question on transmission line cooler hose

[spstan]

Does anyone know the pressure of the fluid in a transmission line cooler hose under operating conditions (in psi)? Reason is I'm trying to patch a transmission line in my 1975 New Yorker with 727 transmission. I'm debating on whether to use a cooler hose with 2 clamps on each end or a steel line patch with compression union on each end.

Also what is best way to find the leak? I'm thinking driving for a little bit and placing cardboard under lines to find the drips. Paul

 

[413]

Cooler pressure is quoted as 5-30psi in the shop manual. It will leak immediately on start up so don't go drive, it will just spread all over in bigger area.

Clean and wrap the line with a paper towel and the leak will show itself quickly.

 

[Sixpactogo]

I don't know what the running pressure is on the cooler lines but it is not high pressure that would blow a hose clamp off IMO. As far as a 727, they do tend to leak in a few places. One of the most popular places is at the kick down linkage lever. The best way to find the leak is to clean all the oil off as best you can then after a few hours you should be able to locate if it is above the pan gasket. Good Luck.

 

[1970FuryConv]

Does anyone know the pressure of the fluid in a transmission line cooler hose under operating conditions (in psi)? Reason is I'm trying to patch a transmission line in my 1975 New Yorker with 727 transmission. I'm debating on whether to use a cooler hose with 2 clamps on each end or a steel line patch with compression union on each end.

Also what is best way to find the leak? I'm thinking driving for a little bit and placing cardboard under lines to find the drips. Paul

I have used transmission oil cooler hose and clamps, but only after I flared the ends of the line on both sides of the area that I cut out. Without flaring the ends of the lines, you will continue to have a leak.
Also, if the hose will be near an exhaust pipe, I would use a heat shielding wrap or use steel line and compression fittings. Another option is to cut the original line farther from the exhaust and bend new line for the side of the line that needs to be extended.