Down the rabbit hole ...

[Don Frelier]

I've never had a converter fail.
But that said; my friend down the road had a custom made converter that he used to race break off a small piece.
Just small enough to plug the cooler supply line.
By the time is started to smell the damage was done.
He had to do a full rebuild on that transmission.

 

[Curiousyellow71]

The fluid through the convertor is filtered. As to whether I would reuse the convertor??.. there are certainly cases that I would not. Such as If the fluid was black...and the tranny was completely toast.
but...If the fluid color looks decent and you lost one gear but it was operating fine in the other gears...I have no problem putting it back in if the seal and bearing area are not grooved. Since the convertor did not fail, no reason you can't use it again.
From what was described...I would reuse it if it were mine. Convertors are hard to flush, do your best.
If you need a new convertor you need one with the same weights...that is assuming it had the correct convertor for the engine.

 

[Skytrooper]

So, if it does have crud in it...can it be flushed out ? It does have a drain plug. I am just spitballing here. On one hand if the TQ is good, why buy another ? Conversely, if it is bad...I don't want to ruin a new rebuild.

 

[Skytrooper]

If you need a new convertor you need one with the same weights...that is assuming it had the correct convertor for the engine. From the picture it looks to be a externally balanced engine and it's likely not for a 71.

I was under the impression that a 1971 440 HP is externally balanced. This is the original engine. The transmission is from a 1968

 

[Curiousyellow71]

If it has a drain plug you can do a decent job flushing it. The only reason I can think there would be crud in it is if the convertor or pump failed. It doesn't sound like either did. Pull the plug flush it and make a judgment call.
A hp w HD rods probably would be externally balanced, Likely what you have.

a 68 convertor would be internally balanced as would a lower hp 71 440 with standard rods.

 

[Lefty71]

So, if it does have crud in it...can it be flushed out ?

Yes, a trans shop or converter manufacturer can flush it. But, for a basic unit, as others have said, you may not want to risk it. One tidbit to note... if it were a warrantee job from a new Ford at a Ford dealer and the trans failed, the valve body and the oil cooler would not be reused due to contamination or debris, but the converter would if were not suspect.

 

[Lefty71]

Original '71 440's would ALL be forged cranks, even the 335hp motors.... Look at the damper or send us a pic... Harmonic Dampers 440 Source.com

 

[Skytrooper]

This is the damper I have on my car
damper #3512017,
Courtesy of 440 source.com:
Shown above is damper #3512017, commonly known as a "six-pack" damper. This damper can be easily identified by a small .210" thousandths thick elliptical weight attached to the center hub. This version was used in '70 and '71 and has the offset pulley bolt pattern. Be careful not to confuse it with 3614372, which was used only in '72 and looks similar except for having a symmetrical pulley bolt pattern. The weight on the 3614372 may be slightly thicker at .255", but we have not been able to verify this.

Even though these dampers have an elliptical weight, they were never used with any cast cranks. These dampers were used with steel cranks and "six pack" (2951908 casting #) rods. The extra weight is to offset the added weight of the extra metal in the rods and pistons. Another important fact is that even though six pack rods continued to be used up until 1975 in HP and truck 440's with steel cranks, they did NOT use this damper. As you can see from the chart above, any 73-75 steel crank 440 (with either six pack or standard rods) would have come with the 3614371 damper. We have found this to be absolutely true.

 

[Lefty71]

This is the damper I have on my car
damper #3512017,
Courtesy of 440 source.com:
Shown above is damper #3512017, commonly known as a "six-pack" damper.

Right!! So, if that's the case, that's no cast crank motor. If your converter is original to the car, then that weight setup should be duplicated exactly, I do believe. If it's not original, then we need to solve the mystery of what to use. Maybe some folks who have had six-pack original and magnum-440's with six pack rods will chime in.

 

[Skytrooper]

I hope so !!! We are close to solving this mystery, I believe !!

 

[Photon440]

Yes, a trans shop or converter manufacturer can flush it. But, for a basic unit, as others have said, you may not want to risk it. One tidbit to note... if it were a warrantee job from a new Ford at a Ford dealer and the trans failed, the valve body and the oil cooler would not be reused due to contamination or debris, but the converter would if were not suspect.

The valve body could be completely dis-assembled and cleaned out, why not use it again if no scoring was evident in the sliding valves?

 

[Curiousyellow71]

You have a unique torque convertor for the heavy 6 pack rods. I am sure somebody out there can do a convertor with the right weights but I don't know of anything over the affordable counter.

