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Old 01-01-2019, 09:06 PM   #1
NeoJuice
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What's going wrong inside my 350?

Purchased the truck back in Nov of 2016 as a partial finished build. Link to unfinised build thread below. I stopped updating the thread because of photobucket.

http://67-72chevytrucks.com/vboard/s...d.php?t=723325

Engine is a 1978 Fresh rebuilt chevrolet 350 with .030" bore over and mild cam. Has a 700r4 corvette servo, Stage 2 shift kit, Beast sun shell 3000 Stall converter &
B&M Unimatic Shifter as I was told.

I've started the truck maybe half a dozen times since about september and there were no issues except for the timing and carb calibration needing done and it being loud as HELL. On December 19 I trailered it to the exchaust shop to have the exhaust installed because of good weather. I didnt think I was going to be able to get it done until spring so it put me one step closer to get it on the road come spring.

Since the truck is in pretty poor timing and the carb needing tuned the truck was winched up onto the trailer. Unloaded using the winch at the exchaust shop, pushed into the shop, pushed out of the shop and winched back up onto the trailer and towed home.

When I got the truck home we decided to try and start the truck to hear how the new exhaust sounded. Well that opened another can of worms b/c I was pissing transmission fluid out one of the hoses on the passenger side of the transmission. After some further investigation that just turned out to be a loose hose connection. After a couple more starts the truck starts to make this hell of a screaming noise coming from the bottom end of the engine. I pulled the alternator and belt off and tried it again. Same noise so it's not coming from the water pump or alternator.

After investigating around underneith the truck to try figure out what the noise was, I found the torque converter wasnt even bolted to the flex plate. WTF? I could spin it freely with my hand. I figured this had to be the problem maybe the snout of the torque converter was rubbing up against the flex plate making the noise. So I went to my local transmission shop which happens to be located next to the exhaust shop and got the three missing bolts at $5each.

I installed the bolts into the torque converter and got the bolts torqued to spec. I figured this would now fix the squeeling noise & vibration and it didnt. So I re-installed the alternator and belt because I know they were good. I started to do some googling and youtubeing and found that 'maybe' it might be due to vacuum inside the block. So I pulled the PVC valve out of the valve cover and the breather on the passenger side and proceeded to try and start the truck again. Same noise. Either then the timing being off and carb needing tuned I'm not sure what is going on inside the block. Here is an example why I gave this a try.

https://www.youtube.com/watch?v=M5eEitHdsXc

I did tons of searching from flex plate failure, engine knock, bottom end failure, rear seal replacement, harmonic balancer replacement and cant find anything simular to what I'm experiencing. So here I am posting to find out if anyone might know possibly what might be going on. It doesnt make sense since each time I've started the truck before it just ran rough because of timing/carb calibration.

Since this was a partial finished build I'm thinking the guy B.S'd me into thinking this was a rebuilt engine and tranny. I'm not saying it's not, but now this happens. It's weird because I'm getting real good oil pressure on my gauge. I've yet to pull out my compression tester to check the cynlinders. Any insite on what might be going on would be much appriciated. I'm hoping that I dont have to pull the motor & tranny. I paid top dollar for the truck because of the work completed and was told it was a frech rebuild.

I took two videos today and posted them to the link below. I also included the first startup video that I took back in September. Hopefully the shared links work. Thank you everyone for your time.

September first start & Top Engine noise from the top
https://photos.app.goo.gl/EAqnZqKHPN5WNPZW6

Under Truck Torque Converter flex plate.
https://photos.app.goo.gl/qUP6BQRNsuhLtN427
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Old 01-01-2019, 09:43 PM   #2
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Re: What's going wrong inside my 350?

Since I can't get videos to play I'll take a stab at it...is the bendix releasing?

Ok I got last video to play...sounds like the bedix... starter may need shimming...(my guess)
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Old 01-01-2019, 10:04 PM   #3
NeoJuice
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Re: What's going wrong inside my 350?

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Originally Posted by mongocanfly View Post
Since I can't get videos to play I'll take a stab at it...is the bendix releasing?

