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

[NeoJuice]

Originally Posted by whitedog76

When I say front pump, I mean transmission pump. The pump on the 700R4 has small tabs inserted into a disc that rotatates in an oblong fashion. If the transmission wasn't assembled properly, clearances checked, etc... You can have metal on metal, sqealing etc... If the torque converter wasn't seated properly, and the bellhousing bolted down, you can actually damage the pump, and torque convertor.

You stated that the flex plate wasn't bolted up initially, which is why I'm leaning to the transmission side of things.

Unfortunately, the only way to know is to start pulling things apart.

Chris

the torque converter was missing the bolts to the flex plate.

[Black_Sheep]

Originally Posted by whitedog76

The high pitch squeal on the you-tube video is concerning, sounds like a spun bearing, or some sort of metal on metal.

The flex-plate video, I didnt' hear the squeal, but sounded like the starter hanging up.

1) I know there were some alignment issues with GM starters.

2) I've seen the center broken out or flex-plates. Everything appeared normal until dis-assembled.

3) Did the torque convertor get seated properly? May be an issue with your front pump.

It sounds like metal to metal to me too. Pull the plugs and rotate the crank by hand, without the engine running it should be easier to hear where the sound is coming from.

[joedoh]

hi, sorry if this has been asked or answered, you said the torque converter wasnt bolted to the flex plate, but what if it was? loosely, I mean. did you find any bolts in there, like something that came loose and fell out?

to me, the video sounds like metal on metal squealing, like a bolt got stuck behind the flex plate.

[NeoJuice]

Originally Posted by joedoh

hi, sorry if this has been asked or answered, you said the torque converter wasnt bolted to the flex plate, but what if it was? loosely, I mean. did you find any bolts in there, like something that came loose and fell out?

to me, the video sounds like metal on metal squealing, like a bolt got stuck behind the flex plate.

There were no bolts in the torque converter at all. I had to go buy three new ones. I'm going to crawl under the truck tonight and do one more inspection but the mechanic said everything looked to be in order.

[NeoJuice]

Originally Posted by Black_Sheep

It sounds like metal to metal to me too. Pull the plugs and rotate the crank by hand, without the engine running it should be easier to hear where the sound is coming from.

I will give this a try to see if I can hear what might be going on inside the motor. If it makes it easier to turn over by hand I'll defiantly give it a shot.

[Henry50]

Unbolt the torque converter pull it back away from the flexplate and restart it.

I bet the converter wasn't seated properly.

[NeoJuice]

Originally Posted by Henry50

Unbolt the torque converter pull it back away from the flexplate and restart it.

I bet the converter wasn't seated properly.

The sound was there before I bolted the torque convert to the flex plate. Since the truck sat for such a long time I assumed that the torque converter might have rusted itself to the flex plate then finally broke free after starting the truck multiple times.

I figured the sound would have been from the torque converter snout rubbing up against the flex plate but that wasn't the case after bolting them together.

[Softpatch]

Originally Posted by henry50

unbolt the torque converter pull it back away from the flexplate and restart it.

I bet the converter wasn't seated properly.

.
.....bingo.!
.

[NeoJuice]

Originally Posted by Softpatch

.
.....bingo.!
.

This is not the answer to the problem. The noise was happening before I bolted the converter to the flex plate. I should have an update in the next couple days once I have a chance to look at it closer.

[dsraven]

pull that oil filter, cut it apart and have a look see of whats in it and also look behind it (that adapter with the check valve that may be whistling as oil is bypassing). if you find filings in the filter element then you KNOW it's internal and need to stop running the engine since that will cause more damage. that is the quickest and easiest thing to check and causes no more damage if there is an internal issue.
do you have any specs on whats inside the engine? anything different from a stock 350, windage trays, high volume oil pump (which may require a high flow filter) or special timing gear set up etc? have you tried simply swapping the oil filter or listening directly AT the oil filter? some filters have an anti drain back valve built in and this could also be "whistling" as oil goes through it,theoretically. it would be worth a listen maybe. are you sure the oil filter is the correct one for the engine? some filters have the same dimensional size and thread but are made to flow opposite of other filters, so from the inside to the outside or opposite to what a standard 350 would flow. if you have the wrong filter and the filter has an anti drain back valve, then the valve could be fluttering causing the noise or the filter could be bypassing due to low flow through the filter because the filter isn't made to flow the wrong way. you say there was lots of oil flow when you primed the engine but if the system is bypassing it may still have good flow but the oil will not be filtered properly. the bypass is built into the oil filter adapter and is made to open if there is low flow through the filter from cold, thick oil or the filter were to plug up (or you simply have the wrong filter). if a high flow oil pump were used or the builder changed the pressure relief valve setting in the oil pump, then a high flow oil filter may be required. these typically are for race engines where the owners sacrifice filtering for flow.
is there a reason why the engine won't stay running/idling by itself and needs to be babysat? possible cause of the noise as well?
from memory, does the noise increase exactly with engine rpm or stay the same pretty well or only a slight difference with an rpm change? if something were rubbing on a rotating part then it would change exactly as the rpm changes. if the noise is something like, say, a vacuum leak then it would change with rpm but not necessarily be exactly as the rpm changes, if you get my drift?
here is a little video on the oil filter system

