904 trans help needed

gmonde · 08-29-2010, 06:15 PM

just built and installed 904 trans,,,,,heres the deal ,trans works great fast engagement from forward to reverse but have a serious leak from the bell housing (and of coarse you cant see any thing) change out the front pump seal from the new one that was installed new,checked pump alignment good ,when you load the converter it gets worse,,checked converter (brand new coan 5000 stall)welds look to be good but could be coming from there,,any one have to send a converter back because you cant locate a leak?any chance of the 904 early lock up case could be the issue not having a port exposed putting hight presure in the converter ??? i used the non lock up pump (two check ball pump) any input is helpful,,sending the converter back to have them presure test it

turbo action valvebody reverse manual
coan converter
aluminum front drum
turbo action rebuild kit

gmonde

Bill Harris · 08-29-2010, 09:05 PM

I had a converter do the exact same thing and it was a tiny pinhole in the weld. You could never see it with the naked eye. When you put some serious pressure in there, it's amazing how much fluid can come out of such a tiny hole. You should send it back to Coan and they should eat the cost!

GTX JOHN · 08-30-2010, 12:26 AM

Agree...sounds like converter or front pump problem. Check pump bushing for wear? dial indicate Hub for run out and pump shaft for being bent. Might be a local converter shop locally that could check it quickly and cheaply for you....usually not an expensive deal. Check crank end for right size pilot hole early mopars about 1.51 and late around 1.66 ( could tell you exactly after home from Indy ) could be wrong size making it misaligned or cocked slightly. Do not know AMC size. Good Luck

Ultimate Converter Concepts · 08-30-2010, 07:57 AM

Hi, check for a crack at the base of the slots on the drive side ( where the slot drives the pump lugs) It is a common problem with 904's and hard to see. Use a little fine polish on the hub in that area and the crack will show up.

Joe DeMarzo · 08-30-2010, 08:27 AM

This is why I love Lenny/Ultimate converters.....check the slots. Did you move to NC or AC? Garrett hope you find your issue and the trans is fast for you.

gmonde · 08-30-2010, 10:32 PM

update::: found the issue,,after pulling the trans for the third time ,i removed the front pump and looked closley at the small lubrication hole that are in the aluminum front drum,they line up with the vent holes on the back side of the pump,,this was filling up the vent and pushing out the front of the pump vent hole ,,so i tapped the hole and pluged it and redrilled the vent in the back of the case ,,loaded the converter hard and no leaks ,,got it down to 20 min to remove and 35 min to install ,,now we test and thanks for the input gmonde

08-29-2010, 06:15 PM	#1
gmonde Senior Member Join Date: Nov 2007 Posts: 615 Likes: 56 Liked 165 Times in 59 Posts	904 trans help needed just built and installed 904 trans,,,,,heres the deal ,trans works great fast engagement from forward to reverse but have a serious leak from the bell housing (and of coarse you cant see any thing) change out the front pump seal from the new one that was installed new,checked pump alignment good ,when you load the converter it gets worse,,checked converter (brand new coan 5000 stall)welds look to be good but could be coming from there,,any one have to send a converter back because you cant locate a leak?any chance of the 904 early lock up case could be the issue not having a port exposed putting hight presure in the converter ??? i used the non lock up pump (two check ball pump) any input is helpful,,sending the converter back to have them presure test it turbo action valvebody reverse manual coan converter aluminum front drum turbo action rebuild kit gmonde

08-29-2010, 09:05 PM	#2
Bill Harris Member Join Date: Mar 2002 Location: Ooltewah, TN Posts: 421 Likes: 13 Liked 26 Times in 13 Posts	Re: 904 trans help needed I had a converter do the exact same thing and it was a tiny pinhole in the weld. You could never see it with the naked eye. When you put some serious pressure in there, it's amazing how much fluid can come out of such a tiny hole. You should send it back to Coan and they should eat the cost! __________________ Bill Harris ex 2172 STK ex 2272 S/S

08-30-2010, 12:26 AM	#3
GTX JOHN VIP Member Join Date: Jun 2009 Location: Boulder City, Nevada 89005 Posts: 2,721 Likes: 2,772 Liked 2,440 Times in 689 Posts	Re: 904 trans help needed Agree...sounds like converter or front pump problem. Check pump bushing for wear? dial indicate Hub for run out and pump shaft for being bent. Might be a local converter shop locally that could check it quickly and cheaply for you....usually not an expensive deal. Check crank end for right size pilot hole early mopars about 1.51 and late around 1.66 ( could tell you exactly after home from Indy ) could be wrong size making it misaligned or cocked slightly. Do not know AMC size. Good Luck

08-30-2010, 07:57 AM	#4
Ultimate Converter Concepts Sponsor Join Date: Nov 2007 Location: Cornelius, N.C. Posts: 403 Likes: 6 Liked 59 Times in 12 Posts	Re: 904 trans help needed Hi, check for a crack at the base of the slots on the drive side ( where the slot drives the pump lugs) It is a common problem with 904's and hard to see. Use a little fine polish on the hub in that area and the crack will show up. __________________ Lenny Croteau www.ultimateconverter.com Phone 704-892-6837

08-30-2010, 08:27 AM	#5
Joe DeMarzo Senior Member Join Date: Oct 2002 Location: Mahopac, NY Posts: 666 Likes: 48 Liked 113 Times in 9 Posts	Re: 904 trans help needed This is why I love Lenny/Ultimate converters.....check the slots. Did you move to NC or AC? Garrett hope you find your issue and the trans is fast for you. __________________ Joe DeMarzo 1317 STK

08-30-2010, 10:32 PM	#6
gmonde Senior Member Join Date: Nov 2007 Posts: 615 Likes: 56 Liked 165 Times in 59 Posts	Re: 904 trans help needed update::: found the issue,,after pulling the trans for the third time ,i removed the front pump and looked closley at the small lubrication hole that are in the aluminum front drum,they line up with the vent holes on the back side of the pump,,this was filling up the vent and pushing out the front of the pump vent hole ,,so i tapped the hole and pluged it and redrilled the vent in the back of the case ,,loaded the converter hard and no leaks ,,got it down to 20 min to remove and 35 min to install ,,now we test and thanks for the input gmonde