Ok I got last video to play...sounds like the bedix... starter may need shimming...(my guess)
Yes I believe it's disengaging properly. When I was under the truck I didn't see it engaged against the fly wheel when the truck wasn't running. I was a little hesitant climbing all the way under there when the truck was running. This noise is coming from the block/crank area but you might be on to something. I will need to check it out further to see if that is the case. If that is the case why would this just start to happen? Wouldn't it pretty much burn out the starter right away? The noise does not appear to be coming from the starter side of the motor as far as I can remember. Possible bad flex plate?

Last edited by NeoJuice; 01-01-2019 at 10:26 PM.
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Old 01-01-2019, 10:41 PM   #4
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Re: What's going wrong inside my 350?

Dose sound like starter drive hanging up. Did you check trans oil if ok. If you take a heater hose or any small hose and put it at diffrent spots on the area with the other end to your ear you should be able to tell where the noise is coming from. Acts like a stetascope.
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Old 01-01-2019, 10:42 PM   #5
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Re: What's going wrong inside my 350?

Buy a cheap stethoscope from Harbor Freight, or simply put a piece of rubber fuel line up to your ear and you will easily be able to isolate the offending noise.
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Old 01-01-2019, 11:14 PM   #6
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Re: What's going wrong inside my 350?

That's an interesting sound. Does it do it as soon as the engine is started? Is it louder toward the front or rear of the engine? Can you hear it during cranking if the coil is disabled? Is cranking speed normal?

It sounds like a bearing and it could be on the crank. If a rod bearing has spun slightly and is wedged against the crank the oil hole from crank to bearing can become restricted which keeps the oil pressure from dropping.

It's also possible a timing cover is touching the balancer or that there's something wedged against the oil pump drive but those sounds are usually different. The balancer noise is a bit tinnier and the oil pump drive isn't as loud. But the problem with a video is it's hard to get relative sound levels.

But I have heard a strange squealing before that can sound very bad but is actually easy to cure. If the PCV valve is doing its job and drawing air out of the crankcase but there is no way for air to enter the crankcase, air will begin to flow past the main seals. It is very loud. This happened in one case because a set of cheap chrome valve covers came with grommets that weren't actually opened so the breather could not pass air into the engine. In another case an individual installed a PCV vavle in each valve cover not knowing one needed to be vented. In both cases the noise started several seconds after engine start. If you suspect this may be a problem, the easiest check is to ensure the crankcase is vented, possibly by pulling the PCV valve while the engine is running.

Also, mild cam plus 3000 stall converter??? That may not give you the performance you want. But it may not be an issue...
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Old 01-01-2019, 11:16 PM   #7
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Re: What's going wrong inside my 350?

I've become a bit of a skeptic over the years as I have come to believe that you can't call an engine "rebuilt" unless you see the receipt from the machine shop for the engine work and the receipts for the parts that are supposed to be inside of it.

I've seen too many guys selling "rebuilt" engines around here that had a quickie valve job, a ball hone job and a trip to the car wash to wash them up before being reassembled with a low buck ring and bearing kit. Nothing wrong with that if you are putting a driver motor together for yourself but it is false advertising if you are selling the engine as rebuilt.

Right now it boils down to check everything just as if you had pulled the engine off a stand and installed it yourself. Check for what else they didn't do right or didn't finish. Don't assume anything except that you need to check everything.
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Old 01-01-2019, 11:37 PM   #8
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Re: What's going wrong inside my 350?

I would drain the oil to see if it's clean
also what type of filter is on this Engine if it is orange (fram) I would have conerns
Because No rebuilder would use a fram unless they were on a low buget
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Old 01-02-2019, 12:32 AM   #9
NeoJuice
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Re: What's going wrong inside my 350?

Quote:
Originally Posted by duramax55 View Post
Dose sound like starter drive hanging up. Did you check trans oil if ok. If you take a heater hose or any small hose and put it at different spots on the area with the other end to your ear you should be able to tell where the noise is coming from. Acts like a stethoscope.
I will have to check the starter and see if its hanging up but unfortunately keeping the truck running and filming video is a two person job until i can get some help.

Its a god awful noise that seems to be resonating right through the crank out the front of the motor. I looked at the teeth on the flex plate and there is no wear or worn teeth.

Thank you for the suggestion.
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Old 01-02-2019, 12:32 AM   #10
NeoJuice
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Re: What's going wrong inside my 350?

