If it was me ,1 I would drop the oil pan.Then check the oil filter and pick up to make sure it is not sucking air.remove the valve body and clean it and the valves with paint thinner(when the valve body is taken off it has I think 2 small ball valves that can fall out)so lower it down carefully and look where thay come from so as to put them back in the proper place.allso take photos or make notes as to how and where the valves fit,thay have to go back in the same holes and turned the same(end wise)as thay came out.
2 it could also be the rings in the accumulator wore out
3 could also be the governor sticking or dammaged.

Brent, I am not a Hydramatic mechanic, but this problem should be something that Gus Souza could help you with. A call to Gus is the best way to sort our questions, but with you being in New Zealand a letter or email would more than likely be the best method of communications. Gus lives in Illinous and is listed in the roster... possibly you can find the information here.

Make sure you have the lever in 4 if it's a dual htdro. I think you need to adjust the shift rod to make sure it's in 4 then 3. If it's a single range that was a problem they were having, depends on gas pedal pressure. Walt.

What happens if you disconnect the throttle pressure rod completely?. This isn't something you leave off,but if it will upshift and stay??,look at the throttle pressure rod arm that goes into the trans. These are stripped alot of times because they were not adjusted correctly. Once the spline gets stripped, the trans will be all over the place when shifting up and down. Good luck Doug

Something I should add,if you take the rod off of the bell crank at the engine block,you should be able to push it back with a little pressure and it should stop then pull it forward with a little pressure and see if it will connect back into the same postition without pulling it too hard. This sounds kind of difficult,but it will usually let you determine if it is moving inside the trans. If it is stripped,the throttle pressure is running uncontrolable and causes real erractic upshifts and downshifts.PROBLEMS

Hi thanks to those who replied, I will drop the covers and check the items listed. If I need to I am going to change the unit, do I need to take the floor out inside the car. I have the wasp body and the fire wall is pretty close to the engine/gearbox. ie are the bolts removable from the top with the floor in?

Thanks again Brent

Hi Brent, All I have seen have heavily"gooped" access ports
for the bell housing bolts.

Good Luck!

Fred "Ric"

Brent,

If you have the short wheelbase car (WASP) and want to take the floor out, you probably have to remove the heater box/fan first, assuming your car is equipped with that. Then, once you've moved the floor covering out of the way, you'll see that the entire large center section will come out easily by removing something like 20 bolts. You should remove your seat cushion so you don't damage or soil it when you take the floor out. Here's a picture of my 1950 Pacemaker (SWB) with the floor out. The Hydramatic is probably a little larger than the standard 3speed with OD like mine, but you should be able to access it fairly easily. The other picture shows mostly the dash, but the heater box/fan is installed as well as the floor.

Brent, if you plan to change the trans,what tools do you have at your disposal?. If you have a lift and transmission jack,this job is much easier. Starting in '51,there is no need to remove the front floor pan,but just remove the access panels which Ric pointed out,and of course,all the torus cover bolts. Make sure that you drain the torus bowl,as described in the shop manual before starting to remove any bolts. If you don't,you will be working in a pool of fluid-what a mess it will make.. As Tim pointed out,if you don't have these items availible,you will need to jack the car up and secure it safely,drain all the fluid from the torus bowl as well as the 7/8th's plug in the trans.oil pan. Remove the front floor pan and figure out how to lift that heavy piece of iron out of the hole or drag out from under there. Some Hydramatics have a 7/16th's-14 threaded hole in the top of them,which you can screw an eyelet into and lift it out. Also,read the shop manual on this procedure to help yourself identify what your doing. I hope this helps, hudsonly Doug

Shift linkage is your problem. Make sure it goes to 4th gear all the way. another problem is bad motor mounts on the left side, front and rear mount. Walt.