Help-Powerglide-big leak when on the brake?

cad · 07-07-2014, 10:10 AM

Hi all,
Over the last couple of weeks, my glide has developed a leak. The case is OEM GM. We thought it was the pan gasket, but have now ruled that out. It is dry above the pan rail on the sides and front. It is only wet on the rear/driver side of the trans. Enough that the trans blanket and cross member are soaked after a run.

Testing with the front wheels up on the trailer tail gate, it is leaking when running and the transbrake is engaged. We swapped solenoids and no better. Since it was leaking, we didnt race and drove it into the trailer and I drove home. It did not leak in the trailer and nothing in garage after driving it from the trailer to the garage.

Trans was rebuilt before the season. It just started leaking about the 4th race into the season. I know that the solenoid has not been over tightened, but it is almost like the solenoid boss is cracked.

Just looking for any experiences that you've learned.
Thanks
Clark

SSGN · 07-07-2014, 11:23 AM

Vent plugged or leak coming from the vent? Lots of guys running overflow cans today. I run one on my street car because it will leak out the vent on hot days when tranny temp gets up there.

Kevin

Rick Shirey · 07-07-2014, 12:08 PM

Hate to be the bearer of bad news but if it only leaks with the t-brake is applied the most likely cause is the case is cracked in the reverse clutch pack area. The OEM cases are weak in that area.

Rick Schilling · 07-07-2014, 12:10 PM

I did not have a trans brake, but I had a similar issue a number of years ago with a glide. I had a stream of fluid hitting the left side header every time I put the car in reverse. That turned out to be a leak at a casting seam near the rear of the trans case. I had it welded a couple of times but only managed to redirect the stream each time, never stop it. Had to re-case the trans to correct the problem.

cad · 07-07-2014, 12:59 PM

Thanks for the replies. It's not coming from the vent. Trans was rebuilt and vent is new (and still clean)...I wish it was that easy. It has a blanket and nothing is wet up front/down the sides.

I am going to clean it up tonite, add dye and check it with a black light. We put an Ultrabell on last year and I figure it's time for the Ultracase. The car is now running 6.60s and the case is the last weak link (for now).

Clark

SGSST109E · 07-07-2014, 01:08 PM

The OEM cases crack right on the parting line for the casting in the rear clutch area.

Alan Roehrich · 07-07-2014, 06:17 PM

Quote:

Originally Posted by Rick Shirey

Hate to be the bearer of bad news but if it only leaks with the t-brake is applied the most likely cause is the case is cracked in the reverse clutch pack area. The OEM cases are weak in that area.

^^^^^^^^^^^^^^^^^^^^^
This, seen it dozens of times. Often caused by chassis flex, mount problems, or in a dragster, tire shake.

ss3011 · 07-07-2014, 08:31 PM

Seems strange that the case should fail at that seam line. What line pressure do you run in Rev, and when the Trans Brake is on? Maybe the pressure is too high and stresses the case.

cad · 07-07-2014, 10:49 PM

Dye immediately showed when on the brake. dont know what pressure it is set at. Since the ultracase isnt available in time for a 3 race weekend, I ordered a 1 pc sfi glide case and have the trans pulled. Appt made with my trans guy for wed night if fedex shows up on time. He will swap everything over while I wait for $100. Ultrabell will be for sale...lol. dated dec 2013 I believe.

Pedigo Perf · 07-08-2014, 07:29 AM

Check the driveshaft for run-out (before you pull the transmission back out) and get it balanced if you have time. I had an off center pinion yoke that was causing run-out and it killed 2 cases for me before I fixed the issue.

