47-55.1 What's going wrong inside my 350?

[NeoJuice]

Originally Posted by 1project2many

dsraven's suggestion to cut the oil filter open has merit. I haven't ever heard a noise that loud from oil flow through a bypass valve but I'll keep an open mind. Thinking back, that noise is vaguely familiar but I can't place it. I have heard a dry rear main seal make noise like that but IIRC that was a one piece rear main, not the two piece you're running now. I suppose a tight set of rings could make a noise and potentially so could a thrust bearing that is too tight fore and aft.

I'm waiting patiently to see how this turns out.

The truck engine is a 78 which should have a two piece rear main seal.

[dieseldude4bt]

sounds like a spun bearing. Pull pan and have a look.

[weim55]

But yea, while I'm careful with audio from a video, that certainly sounds external to me. List off the top of head in priority:

Starter bendix engaged

Flywheel to crank bolts too long

Flywheel rubbing-hitting something (carefully turn and look for witness marks)

Too long crank pulley bolts hitting timing cover

Timing chain hitting- rubbing timing cover

Fuel pump arm hitting the timing chain

Steve weim55 Colorado

[NeoJuice]

Originally Posted by weim55

But yea, while I'm careful with audio from a video, that certainly sounds external to me. List off the top of head in priority:

Starter bendix engaged

Flywheel to crank bolts too long

Flywheel rubbing-hitting something (carefully turn and look for witness marks)

Too long crank pulley bolts hitting timing cover

Timing chain hitting- rubbing timing cover

Fuel pump arm hitting the timing chain

Steve weim55 Colorado

Thanks for the suggestions. I hope to have an update soon for everyone.

[dsraven]

if you pull the filter and find bad news it would be in your best interest to pull the engine out and completely disassemble the engine and see what you have. I have seen some guy's idea of a rebuilt. some are a car wash and some engine paint. some are dissassemble, ball hone,, rering and bearing and assemble without even checking ring end gap or bearing clearances. some are a complete, properly checked, cleaned, spec'd rebuilt like you would expect when told it is redone. I installed an engine for a fiend who had a reputable engine builder do his 350 into a 383. it arrived all nice and fresh looking. when I poured coolant in there was a leak right away at the rear somewhere. turned out the frost plugs weren't even replaced let alone the block hot tanked. there was a whole load of problems with the engine including stripped bolt holes, leaky seals etc. best to take it apart and see for yourself if it comes to that. hopefully it is something simple and you can carry on.
I have found it is best to see the bills for the work or else make the deal as if the engine were an old clunker. unless the guy has bills for new parts and actual specs for clearances, work done etc, you just can't tell. some guys honestly believe what they have done constitutes a "rebuilt" engine. one easy way to tell if it has at least had some work is with a boroscope through a spark plug hole and through the oil filler to see what that part looks like.
anyway, hopefully it is an easy fix and it doesn't keep you up at night.
keep us posted

[NeoJuice]

Originally Posted by dieseldude4bt

sounds like a spun bearing. Pull pan and have a look.

I'm hoping not to have to pull the pan yet until I have a chance to figure out the other issues. If it's a spun bearing this is going to put a major blow to my budget and timeline to try get the truck on the road this year.

Also if it is.......... I'm going to ring the guys neck who sold me the truck. I'm keeping my fingers crossed and my temper in check for now.

[1project2many]

After getting the motor and pulling off the intake manifold the insides and the water jackets were gummed up with crud. So was it rebuilt?

No. That kind of crud takes years to accumulate.

Could the build up in the engine because it sat for such a long time with dexcool in it instead of antifreeze?

No. Dexcool is antifreeze. It has a different additive package but it still resists corrosion. That type of buildup requires many heat cycles to develop.

[NeoJuice]

Here are some old pictures I took back on 4-1-2017 when I ripped the manifold off.

[DransportGarage]

Originally Posted by NeoJuice

Here are some old pictures I took back on 4-1-2017 when I ripped the manifold off.

The pictures don't really show any crud, through it might be there. That's promising for you, because that engine may have been rebuilt a few hunderd miles ago.

I bought a Cutlass about 5 years ago. It came with two engines. The original was out and a "newly rebuilt" one was in it. I sold the "newly rebuilt" one on Craigslist. When the guy came to buy it, he asked if we could take a valve cover off. I said sure. Was I embarrassed! We could hardly see the rockers. I cut the price in half and he took it anyway. Unbelievably, we're good friends today.

[1project2many]

Thanks for posting.

Here's what a clean coolant passage looks like:


Look at rightmost port on rear head to see "normal accumulation of deposits":


This is what "gummed up with crud" looks like.

[NeoJuice]

Originally Posted by 1project2many

Thanks for posting.

Here's what a clean coolant passage looks like:


Look at rightmost port on rear head to see "normal accumulation of deposits":


This is what "gummed up with crud" looks like.

My ports did definitely not look like the crud pictures you posted. Thanks for the clarification.

Wow I guess you did luck out on that 'newly rebuilt' one in the Cutless. Under my valve covers was pretty clean and no build up at all with all clean passages.

