The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - 47-55.1 What's going wrong inside my 350?

NeoJuice · 01-06-2019, 12:13 AM

Ok update time folks. I hired a local Mobile mechanic here where I live. He charged me $90/hour to come look at the truck. I didn't want to spend the money but I needed professional opinion.

We spent an hour going over the truck. He checked the starter bendix and it is disengaging when the motor is running. He checked the flex pate and torque converter and the bolts on the flex plate. Everything appeared to be working as it should and no rubbing marks or anything was found.

He then started to do some investigation further using his stethoscope and start pointing it all over the motor top and bottom. He said the noise is coming from behind the timing cover. So now I know that something is f*cked up with the timing chains/gears.

I mentioned to him that when the truck came back from the exhaust shop that the motor did make a couple loud ping noises and I wasn't sure what it was. I told him I thought it might have been the starter skipping a tooth on the flex plate or something like that and that's when the noise started.

So now I think I have a place to start. I'll have to pull the rad out. Drain all the fluids. Pull the water pump off and harmonic balancer and see what is going on behind the timing cover. I'll also have to rent or buy a puller to get that balancer off.

What I'm going to find behind the timing cover? I don't know and what parts will need replaced. Ill also see maybe if it needs a new harmonic balancer as well depending on the shape its in. The mechanic said probably not, but he's only seen maybe a handful needing replaced on 350s over the 20+ years he's been a mechanic.

He said it could have broken a tooth off. One of the bolts could have come loose or something like that and parts could be flying around on the inside of the cover causing all the noise. Now this could be a possibility because the previous owner said he put a mild cam in the engine, so at some point the engine must have been apart. Also because of the chrome timing chain cover.

So if you have any idea what I might find broken behind the cover please pass me on your thoughts.

01-06-2019, 12:13 AM	#61
NeoJuice Registered User Join Date: Nov 2016 Location: Beaumont, Alberta Posts: 468	Re: What's going wrong inside my 350? Ok update time folks. I hired a local Mobile mechanic here where I live. He charged me $90/hour to come look at the truck. I didn't want to spend the money but I needed professional opinion. We spent an hour going over the truck. He checked the starter bendix and it is disengaging when the motor is running. He checked the flex pate and torque converter and the bolts on the flex plate. Everything appeared to be working as it should and no rubbing marks or anything was found. He then started to do some investigation further using his stethoscope and start pointing it all over the motor top and bottom. He said the noise is coming from behind the timing cover. So now I know that something is f*cked up with the timing chains/gears. I mentioned to him that when the truck came back from the exhaust shop that the motor did make a couple loud ping noises and I wasn't sure what it was. I told him I thought it might have been the starter skipping a tooth on the flex plate or something like that and that's when the noise started. So now I think I have a place to start. I'll have to pull the rad out. Drain all the fluids. Pull the water pump off and harmonic balancer and see what is going on behind the timing cover. I'll also have to rent or buy a puller to get that balancer off. What I'm going to find behind the timing cover? I don't know and what parts will need replaced. Ill also see maybe if it needs a new harmonic balancer as well depending on the shape its in. The mechanic said probably not, but he's only seen maybe a handful needing replaced on 350s over the 20+ years he's been a mechanic. He said it could have broken a tooth off. One of the bolts could have come loose or something like that and parts could be flying around on the inside of the cover causing all the noise. Now this could be a possibility because the previous owner said he put a mild cam in the engine, so at some point the engine must have been apart. Also because of the chrome timing chain cover. So if you have any idea what I might find broken behind the cover please pass me on your thoughts.