Hi Guest!
Hey - did you know if you click on the title of a thread it will take you to the first unread post since you last visited that thread?
but were afraid to ask: 
STOP!! Never post your email address in open forums. Bots can "harvest" your email! If you must share your email use a Private Message or use the 
smilie in place of the real @
Pretty Please - add it to our Events forum(s) and add to the calendar! >> 
thomaslea1
Freshman Member
Offline
I'm posting this everywhere I can in hopes SOMEONE will be able to shed some light on it.
*****************************************
Have a 68MGB w/1980 blue label OD. Unit works perfect from cold start-up to somewhere in the 30 to 50 mile range. When it gets to full operating temp it begins to drop out on it's own.
What I have done:
1) I pulled everything from the bottom. Sprayed every available passage way with carb cleaner,
2) The pump is clean, unscored and tight and has very good suction when operated against my skin.
3) There were some issues with the relief valve spring. Couldn't buy a new spring by itself, so I sprung for the new valve assembly.
4) When I finally got to my wits end I ASSUMED that the solenoid coil was breaking down under heat. So I replaced it.
5) Obviously, while doing all this, a new filter screen.
6) To eliminate the switches I bypassed the 4th lock-out and installed a new toggle switch in place of the gearshift lever switch.
7) I've tried almost every type of 'recommended' oil. It's currently running 20W-50.
One last thing:
When it's hot and the OD kicks out I can: Take it to about 50MPH - switch the OD in and coast - RPM drops like it's in OD - but accelerate and have no OD.
BUT: if I accelerate to 50MPH - switch the OD in and coast - RPM drops like it's in OD - then (without accelerating) switch it out - I can feel it engage into non-OD mode and the RPM's come back up.
***********************************
Attached a pressure gauge today. At cold start (about 80F) the OD produced 440 PSI. The farther I drove it and the warmer it got, the lower the pressure dropped. When I got about 15 miles the pressure at 55MPH and 2,500 RPM was a little less that 325PSI. Coming home I started out with the engine temp higher, and at the end of the 13 miles the pressure at 55MPH and 2,500 RPM was closer to 300PSI.
ALL the O-Rings in the lower end are new. The solenoid and ball are new and the ball was seated. The pressure relief valve is new, as well as a new non-return valve kit in the pump.
Where do I go from here????????????
As far as I can surmise, the only things left that I can get to from underneath are the pump body ($43), the pump plunger ($80) and the pump spring ($11).
The only other place I can see where fluid would by-pass would be the 45 cent piston O-Rings, but I have to disassemble the unit to replace them.
*****************************************
Have a 68MGB w/1980 blue label OD. Unit works perfect from cold start-up to somewhere in the 30 to 50 mile range. When it gets to full operating temp it begins to drop out on it's own.
What I have done:
1) I pulled everything from the bottom. Sprayed every available passage way with carb cleaner,
2) The pump is clean, unscored and tight and has very good suction when operated against my skin.
3) There were some issues with the relief valve spring. Couldn't buy a new spring by itself, so I sprung for the new valve assembly.
4) When I finally got to my wits end I ASSUMED that the solenoid coil was breaking down under heat. So I replaced it.
5) Obviously, while doing all this, a new filter screen.
6) To eliminate the switches I bypassed the 4th lock-out and installed a new toggle switch in place of the gearshift lever switch.
7) I've tried almost every type of 'recommended' oil. It's currently running 20W-50.
One last thing:
When it's hot and the OD kicks out I can: Take it to about 50MPH - switch the OD in and coast - RPM drops like it's in OD - but accelerate and have no OD.
BUT: if I accelerate to 50MPH - switch the OD in and coast - RPM drops like it's in OD - then (without accelerating) switch it out - I can feel it engage into non-OD mode and the RPM's come back up.
***********************************
Attached a pressure gauge today. At cold start (about 80F) the OD produced 440 PSI. The farther I drove it and the warmer it got, the lower the pressure dropped. When I got about 15 miles the pressure at 55MPH and 2,500 RPM was a little less that 325PSI. Coming home I started out with the engine temp higher, and at the end of the 13 miles the pressure at 55MPH and 2,500 RPM was closer to 300PSI.
ALL the O-Rings in the lower end are new. The solenoid and ball are new and the ball was seated. The pressure relief valve is new, as well as a new non-return valve kit in the pump.
Where do I go from here????????????
As far as I can surmise, the only things left that I can get to from underneath are the pump body ($43), the pump plunger ($80) and the pump spring ($11).
The only other place I can see where fluid would by-pass would be the 45 cent piston O-Rings, but I have to disassemble the unit to replace them.
