Rebuilt 904. Whirring. Dead?

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frosty_the_punk

frosty_the_punk

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Hi guys.

I'm an aussie, I've just fitted a brand new 318 engine to my 1967 valiant with a rebuilt 904 behind it.

The trans has been tricked up to take horsepower with new steel planetaries, heavy duty low/reverse band. transgo shift kit and all the other junk I know nothing about.

The trans builder said he modified the transgo semi manual shift kit but couldn't get it quite perfect.

He also said he couldn't get a replacement valve body. and all I ever heard from him was "I can't get one of these. i can't get that"

Which i found to be ridiculous because you can get everything for a torqueflite and this is just for a basic 350hp 318.

The torque converter is a Continental 3000RPM stall. it was also serviced at the same time as the transmission.

I put 4 Litres of fluid in the trans before i broke-in the cam in last night. and everything appeared optimistic as the engine runs sweet as a nut.

Nothing had leaked over night.



Today I drove the car just so I could get the car out of one shed to the other which has a hoist (200m away) for final checks and adjustments.

I rolled it back and forward twice in D and R to make sure It had motivation from the trans. It moved fine with the RPMs at a smidge above idle. I drove like this for about 30 seconds total before getting to a hill.

at that point I felt the revs drop with the load of the hill so I touched the throttle ever so slightly and something in the trans let go. :eek:ops:

It revved up and made a sound like "WHIIIIRRRRRRRRRRRRR".

The car started to roll backwards down the hill and the whirring sound was still there.

So I switched the ignition off and It was still making the noise even without the motor running as it rolled backwards.

After jacking the car up and checking the starter motor pinion. I discovered it was NOT binding on the ring gear at all.

I called the trans guy who built my trans and he suggested putting more fluid in the trans. I added an additional 2 litres which made no difference at all. and then another 2 litres with no difference at all.

This brings the total up to 8 litres of fluid.

With the engine running it makes the whirring sound in every gear except reverse.

starting it in reverse it has motivation but seems to clunk and put excessive load on the engine as it drives.

Starting it in drive has no motivation and makes the very prominent "whirrrr" noise that matches the engine RPM, as it does in park or neutal.



So I'd like your opinions.

What do you suspect might be the problem with my trans and how might it be fixed?

Is this my fault for not using enough trans fluid? or was it bad workmanship by the trans that caused this problem?

I am going to put a stock torque converter and stock 40+ year old transmission in the car just to get it running again while i sort out this other trans. because I'm sure that the problem is internal.

Look forward to hearing what you guys have to say on the topic.

I know there's some guys on here who know their torqueflites inside out, upside down and and backwards.

Thanks, Frosty.


PS. sorry for the super long post.
 
Sorry to hear about your trans. Which Trans-go kit did he install? TF-2? Why do you say that he modified it? I'm sure that Tracy Aka Fishy68 or one of the other transmission guys will chime in soon.
 
Thanks Badart.

yeah, I'm not too sure why he modified the valvebody, he seemed to think he would be able to get it to shift a little "nicer" but said he wasn't 100% happy with it.

It was the transgo one. TF2 I think. which ever one is the semi manual one. It was in the transmission when I bought it.

I'm thinking I would like to put in a standard valvebody and see if the components in the trans communicate better after that.
 
Just for the sake of knowing ... Check if the bolts through the flex plate are too long and made dimples in the torque converter. It's happened before.
 
Hi RedFish.

It's not the torque converter bolts as the engine was spinning over freely when breaking-in the camshaft.

also when towing or pushing the car either backwards or forwards, with engine turned off the whirring noise is there.

The torque converter, trans and starter are all from the same car and were working fine with each other for the last owner, I saw it with my own eyes.
 
the sound is similar to this.

[ame="http://www.youtube.com/watch?v=rVWcvxxtJtk"]Torqueflite whine (in N) - YouTube[/ame]
 
I think it would have to be in the torque converter or front pump.
The 904 in our old 73 Valiant made a whirlly noise its whole life, 308 K miles. Worst sound inside the car was sort of a lew lew lew lew through 1st gear. Trans tech at the Ford store where I worked said it was the front pump and it would eventually wear out the front case.
Good luck with it.
 
Thanks guys.

I think one of these days I'd love to learn to built my own torqueflite.

I am going to put the standard 40+ year old trans and converter in the car just to run the motor in gently

Then once it's gotten a few hundred km on it, I'll take the car and and broken trans to the trans shop and ask him to repair and refit it.

that way it will be his responsibility to make sure it works properly, not mine.

If anyone else has any more opinions or advice I'd be interested hear.
 
A whirring sound like that is generally an internal leak. Either a blown clutch pack seal or converter problem but your statement that it does it with the engine shut off and you just pushing or towing the car would seem to rule out the torque converter because it isn't doing anything unless the engine is running. To tell you the truth unless your trans. is an older model with a rear pump I don't know how it could possibly make any noise with the engine shut off. I'd first check the rear differential. Jack the car up and put it on stands and spin the wheels and listen where the noise is actually coming from. If you can't tell by spinning it by hand start it up and run it through the gears. Yanking the converter out and replacing it without any diagnosing is not the proper way to do things.
 