https://www.onallcylinders.com/2016/...filter-bypass/

here is a video or 2 showing the filter cut away so you can see the anti drain back valves and what the filters look like inside. some filters have cardboard end caps instead of steel so they would be the lesser quality ones, in my mind.

https://www.youtube.com/watch?v=HXGHA8DUhGQ

https://www.youtube.com/watch?v=X3JulJDNpeU

https://www.youtube.com/watch?v=lrAbxCZlZpE

[NeoJuice]

Originally Posted by dsraven

pull that oil filter, cut it apart and have a look see of whats in it and also look behind it (that adapter with the check valve that may be whistling as oil is bypassing). if you find filings in the filter element then you KNOW it's internal and need to stop running the engine since that will cause more damage. that is the quickest and easiest thing to check and causes no more damage if there is an internal issue.

do you have any specs on whats inside the engine? anything different from a stock 350, windage trays, high volume oil pump (which may require a high flow filter) or special timing gear set up etc? have you tried simply swapping the oil filter or listening directly AT the oil filter? some filters have an anti drain back valve built in and this could also be "whistling" as oil goes through it,theoretically. it would be worth a listen maybe. are you sure the oil filter is the correct one for the engine? some filters have the same dimensional size and thread but are made to flow opposite of other filters, so from the inside to the outside or opposite to what a standard 350 would flow. if you have the wrong filter and the filter has an anti drain back valve, then the valve could be fluttering causing the noise or the filter could be bypassing due to low flow through the filter because the filter isn't made to flow the wrong way. you say there was lots of oil flow when you primed the engine but if the system is bypassing it may still have good flow but the oil will not be filtered properly. the bypass is built into the oil filter adapter and is made to open if there is low flow through the filter from cold, thick oil or the filter were to plug up (or you simply have the wrong filter). if a high flow oil pump were used or the builder changed the pressure relief valve setting in the oil pump, then a high flow oil filter may be required. these typically are for race engines where the owners sacrifice filtering for flow.
is there a reason why the engine won't stay running/idling by itself and needs to be babysat? possible cause of the noise as well?
from memory, does the noise increase exactly with engine rpm or stay the same pretty well or only a slight difference with an rpm change? if something were rubbing on a rotating part then it would change exactly as the rpm changes. if the noise is something like, say, a vacuum leak then it would change with rpm but not necessarily be exactly as the rpm changes, if you get my drift?
here is a little video on the oil filter system

https://www.onallcylinders.com/2016/...filter-bypass/

here is a video or 2 showing the filter cut away so you can see the anti drain back valves and what the filters look like inside. some filters have cardboard end caps instead of steel so they would be the lesser quality ones, in my mind.

https://www.youtube.com/watch?v=HXGHA8DUhGQ

https://www.youtube.com/watch?v=X3JulJDNpeU

https://www.youtube.com/watch?v=lrAbxCZlZpE

Dsraven,

Thanks again for the tips. All I was told from the previous owner was "Fresh rebuilt Chevrolet 350 with .030" bore over and mild cam". 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? I dont know. Could the build up in the engine because it sat for such a long time with dexcool in it instead of antifreeze? Not sure.

I'll pull the oil filter off and see whats going on inside and replace it with a napa platinum filter.

The engine needs to be baby sat because the timing is not set and the carb needs tuned properly. When I got the truck i pulled off the tri-power manifold and old mallory distributor and replaced them with an edelbrock manifold and MSD distributor. I turned the motor by hand to get #1 to TDC and dropped in the distributor for initial timing. I also rebuild the carb with a kit and set it to what I would know would be default settings. So between both things being not set it needs a little babying.

