Re: [DML] Re:Was Auto Trans Problems Now line pressure+vacuum

["Walter" <Whalt@xxxx>]

For measuring the line pressure, I bought the gauge from NAPA that DMC Joe
recommended. I checked the accuracy of the gauge and found it to be reading
0.2 Bar too high. So I pulled the glass off, pulled the needle off and then
stuck it back where it needed to be.

After I connected it to my DeLorean, I found that it would have been a LOT
easier if I had of threaded the gauge's hose through a hole in the frame in
front of the transmission instead of making the hose bend the corner as I
screwed it in.

I found that my pressure was exactly 8.0 Bar and needed no adjustment. It's
a good thing that I checked the gauge's accuracy before I started or I would
have made an uncalled-for adjustment to the transmission.

Other observations:

I found that transmission fluid temperature had no effect on pressure;
although, I was using Mobile pure synthetic @ $7 a quart. Maybe that stuff
is more stable than generic fluid. This always concerned me since I am
considering adding a separate transmission fluid cooler rather than relying
on the one coupled to the engine coolant line. If the fluid never comes up
to testing temperature, then how are you supposed to adjust it? Well, I
suppose it would be best to adjust it while at the temperature it will be
when you are using it the most, but temperature had no effect anyway.

At low RPMs with the gauge connected, I found that my car acquired an
unhealthy rattle. I was relieved to find that it was only the gauge's
needle bouncing to the rhythm of the fluid pump. I found that holding the
gauge to my ear made a great stethoscope to hear all the cool sounds that
the transmission made while it shifted. Okay, yes, I am weird!

When testing the car with the vacuum modulator line disconnected, I suggest
plugging the line with a shortened golf ball 'T' so that nothing gets sucked
up in there and so that the vacuum leak won't affect the engine. This is
probably unnecessary, but I've had loose vacuum lines clog from sucking in
globs of grease on other cars. That's something that's hard to diagnose on
some of these spaghetti bowl engines.

I have found that it is nearly impossible to get an accurate fluid level
reading because the fill port is the same place as the dip stick tube. If
you pour fluid down that tube, then forget about getting an accurate reading
on the stick until it all drains down -- say several hours. I just kept the
stick out of there and put a cork in the end of the tube until I was
satisfied with the fluid level. Otherwise, pulling the dip stick out the
first time to wipe off the slosh from driving would track oil through the
tube making a second reading difficult. The over-sized bass guitar string
stick does a lot to hold/smear fluid too. I'm considering drilling some
tiny holes through the end of the dip stick to make seeing the fluid level
more obvious. (Yeah, yeah -- me and cross-drilling! If it ain't my brake
rotors or Dave Stragand's brake lines, then I'm going to come up with a high
performance cross-drilled dip stick!)

If you over-fill the transmission while you have a gauge attached, I have
found that the hose on the end of the gauge is a lot easier to drain from
than loosening the fluid pan drain plug.

Despite over-filling and subsequent draining and re-filling to reach the
correct level, I found that I ended up with a net of 4.5 quarts of fluid to
re-fill my transmission. This seems like a lot since I only dropped the pan.
But I drained it hot and let it sit dripping for two weeks while I worked on
other projects. And after two weeks, it was still dripping!

Did I mention that I hate the smell of transmission fluid?

While you have the pan off, go to Radio Shack and buy a few of those high
energy rare earth magnets. Stick a few of those around the drain plug and
at the corners of the filter away from the inlet hole. The less metal
particles that circulate with the fluid, the better.

And if it blows up in your face or otherwise creates a liability, don't
blame me. I'm just an idiot/mad scientist. :)

Walt Tampa, FL