Truck making weird noise at startup

[Low84]

What's up guys. Let's see if anybody can help me out on this one.

My truck has recently started to make a really, REALLY, harsh sound at startup. I'm talking grinding, clunking, spinning, type of sound and LOUD. People turn around from pretty far away staring with a puzzled expression. It's embarrassing to say the least.

I thought maybe it was the starter that had come loose and was making false contact. I checked it and everything seems alright.

Correct me if I'm wrong as I obviously have no clue what I'm about to say.

Does the starter engage the flywheel and spin it, to start the engine? Could it be a broken flywheel, or teeth on the flywheel that is causing all of this?

I'm pretty sure something is getting damaged real well every time I start it up, because that much noise and that loud can't mean anything good. It's only a matter of time before I get stranded somewhere.


Somebody help, please.

[Srubydo1986]

yes when the starter ingages it slides out and spins the flywheel if its not coming out completely or some teeth are broken it can cause that noise. I say remove inpection plate and inspect flywheels teeth also remove starter and inspect it as well. cause if it continues u may have to rplace flywheel if u dont aready.

Replaceing starter is on thing flywheel is another

[Low84]

Originally Posted by Srubydo1986

yes when the starter ingages it slides out and spins the flywheel if its not coming out completely or some teeth are broken it can cause that noise. I say remove inpection plate and inspect flywheels teeth also remove starter and inspect it as well. cause if it continues u may have to rplace flywheel if u dont aready.

Replaceing starter is on thing flywheel is another

Thanks for the info. The starter is realatively new and ontop of that, I removed it about two months ago and had it inspected. Everything checked out fine.

So, it is more than likely going to be the flywheel. By the way you said it, I take it it's not a cheap thing to get replaced?

[Restrorob]

The transmission must come out or at-least be slid back enough to get to the flywheel mount bolts.

One other thing is when the flywheel is replaced (if needed...cough cough) make sure to check the starter drive tooth Clarence to the flywheel teeth. If the Clarence is too great it could cause pre-mature starter drive and flywheel failures. There are shims available that will increase or decrease the Clarence when installed properly.

Good Luck !

[Srubydo1986]

na is mor eof a pain to replace flywheels arnt to expensive just a pain. never done it with out taking motor out. But been told u can unhook torck converter from flu wheel and slide it and transmission back the unbolt flywheel then remove it. Sounds easy but like i said never done it without removing motor. (also my vehicals were low to gound chevelles and low trucks nissans. and i dont have a lift)

[jpoutlaw]

Mine makes some noise too. I have found if I tighten the second bolt (fatherest back) first, then the closest one, I don't get that noise. Mine periodically needs tightened and so that's what I do. Thought about putting lock nut on there so I don't have to keep tightening it but it's about once a month and too cold to sit underneath for any length of time. Hope this helps. The flywheel would be a pain but I think your problem is with the starter.

[Slonaker]

Is the noise just when the starter is engaged, or does it happen after the engine starts and the key is released? If it is while the key is turned, I agree with the others. If it is after the key is released, I would look for a bent or cracked flexplate.

The flexplate (AKA flywheel) isn't too bad to replace if you unbolt the trans and just slide it back enough to replace it. I have only done 6 or 7 transmissions, and it only takes me an afternoon with my big clumsy hands.

Slonaker

[Low84]

It's while I'm cranking the engine. It sounds like something is grinding and slipping, along with clunking, and a medium pitched but very loud scratching sound.

I would take a vid tomorrow, but my camera gave out on me.

[PhilaTruck]

SRUBYDO had it. If it's making that much noise and it's the flywheel, it'll show on the teeth. Good luck!

[Malo83]

My 83 did the same thing, it was the flywheel

[Low84]

Alright, I'm heading back home today. I'm going to see if I can get the truck fixed.

The flywheel for our trucks th-350 use the 168 tooth flywheel correct?

[jberkeley]

had same problem on mine, turned out to be the timing, check that first. good luck

[Low84]

Originally Posted by jberkeley

had same problem on mine, turned out to be the timing, check that first. good luck

Really! That hadn't crossed my mind. I know the timing is not right because when I took the carb to get adjusted before I had it rebuilt, the guy messed around with the timing and followed the recommended timing on the sticker. Problem was the sticker is for a 305 and I have a 350. Then he just adjusted it to where it sounded better. I'll take a look into that.

Thanks.

[Srubydo1986]

i do timing by book then by hearing it.

[mrjs80]

My 80 did that. Took the inspection cover off and two bolts fell out with it. They were for the torque convertor. It was about to fall off! Put some lock washers and thread lock and havn't had a problem since.

[Low84]

Thanks for the help guys. It WAS indeed the starter. Very weird, all the previous starters had just gone out on me from one day to the other. Got the new starter in there, and I swear the truck almost feels faster. I don't know what happened but it really woke up! I'm not playing, I'm going to take it to the track one of these days to confirm this.

[PhilaTruck]

What kind of starter is that? Must be helping the flywheel spin!

I could use a couple of 'em!

[Slonaker]

Mine feels faster after I wash it.

Glad you got it fixed.

Slonaker

[84slopwaggin]

Good fix Man. I got 3.42's and my truck feels faster. Now I got to get this mini starter installed.

[Low84]

Originally Posted by PhilaTruck

What kind of starter is that? Must be helping the flywheel spin!

I could use a couple of 'em!

I know, I sound like a ricer with a brand new sticker. LMAO!

Originally Posted by Slonaker

Mine feels faster after I wash it.

Glad you got it fixed.

Slonaker

What soap do you use? LOL


Its probably a combination of all the thing I've been doing to the truck that finally had an effect.

I've been dumping money into it like crazy, and I'm finally getting results.

I replaced all 4 tires.
Replaced fuel lines and filter.
New battery and terminals
Oil change.
Fixed the exhaust leak.
Rebuilt Carb
had the timing semi-adjusted
and now the new starter.


To do:
I have some Hedman Headers that I plan on installing in the near future.


I feel at the very least a half second faster. But then again I don't think I can go any slower than 19.00

[Zilverado]

Originally Posted by Low84

...Got the new starter in there, and I swear the truck almost feels faster. I don't know what happened but it really woke up! I'm not playing, I'm going to take it to the track one of these days to confirm this.

I'm guessing that this is a psychological result of fixing the problem. I know that's how it works with me. I tend to "baby" the truck a bit when strange things are happening. Once all is well again, the skinny pedal always feels a little looser.

Seriously though, I'm glad it worked out so well for you. A starter replacement is sure a whole lot easier (and likely cheaper) than the flexplate - especially if you do not do the work yourself.

Have fun with SPEEDY - just watch out for the bears.

[84slopwaggin]

Another way to syke out your mind is to add return springs to your throttle linkage adding resistance to your throttle travel. It will seem like you've gained some added torque .

[PhilaTruck]

The carb rebuild alone would be enough to feel a boost in power or more like getting it where it's supposed to be. You'll like the headers. Have fun!

-Todd