07-07-2014, 10:10 AM	#1
cad Senior Member Join Date: Apr 2009 Location: Omaha, NE Posts: 703 Likes: 203 Liked 93 Times in 52 Posts	Help-Powerglide-big leak when on the brake? Hi all, Over the last couple of weeks, my glide has developed a leak. The case is OEM GM. We thought it was the pan gasket, but have now ruled that out. It is dry above the pan rail on the sides and front. It is only wet on the rear/driver side of the trans. Enough that the trans blanket and cross member are soaked after a run. Testing with the front wheels up on the trailer tail gate, it is leaking when running and the transbrake is engaged. We swapped solenoids and no better. Since it was leaking, we didnt race and drove it into the trailer and I drove home. It did not leak in the trailer and nothing in garage after driving it from the trailer to the garage. Trans was rebuilt before the season. It just started leaking about the 4th race into the season. I know that the solenoid has not been over tightened, but it is almost like the solenoid boss is cracked. Just looking for any experiences that you've learned. Thanks Clark

07-07-2014, 11:23 AM	#2
SSGN Senior Member Join Date: Feb 2006 Posts: 647 Likes: 132 Liked 140 Times in 51 Posts	Re: Help-Powerglide-big leak when on the brake? Vent plugged or leak coming from the vent? Lots of guys running overflow cans today. I run one on my street car because it will leak out the vent on hot days when tranny temp gets up there. Kevin

07-07-2014, 12:08 PM	#3
Rick Shirey Junior Member Join Date: Apr 2003 Posts: 53 Likes: 0 Liked 0 Times in 0 Posts	Re: Help-Powerglide-big leak when on the brake? Hate to be the bearer of bad news but if it only leaks with the t-brake is applied the most likely cause is the case is cracked in the reverse clutch pack area. The OEM cases are weak in that area.

07-07-2014, 12:10 PM	#4
Rick Schilling Member Join Date: Feb 2009 Location: Indy Posts: 103 Likes: 18 Liked 14 Times in 10 Posts	Re: Help-Powerglide-big leak when on the brake? I did not have a trans brake, but I had a similar issue a number of years ago with a glide. I had a stream of fluid hitting the left side header every time I put the car in reverse. That turned out to be a leak at a casting seam near the rear of the trans case. I had it welded a couple of times but only managed to redirect the stream each time, never stop it. Had to re-case the trans to correct the problem.

07-07-2014, 12:59 PM	#5
cad Senior Member Join Date: Apr 2009 Location: Omaha, NE Posts: 703 Likes: 203 Liked 93 Times in 52 Posts	Re: Help-Powerglide-big leak when on the brake? Thanks for the replies. It's not coming from the vent. Trans was rebuilt and vent is new (and still clean)...I wish it was that easy. It has a blanket and nothing is wet up front/down the sides. I am going to clean it up tonite, add dye and check it with a black light. We put an Ultrabell on last year and I figure it's time for the Ultracase. The car is now running 6.60s and the case is the last weak link (for now). Clark

07-07-2014, 01:08 PM	#6
SGSST109E Member Join Date: Jun 2007 Location: NJ Posts: 351 Likes: 62 Liked 126 Times in 61 Posts	Re: Help-Powerglide-big leak when on the brake? The OEM cases crack right on the parting line for the casting in the rear clutch area.

07-07-2014, 08:31 PM	#8
ss3011 Senior Member Join Date: Feb 2002 Location: Southeast Michigan Posts: 909 Likes: 70 Liked 239 Times in 114 Posts	Re: Help-Powerglide-big leak when on the brake? Seems strange that the case should fail at that seam line. What line pressure do you run in Rev, and when the Trans Brake is on? Maybe the pressure is too high and stresses the case.

07-07-2014, 10:49 PM	#9
cad Senior Member Join Date: Apr 2009 Location: Omaha, NE Posts: 703 Likes: 203 Liked 93 Times in 52 Posts	Re: Help-Powerglide-big leak when on the brake? Dye immediately showed when on the brake. dont know what pressure it is set at. Since the ultracase isnt available in time for a 3 race weekend, I ordered a 1 pc sfi glide case and have the trans pulled. Appt made with my trans guy for wed night if fedex shows up on time. He will swap everything over while I wait for $100. Ultrabell will be for sale...lol. dated dec 2013 I believe.

07-08-2014, 07:29 AM	#10
Pedigo Perf Member Join Date: Feb 2008 Location: Wichita Ks Posts: 383 Likes: 70 Liked 30 Times in 17 Posts	Re: Help-Powerglide-big leak when on the brake? Check the driveshaft for run-out (before you pull the transmission back out) and get it balanced if you have time. I had an off center pinion yoke that was causing run-out and it killed 2 cases for me before I fixed the issue.