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Stock torque converter

jerrybromley

Full Member
Joined
Sep 17, 2018
Messages
344
I am in search of a stock torque converter . I purchased a used automatic setup for my 67. I discovered that I had the wrong converter when I tried to install it .The converter I got was simply too thick to fit.
I have been trying to find a stock converter that I know goes to the early bronco. I can't seem to locate one. Do any of you have a part number and source for a stock torque converter. I believe the tranny I have is a 73
 

DirtDonk

Contributor
Bronco Guru
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Nov 3, 2003
Messages
51,619
What flexplate are you using? Because it's a '73 the torque-converter it had is probably the larger diameter bolt pattern? Maybe? Either way, and no matter what, measure your flexplate-to-converter bolt pattern. Naturally there were two, and they're mixed up in the middle years (like '75/'76 or something like that?) but if you bought a new converter you probably have the easy-to-find pattern.

One good reason to know your pattern is that if you come up with a used converter you need to know what it fits. You can NOT buy a new flexplate in one of the patterns, so need to be careful what type of converter you source.

And offset plays a part in this equation as well. Are you certain that the flexplate has the correct offset? And are you sure the converter is too thick, or perhaps is just not seated fully into the transmission? Did you hear/feel the telltale three clunks when you inserted it?

Good luck.

paul
 

Rustytruck

Bronco Guru
Joined
Feb 24, 2002
Messages
10,872
what is the bolt pattern for the converter on the flex plate you are using? You will probably need a 1977 flex plate and converter. Your a contributer so post a couple pictures of what you are working with. that will help.
 
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jerrybromley

jerrybromley

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Sep 17, 2018
Messages
344
Thanks for responding ....The converter that was too thick was actually bottomed out against the tranny ( no clearance between transmission and converter on the transmission side ) and the converter studs would not clear the flex plate.
So I then found a rebuilt converter on E-bay ,it was considerably thinner and installed with no problem . but when I started her up the tranny would not engage . I am afraid that it might be too thin to engage the pump when the converter is pulled up to the flex plate . The stud pattern on the converters were both the 11 7/6" more common pattern.
The tranny is draining now and I will have it out today or tomorrow .
Big question now is....How do I know I have the right converter . I had no idea that this would be a problem
 

Rustytruck

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Feb 24, 2002
Messages
10,872
do a search on viperwolf1 on this site he has covered the C-4 in depth and has the information at hand for your needs. send him a private message he is active and responds.
 
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jerrybromley

jerrybromley

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Sep 17, 2018
Messages
344
converter confusion

OK I have the tranny out and have taken some measurements on the thickness of this converter. Here's a photo of how I measured it at 6 3/4 " If anyone has a converter that came out of a bronco sitting around I would really like to know if the measurement is the same.
There is also a photo of some numbers that were on the converter when I got it. I can't seem to find any cross reference to these numbers to let me know what the converter is made for.
The stud circle is 11 7/16" and the center hub is 2 "
 

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Madgyver

Bronco Madman
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Jul 30, 2001
Messages
15,030
what's the stall speed on a stock bronco torque converter? is it the same for all years?
 
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jerrybromley

jerrybromley

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Sep 17, 2018
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I have been reading that stock stall speeds are right around the 1800 range
 
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jerrybromley

jerrybromley

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Sep 17, 2018
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I did find an answer to the part number" F-28 "that was on the converter
According to http://www.tcsproducts.com/media/1/Converter_Cat1_1.pdf page 81
The converter goes to a 70-81 c-4 on 300 302 255 and 351 engines with a 26 spline
I don't see anything in the catalog that indicates the Broncos had anything different in them
So it appears I have the proper converter . I sure thought I had the converter pushed all the way in. I did notice That there did not appears to be hardly any fluid in the cooler lines . That would indicate to me the pump was not moving fluid...Maybe I didn't have the converter in properly....While I have it out any ideas what else to check to make this tranny engage ? :?
 
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Rustytruck

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Feb 24, 2002
Messages
10,872
when you put in the converter turn it as you push there should be 3 distinct clunks. when you bolt up the tranny the there should be a little space from the converter pads for the converter to pull up to the flex plate. the flex plate should not be pushing the converter in the tranny, the converter should pull up to the plate. if the pump is not lined up with the converter notches and you force the bell housing closed you can break the pump and will need to replace it. hope for no damage as you dive back in. Tranny takes more fluid that you think it will. there is not much margin for error just 1/2 quart low it wont work properly.
 
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jerrybromley

jerrybromley

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Sep 17, 2018
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344
Thanks for the advise Rustytruck, I'll bet I've put 20 trannys in and have never had a problem . Just because I'm in a rush to get my Bronco done this summer, it seems I screwed up...Damn! :mad:
 

rydog1130

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Jun 19, 2014
Messages
4,188
The C4 takes an ungodly amount of fluid if bone dry, I think i put 12 qts or more in mine...
 

tk1218

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Nov 23, 2008
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Loc.
Flower Mound
On your first post you mentioned that the original TC was too large for the bell housing. There is a large and small bell housing.
 
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jerrybromley

jerrybromley

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Sep 17, 2018
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344
On your first post you mentioned that the original TC was too large for the bell housing. There is a large and small bell housing.
The first T/C that I had came with the used automatic I bought to put in the 67. The diameter of the T/C was correct as was the bolt pattern . The T/C it's self was too thick . I believe now that T/C came from a C5 , because it was simply too thick
 

DonH

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Mar 8, 2013
Messages
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Loc.
WA State 30 miles from the beach
I bought from a freind a working C4 from a 1977 Bronco. It came complete with the original T/C. I installed the C4 in my 67 first than i installed the 289. There are larger holes next to the install holes on the flex plate. With the 289 and C4 pulled up tight the studs protruded through the larger flexplate holes. The T/C was free to turn back and forth in the larger holes but would not push back to clear the flexplate to get the studs into the mounting holes. I had to slide the engine back on the loosened engine bolts to get the T/C to turn into the flexplate holes. the engine bolts were retightened and the T/C studs were the tightened on the C4.
I have not installed a lot of auto trannies in rigs before but this was a new one for me.
 
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jerrybromley

jerrybromley

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Sep 17, 2018
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344
I bought from a freind a working C4 from a 1977 Bronco. It came complete with the original T/C. I installed the C4 in my 67 first than i installed the 289. There are larger holes next to the install holes on the flex plate. With the 289 and C4 pulled up tight the studs protruded through the larger flexplate holes. The T/C was free to turn back and forth in the larger holes but would not push back to clear the flexplate to get the studs into the mounting holes. I had to slide the engine back on the loosened engine bolts to get the T/C to turn into the flexplate holes. the engine bolts were retightened and the T/C studs were the tightened on the C4.
I have not installed a lot of auto trannies in rigs before but this was a new one for me.

Thanks DonH for the information.
I took some careful measurements with my dial caliper this afternoon and found some disturbing numbers...With the T/C fully engaged to the the pump I measured the gap between the bell housing mating surface to the base of the T/C stud at aprox. .450"
I then measured the the flex plate to the block ,through a bolt hole and came up with aprox. .650
It appears that the my T/C is too thick by .200 . I say its the T/C because my starter lines up fine with the flex plate. Either something is holding my T/C from completely seating or I may have the wrong T/C..... But the guy on E-Bay said it would work :eek:
 

brewchief

Sr. Member
Joined
Feb 11, 2007
Messages
877
The offset on a C-4 or AOD flexplate is different then a C-6 one, I don't know which way it's different or how much but it would be worth checking.

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