wjogert

1996 Camaro Z28, stock LT1, 6-speed

Ok, I've had this noise from the engine for a few years. I don't drive the car regularly, so I've taken my time in chasing it down... not to mention it never sounded really serious.

At first, my PS pump was leaking and I thought it was the culprit. Last spring I replaced the pump. Fixed the leak, but not the sound. It sounded like it was in the water pump area, and i wanted to replace the OPTI cap and rotor, so decided to replace the WP too just for good measure (I mean, not like these pumps let go often, lmfao). Got old one off, and bearing was fine. Heard rumors of the distributor making such a noise, and the shaft seemed a bit loose, so replaced that too. Noticed that the water pump drive seemed to have some play also, but wasn't prepared to go any deeper at the time. Well, reassembled and noise was still there.

So, now I was convinced that I needed to removed the drive, plug the hole, and convert to electric water pump. That was last fall. I've been planning that repair since spring and haven't had the time yet.

Well today, I started the car again (try to once or twice a month). The noise is insanely worse, and now seems to be more mid-upper engine and emitting from the pass. side... with an occasional clack similar to a lifter tap.
I'm thinking spun cam bearing or stuck lifter roller?? Aside from the noise, the engine runs great and is quiet from the bottom, except for a leaking exhaust gasket at the pass. side of Y pipe.

I have links to YouTube vids that sound exactly like mine.
[autostream]http://autostream.com/camaroz28/?page_type=firebirdplayerthumbnail&framepage=2685& transactionid=1343503492-1842020995&posted_by=wjogert_www.camaroz28.com&you tube_video_id=bQOwx6uYCjE[/autostream]

I've read almost a hundred post on various forums, all for similar sound, but NOBODY has ever posted a fix... except one guy who said the roller on #6 exhaust lifter looked like someone hit it with a chisel.

Car has almost 150,000 miles. I'd love to pull the motor and completely rebuild it HOT, but I'm quite intimidated. It looks like a nightmare to pull this motor out without a lift. So, I'm looking for opinions. I could tear off valve covers and intake, and check the lifters. I could pull the front cover, replace the cam and lifters, and remove the WP drive. Or someone could tell me that it really isn't that bad to pull an LT1 from the top?

I'm also hoping that maybe a few of the other LT1 owners who have encountered this same noise will also chime in and reveal what finally fixed theirs, before I go tearing down.

:-)

shoebox

I'd be looking under the valve cover, first.

wjogert

Thanks for the replies.
If it were as easy as just looking under the valve cover, you bet that would be my first move. I have to remove intake to look at the lifters. But, that is what I have decided to do... pull covers and intake and check out the damages BEFORE I decide how much further to go.

BTW, I am not a newb/amateur. I worked in GM parts and service for 13 years, and was a backyard mechanic long before and after. I have done probably half a dozen full engine builds, none of them stock, lol. And before you ask, yes I know how to "build" a motor and not just buy the biggest parts in the Summit catalog and slap them all together (and subsequently wonder why the motor runs like crap, lol). My only intimidation in the engine rebuild is pulling the motor from the top, as there is little clearance and the motor is set so far back. It looks like a royal PITA to do? But, I don't have access to a lift anymore.

Anyway, as I said... I think I'll pull the top of the motor and see what the lifters look like. If it doesnt look like it's dropped too much debris into the bottom, I may just do the simple fix. If it looks bad, I will plan to pull the motor and rebuild it in the basement over the winter

dzltek

I'm a diesel mech. and removing the engine can be a little intimidating, but its not bad at all. Put it on jackstands disconnect the exhaust at the cat, drive shaft and torque arm, remove the steering shaft, take master cylinder off, disconnect computer, ground wires, and you may have to take the brake lines off of the abs block. Then you are almost ready, need to unbolt the trans crossmember. Then you put the car back on the ground, take out the 6 k member bolts. Hook your engine hoist to the car, I used a chain around the core support and lifted the car up, put the jack stands back under it, rolled the engine and trans out. My first time doing it took me 4-4.5 hrs on a hot July day so I know it can be done faster. I probably missed something but that's the quick/short version

77amc

Try listen to this.. Might help.

[autostream]http://autostream.com/camaroz28/?page_type=firebirdplayerthumbnail&framepage=2706& transactionid=1347240014-76107180204&posted_by=77amc_www.camaroz28.com&yout ube_video_id=cW_wpE3hG5k[/autostream]

E

wjogert

UPDATE!! FIXED!!

So, a mere 4 years later I finally got the time and motivation to attack this issue. Haven't driven the car except to store it in 2013.

My prime suspect was the culprit. Bad lifter roller and damaged cam lobe. I expected to find the roller bearing frozen, but it spun freely. #2 Intake.