Thanks fishy68.

The noise is not coming from the rear differential. It sounds like it's coming from the rear half of the transmission.

I have had the rear on stands and the rear diff is behaving normally.


The whirring sound when being towed is less noisy than when the engine is running. When it's being towed it sounds more like a ratchet than a whirring.

if you get a ratchet spanner and grab it by the socket and let the handle spin around and round, it sounds kinda like that when being towed.

Like one perpetual barrage of clicks that sound almost constant.

you have to listen for it but it's unmistakably there. especially if it picks a little bit of speed up (like 5MPH)


When it's running I can't really hear the engine much, mostly the whirring drowns it out. the exhaust is a twin 2" system with front and rear mufflers.

Whatever is making the whirring sound is putting enough load on the engine to make it stall at idle in any gear except reverse (including park and neutral).


I have very little knowledge on torqueflites but to my knowledge this one is not one able to be roll started. So I think that means it doesn't have a rear pump.


I know it's not ideal to swap another trans back in before diagnosing the problem on this one.

however there's no way I'm giving my car to the transmission shop with an engine that's not run in yet.

it only ran for 25-30 minutes and has never even had any load on it yet.

Would it help if I took a video of the car's symptoms? Whirring etc.
 
If it makes an noise when you push it,i think you may have a problem with the roller sprag on the rear.Jack the rear up and take it out of park the spin the drive shaft clockwise then counter clockwise there should be resistance in one direction.:blob:
 
frosty_the_punk said:
Thanks guys.

I think one of these days I'd love to learn to built my own torqueflite.

I am going to put the standard 40+ year old trans and converter in the car just to run the motor in gently
Click to expand...

Be sure to flush the cooler several times if you do this. If something let go, there's probably debris in the cooler.

Take it apart yourself. The 727/904 are as simple as they get!
 
BRONZEBEE said:
If it makes an noise when you push it,i think you may have a problem with the roller sprag on the rear.Jack the rear up and take it out of park the spin the drive shaft clockwise then counter clockwise there should be resistance in one direction.:blob:
Click to expand...

Could be the springs and rollers weren't put back in there right or something?? If the noise is indeed coming from the back of the trans. After 65 or 66 they did away with the rear pump in the torqueflite, so that's the only culprit that I could think of as well.
If it's coming from the front....prob the front pump gears were really worn and not replaced and chattering/vibrating in the housing.
Hopefully it's found out quick for you....good luck!!

Oh, i agree...727/904 easiest as they come!
 
frosty_the_punk said:
Thanks fishy68.

The noise is not coming from the rear differential. It sounds like it's coming from the rear half of the transmission.

I have had the rear on stands and the rear diff is behaving normally.


The whirring sound when being towed is less noisy than when the engine is running. When it's being towed it sounds more like a ratchet than a whirring.

if you get a ratchet spanner and grab it by the socket and let the handle spin around and round, it sounds kinda like that when being towed.

Like one perpetual barrage of clicks that sound almost constant.

you have to listen for it but it's unmistakably there. especially if it picks a little bit of speed up (like 5MPH)


When it's running I can't really hear the engine much, mostly the whirring drowns it out. the exhaust is a twin 2" system with front and rear mufflers.

Whatever is making the whirring sound is putting enough load on the engine to make it stall at idle in any gear except reverse (including park and neutral).


I have very little knowledge on torqueflites but to my knowledge this one is not one able to be roll started. So I think that means it doesn't have a rear pump.


I know it's not ideal to swap another trans back in before diagnosing the problem on this one.

however there's no way I'm giving my car to the transmission shop with an engine that's not run in yet.

it only ran for 25-30 minutes and has never even had any load on it yet.

Would it help if I took a video of the car's symptoms? Whirring etc.
Click to expand...

Ok, I don't blame you for not taking it there with a fresh engine. A video might be of help if you can get good audio. As mentioned, there is very little in the back that can cause a noise like that. The sprague clutch being one and if there is a problem with it I can see it putting a load on the engine in either drive or reverse but I don't know how it could put a load on the engine in park and neutral because none of the clutch packs are energized in P and N so no power should be going back there. One other item in the back that could cause a noise like that is if something went wrong with the parking pawl assy such as it not releasing all the way but just like the sprague it shouldn't cause a problem in park and neutral since no power is going back there. See if you can get a video of the sound and how it bogs down the engine. Do it with it up on jack stands so you can also get under the car with the camera. We might be able to hear it better that way.
 
j5dart said:
Sounds to me like the front planet blew up.
Click to expand...

DING! DING! I bet we got a winner there. The front planetary is directly attached to the output shaft and is locked stationary in reverse so a broken one would do all those things. In my 30 yrs. of rebuilding TF's I've never actually saw one break but I've heard they do. Good thinking j5. Have you saw that happen very often?
 