Quote:
Originally Posted by MiraclePieCo View Post
Buy a cheap stethoscope from Harbor Freight, or simply put a piece of rubber fuel line up to your ear and you will easily be able to isolate the offending noise.
Will do. I have some spare hose.
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Old 01-02-2019, 12:49 AM   #11
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Re: What's going wrong inside my 350?

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Originally Posted by 1project2many View Post
That's an interesting sound. Does it do it as soon as the engine is started? Is it louder toward the front or rear of the engine? Can you hear it during cranking if the coil is disabled? Is cranking speed normal?

It sounds like a bearing and it could be on the crank. If a rod bearing has spun slightly and is wedged against the crank the oil hole from crank to bearing can become restricted which keeps the oil pressure from dropping.

It's also possible a timing cover is touching the balancer or that there's something wedged against the oil pump drive but those sounds are usually different. The balancer noise is a bit tinnier and the oil pump drive isn't as loud. But the problem with a video is it's hard to get relative sound levels.

But I have heard a strange squealing before that can sound very bad but is actually easy to cure. If the PCV valve is doing its job and drawing air out of the crankcase but there is no way for air to enter the crankcase, air will begin to flow past the main seals. It is very loud. This happened in one case because a set of cheap chrome valve covers came with grommets that weren't actually opened so the breather could not pass air into the engine. In another case an individual installed a PCV vavle in each valve cover not knowing one needed to be vented. In both cases the noise started several seconds after engine start. If you suspect this may be a problem, the easiest check is to ensure the crankcase is vented, possibly by pulling the PCV valve while the engine is running.

Also, mild cam plus 3000 stall converter??? That may not give you the performance you want. But it may not be an issue...
-Yes it does it as soon as the engine is started.
-its hard to tell if its louder towards the front or rear of the engine but i would suspect the rear of the engine as in the video.
-engine cranking appears to be normal.
- I pulled the pcv valve on the drivers side and the vent on the passenger side to open things up just in case there was a venting issue. Same results.
-ill investigate the spun rod bearing and see if i can figure out what is happening. i hope to god its not a spun rod bearing. There doesn't appear to be any banging/tapping during idle just the squealing heard in the videos.


Thank you for your input.
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Old 01-02-2019, 12:52 AM   #12
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Re: What's going wrong inside my 350?

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Originally Posted by mr48chev View Post
I've become a bit of a skeptic over the years as I have come to believe that you can't call an engine "rebuilt" unless you see the receipt from the machine shop for the engine work and the receipts for the parts that are supposed to be inside of it.

I've seen too many guys selling "rebuilt" engines around here that had a quickie valve job, a ball hone job and a trip to the car wash to wash them up before being reassembled with a low buck ring and bearing kit. Nothing wrong with that if you are putting a driver motor together for yourself but it is false advertising if you are selling the engine as rebuilt.

Right now it boils down to check everything just as if you had pulled the engine off a stand and installed it yourself. Check for what else they didn't do right or didn't finish. Don't assume anything except that you need to check everything.
mr48chev,

I've taken your advise on this before and if you dont check every nut and bolt yourself then you don't know its right. As I mentioned in my post above there was no bolts in the torque convert to the flex plate. I've come across many WTF moments in this build. You can only count on yourself to make sure its done right the first time.
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Old 01-02-2019, 12:53 AM   #13
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Re: What's going wrong inside my 350?

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Originally Posted by Softpatch View Post
I would drain the oil to see if it's clean
also what type of filter is on this Engine if it is orange (fram) I would have conerns
Because No rebuilder would use a fram unless they were on a low buget
I did check the oil today and its clean as day. Yes I put a frame filter on it when I changed the oil.
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Old 01-02-2019, 01:03 AM   #14
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Re: What's going wrong inside my 350?

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.
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Old 01-02-2019, 01:41 AM   #15
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Re: What's going wrong inside my 350?

You might check out the flex plate for a crack, and make sure it's bolts are tight.
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Old 01-02-2019, 07:36 AM   #16
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Re: What's going wrong inside my 350?

