High pitched whine make it stop...

[hillytim69]

I've been working on this truck all spring and summer, 75 Stepside 383, th-350. I think it may have a curse on it though. Some of the work done includes front end, all new control arm bushings and front end parts, sm465 to th350 conversion with B&m floorshifter and new B&M torkmaster 2000 converter. Manual to power steering conversion, all new brake lines from inline tube and new brakes all around etc... I finally got it running, driving, front end aligned, etc. But i have been chasing down a noise all along, i replaced the flexplate which was warped and wobbling which got rid of some noise under acceleration. But i still have high pitched whine kind of like a slightly slipping belt noise. It does not sound like a pump whine. It seems to come fro the torque converter/ tranny area. i removed the acc. belts to rule out the alt/ps/wp and stuff. Funny thing is you don't hear it until every thing is up to operating temp. It seems constant with rpm and occurs at all times in gear or in park. Trans is a fresh rebuild from a local rebuilder and seems to work fine. The 383 runs strong, trans shifts nice, all would be great if not for this squealing whine! I think it may be the converter, has anyone ever heard of a new converter causing symptoms like this? Doesn't happen until it gets hot so I'm thinking something inside is too tight. This is a bummer but I just have to keep at it till its right. Just wish there was a way to tell if its the converter or trans. I've had lots of projects, old trucks, 3 Chevelles, etc. Havent had my arse kicked this bad since my first 350 rebuild when I was 19. I used .010/.010 bearings not realizing the crank was ground .010/.020! Lots of learning "opportunities" to be had.

[Driveway Dreams]

Have you asked your tranny guy about the converter? That seems to be were you have narrowed it down to and it could be the issue from what I have seen before.

[hillytim69]

No, haven't gotten through yet but will call him later. What kind of issues have you seen similar to this? I really think I'm on the right track here though. If it turns out to be the converter I think I'm screwed because I bought it over a year ago but just installed this spring. Still have the receipt from Summit but doubt they would warranty it now.

[old Rusty C10]

perhaps the pump in the trans is bad? i had a 74 impala do that

[East End K5]

Any chance it could be vacuum? I say this because I had a high pitched whine as well, thought it was a pump, pulley or some type of vacuum leak, then I realized one of the nuts were stripped on top of the carb mounted to the manifold causing a high pitch vacuum leak, i tightened them up because the whole thing was pretty loose, quiet and purring like a kitten now, don't get frustrated you'll get it.........my .02 cents

[hillytim69]

Well I've been thinking its the converter or possibly the trans front pump. Tranny is "rebuilt" but its a small timer in his garage so I know the pump is re-used if it looks ok. Guess I can unbolt the flexplate and see what happens. Thanks for the ideas. I don't think its a vacuum leak but will look into that. Stranger things have happened. I think I'm gonna take a break from any major wrenching (pulling trans again) for a couple weeks and spend some time with the family maybe take the kids camping. Then maybe I'll be ready and motivated to work on this truck again...

[hillytim69]

My tranny builder said to try some washers between the flexplate and converter to push the converter a little more into the pump. Otherwise he thinks it may be the pump bushing or pump. My question here is how hard is it to R&R the pump in a th350? I see TCI has a reman unit for about $85. I was thinking of replacing the pump AND converter so I don't have to keep taking the trans on and off over and over. I know you need a couple slide hammers to get the pump off but is replacing it pretty much a nuts/bolts job? I just want to get it on the road before summer is over

[truckincurt]

u dont need the spical slide hammer to take it off just a bolt that fits the thred and somthing to yank on the bolts iv used pilers before witha buddys help on person on each side but th350 very simple trans.... and iv never heard anything good from b&m torque converters stick with good ol tci

[dammitmitchell]

is the starter new?
it could be a stuck wormgear.. starter electrically disengaged but stays stuck.......

maby...

