[adventureseeker]

Ok, Let's make a long story short:
Under heavy acceleration, I heard a clunk and lost all power, and I heard a whining noise when the engine was Idling, in all gears and park. This was on my baby, an 84 GMC Caballero (Gmc's El Camino). The engine is less than a year old, as well as the torque converter and Transmission (Turbo 350). I ended up replacing the stock transmission with a street/strip transmission from Jeg's, which failed after 4 months. Here I am 4 Months later, so I assumed that it was the transmission again, so I ordered B&M's street/strip Turbo 350 and just finished installing it. Lo and behold, still whining and no go.

Here are my questions:

1) Engine runs fine and I have a just-out-of-the-box transmission, so I guess the torque converter went bad (TCI Saturday Night Special). Is this a correct assessment?

2) Assuming that it is the Torque Converter, what should I replace it with? This is my everyday driver, but I still want to GO! I replaced the stock 305 engine with a Crate 350, but there is no Cam shaft mod...which converter is best for my application?

3) I have also read that because I ran a bad torque converter (supposedly) that I need a new Transmission because I could have metal shavings in it from a bad converter...is this true, or can I just flush everything out really well? This Transmission has ZERO miles on it.

Any suggestions would be greatly appreciated.
-tired of changing transmissions, and just want my baby back-

 

[Triaged]

I would like to complement you on a good first post. You organized the post well, gave just the right amount of background info, and were to the point with your questions. :thumbup: Welcome aboard :welcome:

I have only rebuilt 1 auto trans (a th350) so I am not the expert that some on here are. But I think I can at least ask some good questions and maybe give some tips on what I would do.

-Is the trans full of fluid? Sounds like a lame question but my truck took over 12-quarts of ATF before it would go into gear.

-When you installed the torque converter did you feel/hear all 3 clunks as the different parts were engaging?

-How much did you have to pull the torque converter away from the trans to bolt it to the flex-plate?

-What did the fluid look like in the old trans (the one that lasted 4 months)? Was there any "sludge" in the pan after you took it off?

-Is the flex-plate in 1 piece? When I rebuilt my trans the flex-plate had a crack 3/4 of the way around it (sorry...another very stupid question that I'm sure you would have checked/noticed).

 

[Rob Keller]

WELCOME TO HOTRODDER'S :welcome: :welcome: :welcome:
om not sure if i read you right did you not change the converter?
was there metal in the old tranny?
the converter has to be all the way back when properly installed you CAN NOT slip you fingers behind it in between the bell housing and converter
i learned that the hard way.

sr66 :thumbup:

 

[adventureseeker]

To answer the questions asked of me:

Triaged:

1) I hoped that I had misread the dipstick, but to my dismay, It read full.
2) I did not hear anything but a whine after I installed the Torque converter.
3) I believe that I had to pull the Torque Converter about an inch.
4) I did not notice any sludge, and the fluid was still cherry red (less than 3K mi)
5)I did not see any cracks, but I will check it out tomorrow.

Rob Keller:

1) I did not change the Torque Converter yet, that is the job for tomorrow. I assumed that since the last transmission I got went out, the latest one I had installed went out as well, since they were re-manned by the same people. Only after I started my car up did I realize that the problem must be the Torque Converter.
2) When installing the Converter, the TH350 will not marry to my engine unless the grooves on the Torque Converter's shaft are properly aligned, otherwise, the converter gets in the way of the engine to transmission bolts. After the engine and transmission are married, I then slid the Torque Converter forward to the flexplate(about an inch, I believe)

Thanks for your time and inquiries, as well as the warm welcomes to Hotrodders.com. The chance that I got two bum transmissions are astronomical, and at this point, I just hope that it is the Torque Converter. Any more help would be greatly appreciated.

 

[topfuel]

Adventureseeker you should only have to pull the converter out about 1/4 to 3/8" to meet the flex plate. If you are truly pulling it out an inch, the converter may be barely engaging the front pump and under hard acceleration, the flex plate may be "flexing" too much and the converter might have disengaged from the front pump, hence no power. If necessary you can install spacers between the mounting pad of the converter and the flex plate or try to find another flex plate with taller mounting points.

I hope this helps. :thumbup:

 

[adventureseeker]

Upon inspection, the torque converter only has about 1/4 inch play between flexplate and the Transmission. When looking for a torque converter, I want to go with a stock converter, but I am having problems picking one out. I had a Saturday Night Special torque Converter, but I think it's shot. i swapped the trigonal 305 for a crate 350 and when I took out the stock transmission (turbo 350), it had a 4 pin (I believe) electrical connection on the driver's side, right on top of the pan, slightly forward of the Speedometer cable. Through research, I think that this is the TH350C, made for a lockup converter. When going to the Parts store, they try to sell me a lockup converter, but my new Transmission does not have the electrical connections.

1) Can anyone explain Lockup converters to me? The Converter that just went out was a stall converter (around 1900 RPM.)

2) Which converter would be best for my application? I have a fairly stock 350 ci. and a B&M street strip transmission, with the stock 2.74 rear end. This is my daily driver, but I still want some punch in it.

3) Anyone know of an 84 Chevy vehicle that came stock with a 350/turbo 350, non-lockup converter? This would make finding parts easier.

-Thanx-

 

[tresi]

Did you replace or have the convertor flushed when you replace the transmission? if not it probaby contaminated the new transmission with junk from the failed transmission.

 

[adventureseeker]

When I got the B&M Tranny in, it called for Type F fluid, so I flushed the torque converter and cooler lines with Type F. I called B&M to make sure that this was not a misprint, but they said that Type F gives firmer shifts, as opposed to Dextron. Why did a torque converter from a reputable company fail after less than a year of less than strenuous use?

 

[Triaged]

I don't think your converter is toast. I think it just isn't engaged into the pump like someone else said. The drive slots on the converter are only about a 1/4" deep. When you moved the converter about 1/4" away from the trans to bolt it to the flexplate it caused it do become disengaged (or engaged but so little that it would slip off).

You said that the fluid from the old converter is clean and that you did flush the trans cooler and converter as best you could so I don't think that is the problem.

Unbolt the converter from the flexplate and put some washers (some nice flat machine washeres would be good but make sure that they are all 3 the same thickness at least). You should be able to do this without haveing to pull the trans out and if it works will be able to drive it to work on monday so that is what I would try first.

 

[adventureseeker]

The only thing that keeps me from writing it off as an install mistake on the Torque converter is that it ran fine since January, and have had no problems before now. This was not the first time that I put my foot into it. Another thing that comes to mind is that I was sure that I put in the converter right, because if the grooves on the Torque converter do not match up with the keys in the Transmission shaft, there is not enough clearance for the transmission to bolt up to the engine, AND I heard the 3 clicks that I am supposed to hear when the converter goes on. I am putting in a stock converter on Tuesday. If that doesn't work....what are the chances that a new B&M Transmission is a lemon???

 

[adtkart]

Keep in mind that the parts that you are speaking about are man made. That means that there are always possibilities of error.

Usually a whine in an automatic trans is either from the pump or the convertor. The way I understand your posts, you used the same convertor in each trans that didn't work, and they are doing the same thing To me that is an indication that the convertor is the problem. The convertor can fail and not turn the fluid dark. Usually it will have a metalic look to it. There will be metal shavings on the pan when it is removed. If that is the case, there is a high likelyhood that the same stuff has been put in the new trans. The correct way to correct that problem at this point is to replac the convertor and dismantle the trans, check everything, clean everything, and reassemble. There is a high likelyhood of a considerable amount of metal shavings in the valvebody.

Good Luck