Maybe someone out there can help me. I have a 70 350 that has a knocking sound coming from the bottom of the engine. I can barely hear it from the top. It almost sounds like lifters knocking. the car had been parked for about 4 years when I bought it. I just dumped 1400 bucks in the trany and I can't afford a rebuild right now. Somebody please tell me it is normal for the small block to do this. o No:
Welcome Austin- ite There is an small group of buick owners that get together and help each other. a total of about 16 guys plus or minus as they come along. If you have any questions or would like to be added to or group email or PM me and I will give you a ring and bench race a little. What part of austin are you from? let me know if you are intrested.
My 350 is quiet as a mouse. It's the 10.5:1 compression 1969 vintage. When I first got it, I ran regular gas, like the previous owner. As soon as you'd put the car under any type of acceleration/load/hill it would knock wildly. I run nothing but 93 octane or higher, and it runs flawlessly. If your knock is not an octane or timing problem, I'm not sure that I can say it's anything good. Matt Gartman '69 Lesabre 400
Take the inspection cover down off the bottom of the transmission, and check the torque converter to flywheel bolts and the flywheel itself for cracks. This problem is more common than you think. At idle, loose bolts will sound like a knock, and when you put it in gear with your foot on the brake, it sounds like a tick. Check the easy things first. Good luck.
I'd also like to ask how on this earth you spent 1400 on the transmission? Through Jeg's high performance you can get a completely rebuilt/ready for the street/strip B&M Turbo 400 transmission w/ shipping for under 1000 clams. Anyhow, after the car has been sitting for that long, it's possible that you'd be noticing the carbon build up on the valves. You can give it a cheap "steamclean" by SLOWLY trickling a cup of water down the carb when the car is at operating temps. WARNING!!!! too much water at one time can cause a cylinder to hydrolock... and then you'll bend a lot of stuff. Otherwise I think you are dealing with a spun bearing. Possibly from oil starvation.
I'm with larry on this one as the same thing happened to me just a couple of years ago. I was all freaked out because it sounded just like a spun bearing. larry is right, it is a very common problem to have one or two loose converter bolts and have it sound like a spun bearing. you might try some octane booster and see if that eliminates the knock. if that doesn't work , drop the inspection cover on the tranny and try that next, or vise-versa.
found the problem guys. some genius before me had used the wrong dipstick. lack of oil. if i find the idiot again i am going to beat on his head. good thing i don't race the car.
