What 727 FRONT PUMP with a trans brake

Posted By: SCATPACK 1

What 727 FRONT PUMP with a trans brake - 09/29/10 12:56 AM

75 MODEL TRANS BEHIND A 572. Running a trans brake and it is a 75 model if it makes any difference. Is there preferred front pump to have when using a trans brake.
Just making sure I get the right one while I have the trans out for freshening.
THANKS

Posted By: SCATPACK 1

Re: What 727 FRONT PUMP with a trans brake - 09/29/10 04:13 AM

Anybody use a 727 any more???

Posted By: dartman366

Re: What 727 FRONT PUMP with a trans brake - 09/29/10 05:42 AM

just make sure your stock pump is in good shape clearance and spec wise, and better pump gears would be a plus, if for nothing other than peace of mind, I just broke the drive tang's off the gear in my 904 and I will be spending good money to make sure that don't happen again.

Posted By: SCATPACK 1

Re: What 727 FRONT PUMP with a trans brake - 09/29/10 01:56 PM

Quote:

just make sure your stock pump is in good shape clearance and spec wise, and better pump gears would be a plus, if for nothing other than peace of mind, I just broke the drive tang's off the gear in my 904 and I will be spending good money to make sure that don't happen again.

You earlier post is what got me to thinking about upgrading the front pump.
So is there any actual difference in front pumps and in the pump gears? Is there any difference internally in any of the pumps available? What should I be looking for in the pump or gears?

Thanks again for your knowledge and help

Posted By: dartman366

Re: What 727 FRONT PUMP with a trans brake - 09/29/10 02:09 PM

Quote:

Quote:

just make sure your stock pump is in good shape clearance and spec wise, and better pump gears would be a plus, if for nothing other than peace of mind, I just broke the drive tang's off the gear in my 904 and I will be spending good money to make sure that don't happen again.

You earlier post is what got me to thinking about upgrading the front pump.
So is there any actual difference in front pumps and in the pump gears? Is there any difference internally in any of the pumps available? What should I be looking for in the pump or gears?

Thanks again for your knowledge and help

I don't believe there is any difference in pumps with in year groups, I know there are some differences in internal oiling that prevent the interchange of certain parts, (mabey one of the guru's will verify this),,as far as the pump gears some have gotten away with stock replacement part's and some have had to go to the high dollar billet piece's, I am going with the billet parts cause I want to eliminate a weak link that cost me a weekend of racing.

Posted By: CRT

Re: What 727 FRONT PUMP with a trans brake - 09/29/10 06:20 PM

727 pump covers are the same. Early and late have differnt style vents , but thats it. Its the pump stators that are differnt.

62-66 uses a 19 spline input shaft and a narrow bushing on the front drum.

67-70 uses a 24 spline input shaft and a narrow bushing on the front drum. Both the 62-66 & the 67-70 you can not use a aftermarket billet front drum. As all billet drums use a wide bushing.

71-77 and 78 & up non lock up, uses a 24 spline input shaft and a wide bushing on the front drum, and can be used with billet front drums.
71-77 uses a 2 ring input shaft
78&up uses a 2 ring input shaft and 1 ring on the rear drum.

Posted By: 440Jim

Re: What 727 FRONT PUMP with a trans brake - 09/29/10 07:12 PM

Use a pump/stator support with the pressure passage to the front drum ported between the ring grooves. Many transbrake valve bodies have this in their instructions.

http://www.tciauto.com/Instructions/ResultsContent.aspx?query=121900
Step 4, illustration 3.
CRT sells modified pumps like this.
Modified Pump Supports enlarged 3rd gear oil feed. Machined on the gear side for trueness. 727PS-5 727 1971-78

And at least put new pump gears in to reduce the chance of fatigue cracking on the pump lugs. Or buy the HD ones.

Posted By: John_Kunkel

Re: What 727 FRONT PUMP with a trans brake - 09/29/10 08:00 PM

As part of an "Increased cooling package" the front pump was changed in '74, the most noticeable change is a reduction in the size of the cast counterbores in the pump housing and the reaction shaft support; this provides more seal off area for the face of the inner rotor.

At the same time the front clutch lube orifice in the reaction shaft support was eliminated, so a '74 and later pump has some good features and some bad (IMO).

I always drill the lube orifice when building a '74 or later 727, this requires an extension drill.

Also, it's important to keep the '74 and later input shaft with the like-year reaction shaft support as there are differences in the bushing lube ports.

Attached picture 6223350-71-73_vs_74-77support.jpg

Attached picture 6223350-71-73_vs_74-77support.jpg

Posted By: John_Kunkel

Re: What 727 FRONT PUMP with a trans brake - 09/29/10 08:04 PM

Counterbore differences

Attached picture 6223356-71-73_vs_74-77support2.jpg

Posted By: DamienH

Re: What 727 FRONT PUMP with a trans brake - 07/12/12 05:28 AM

I know this topic is a little old but I have a question John. I didn't know about the max cooling stator support change in 1974. I used an early front pump with the metal vent baffle but I'm not sure if I used a stator support with the max cooling changes or without the max cooling changes. I do know I used a wide bushings stator support. Is there a problem with using an early front pump with a max cooling stator support and vice versa.
Thank You

Posted By: John_Kunkel

Re: What 727 FRONT PUMP with a trans brake - 07/12/12 06:46 PM

It's not a good idea to mix parts, the combination of some supports and input shafts will eliminate lube in some areas.

Posted By: EFI DART

Re: What 727 FRONT PUMP with a trans brake - 01/01/21 12:11 AM

Hey all,
Can any of you guys please provide the matching photos on the input shafts , Stators and oil pumps ( WIde Bushing related only )\