The noise does appear to increase with RPM. I hope to have some time tonight or on the weekend to check the starter to see if it's binding up on idling. I will also see if I can get a look at the flex plate bolts and provide an update to everyone here.

[MD2020]

Originally Posted by Henry50

Unbolt the torque converter pull it back away from the flexplate and restart it.

I bet the converter wasn't seated properly.

x2

[NeoJuice]

Originally Posted by MD2020

x2

Before I put in the bolts into the flex plate for the torque converter I made sure to spin it towards the drivers side of the transmission to make sure that it was seated properly. Then after that I slide it forward maybe 1/8" so it would touch the flex plate to put the bolts in.

[mr48chev]

That probably wasn't an issue as he could turn the converter easily to line up the bolts when he put the flex plate to converter bolts in. At least he didn't say it was hard to turn.

Cracked or broken flex plate is usually a rattle or almost a knock that goes away when you put the trans in gear and put a slight load on it. I got a free engine that "had a knock" from one of those back years ago and drove that engine about 80K after that.

You can buy the mechanics stethoscope at O'Reilly's or Autozone for about 8 bucks if you don't have a HF close. The one I use now came from Autozone after one of the ear pieces came missing on my old one. I've done the broom handle thing, hose thing and what not but the stethoscope really works to isolate noises.

It made the noise when the converter wasn't connected so that rather eliminates the trans and converter. To be positive you could pull the three bolts out of the flex plate and slide the converter back in the trans with about a half inch clearance and fire up the engine again. If you already had that clearance before forget that step

You could raise the truck up and have a helper fire it up to see if the starter drive releases from the flexplate when it starts. You would have to remove the cover if you already put it on but that only takes a minute. You should see it pop back as soon as the engine fires up. I'm not sure if you could catch it by laying a phone or camera on video under it and aiming it up there but if you are working alone that might be worth a try. If it is a fresh from the parts house rebuilt starter a lot of rebuiders machine the mounting surface every time they go though the rebuild plant and after two or three go arounds over the years a lot of metal gets shaved off them. It may just need shims.

On old engines with a lot of miles on them I have seen a number of worn out timing chains that rubbed the timing cover with a couple of them wearing though the covers.

Like most other guys on here I am not a fan of Fram filters preferring either the Wix or a Napa Gold. Years ago Fram decided to put most of their money into advertising rather than producing the best filter they could and their filters are far from the best.

[NeoJuice]

Originally Posted by mr48chev

That probably wasn't an issue as he could turn the converter easily to line up the bolts when he put the flex plate to converter bolts in. At least he didn't say it was hard to turn.

Cracked or broken flex plate is usually a rattle or almost a knock that goes away when you put the trans in gear and put a slight load on it. I got a free engine that "had a knock" from one of those back years ago and drove that engine about 80K after that.

You can buy the mechanics stethoscope at O'Reilly's or Autozone for about 8 bucks if you don't have a HF close. The one I use now came from Autozone after one of the ear pieces came missing on my old one. I've done the broom handle thing, hose thing and what not but the stethoscope really works to isolate noises.

It made the noise when the converter wasn't connected so that rather eliminates the trans and converter. To be positive you could pull the three bolts out of the flex plate and slide the converter back in the trans with about a half inch clearance and fire up the engine again. If you already had that clearance before forget that step

You could raise the truck up and have a helper fire it up to see if the starter drive releases from the flexplate when it starts. You would have to remove the cover if you already put it on but that only takes a minute. You should see it pop back as soon as the engine fires up. I'm not sure if you could catch it by laying a phone or camera on video under it and aiming it up there but if you are working alone that might be worth a try. If it is a fresh from the parts house rebuilt starter a lot of rebuiders machine the mounting surface every time they go though the rebuild plant and after two or three go arounds over the years a lot of metal gets shaved off them. It may just need shims.

On old engines with a lot of miles on them I have seen a number of worn out timing chains that rubbed the timing cover with a couple of them wearing though the covers.

Like most other guys on here I am not a fan of Fram filters preferring either the Wix or a Napa Gold. Years ago Fram decided to put most of their money into advertising rather than producing the best filter they could and their filters are far from the best.

mr48chev,

I appreciate all your input. To answer some of your questions above.

-i wouldnt say the engine was to hard to turn but it took a little arm muscle to get it to move. I was using a 1/2" drive with 1 foot arm on it. Probably would have been easier if I used a longer wrench.

-yes it made the noise before the torque was bolted to the flex plate so that would eliminate the trans and converter. Yes I did have a small clearance before bolting them together.

