Is this normal for the 3.4?
 

Hi everyone, I just bought an 04 Alero 3.4, and I got it cheap because of an engine noise. The guy that had it thought it needed an oil pump, but in my experience you usually need an engine before an oil pump. However, the previous owner had the heads redone, and they look brand new. I'm getting a real bad tap in the top end, especially above 1000 rpm. I took off the front valve cover to check the oiling, and it looks like some rockers are getting a little oil, and some are not.

The oil light works because it comes on at test, and the sensor is plugged in, but it does not come on when the car is running. It just seemed like it should be getting much more oil to the top to me and I am wondering if the noise is a collapsed lifter or two. But at the same time I can't imagine someone doing the heads and not replacing the lifters and push rods while they are that far down. I posted some video below, please let me know what you think so I know where to go from here. I was suspecting the oil pump, the pump drive and or seal being damaged when they jacked the heads, and now maybe a collapsed lifter. Any ideas?

http://youtu.be/ehdAgC6vUl8

http://youtu.be/lc-MlBSw-Nk

http://youtu.be/3mbYbn80aW0

Usually, id tell you that is normal. The 3400 motors have a loud valvetrain. And also piston slap. But its usually not THAT loud nor terribly noticable.

Did you check the back too? Id suggest running an aftermarket oil pressure gauge. The stock oil light really only comes on when the motor has already had its damage of low oil pressure.

Thanks for your input sleepyalero, I appreciate any info I can get on this, and I talked to a guy who owns a shop nearby today. He seems to think the valves just weren't adjusted properly when the heads were done, and that would cause the oiling problem and the subsequent noise on the badly adjusted ones. I'm going to back them all off and re-torque them to spec (14lb + 30 deg), and see if that helps. If it does then I got a steal, if it doesn't then it may be time for some lifters and push rods. Any other ideas?
Any one near Austin, Texas?

Is it really only 14lbs? I thought it was more then that? But you could be right. Just seems low for that.

Torque specs
 

Yes, but remember 14 ft lbs = 168 in lbs, this may be why alot of people strip the bolts, as 168 ft lbs is surely to break something. here is a link http://extraconversion.com/energy/fo...ch-pounds.html to a conversion from ft to in lbs, and according to olds forum here http://oldsmobileforum.com/forum/showthread.php?t=1826 it should be 14 ft lbs or 168 in lbs + 30 degrees. :coolio:

Okay yeah, i remember the 168 number. But good clarification.


Id say re torque them all, and hope for the best. Will be your cheapest, easiest job.

If a rocker bolt has backed off or is pulled it will do exactly this and is quite common on the 3400. If you find one that is stripped, don't freak out too bad, if you heli-coil it you'll have no problem at all. I had one in mine and it still took 7k shifts with no issues at all, it never backed off again. If you have it all apart then make sure you use blue locktite on every bolt

Update
 

Thanks MMGT1, I'm trying to get my hands on a torque wrench asap, and in the meantime I ran some Marvel Mystery Oil through it, ran it for a few minutes each day for 2 days, and then changed the oil. Miraculously most of the noise is gone, and it is oiling on each rocker now, like it should. For those that say Marvel doesn't do anything, let this stand as a testament to it.

I'll post a vid of it soon so you can see the before and after. It really did clean out something, and I could see it washing out in the new oil, on top of the rockers. Looks like carbon deposits in the lifters or push rods coming out.

Most of the noise is gone, and it's slinging 5w30 everywhere now. I'm still going to check the rocker studs, and I think that will take care of the remaining occasional noise.

After treatment
 

Before treatment:

http://youtu.be/ehdAgC6vUl8

After Treatment:

http://youtu.be/F5hLJFJXrWo

Now the noise is only present at lower rpm's, higher rpms sound great. Now I just need to tweak the rockers and I think all will be good in the world.

Now I just need a torque wrench. Dammit.

Rent one from autozone.

Or buy one from Autozone. Never a bad thing to have.

Yea I've checked all the box stores around, they are either rented out or they want 100 bucks. I can order one from Summit Racing for 30.

Update
 

I torqued the front rockers to spec and almost all of the noise is gone, but when I got to the back side-horror story. Just as I feared #3 rocker was laying in there near #1, and the one beside it was working loose. BINGO-here is the culprit. But oddly the push rods for these two rockers are just not there, I believe the last "mechanic" that worked on it at his "shop" decided to just leave them out when he stripped the rocker bolts, then called the owner and said here's your car.

I don't understand how it was running so smooth at higher rpm and not making worse noise. In fact, I don't even see how it is possible that the engine is still alive, but it is. I'll post some pics shortly, I have the upper manifold off and I'm working down to the lower now. Is it possible to re-use the lower manifold gaskets since it just had heads put on it a few months ago? What about the bolts, aren't they single use? 80$ for the gaskets without the bolts. :eek: Jeez.

subscribed!

Sorry, no. Cant reuse gaskets no matter how little time they have been on. I myself, reused my LIM bolts when i got my ported manifolds, just throw some thread locker on em.

Threadlocker on the heli coils?
 

Thanks sleepy, should I use the blue thread locker on the heli coils too?

Pics pics pics!

Uhh i guess it couldnt hurt.

Heli-coils
 

Just a note for those adventurous souls who decide to take this road. It looks like there is not enough clearance to turn the heli-coil wrench without removing the lower intake. Someone please correct me if I am wrong.