I hope to have some answers tomorrow and more pictures. I was hoping to get out to the garage tonight but the wife had other chores for me to do.

[GreasyLikeaBurger]

That coolant looks like inter mixing of two different types of coolant. I have seen it on some VAG coolant when it is mixed with store bought green stuff.

[1project2many]

Originally Posted by GreasyLikeaBurger

That coolant looks like inter mixing of two different types of coolant. I have seen it on some VAG coolant when it is mixed with store bought green stuff.

Good eye! That's exactly what happened. The picture was taken from a thread on an antique car forum. The vehicle owner was sold Dex-cool by a parts chain zombie and found after a year or two that the two additive packages do not play well together.

ps. By VAG i mean the pink stuff VW, Audi, Porsche and every other manufacturer under the VW umbrella uses.

LOL. A young man in this state worked hard to convinced the state censors to allow a vanity plate for his highly modified Audi that reads "LV-VAG." He even wore a T-shirt to the hearing that read something like I heart VAG.

[NeoJuice]

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.

[DransportGarage]

Originally Posted by NeoJuice

<snip>

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

I really hate to be the bearer of bad news, but...

My guess is, the same brain surgeon that forgot the converter bolts didn't tighten the three timing sprocket bolts...and you can assume he's the same guy that did the rest of the engine. It's time for a full engine disassembly and inspection. At a minimum you'll be finding circular score marks on the inside of the timing chain cover, or something similar. To make yourself feel better about all of the work, check the torque specs on the bolts. They're probably all over the place. Leave the heads together, don't take the pistons off of the rods and leave the freeze plugs in unless you find something screwy or you decide to have the castings hot-tanked.

There's plenty of YouTube on the assembly (e.g., https://www.youtube.com/watch?v=UmIslf3ANTs), but if you're not comfortable with this level of work, do the disassembly yourself. Keep track of the location of EVERY push rod, lifter, piston, etc. Clean everything, then buy some steaks and invite a knowledgeable friend over for a Saturday of fun. Keep the beer in the fridge until your done. (Man, I wish I lived closer. I like mine medium-rare...)

Don't rent the tools until you find out what your friend will bring. Then go to AutoZone and they will lend you most of what you need for free.

[Driver_WT]

Originally Posted by DransportGarage

I really hate to be the bearer of bad news, but...

My guess is, the same brain surgeon that forgot the converter bolts didn't tighten the three timing sprocket bolts...and you can assume he's the same guy that did the rest of the engine. It's time for a full engine disassembly and inspection. At a minimum you'll be finding circular score marks on the inside of the timing chain cover, or something similar. To make yourself feel better about all of the work, check the torque specs on the bolts. They're probably all over the place. Leave the heads together, don't take the pistons off of the rods and leave the freeze plugs in unless you find something screwy or you decide to have the castings hot-tanked.

There's plenty of YouTube on the assembly (e.g., https://www.youtube.com/watch?v=UmIslf3ANTs), but if you're not comfortable with this level of work, do the disassembly yourself. Keep track of the location of EVERY push rod, lifter, piston, etc. Clean everything, then buy some steaks and invite a knowledgeable friend over for a Saturday of fun. Keep the beer in the fridge until your done. (Man, I wish I lived closer. I like mine medium-rare...)

Don't rent the tools until you find out what your friend will bring. Then go to AutoZone and they will lend you most of what you need for free.

Great advice. If you find two things that were not done right, there are bound to be many more. And if for nothing else, it will provide peace of mind and confidence that you know what you have after the engine has been gone through.

[NeoJuice]

Originally Posted by DransportGarage

I really hate to be the bearer of bad news, but...

My guess is, the same brain surgeon that forgot the converter bolts didn't tighten the three timing sprocket bolts...and you can assume he's the same guy that did the rest of the engine. It's time for a full engine disassembly and inspection. At a minimum you'll be finding circular score marks on the inside of the timing chain cover, or something similar. To make yourself feel better about all of the work, check the torque specs on the bolts. They're probably all over the place. Leave the heads together, don't take the pistons off of the rods and leave the freeze plugs in unless you find something screwy or you decide to have the castings hot-tanked.

There's plenty of YouTube on the assembly (e.g., https://www.youtube.com/watch?v=UmIslf3ANTs), but if you're not comfortable with this level of work, do the disassembly yourself. Keep track of the location of EVERY push rod, lifter, piston, etc. Clean everything, then buy some steaks and invite a knowledgeable friend over for a Saturday of fun. Keep the beer in the fridge until your done. (Man, I wish I lived closer. I like mine medium-rare...)

Don't rent the tools until you find out what your friend will bring. Then go to AutoZone and they will lend you most of what you need for free.

Thanks for the video link. I'll be doing my research before I start to rip things apart. I'm still contemplating on what to do with the engine. I still have the guys phone number I bought the truck from. I was thinking of giving him a call to discuss the situation. But its not like he would be honest with me this time right since he already got his money. But it might be a little beneficial to hopefully get some more information out of him if he would be entirely honest this time. If I have to junk the block then it's junk. If it was truly rebuilt then there should be no problem right?