-I will try to lay my phone down under the truck to get another video. I believe when i checked the starter (engine off), the starter drive(bendix) was back inside the starter.

Could the drive/bendix it get stuck in the out/startup position after starting the engine? then one stopped pull back into the starter?

[Jesse Z]

Originally Posted by FiftyTwo

If it were mine, I'd disconnect the torque converter, rotate and slide it in until it is engaged properly into the pump. Then start the engine while its disconnected from the flexplate and see if the noise is gone. I would want to eliminate the transmission as a problem and then move on to the next thing to eliminate.

Like the mechanic at work used to say about noises: "Let it develop." He knew you could spend countless hours tracking down noises, but if you let them alone they eventually made themselves obvious.

[mongocanfly]

Haha...I was just thinking of making a list of all the suggestions he's got so far....hopefully your issue will be a simple fix....

[NeoJuice]

Originally Posted by mongocanfly

Haha...I was just thinking of making a list of all the suggestions he's got so far....hopefully your issue will be a simple fix....

Me to. I mean I'm a fairly mechanically inclined guy but when it comes to internal motor stuff I have no clue and I appreciate everyone stepping up and giving me a hand. Now I just wish someone was a neighbor or close by to give me a hand lol.

[mongocanfly]

(Could the drive/bendix it get stuck in the out/startup position after starting the engine? then one stopped pull back into the starter? )
yes

[NeoJuice]

Originally Posted by mongocanfly

(Could the drive/bendix it get stuck in the out/startup position after starting the engine? then one stopped pull back into the starter? )
yes

Good to know.

[FiftyTwo]

Lots of good suggestions, but I'm leaning towards the torque converter/flexplate area. I thought the torque converter sure looked wobbly as it was running. I'd also like to see a close up picture of the torque converter bolts on the flexplate. Is the flexplate on backwards?

Also, no mention of transmission fluid in this thing. Does it even go into gear? You could also pull a transmission line and start it up and see if fluid is being pumped. No fluid-no transmission pump.

If it were mine, I'd disconnect the torque converter, rotate and slide it in until it is engaged properly into the pump. Then start the engine while its disconnected from the flexplate and see if the noise is gone. I would want to eliminate the transmission as a problem and then move on to the next thing to eliminate.

[NeoJuice]

Originally Posted by FiftyTwo

Lots of good suggestions, but I'm leaning towards the torque converter/flexplate area. I thought the torque converter sure looked wobbly as it was running. I'd also like to see a close up picture of the torque converter bolts on the flexplate. Is the flexplate on backwards?

Also, no mention of transmission fluid in this thing. Does it even go into gear? You could also pull a transmission line and start it up and see if fluid is being pumped. No fluid-no transmission pump.

If it were mine, I'd disconnect the torque converter, rotate and slide it in until it is engaged properly into the pump. Then start the engine while its disconnected from the flexplate and see if the noise is gone. I would want to eliminate the transmission as a problem and then move on to the next thing to eliminate.

I will get pictures of the flex plate and bolts as soon as I can. I know there is transmission fluid flowing into the transmission because after I got the exhaust done both my lines on the passengers side of the trans were pissing fluid. Once I got them tightened up no more leaks.

After I check for starter hang up on the flex plate I will remove the bolts from the torque converter and slide it back. I believe the noise will be the same unless its the starter. As I posted in another short reply above "Before I put in the bolts into the flex plate for the torque converter I made sure to spin it towards the drivers side of the transmission to make sure that it was seated properly. Then after that I slide it forward maybe 1/8" so it would touch the flex plate to put the bolts in."

[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.

[weim55]

One time a truck that came in the shop with a similar sound. Turned out the owner swapped in a used engine and used the flywheel bolts from a stick flywheel (too long) on his thinner flexplate for the automatic that was in the truck. The too long flywheel bolts were rubbing-hitting the back of oil pan flange on the block. Easy to see with a flashlight from under the truck.....

Steve weim55 Colorado

[DransportGarage]

Originally Posted by weim55

One time a truck that came in the shop with a similar sound. Turned out the owner swapped in a used engine and used the flywheel bolts from a stick flywheel (too long) on his thinner flexplate for the automatic that was in the truck. The too long flywheel bolts were rubbing-hitting the back of oil pan flange on the block. Easy to see with a flashlight from under the truck.....

Steve weim55 Colorado

I wouldn't be surprised that this is it. To me, the noise sounds like it's being generated by something outside the block. After checking this, I'd do the autopsy on the filter as dsraven suggests. Good Luck!