Listers,
This write up was faxed to me by Carl Sereda who recieved it from someone
else on the list. I would like to thank both of them for providing the info.
I could be wrong but I would think that this same information would apply
to the D-type and the J-type OD's as well.
Below is the write up reproduced exactly as it was sent to me. Any typos
were probably added by me however!!
=====
It is possible to "bench test" a transmission with an A-type overdrive and
insure the overdrive mechanicals are functioning, before the unit is
installed in the car. I ALWAYS do this before installing an OD tranny. It is
easy to do, and is much preferred to discovering a mechanical problem after
the tranny is installed.
You'll need, of course, the assembled tranny with the overdrive; a 1/2"
chuck drill (the higher RPM, the better); and a functional tachometer or
speedometer with drive cable.
First fill the transmission with the recommended grade of oil. By the way,
the OD manufacturer Laycock recommends SAE 30 whilst the car manuals
usually call for SAE 90! I usually run SAE 50. Chuck the 1/2" drill to the
transmission input shaft. Screw the tachometer/speedometer to a drive
cable - any length will do - and screw the other end of the cable to the
speedo drive on the tranny.
With the tranny full of oil you're ready to test the overdrive. First make
sure the tranny IS NOT IN REVERSE! Engage any of the forward gears 1
thru 4 and turn the transmission with the drill. There should be some kind
of reading on the tach/speedo when this is done. Note this reading. Now
with the drill turning the tranny over, engage the overdrive manually by
rotating the operating lever clockwise. This is the little lever mounted to
the operating shaft, on the side opposite where the solenoid goes. It will
have a small hole in the end which when aligned with a similar hole in the
side of the OD should engage the overdrive. A 12% lower reading should
result on the tach/speedo when the overdrive is engaged.
Actually I usually dispense with the gauge when performing this test,
having found that in first gear it is easy to discern the change in the pitch
of the whine the drill makes when the OD is engaged. Since the reduction
is a simple ratio, first gear gives the most change in RPM.
If you have a battery laying about you can use this setup to adjust the
solenoid operating lever and make sure it actually works. I have found a
few instances when simply aligning the holes in the operating lever and OD
block was not sufficient to engage the unit. You can also wire up the
inhibitor switches and insure they work too.
Brad (Lincoln Nebraska 402-464-1502)
1964 Spitfire4 BFC25720L
1966 TR4A CT72398L (Now a parts car)
1961 TR4 CT288L (Now with OD!!)
1959 TR3 TS41311L (Rusting Hulk)
1951 Dodge Truck 82217766 B-3-B-108
|