This is an odd situation, I don't know if I have 2 seperate issues or what but here's the scenario. I have an sbc 350/th350 combo in my 63 chevy truck, a couple months ago I heard this intermittent ticking noise at idle and it was running a little rough and came to the conclusion that I had a lifter on it's way out so I put a new set of lifters in it and the noise went away. Now a couple months later the noise is back and it's worse, there is also a rattling sound, as if there was a pushrod rattling around under a loose tappet, at about 2000 rpm between second and third gear. I readjusted the valves but the noise is still there. I drove about 10 or 15 miles round trip on sunday, it was cold, near freezing with little noise and no other problems. I parked it and didn't drive it until tuesday afternoon, it was below freezing, I warmed it up didn't hear any noise at all but when I put it into drive it wouldn't move so I tried first and second, nothing, then reverse, still nothing. After holding the brake down with the truck in drive and reving the engine to about 2500 rpm the trans finally grabbed so I figured it was just cold. I drove about 3 blocks, stopped at an intersection and when I tried to go, the engine just reved and I sat there. I checked the ****** fluid and it registered full, all va***e lines are connected, I put it in reverse and reved it up and after a minute or two it grabbed and I figured I better get it home and park it so I backed into a driveway to turn around and when I put it in drive again, it was like I was in neutral so I pushed it home, parked it and there it sits. I searched the forum and found a post that said the noise I am hearing could be related to the torque converter. Did it go out, or is this a ****** issue, or two seperate problems? I know my way around the engine pretty well but don't know much about transmissions, any info is helpfull though.
did you look to make sure the engine and transmission are bolted tightly together? if the bolts that hold the trans to the block get loose, all kinds of fun things can happen. Also did you check to see that all the valves are opening all the way? It is quite possible that you have two problems here.
I'd guess it's a pump issue. Check in the pan to see if the filter has fallen off. , it's held on by two flat slot screws. It's no uncommon for that to happen. If the filter is on then when it's cold check the fluid BEFORE you start it. if the level is real high I mean way up on the stick, the converter drain back valve is stuck and the converter is emptying into the pan. That can be fixed by dropping the valve body. Check those and PM me back. We can fix it
I had a 350 that had what I thought was a lifter tick but turned out to be the timing chain slapping the cover.
Thanks onlychevs, I'm at work right now so I'll check those things when I get home in a few hours and get back to you.
I think Jim is concerned the cam may be going flat. Best way to check would be with a dial indicator, but a visual with the motor running and the valve cover off can spot it in an advanced state. What did the bottom of the lifters look like?
The bottom of the lifters were smooth and flat on the bottom, they all looked the same, no notable differences in apperance and all plungers were up. I got the engine from my boss and he said he thought he had a flat cam at 99,000 miles and rebuilt the whole engine and put 10:1 pistons, an RV cam and a bunch of other stuff in it and it has about 40,000 miles since the rebuild. He recomended putting a Z28 cam in it.
2 Seperate issues First is your cam is going round. You just can't change lifters on a chevy cam, the hardness situation is too marginal to start with. It was probably on it's way out before and now it's really on it's way out due to the new lifters. Pull the valve cover on the ticking side, and start the engine. You'll probably see one or more valves that aren't moving as vigorously. Low lift equals a slow rocker arm. The other is your transmission needs a rebuild. Pump failure symptoms are right along the lines of your description, but it could also be a dozen other things that all need the same thing......a rebuild kit and a trained eye. If you ever get an automatic that suddenly needs revved to move, don't pull it out in the street. You're tearing up hard parts that don't come in the rebuild kit. Th350s are an easy rebuild so don't pay too much, and might even know somebody who can rebuild them. Exchange the torque converter for a "corvette" spec rebuild with a couple hundred extra stall speed, but avoid cheap aftermarket saturday night special converters. You have to spend over $300 to get anything with efficiency levels close to the factory converter, and a rebuilt factory coverter is under a hundred bucks. Tons of guys waste torque using sh*tty converters and never realize it. Good luck with the project
P.S. When you figure out what the problem was can you please post the solution. You know, to help the next guy.
My guess is the pump in the ****** went south for the winter but I would not hold any hope as to it comming back in the spring !!!
I agree with shifty it sounds like a cam problem. My buddy had a similar problem he took the cam out it was wasted and also broken. Pump failure sounds right as I had the exact same problem with a blazer I had.
When I worked at the transmission shop in the early 80s we had a stack of worn out TH350 pump cores about 6 feet high. That's just the pump side, not the cover.
MAC that was my issue as well....crazy rattling sound that was driving me crazy turned out to be a cracked flex plate. I never woulda guessed. But the ****** not grabbin' gears is not even close. Good luck
If the flexplate was cracked wouldnt you get a horrible vibration or at least more noticeable then before?
Sometimes the center will completely break out of your flexplate. It can spin and your car will go nowhere. Then all of a sudden it will catch and your car will go forward. My buddy and I broke the center out of his on his Nova. We had to limp home from a deserted country road that we were out doing acceleration tests on. The ticking sound is one of the first signs. It sounded like his cam is fine from his description. I've broken several flexplates and know the sound well. The motor in my 81 El Camino was a month old crate motor that was bought for "core" price from the local Chevy dealership where my brother worked. A farmer had bought the motor and installed it himself. A month later it developed what he thought was a rod knock. Disgusted he took it to the dealer and wanted them to put a new motor in it. When they figured out the problem they called him, and he said "Screw it, replace it anyway." So I have a real nice 350 and my Brother made $300 because nobody thought to check the flexplate. I've been wrong before, but it would have been a hell of a lot easier to check the flexplate before removing all of your lifters. 3 bolts, vs.....how many? PS I go ahead and buy a aftermarket flexplate anytime I'm already there, like changing a transmission or engine. Not to much money and saves you a lot of headaches later.
If the flexplate was broken wouldn't you hear a bunch of noise when trying to start or at the very least have some trouble starting? At any rate I would think you would be unable to start before you would completely lose lose function of the trans. It starts with no problem and the converter spins when in park with no noise so it seems to me the flexplate is probably not the problem. However I have noticed that the noises have gone away since losing trans function so it would seem that the two are connected somehow and that my cam is not likely the problem either. Hmmmmmm?
Like I said, I've been wrong before. I'm just trying to help. A cracked flexplate sounds a lot like a lifter making noise. If you truck was right here I'd get a couple of wrenches and look at it for you.
Flexplates don't make noises that could be confused as ticking lifters. At least not that I've ever heard, one might argue the individual tap is close but the frequency is nowhere similiar between the two when you see how they're connected to RPM. The same can be said with transmission failure noises. If the center was broke out of your flexplate so bad that you had to rev it to 2500 to grab (as described) the noises could be heard on the moon. Pretty safe to rule that out. Anything broken inside the converter = transmission rebuild because it ingested garbage. Good luck and consider yourself lucky as you've got the worlds cheapest and most plentiful automatic. Removing one is not that bad if you just ATTACK!
The Stator side can be turned on a disc brake machine. But if the gear side is to loose...its time for a rebuilt one. I don't think its his pump. It could be the sprag in the converter let go. Either way its fixable...
I think I finally figured it out! The front pump went out so It's not circulating fluid. I ordered one today so I'll put it in this weekend. I"ll post the results in a few days.
The Jalopy Journal