This is a list for flywheel balance weight options for a manual transmission. Automatics would share the same balancing. My suggestion.. Do your best to reuse your convertor...its your best option. Neutral balanced will vibrate and cast crank convertor is similar but not correct.once upon a time they made a flex plate to overcome it...but I think it's been discontinued..and it would add to your cost

 

[Don Frelier]

Did you ever decode the VIN on that car?
Because it has a 4 barrel intake on it today.

 

[Skytrooper]

U code 440 magnum 4bbl. It was never a six pack car but the 71 440hp motors had the heavy components. According to everything I have been reading.

 

[Don Frelier]

Well nothings ever been easy on that car, no reason this should be any different.
After reading the posts here I think you should stick with the converter you have.

 

[Skytrooper]

Well, when I drain it...I will find out if it is a keeper or not. I read a bunch of articles on flushing with mineral spirits. I think kerosene would be safer, but it doesn't really evaporate. Hmmm....more reading is in my future.

 

[HawkRod]

Well, when I drain it...I will find out if it is a keeper or not. I read a bunch of articles on flushing with mineral spirits. I think kerosene would be safer, but it doesn't really evaporate. Hmmm....more reading is in my future.

Why not just flush it with ATF? With your drain plug, you should be able to fill, swish it around and then drain it as needed. When you see clean ATF coming out, you are done. Using ATF, you won't care how much is left, and it certainly won't harm the rest of your transmission.

 

[Cranky]

I have all the same issues. I had to remove the headers to remove mini starter and to gain clearance to the transmission. They will NOT be going back on ! I bought some log manifolds that will work much better for access to things like the starter and spark plugs. I just finished sandblasting them yesterday and applied 3 coats of VHT Flameproof ceramic manifold paint. I think they look pretty nice. Cost me a whopping $75 + paint.

View attachment 1209037

Look at that, I hijacked my own thread !

LOL! Believe it or not, had a 71 340 Cuda with the Hooker Super Comps on it and the factory style 'short' starter would come out without unbolting the header but had to hold my mouth just right and stick my elbow up my butt to do it lol. There was only one way that it would come out and it was snug doing it.

View attachment 1209120
This is the damper I have on my car
damper #3512017,
Courtesy of 440 source.com:
Shown above is damper #3512017, commonly known as a "six-pack" damper. This damper can be easily identified by a small .210" thousandths thick elliptical weight attached to the center hub. This version was used in '70 and '71 and has the offset pulley bolt pattern. Be careful not to confuse it with 3614372, which was used only in '72 and looks similar except for having a symmetrical pulley bolt pattern. The weight on the 3614372 may be slightly thicker at .255", but we have not been able to verify this.

Even though these dampers have an elliptical weight, they were never used with any cast cranks. These dampers were used with steel cranks and "six pack" (2951908 casting #) rods. The extra weight is to offset the added weight of the extra metal in the rods and pistons. Another important fact is that even though six pack rods continued to be used up until 1975 in HP and truck 440's with steel cranks, they did NOT use this damper. As you can see from the chart above, any 73-75 steel crank 440 (with either six pack or standard rods) would have come with the 3614371 damper. We have found this to be absolutely true.

Had a 70 Challenger 440 RT that had the same balancer but never had the trans out so can't add any info on the converter weights if any. Did the car vibrate any at all in neutral sitting still and bringing up the rpm? If it was out of balance, you would feel it well before 3500 rpm.

Well, when I drain it...I will find out if it is a keeper or not. I read a bunch of articles on flushing with mineral spirits. I think kerosene would be safer, but it doesn't really evaporate. Hmmm....more reading is in my future.

After using mineral spirits for about 5 years now....I hate the crap! Another member mentioned using trans fluid to flush it and I vote on that! I suppose you could flush it using that or kero then flushing that out using ATF.....

 

[Skytrooper]

UPDATE

I drained the TC today (first chance since getting back in town). The fluid came out looking like new. No sludge, black streaks, or foreign debris. I flushed it twice and still nice clean fluid. I am going to continue using it. Transmission is done, but I have to save some money so I can pay for it (Christmas airfare).
So far, so good !

 

[HawkRod]

UPDATE

I drained the TC today (first chance since getting back in town). The fluid came out looking like new. No sludge, black streaks, or foreign debris. I flushed it twice and still nice clean fluid. I am going to continue using it. Transmission is done, but I have to save some money so I can pay for it (Christmas airfare).
So far, so good !

I would do the same.