hixwv

Hey guys just got a 98 SS with 60k on it and I'm trying to diagnose an engine sound. It wont make it on a cold start, takes a few minutes to make it at idle and its worse point is around 1800 rpm give or take 100. You can hunt for it on start up and it will make it right at that rmp range but once it warms up its constant. I put some videos on youtube. The top one was after a well due oil change, but it was already warmed up and idleing at 1800 when I started recording, other two were a few days ago before oil change.
www.youtube.com/chriz2000wv

tell me what you think.

DANZWS6

iTrader: (67)

sounds like a rod letting loose. how oil psi?

lvbroham1

Sorry about the let down, definitely doesn't sound good. I'd suggest as a start take off the valve covers and see if there is any visible damage.

hixwv

oil pressure is good. can i check/change push rods without taking the heads off? at one point the other day when it was warm we all agreed it was coming form the passanger side....but im not positive now

O2Form

I watched your video and the oil pressure looks a little low. Warm the engine up completey and let idle. You should have 40 psi. Also make another video and rev it suddenly from a idle but not high. If its a rod bearing it will tap badly.

hixwv

I should be able to get another video up in the next day or so. But if it is something bad, like the bottom end or a spun rod I dont want to drive it. So I wont put it on the road aka make her legal. And since I probably wont be able to come up with a few thousand dollars to rebuild it what is the car worth as is? like I said it just turned over 60k. shes a 7 or 8 out of 10.

vetteboy99

It needs a motor for sure, prolly worth around 5k max.

O2Form

Didn't you hear this before you bought it?

hixwv

yeah I did. Got it really...really cheap. hopefully i can get a rebuild cheap also.

hixwv

Didnt have time to do anything today but move it. But when I pulled it in today I noticed the psi was well above 40 on COLD start up, and of course the mystery sound was nowhere to be heard. just not sure about warm yet. Kind of hate letting it warm up but I guess the damage has already been done? If it needs rebuilt, is there a chance the block might be ok? because arnt the 98 blocks super think and cant be bored? even if i do have it done id want it stock

KevinR

Yes, you can. Just pull the valve covers, and rockers and you can get to the pushrods. Honestly, I've bent a pushrod before, and it kinda sounded like that. I guess you can expect the worst and hope for the best on this one. It's hard to tell from the video, but is the sound coming from the top?

1998Chv37s

Does it get worse with rpm? Def in the top end from what it sounds like but its damn near impossible to tell from the vid

technicalninja

iTrader: (1)

I'd pull valve covers first before worrying aboiut what I was going to do or purchase.
That might be caused by the rollers coming out of the rocker arm (appears to be a common thing).
Search "trunnion upgrade" for more info. One of the common complaints was a "sewing machine" sound coming from the top of the motor.

Diagnose first. everything else second!

vetteboy99

x2, pull valve covers off. But don't start it on! lol

5.3LJimmy

iTrader: (10)

With the scraping noise it sounds like it could also be a rocker arm that has puked out it's bearings. I would definitely pull the valve covers and inspect the rockers and pushrods first.

hixwv

either today or tomorrow im going to try to do that. and also here in a little bit im going to go get a mechanics stethascope and see if i can narrow anything down while its cold and barley making the noise. also how can i tell if the rock arm is bad? and if i find the bent rod is it as simple as putting a new one in it, tightening the rocker arm bolts to 22lbs, and putting the cover back on? that would be too good. but like you said...hope for the best expect the worse.

KevinR

Yup. Pushrods are easy to change. If it's a rocker, you should be able to see it right away.

O2Form

cold oil pressure don't mean nuttin, get it hot then it look at it. I watched your video, the oil pressure looks funky.

hixwv

define hot...i dont want to hurt it any worse..but ill let it warm up again. the pressure has always looked good

hixwv

ok...should be another video up in a second from inside the car, warmed up, hot. showing oil pressure...

www.youtube.com/chriz2000wv

the one uploaded today