CanHearEverValveRattleOnLongExtendedTrips

[ERIC95TAHOE]

so im beginning to think this is really what chevrolet stands for. i posted a while back about my 95 tahoe, ratteling and clattering when cold, ok what mid 90s chevy truck doesnt? well i got over that, just put a new cat in because i was tired of listing to the raspy tin can sound my truck made under a load. anywho, that problem fixed, now i can hear my engine lol, i hear a faint clattering around about 2000-2500 ish rpms im thinking valve adjustment, what do you guys think, or am i just picking out every noise now and complaining about nothing?

 

[SunlitComet]

Can you be more specific on location on engine or description of sound. It sounds like a loose metal part at first thought if within a specific speed range. Does that new cat have a loose heat shield?

 

[ERIC95TAHOE]

its defiantly coming from under the hood, it did it before i replaced the cat and y pipe, just couldnt hear it as well as i can now that its quiter haha. i do have a heat shield rattleing from time to time so i know its not that sound, think it would be a good idea to check valve lash? i dont know how many miles are on the engine, it was supposedly rebuilt and had 1000 miles on it when i got it, but i doubt that, i know its not the original engine, i was told it was a 305, but i checked the numbers and it is a 350 haha so someone lied to me or the guy i got it from

 

[SunlitComet]

305 was probably a typo on his part. Heat shield sounds can change as they seperate further. Since you are in a speed range I would not go after valves just yet something must be loose elsewhere. Could use a mechanic stethoscope to pinpoint while reving your engine while parked. If it is your valves it should also happen then.

 

[ERIC95TAHOE]

thanks alot, ill check around see if i can hear it while reving the engine. ill post back when i get some time to do that, it will probably be a few days.

by the way it clatters loud pretty much all the way to operating temp. then it goes away once its warmed up but it makes faint sound that sounds like that clattering, only at the certin rpms like i said, if you get what im saying?

 

[SunlitComet]

What about loose bolts or nuts on spark plug heat shields or metal heat riser stack on the right manifold?

 

[ERIC95TAHOE]

that very well could be, this thing looks like it was put back together in a hurry, a while back i had the brake light coming on and blower motor stopping randomly, found out i had a loose bolt that was a ground on the back of the block. they smashed the cover to the abs putting the engine back in, i found a few wrenches under the hood, and the oil pressure sending unit was loose leaking oil i paid too much for the truck but it was what i wanted looks wise haha. ill check some heat shields under the hood and see. maybe i can get a recording of driving it and some sound if i get some time, to get you a better idea of what im hearing if it shows up.

 

[oldsalt]

What oil are you running in it and what is your oil pressure when the clatter happens?

 

[ERIC95TAHOE]

well this is a very over due reply, i have been listening to it every day now since then and thinking. i run 5w30 in it, ran 10w30 in it once (made no difference) Its only when the engines cold and its cold out side, according to my gauge when its cold cold its about pegged at 80psi. its not a valve noise, i poked around and did some listening and ruled that out. it will do it if you idle it and bring the rpms up when its cold too sometimes. now that its getting warmer out it doesnt do it as long because it warms up faster

 

[retorq]

Piston slap?? How many miles??