Broke another flexplate, what am I missing?

[Rusty Nail]

That sounds like a good tree to bark up to me../shrug


Thanks @paul Harvey

 

[82sbshortbed]

That sounds like a good tree to bark up to me../shrug


Thanks @paul Harvey

Love Paul Harvey!

 

[Cuba]

Alright friends... I may have a WHACKED bell housing. I will share ALL of what I found, but I am specifically concerned about my bell housing... check this out fellas... Considering my alignment pin is in the realm of this shotty work, I really hope someone didn’t break the whole corner off and then try to weld it up by eye.. kind of a precise piece there...

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Trans pump seal leak (if you look close it features my seeping trans pan gasket too )

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Not sure why the starter is chewed up... but there’s that.

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Here is a video demo of the torque converter. At the end, I wiggle the converter and it makes noise. Let me know what y’all think....

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Fitment of converter to flexplate look fine. Typical gap from my opinion & experience... but geeee wizzzz that weld job! That.... that has me concerned although by eye looks decent. Just catching up now, still have a bit more comments to go through.

The wiggle at the video's end looks like pump play? To ME but - I don't know what that is OR looks like even.

You are right about the side to side wiggle. I didnt watch it all the way through. I don't like that either. For sure. I bet you will find worn bushing at the minimum.

 

[79dentside]

Fitment of converter to flexplate look fine. Typical gap from my opinion & experience... but geeee wizzzz that weld job! That.... that has me concerned although by eye looks decent. Just catching up now, still have a bit more comments to go through.





You are right about the side to side wiggle. I didnt watch it all the way through. I don't like that either. For sure. I bet you will find worn bushing at the minimum.

Are you talking about the bushing or the bearing in the front pump?

 

[Cuba]

I'm talking about the bushing. There's a seal. Then bushing. Then pump gears. No bearing... That's not what the converter rides on or touches. Only seal, bushing, & gears.... or input shafts. Strain on those pump gears due to worn bushing is 1 cause of the whining...and will also affect flexplate. Too much vibration & stress.

 

[79dentside]

I'm talking about the bushing. There's a seal. Then bushing. Then pump gears. No bearing... That's not what the converter rides on or touches. Only seal, bushing, & gears.... or input shafts. Strain on those pump gears due to worn bushing is 1 cause of the whining...and will also affect flexplate. Too much vibration & stress.

Ohhhh my bad. Totally figured there was a bearing in there hahahah. Well considering melt seal is bad, I need to tear into it anyways.

Now this ugly repair... do we see any concern with this? If this is problematic, I will need a new transmission.... not liking that...

 

[Cuba]

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[79dentside]

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Perfect, thank you!!!!

 

[Cuba]

Ohhhh my bad. Totally figured there was a bearing in there hahahah. Well considering melt seal is bad, I need to tear into it anyways.

Now this ugly repair... do we see any concern with this? If this is problematic, I will need a new transmission.... not liking that...

I agree. I don't like the look of the housing. Im quite sure the bell housing is part of the case, unlike many modern trans which sucks butt. Then you'd have to find another case. No way to really be sure until it's in front of you. Better yet, your trans guy friend. If he's trust worthy, I'd go with what he suggests. The case makes a huge difference in how a trans operates. Same with line up holes, and why we use dowels. It's so important to be spot on.

 

[79dentside]

I agree. I don't like the look of the housing. Im quite sure the bell housing is part of the case, unlike many modern trans which sucks butt. Then you'd have to find another case. No way to really be sure until it's in front of you. Better yet, your trans guy friend. If he's trust worthy, I'd go with what he suggests. The case makes a huge difference in how a trans operates. Same with line up holes, and why we use dowels. It's so important to be spot on.

Exactly. I will reach out to him and see what he thinks. I agree with you, I feel like this definitely is not helping matters.

 

[BigDaddy72]

I’ll be honest with what I could hear and see it looks fairly normal to me I didn’t really see any side to side movement. Wobbling I mean.

That case is a botched repair job. It looks like it was broken during removal or installing it at one time in its life.

The picture of the starter looks like something has been grinding against the nose cone.

If that case has been repaired in a way that miss aligned it to the block that is going to put it all in a bind.

I think if there is excessive play in the main shaft that it is a result of a mis alignment issue.

Meaning it caused the excessive wear and damage to the internal hard parts of the trans.

As I said before keep checking and eliminating the causes as you go.

I would think your next step would be to remove the trans and get a birds eye view of the back of the engine and the front of the trans. More than likely that botched repair spot and your symptoms are related.

Last question does it have a vibration at idle, under a load, letting off the accelerator while at hwy speeds.

Another words if you play with engine rpm or vehicle speed can you feel a vibration?

Before you pull the trans, fire up the truck with the converter unbolted (just at an idle) and see if your whine disappears and or is different.

Good input and you are making good progress keep checking I’m confident you are gonna get it figured out your on the right track.

 

[BigDaddy72]

@Cuba good input.

I like your approach to the problem. Your honesty and knowledge is a key aspect to being a great tech.

When people are more concerned with a solution than being right thats a sign of person you should listen to and trust. I admire that very much.

 

[bucket]

I do not know if you are working on a C or a K. This only applies to a C . You can change the flex plate without pulling the transmission. Buy some bolts the same length as the starter bolts, pull your bottom 2 bell housing bolts replace them with the long bolts. Unbolt the transmiision and torque converter and slide them back, you will have just enough R&R the flex plate. Again make sure your transmission locating dowels are in place.

This nifty method works with a K truck too. Well, maybe not with the big honkin' 203, but it works with the 205 and 208.

Everything is internal balance except 400 and 454. (Stock stroke Chevy sb and bbc.)

If you had a 350 fp on a 400 or vice versa you would know real quick.

If your crank pilot and the nose of your converter is not correct that will put your entire trans in a bind.

I’ll say it again first thing to check are those to measurements and verify that the converter turns freely in the back of the pilot.

You say the engine has been rebuilt? Does it have an aftermarket Chinese crankshaft in it? Was the converter made in China?

They are not famous for precision tolerance and machining.

Does your starter grind? Is the starter gear stuck against the flexplate?

This will cause a horrible whine.


Is the engine block cracked where the starter bolts up? Causing the starter to shift and bind.

You should do some more diagnostic checks and inspection before throwing parts a a problem that your not 100% sure of.

Triple check all the small stuff before replacing or buying anything else. You will be glad you did and upset if you don’t.

All good input from everyone just back up take it slow and try to figure out how all these symptoms are related.

Does your fluid color look good? Does the trans slip? Is the flexplate rubbing or grinding against anything? Keep checking until the problem reveals itself then repair that.

The '86-up small blocks (1-piece seal) have a flexplate with a balance weight. I don't think that applies here though.


That whacked case looks suspicious...

 

[BigDaddy72]

This nifty method works with a K truck too. Well, maybe not with the big honkin' 203, but it works with the 205 and 208.



The '86-up small blocks (1-piece seal) have a flexplate with a balance weight. I don't think that applies here though.


That whacked case looks suspicious...

You are correct the 1pc rms and 2pc rms are different crank bolt patterns too.

 

[Blue Ox]

Exactly. I will reach out to him and see what he thinks. I agree with you, I feel like this definitely is not helping matters.

Is this the same (pardon the expression) trans guy that helped you R & R the broken flex plate and didn't notice that the bell housing was cobbed together from broken parts? Chances are the pump bushing failed because of the same misalignment that's breaking your flexplates. And where did all the material that wore off that busing go? I don't know of any transmission rebuilder that will use a welded or otherwise compromised housing. All things considered, I think you're headed for a rebuild, or just more problems if you don't.