Packard Forum Index » V-8 (1955-56)

The engine was removed from my '55 Patrician. This vehicle came with a rebuilt engine and trans but the direct drive clutch has not been working from day one. With a pressure gauge I confirmed the clutch hydraulic pressure was kicking on at governed speed but no actuation.

Anyway, while removing the engine it was discovered the converter to flywheel nuts were all loose. However, the real problem is the converter will not separate from the flywheel. It's still attached to the engine and prying on it won't dislodge it from the flywheel. Any ideas?

So just the converter is on flywheel/crankshaft?

If so. Well must be stick in crankshaft. If so . need to get a pry bar between flywheel and converter.

Use some type of lube . just be careful not to bend flywheel.

Converter is hanging on to the back of the engine. The mechanic says he's used prybars but was afraid to pry any harder for fear of damaging the flywheel.

Yes, the pilot diameter of the convertor is stuck in the counterbore on the back of the crank. If you are talking 49-54 you can remove the bolts and then force the convertor to spin in the counterbore till it comes out. If you are talking 55-56 the studs hinder rotation but they are loose enough in their holes that you can get a very slight back and forth rotation to help break it free. Otherwise you just have to pry it off and get another flexplate afterwards if the old one will not indicate true.

Got the converter removed. The center bore on the crank was rusty and they had rusted together. Now to disassemble and see if I can figure out why the direct drive clutch isn't working. I'm assuming I can just invert and remove the clutch side cover without tearing everything down through the turbines, then disassemble the clutch from the cover.

Converters are balanced and while many are taken apart haphazardly it is a good idea to punch or somehow mark the edges of the converter halves so you can bolt them back together the same way.

That I'm aware of, but while I'll be checking the clutch friction plate (I have a new one, btw), that the piston isn't seized and the ring gaps are staggered, one thing I don't know is the hydraulic path to the piston. I'd like to blow it backwards to ensure it's not plugged with something. I assume I'll find a port behind the piston.

The end of a port which gets the DD pressure from the valve body goes thru the front pump and then thru either a combination of gaps in bushings, shafts or thru a gap between rotor teeth finally ending at a hole in the side of the input shaft. The exact route thru the pump depends on parts combinations. The input shaft is bored down the middle and that passage ends behind the DD piston. Pressure goes thru the various gaps and spaces at the pump, forward thru the input shaft and exits at the DD piston.

When the DD clutch comes in to take the load there is not much need for the turbines so when the clutch applies, the oil circulation inside the converter pump and turbines is reduced allowing the piston to more easily move. To release the DD clutch the pressure behind the piston is dropped and simultaneously the fluid under some pressure begins to start circulating thru the converter again. The loss of pressure behind the piston and the increased flow in the converter pushes the piston back freeing the clutch plate.

Before you take the converter apart you might check first to see if your transmission has had the front pump or rotors replaced and might be one where the combination of new pump rotors and the existing converter pump shaft was one where a restriction in the path to apply DD pressure might occur. There was a service article outlining a particular combination of parts that needed some extra work done if it was put into service.packardinfo.com/xoops/html/downloads/SC/SC-VOL30NO5.pdf

Interesting. Thanks for the info. The transmission was rebuilt but I have no idea what specifically was done. If this part mismatch were to have occurred, would the DD hydraulic pressure on the side port of the transmission still kick on at governed speed with normal pressure? That test did pass.

As Howard mentions the path to the direct clutch is rather complicated in the 49-55 trannies, much less so in the 56s.

If someone substituted a 56 front pump in your 55 there will be a port missing. The valve body will send pressure to the the direct clutch, but there is no way for it to get there.

Will try to find a picture when I get back to the shop.