Quote:
Originally Posted by mr48chev View Post
I've become a bit of a skeptic over the years as I have come to believe that you can't call an engine "rebuilt" unless you see the receipt from the machine shop for the engine work and the receipts for the parts that are supposed to be inside of it.

I've seen too many guys selling "rebuilt" engines around here that had a quickie valve job, a ball hone job and a trip to the car wash to wash them up before being reassembled with a low buck ring and bearing kit. Nothing wrong with that if you are putting a driver motor together for yourself but it is false advertising if you are selling the engine as rebuilt.

Right now it boils down to check everything just as if you had pulled the engine off a stand and installed it yourself. Check for what else they didn't do right or didn't finish. Don't assume anything except that you need to check everything.
I'm with Mr 48chevy pull the motor and start over
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Old 01-02-2019, 09:44 AM   #17
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Re: What's going wrong inside my 350?

What's the oil pressure? Since someone was into the transmission as well - installing significant mods - I would do a pressure test, then pull the pan and look for shavings at the trans filter. An easier test might be to send a sample of trans fluid and engine oil to somebody like Amsoil:


https://www.amsoil.com/shop/by-produ...ysis-services/

Whatever you do, isolate the problem to either the engine or the transmission before you start pulling the truck apart. Just sayin'...
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Old 01-02-2019, 01:24 PM   #18
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Re: What's going wrong inside my 350?

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Originally Posted by whitedog76 View Post
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.
When I get a chance I will check to see if the starter is getting hung up. I'm hoping that is the problem.

What are the symptoms of a spun bearing either then grinding/squealing?

I havent checked the flex plate yet. that would require removing the transmission.

When you say front pump? Do you mean the water pump? I disconnected the belt from the motor and turned it over to the same sounds.
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Old 01-02-2019, 01:25 PM   #19
NeoJuice
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Re: What's going wrong inside my 350?

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Originally Posted by PDW HOTRODS View Post
You might check out the flex plate for a crack, and make sure it's bolts are tight.
After I check to see if the starter is hanging up I'll probably go this route to check the flex plate. If the starter is hanging up would it still be engaged to the flex plate when the ignition is not on? When i looked at it with the truck turned off I couldnt see the bendix engaged to the flex plate. So I'm assuming its functioning correctly. Unless once the ignition is turned it keeps on engaging against the flex plate until the motor shuts down.

I'm not sure.

Last edited by NeoJuice; 01-02-2019 at 01:45 PM.
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Old 01-02-2019, 01:36 PM   #20
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Re: What's going wrong inside my 350?

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Originally Posted by DransportGarage View Post
What's the oil pressure? Since someone was into the transmission as well - installing significant mods - I would do a pressure test, then pull the pan and look for shavings at the trans filter. An easier test might be to send a sample of trans fluid and engine oil to somebody like Amsoil:


https://www.amsoil.com/shop/by-produ...ysis-services/

Whatever you do, isolate the problem to either the engine or the transmission before you start pulling the truck apart. Just sayin'...
The oil pressure on my gauge is reading about 55-60 PSI on idle. it's hard to get an accurate reading because the timing/carb tuning is all off and trying to get it to run smoothly is a challenge to get an accurate reading.

I will be checking out the starter just in case it's hanging up then probably look at the flex plate. Then if anything else then compression test and hopefully it's not something in the motor. Last thing I need right now is to replace the engine.
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Old 01-02-2019, 01:39 PM   #21
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Re: What's going wrong inside my 350?

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I'm with Mr 48chevy pull the motor and start over
I'm hoping that I don't have to do that. And of course I have no recourse because the truck was sold as is/where is. I paid more then I would have if it didn't have all the 'work' done to it, which was probably under false pretense. It makes me so upset I have a pain in my gut. Could I go after him? it's been like 2 years now.
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Old 01-02-2019, 02:10 PM   #22
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Re: What's going wrong inside my 350?

