) Castrol oil is junk, except maybe their fully synthetic blends.

Go with GOOD 15w40 mineral oil or 15w50 Mobil 1 and a FACTORY oil filter, and see what happens.

[Air 22]

ok..will do and i'll try a good 15w50 mineral oil...i'm a little affraid to change to 15w50 Mobil 1 as my eng has never had anything but a straight 30 or 40 weight oil.
D

[BUIZILLA]

Go to your local Texaco quick oil change place and get their 15w40 HD oil. Good stuff. Stay away from Castrol, Quacker State and Pennzoil.

J

[Donzigo]

Air 22 -------- stay with your 40 weight oil, for sure. Sounds like your engine is still revving too high. I think the specs say 4,400 to 4,600 is about right. Still trying to imagine the sound and when it's heard. Sounds like a lifter, not a valve?????

[Hanker]

Oye....Buizulla, I know the story with Quacker State, but why don't you like Castrol HD? Any specific stories.....

[KMLFAMILY]

Install a known good mechanical oil pressure gauge.Take note of the pressure when the noise occurs.Sounds like oil breakdown or plain old worn engine,excessive clearances(just can"t hear it from here) wink .I also believe in a straight weight oil in an older(worn)engine.Old school thinking.I would raise it to 40w and perform ck"s.