Hey guys. I will get the video up in the next week or so. as I'm going away to australia's biggest mopar show. "Chryslers on the Murray" this weekend (without my car unfortunately).

I had the car in park when I ran the cam in.

from memory. with the wheels jacked up the parking pawl seems to be engaging properly when I shift it from reverse into park. (motor turned off). I don't think i checked the other gears but i plan to.

I will have to check everything over properly and write down the cause and effect of everything so that it will help with diagnosing the problem.

I think I will have to let the trans guy see the problem and then remove the trans. once it's removed I will take the car away and put my other trans back in at home.
 
i agree with j5. ive only rebuilt a couple of 727s and so far no problem with em. since you said you have a shift kit in it and possibly a stage 2 id be careful when it shifts cause i have a reenginering kit in my truck and my duster. when i got my truck back the shifts were hard enough to hit my head on the window but yet my duster doesnt shift as hard and ive done all sorts of lil tricks my boss knows to get firmer shifts. but i would look at both sets of planets. pump wont do any harm if you installed the converter all the way in
 
Thanks man. My convertor was set inside the trans by the trans builder and held in with a piece of aluminium flat bar. I simply removed the flat bar and installed the trans/torque converter to the motor/flexplate.

i used all new bolts etc. nothing was snagging or rubbing anywhere.

I never had it out of first gear so I don't know how well it shifted if at all lol.

Does anyone know what the possible cause for a front planetary failing could be?

Would it be very likely that it would be caused by running at 5-10mph for 30 seconds with low fluid level?

Or is it more likely either a faulty/worn component or a mistake during assembly?

or is it hard to accurately say?

Thanks again guys.
 
Planetaries generally fail because of metal fatigue but running too much horsepower/torque through them can also strip/break them. The builder should have inspected the planetaries for cracks and wear. Not pointing the finger at him but if that is what happened it seems odd that it failed so quickly especially since you didn't even take it out and jump on it. You should have had the trans. in neutral when you broke the cam in because torqueflites don't pump fluid in park (unless a modified manual valve is installed). I can't imagine that would hurt the planetary gear set(s) but it could have scored other parts from lack of lubrication. As for shifting too hard I wouldn't worry about that unless the builder screwed something up but I gotta say that 1st off Trans-go does not sell a "semi manual" shift improver kit. They sell the TF-1, and TF-2 kits which are shift improver kits but they retain fully automatic shifting. The only other kit they have is the TF-3 kit which is full manual shift. And to say he couldn't get it quite perfect doesn't make a lick of sense. To install any of the Trans-go kits it's just a matter of disassembling the valve body, changing a couple springs, drilling 3 or 4 passages, removing a check ball (TF-1 and 2 kits only), possibly eliminating a spring in the front servo, and grinding the throttle pressure valve. Maybe a couple other minor things I'm forgetting but nothing major. I haven't done a TF-3 kit so I'm not sure what is required of it.

Have fun at the Mopar fest.
 
Thanks fishy68.

The trans had new steel planetaries installed. So I'd say it's unlikely they've failed due to prior wear. I think it's more likely a manufacturing defect or human error in assembly.

I am fairly sure the shift kit was a Transgo TF-II as the car it was in before mine was a street vehicle that shifted automatically.

Next time I run a camshaft in I will make sure the trans is in neutral instead of park.
 
fishy68 said:
Planetaries generally fail because of metal fatigue but running too much horsepower/torque through them can also strip/break them. The builder should have inspected the planetaries for cracks and wear. Not pointing the finger at him but if that is what happened it seems odd that it failed so quickly especially since you didn't even take it out and jump on it. You should have had the trans. in neutral when you broke the cam in because torqueflites don't pump fluid in park (unless a modified manual valve is installed). I can't imagine that would hurt the planetary gear set(s) but it could have scored other parts from lack of lubrication. As for shifting too hard I wouldn't worry about that unless the builder screwed something up but I gotta say that 1st off Trans-go does not sell a "semi manual" shift improver kit. They sell the TF-1, and TF-2 kits which are shift improver kits but they retain fully automatic shifting. The only other kit they have is the TF-3 kit which is full manual shift. And to say he couldn't get it quite perfect doesn't make a lick of sense. To install any of the Trans-go kits it's just a matter of disassembling the valve body, changing a couple springs, drilling 3 or 4 passages, removing a check ball (TF-1 and 2 kits only), possibly eliminating a spring in the front servo, and grinding the throttle pressure valve. Maybe a couple other minor things I'm forgetting but nothing major. I haven't done a TF-3 kit so I'm not sure what is required of it.

Have fun at the Mopar fest.
Click to expand...

not to brag but the pump is always pumping fluid as long as the converter is spinning. but theres a possible chance that is was a human error or a defect or the builder lied and said he put new ones in and put the old ones in
 
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