Convertor hub wear/front seal leak

[john.thompson068]

I bought a brand new PTC converter and put it in a newly rebuilt transmission. The transmission leaked from the front seal from day one. I drove the car less than 1500 miles and have since pulled the transmission for a new front seal.

The front seal cost me $100 and they had my transmission for over three weeks. The transmission guy first said this was the best converter he had ever seen and mentioned that the welds are the best he had ever noticed. Then he later tells me the wear marks on the hub indicate the converter is bad and the wear marks indicate an off center hub which is wearing away at the seal and causing the leak. He pointed out how the wear marks are high on one side and then low on the other side. He also said there should not be a groove felt in the hub and pointed out the burrs around the bottom of the hub as being a sign of poor quality control.

One thing I did not do when I installed the converter the first time was grease up the seal and the hub and this may have damaged the seal before transmission fluid was able to begin lubricating the seal. However, the first builder may have greased up the seal as I noticed this builder applied grease to the seal.

I have attached a picture of the new seal, and there is also a picture of the rear of the motor which was also rebuilt at the same time as the transmission. I have also attached pictures showing a 360 degree look at the converter hub. On one side of the hub I can feel a slight groove on the wear marks but the other side is perfectly smooth.

Is this converter hub wear normal? Is the groove felt by running my finger up and down the hub normal?

 

[Cranky]

Kinda hard to tell from the pics but it doesn't look bad to me. Generally, the hub is machined after being welded evidenced by most of the weld being machined smooth. I doubt it's out of alignment but the case alignment to the block might not be true. That's a common thing. Serious racers and builders will indicate the case before putting anything in it. It's a pita but then you know what you have.

 

[Meep-Meep]

I'll agree with Cranky that it appears to be pretty normal wear. I had a seal leak on me with a new converter and a rebuilt tranny. The tranny sat for a long time but never ran since being rebuilt and it turned out the old pump seal was not very flexible so I put in a new seal and that was that. Lot of cussing was involved on that job :angryfire:

 

[Meep-Meep]

Oh, I just noticed the washers under the flex plate bolts. In my experience those are too soft and tend to squish out before you can get a good torque on the bolts. Just FYI.

 

[mikebee]

i would check or have the converter checked..it could have been welded off center....that would be more likely than block to trans casing being off.ptc is a good converter but any one can make a mistake.that will also cause vibrations.....no more than that is probly not much tho......also i never put any kind of washers on the flexplate bolts.

 

[john.thompson068]

If it still leaks I will have the converter checked and another seal put in. I am currently reinstalling the trans. I talked to Tim at PTC and he said the wear I described sounds normal and he recommended putting the converter back in and seeing what happens with a new seal. He said to grease up the seal and hub and not let the converter hang on the end of the shaft which could stretch out the seal.

I was having trouble getting the converter in and I let go of it while it was just barely penetrating through the seal. I took note of the amount of free play it had in this position and then was able to get the converter all the way in the transmission. I wiggled the converter around once all the way in and it had the same amount of free play so I cannot believe that letting go of the converter before it is all the way in would affect the condition of the seal. Anyway, I figured out that the big splines and the small ones have to be aligned before it will go in so next time I will not have as many problems.

Also, I left the washers on the flex plate because I am sure they came with the flex plate in addition to the bolts. I did check to make sure the bolts were still at 55 ft lbs of tq and they were still tight.

I will post here in a few weeks, since I am doing other work to the car also, about whether it is still leaking. It was a significant leak before and would result in a cloud of smoke coming off the exhaust after high speeds.

 

[Cranky]

i would check or have the converter checked..it could have been welded off center....that would be more likely than block to trans casing being off.ptc is a good converter but any one can make a mistake.that will also cause vibrations.....no more than that is probly not much tho......also i never put any kind of washers on the flexplate bolts.

I've checked a lot of bell housings and automatic transmission cases over the years and you might be surprised at how many that are not in alignment.

If it still leaks I will have the converter checked and another seal put in. I am currently reinstalling the trans. I talked to Tim at PTC and he said the wear I described sounds normal and he recommended putting the converter back in and seeing what happens with a new seal. He said to grease up the seal and hub and not let the converter hang on the end of the shaft which could stretch out the seal.

I was having trouble getting the converter in and I let go of it while it was just barely penetrating through the seal. I took note of the amount of free play it had in this position and then was able to get the converter all the way in the transmission. I wiggled the converter around once all the way in and it had the same amount of free play so I cannot believe that letting go of the converter before it is all the way in would affect the condition of the seal. Anyway, I figured out that the big splines and the small ones have to be aligned before it will go in so next time I will not have as many problems.

Also, I left the washers on the flex plate because I am sure they came with the flex plate in addition to the bolts. I did check to make sure the bolts were still at 55 ft lbs of tq and they were still tight.

I will post here in a few weeks, since I am doing other work to the car also, about whether it is still leaking. It was a significant leak before and would result in a cloud of smoke coming off the exhaust after high speeds.

The washers on the flexplate are probably ok but they did not come from the factory with any but they had Loctite. Also, make sure your converter bolt lugs are in the same plane. Generally, it's not a big issue if they are not totally exact but they should be pretty close at least. Check them with a flexplate that you know is flat...