Beretta.net

my dad has a 3400 grand am gt. its a 2001, ran out of oil a while ago due to failure of the opsu. if you havnt changed this, i would.. anyways, fixed it, put oil in it, ran fine after that.. now it has a slight tick, you rev it, the tick gets lauder and you can feel the vibrating if you put your palm on the manifold. now, my question is, anyone have any suggestions as to what this tick might be, and do you think i could fix it with out replacing the motor, i.e. rocker arms, push rods, ect. im no expert on the v6, in fact, i dont tend to do much at all with one and never tore into one, but if i can fix it for my old man, it would be great and a lot cheaper then trying to put an engine in the car. any help appreciated. thanks.

running out of oil is bad. it could be a host of problems. it wouldnt be a bad idea to take the pushrods out to see if any are worn or bent.

If it ran out of oil, its probably got a rod knock... simple as that.

Does it sound like its coming from the bottom end? Or does it sound like its coming from the valley? Is it a tick? Or a knock?

It could be a lifter not pumping up.

Use a mechanics stethoscope and check along each valve cover. You should be able to tell which cylinder is noisy.

its deffinetly coming from up top. and its just a tick, not a knock. just a tick, if you rev it, it chatters... doesnt sound like a rod knock, but idk, is it hard to replace the rods? and do you think it could fix the problem?

It isn't rods if its coming from up top. It's probably a lifter. Use the scope to figure out which cylinder, or at least which bank it is. Then pull off the valve cover and check each pushrod while turning the engine over by hand. When a cylinder is at TDC, both valves should be closed so check if one of the pushrods are loose. Also try pushing down on them, you will get a feel for how it should be. If one is really easy to push down, there's your problem.

Hmm, okay, so I see this was posted after the request for info on changing out the engine altogether, so hopefully that implies the engine is salvageable. I did bearings on my '90 turbo 'Retta a few years ago after the first time I swapped the 3400 block into it while the engine was still in the car, but it is a five-speed car which makes getting to the oil-pan bolts much easier. I also swapped out two of the piston/rod assemblies on my old '95 Z-26 when I first got it, without removing the engine from the car (obviously I had to pull both heads, but they were bad and had to be pulled anyway -the engine had been overheated so badly that the valve-guides had actually dropped out of the heads! That is how I bought the car...), with the oil-pan side-support bolts blocked in the back by the auto tranny, it was a PITA, but still better than pulling the whole engine out of the car in a gravel driveway in the dead of winter... Ahh, good times.

In short, swapping out rods on a 3400 without pulling the engine is doable, I'm not sure if the subframe on the GA would get in the way of pulling the pan or not, but getting the pan off and back on is the hardest part of the job. Once off, you can inspect the bottom-end to determine if the crank is toast (pull the engine in that case), remember to use plasti-gauge once new bearings are installed to be certain the crank is still within spec, and try to get a caliper or micrometer in on the journals to make certain they are still round. Pulling the engine and rebuilding the bottom-end might be easier if you are uncomfortable working under the car, but otherwise it is just preference, and saves the hassle of pulling the engine.

Just to offer my 2-cents here, a flat lifter won't cause much in the way of vibration, so I'm betting on rod bearings, particularly since GM started using aluminum bearings instead of babbit or tri-metal types, cheap sons of...