[f.monroe]

I would deefinitely unbolt the torque converter from the flexplate , slide the converter back , and start the engine . See if the whine is gone or not . That will tell you whether it is the engine or trans. I would also recheck all of the bellhousing bolts . I have seen them back out causing engine/trans misalignment issues .
Frank

[hillytim69]

I'll do that first before I try the washer trick. Will post what I find later.

[hillytim69]

Undid the converter bolts and noise still there, not the trans. Sounds like some crickets in my engine or a teapot whistling. I've got a bunch of crazy ideas, like its a 383 with a regular base circle cam but if something was hitting i think it would be a more catastrophic sound. Also thought about the crank shaft thrust bearing. Also thought about my oil pump a high pressure std volume from jegs, it was all my 1/2" Milwaukee electric drill could do to prime the system does that seem normal? I doubt any 3/8 drill could've done the job. But i have great oil pressure. Heres my less extreme idea:maybe the intake isn't sealing up tight on the back by the distributor. I also noticed my distributor didn't just drop in nice the first time, possibly due to the alignment of the intake manifold to the engine. I think I'm going to try removing the intake, install new gaskets and not fully tightening the bolts until I put the dist. in and everything is aligned. I will try a different distubutor this time. the noise seems to be coming from the back of the engine somewhere, what do you guys think of my theory about the distributor making noise or maybe the intake seal? Gotta keep at it...

[f.monroe]

Sounds like a vacuum leak then . Plug all vac sources and fire it . Could be a brake booster leak . You can use a chemical spray to spray around the intake to see if the idle changes or the noise goes away . If you find a vac leak using a aerosol spray , the idle will change . I usualy use carb cleaner but I do not know how detailed your engine is . Use something that wont harm the finishes . I have also seen distributors cause a whine when the cap was misaligned . Starter bendix not retracting maybe . You can check that easy . Look under it and see if the starter is engaged with the flex at all times .
Frank

[jd74c-10]

try putting two gaskets on your dist. to lift it up a few thousands i had one whine like hell before until i lifted it up a bit. just my 2 cents. always look for the easiest answer first.

[hillytim69]

I was thinking about that overnight. The block has been decked I know because the id stamping on the surface on the right front of the block is all gone. It could be possible the dist. is sitting down too far. Thanks and I'll give it a try.

[hillytim69]

Pulled distributor today, it wasn't bottomed in the block but i did find lots of rusty powdery residue under the rotor and noticeable sideways shaft play in the housing. I believe this is the problem. its a stock OE dist from a 79 c20 so guess I should've known better. I have another distributor but it is broken where the springs/weights attach on one side. BUT it does n't have the shaft play like the one i was running. Now I need to know where to get a decent HEI for cheap. What do you guys think of the $42 Skipwhite china made ones? Or the Summit brand for $89? Is there a difference or should I buck up for the low end MSD unit at $143? Looking at Summit catalog right now, Mallory unit looks just like Skipwhite import. hate to pay brandname prices if they are imported crap anyway. iwas disappointed to see my B&M Z-gate was made in China, its buyer beware these days...

[jd74c-10]

before you spend money . clean up you old dist. lube the bushing's ,reinstall and see if it is still whining. if it is quiet, order one from summit,or jegs and don't look at the made in ???? label. you should also go to autozone and buy a automotive sthetoscope so you can find all the little noise's in your truck. go luck, Jim

[1985-GMC]

I had a high pitched whining noise once, i thought it was coming from the throw out or pilot bearing so i pulled the 4 speed, changed them out and clutch while i was at it, put it back in and still had the noise. it turned out that the rubber in the harmonic balancer was bad and the out side was rubbing on the timing chain cover. I would check this next if its not the distributor. Just my 2 cents.

Tony

[hillytim69]

just a true roller chain under a stock steel cover

[jd74c-10]

i had a high pitched whining noise once. so i stopped the truck ,told the girl friend to get out, drove away and haven't heard it since.

[KQQL IT]

Originally Posted by jd74c-10

i had a high pitched whining noise once. so i stopped the truck ,told the girl friend to get out, drove away and haven't heard it since.

Thats good stuff right there

[jd74c-10]

so what did you find wrong?