-remove the engine oil filter and cut it apart with a good utility knife (or filter cutter) to check for anything metallic in the filter medium. while it is off check the filter adapter and bypass valve to ensure it is all bolted up correctly and the bypass is operational and not causing a squeal. if in doubt simply replace the adapter since they are fairly cheap anyway. like mentioned in an earlier post you could send out an oil sample but that is a bit spendy and takes time. anything major will have caused something to show up in the filter so this would be considered a preliminary check before doing that. if metallics are found then pulling the engine apart would be the next step. also, like said, use a good quality filter, especially on a new engine, to trap as much debris and new engine break in metalics as possible. personally I would not use a Fram filter on my lawnmower but that is just me. some will use a cheap filter on new engines because they feel it is expensive to put a good filter on and then simply swap it out right away after a few runs or hours on the engine. to me that is reverse thinking and I would use the best filter I could on a new engine because that is when you know there will be fluff from shop rags, dust and dirt from the rebuild process etc. and that is when you need the best filter you can get. just me being me though
-ensure you have end play in the crankshaft since no end play could also make the thrust bearing work overtime and possibly make noise
-check for any vac leaks that may cause a whistle. look around the base of the carb to ensure any and all vac ports are used or capped and there are no cracked hoses or leaking vacuum actuators like a trans modulator hose/tube/valve. check the brake booster manifold fitting, hose, check valve. carb base gasket etc. pinched modulator hose or tube at the bell housing to engine flange (hey, it happens).
-check to ensure there isn't a timing tab rubbing on a pulley, check the pulleys to ensure any bolt on pulleys or accy are tight and fitting correctly. look for any odd rub marks on anything up front. look at the vibration damper and check for movement of the outer ring. a quick marker line across the two parts will show any movement after the engine has run and been shut down. squished out or deformed rubber in the damper joint of the 2 parts is usually an indicator of a possible problem or future problem. I have seen some of these parts "cleaned" improperly using solvents that attack the rubber ans cause the 2 parts to move/separate
-check for any odd heat marks or paint discoloration on the timing cover that may indicate an issue with a loose timing component or wrong fastener used inside there
-check the valve covers to ensure they are installed correctly. if installed incorrectly the rockers can rub on the covers. if not too inconvenient you could also remove a cover and check to ensure the top end is getting oiled properly and everything looks like it should
-check mechanical fuel pump and/or pushrod for issues. the pushrod could be "held' with a bolt in the front area of the engine if there is a bolt used there that is slightly too long. this would likely cause the pump not to operate but it only takes a sec to check anyway
-run the engine and use a stethoscope with an open hose around the base of the carb and top/front engine area to eliminate this area. check the distributor as well because a bad distributor shaft bushing could make a similar noise or a ruptured vac advance diaphragm may whistle. the same goes for a trans shift modulator valve
-jack the truck up high enough and block it to safely work under the truck if the engine were running. try to keep the angle of the truck the same as when it sits on the ground so you have the best chance of reproducing the noise
-remove the torque converter cover and look inside it for any metallic dust or other tell tale signs.
-remove the vac line at the shift modulator and look for fluid inside the hose that may indicate a ruptured diaphragm. ensure the metal vac tube (if equipped) is in good condition and doesn't have a torn off mounting bracket that could cause a whistle through the spot weld holes on the tube
-look up inside the bell housing at the starter drive and flywheel tooth contact area. check deep into the teeth to see if these parts have been bottoming out during contact. a quick spray with some paint in the tooth area would show the contact pattern after the starter was used. small block chevies usually need a few shims and some trial and error to get the starter drive to contact the flywheel correctly. they may just not sound right or they may engage and stay engaged if not shimmed properly. a starter that stays engaged will make noise and may fly apart when the engine is revved. this is due to the rpm the starter is forced to work at when the engine revvs up plus the crude drive tooth engagement would make noise at rpm. you could also remove the starter and physically check it out. if you disconnect power to the distributor you could use a remote starter switch or some other method (like a buddy in the cab) to crank the engine while you watch how the starter is working to ensure there is no problem there.
-check to ensure the torque converter is slid all the way into the crankshaft. since the engine was ran without the torque bolted in the snout of the torque or the end of the crankshaft may have been slightly damaged so they may not have been able to slide fully into the together. this would mean the flex plate would be required to take up the slack by flexxing or becoming slightly bell shaped. this may cause a harmonic when running. when unbolting the torque the 2 parts should be able to be slid together without having to be pulled in with the bolts. the torque should also be easily slid into and out of the crankshaft. when pushed back into the trans there is also a dimension as to how far the torque is allowed to be pulled out of the trans to bolt up to the flex plate. too much dimension here would mean the torque is not fully engaged in the trans pump correctly. not enough dimension could also be a problem. since the trans and engine were apart and you didn't do the work you are coming into it with no history as far as what was done or if the torque is the correct one etc