Hell if all it takes is some cold beer and steaks your a mighty good neighbor. I'm firing up the bbq now lol.

[GreasyLikeaBurger]

ps. By VAG i mean the pink stuff VW, Audi, Porsche and every other manufacturer under the VW umbrella uses.

[mongocanfly]

hmmmmmm....I do believe if it were mine the engine would come out and id go thru it completely...a SB is the cheapest engine to rebuild anyway...

[Volfandt]

The sound definitely gets louder as you moved the cam towards the front and based on what your mechanic said about isolating it to under the timing cover, I would be pulling that water pump and balance and removing that timing cover for a look see. If nothing was apparent I'd be dropping the oil pan in no uncertain terms. I wouldn't run it unnecessarily anymore as you will make a bad situation worse.
Thats metal on metal and that isn't a good sound on an ICE...
Get your wrenches out and start checking.

Good luck

[NeoJuice]

OK so hear is my update for tonight. I was able to get a hold of the previous owner of the truck via txt.

He told me that the truck has a Pete Jackson gear drive on the truck with a Edelbrock Part # 5002 Torker-Plus Camshaft. He said the cam might be to big for what I want to do with the truck. it might have a nice lope noise if it was tuned up properly.

https://www.edelbrock.com/torker-plu...0-v8-5002.html

https://www.summitracing.com/int/par...-91c/overview/

He said with the exhaust off the truck you would barely hear it but once the exhaust is on you hear it because it sounds like a damm super charger I explained to him. He said he wanted it to be loud and it definitely is.

So as my mechanic pointed the noise is definitely coming from behind the timing cover because its a damm gear drive.

Now that question is do I tear it off for a double roller timing chain? This gear drive totally over powers the entire sound of the truck since I just had dynomax super turbos put on the exhaust.

What are your thoughts. Do I get the timing/carb tuned up with this timing gear in the truck or pull it out? I mean once the truck it tuned up it might not be to bad. But I definitely dont want something that bloody loud. It would be like a real bad exhaust drowning noise in the cab except it's the timing gear cruising down the road at 70mph.

Examples:
https://www.youtube.com/watch?v=MATs3uYyD3c
https://youtu.be/s8Yd03mvSjM?t=51
https://www.youtube.com/watch?v=WybQuVxS-Sg
https://www.youtube.com/watch?v=UFKS_qws-_w
https://www.youtube.com/watch?v=7IYrJO0si5I

[Jason 56]

Just get a new timing chain set as you mentioned. They’re inexpensive. It’s really easy to change and the current setup isn’t what you want. Do like DSRaven said and pull the alignment pins in the cover so you don’t have to remove the pan. Align the timing marks on the gears before you remove them and replace. Make sure to put lock tight blue on the 3 cam bolt. You don’t want those coming loose.

[dsraven]

that's what I was referring to in post 35, about trying to find out what is inside the engine. I have heard a noisy gear drive timing set, they are noisier than a blower from the '70's. it would get annoying pretty quickly.
if I were you I would drag that gear drive out of there and install a quality timing gear set. maybe even change the cam if you want but then there is valve train and lifters to deal with as well so more work to do. you could simply drive it like it is and fix that later. you still should get it running properly so it at least idles.

[NeoJuice]

Originally Posted by dsraven

that's what I was referring to in post 35, about trying to find out what is inside the engine. I have heard a noisy gear drive timing set, they are noisier than a blower from the '70's. it would get annoying pretty quickly.
if I were you I would drag that gear drive out of there and install a quality timing gear set. maybe even change the cam if you want but then there is valve train and lifters to deal with as well so more work to do. you could simply drive it like it is and fix that later. you still should get it running properly so it at least idles.

I was just talking to my buddy about it and he said to pull that timing gear off and put a good double roller on there instead. I don't want my truck to sound like that since i just put a new exhaust on it with dynomax super turbos. I've lined up a good contact to do the timing & carb tuning but that will now be delayed until I can get this cam gear swapped out.

[DransportGarage]

Originally Posted by jason 56

just get a new timing chain set as you mentioned. They’re inexpensive. It’s really easy to change and the current setup isn’t what you want. Do like dsraven said and pull the alignment pins in the cover so you don’t have to remove the pan. Align the timing marks on the gears before you remove them and replace. Make sure to put lock tight blue on the 3 cam bolt. You don’t want those coming loose.

Originally Posted by dsraven

that's what i was referring to in post 35, about trying to find out what is inside the engine. I have heard a noisy gear drive timing set, they are noisier than a blower from the '70's. It would get annoying pretty quickly.
If i were you i would drag that gear drive out of there and install a quality timing gear set. Maybe even change the cam if you want but then there is valve train and lifters to deal with as well so more work to do. You could simply drive it like it is and fix that later. You still should get it running properly so it at least idles.

x2 x2. Besides, I still think there's a metal-to-metal interference thing going on. Chances are, the gear drive install may not be right.