-check the front of the torque to ensure there was no damage that may cause interference of the internal converter moving parts with the "dent" in the converter shell or a distorted fastener mounting flange, if any dents or distortion are present.
-check to ensure a torque drain plug (if equipped) was/is positioned so it lines up with a hole in the flex plate. if not the flex pate could be distorted causing the harmonic.
-check to ensure all the flex plate to crankshaft bolts tightened down correctly and fully. we assume the correct length bolts were used. cracks in the flex plate are common around the mounting flange to the crankshaft
-check the flex plate for cracks all the way around the crank flange and also around the torque mounting areas. turn the engine by hand and check the whole way around. look for metal powder anywhere and also flex the flexplate as you go and listen for the sound of metal moving on metal as would be heard if there were a crack. check to ensure the flex plate was installed the correct way around and not backwards. these checks in this area can be hard to do but could be made easier if you placed some long bolts in the trans bell housing to engine mounts and use them as line up pins to slide the trans back enough to see into the area. that way ir could be easily slid back together after and wouldn't require support (that would be in your way) while slid back
-check to ensure the flex plate to torque mounting bolts are the correct length and did not cause a dent or distortion of the torque shell that, again, may cause interference with the internal converter moving parts
-check to ensure you have the correct converter for your trans (hey, it happens)
-if these things all look good then bolt everything back up carefully except leave the converter cover off. install a new oil filter and top up the fluid
-start the engine and slide under (carefully, ensuring no loose clothing etc) and use your stethoscope to try to pinpoint the area where the noise is coming from. use the open hose at first and then the probe rod to be more specific. I highly recommend a stethoscope because it deadens ambient noise so you can zero in on a particular area. be aware that the hose can also get snagged on moving parts. what I have done is grab a scope that has the ability to replace the hose with a longer hose so I can be physically further away from moving parts.
-check for exhaust system whistles which can be caused by welds that have slag inside the pipe unseen from the outside or poor pipe connections with flanges or bits inside the pipe that can whistle when the exhaust passes them. I have also see partially plugged mufflers cause whistles that would seem like an engine issue. a couple of weeks ago I was brought a truck that needed an engine, as diagnosed by a dealership, and found the only issue was a plugged catalytic converter and some tune up issues. not saying that could be your problem, just saying eliminate what you can (good job on removing the belts to eliminate the accy's by the way. good thinking there)
-if you still have a noise you will need to pinpoint if it is engine or trans. you may need to unbolt the torque and slide it back then start the engine and do the stethoscope thing again. if you don't have room between the torque and flex plate you may need to space the engine away from the trans enough to get the job done. if you think it is trans then start by pulling the trans pan off and looking inside. I recommend to drain the pan into a clean container so you can look for metallics in the oil and know that whatever found can only be from the trans (or engine if dumping that oil as well). if you do this and your pan does not have a drain plug then now would be the perfect time to remedy that to make things easier in the future.

keep us posted, post pics and video as you see fit. the one link to a video did not have sound (for me anyway)
what is that behind your trans, overdrive unit? possibly an issue there could make the sound you hear?
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Old 01-02-2019, 02:11 PM   #23
dsraven
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Re: What's going wrong inside my 350?

sorry for the long boring write up. i's just stuff I thought about that could maybe help you or somebody else reading.
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Old 01-02-2019, 02:14 PM   #24
whitedog76
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Re: What's going wrong inside my 350?

Quote:
Originally Posted by NeoJuice View Post
When I get a chance I will check to see if the starter is getting hung up. I'm hoping that is the problem.

What are the symptoms of a spun bearing either then grinding/squealing?

I havent checked the flex plate yet. that would require removing the transmission.

When you say front pump? Do you mean the water pump? I disconnected the belt from the motor and turned it over to the same sounds.

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
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Old 01-02-2019, 02:27 PM   #25
Henry50
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Re: What's going wrong inside my 350?

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

I bet the converter wasn't seated properly.
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