Moved to Hudson forum category

Mark,

One method for changing the clutch fluid is:

Remove the pan below the flywheel. It is held on by two screws.
Rotate the flywheel until one of the two drain plugs is at the bottom.
Remove the drain plug (11/16 inch or 17 mm). You can collect the fluid that comes out, and measure how much came out.
The capacity is about 6 ounces.
Rotate the flywheel until the hole where the fluid came out is part way up, but where you can still reach it.
Using an oil squirt can, put 6 ounces of fluid into the hole.
Put the plug in and tighten it.
Re-attach the pan below the flywheel.

I use automatic transmission fluid. An elderly mechanic who remembered working on 1916 Hudson Super Six taxis provided the following formula: 1/3 gear oil. 1/3 #30 motor oil, 1/3 kerosene, and just a touch of Marvel Mystery oil! There are many opinions about what makes the best Hudson clutch fluid.

Another way, working just from above, is:

Rotate the engine until you can see one of the flywheel plugs through the window next to the starter.
Use a 3/8 drive 11/16 socket and appropriate extensions, to remove the plug.
Put a basin on the floor below the clutch.
Run the engine briefly. The fluid will come out of the clutch and dribble into the basin.
Move the flywheel until you see the hole where the fluid came out.
Get a hose about 18 inches long which is small enough to fit in the hole, and attach it to a funnel..
Insert the end of the hose into the hole in the flywheel.
While holding the end of the hose so it doesn't fall out of the hole (it helps to have a second person), pour 6 ounces of clutch fluid into the funnel.
Put the plug back into the flywheel and tighten it. It helps to put a piece of paper into the socket so the plug doesn't fall out.
If the plug falls down, remove the pan below the flywheel to get the plug.

Per

without to much thought, purchased 12 ounces from the HET store, should be good for the first go around. from many a read, most talk was to flush with kerosene, is that still the norm?

Mark,

If your clutch has been working properly, and some fluid came out, it doesn't need to be flushed. However, if no fluid came out, I think it would be a good idea to flush it. Kerosene should be fine. If the clutch was not working well, and some fluid came out, then a more aggressive flush might be best. I have used a 50-50 mixture of acetone and automatic transmission fluid.

Per

Per has pretty much summed up the correct process.

I could only add that a funnel with flexible hose will probably make the refilling process easy. Hold the funnel with one hand, insert the hose into the hole in the flywheel, and pour the Hudsonite with your other hand. [img ] [/img]

Incidentally, before removing the plug to insert the Hudsonite, you might want to stuff some rags into the space around the plug, in order to catch the plug, should you drop it. If you don't do that and you drop the plug, you will have to get under the car and remove the flywheel cover (2 bolts) to retrieve the plug. Adds about 5 minutes to the process, to do that.

I tried the second method for servicing my clutch, since that's the one documented in the Hudson mechanical procedures manual.  I must be missing something, because I found this truly impossible to do.  Here are the problems I ran into:

Getting the drain plug aligned with the opening next to the starter: How exactly does one "turn over the engine slowly"?  I have a 12 volt converted system with a proper 12v starter, and was unable to turn over the engine slowly. My first problem was that the button on my starter solenoid kept sticking, so the starter would keep turning.  I ordered and installed a new solenoid.  The button on the new solenoid misbehaved pretty much the same way.  So I made my own button with a reliable push button switch, but still could not get the engine to turn slow enough to find the drain plug.   

Nobody mentions that if you stand at the left fender and view the flywheel through the timing hole, you cannot see the plug because it is obscured by the timing pointer and the side of the housing.  You have to look at the hole pretty much dead on from the front of the car, which means leaning over the radiator while trying to crank the engine slowly, which is impossible with a 12v system.  If the engine is hot, you may burn yourself on the radiator.

Since using the starter was not working for me to turn over the engine slowly, I loosened all the spark plugs and turned the engine slowly by grabbing the fan blades.  This worked very well, and I was able to get a drain plug lined up with the timing hole.  The aforementioned timing pointer was in the way of getting an 11/16ths socket to go around the plug.  I removed the pointer. This is already ridiculous for a regular maintenance procedure.  

Nobody mentions that between dealing with the timing pointer blocking much of the heart-shaped hole through which access to the plug is supposed to be available, and the fact that a socket extender out of the hole (once the socket is around the plug) hits the engine where it juts out, so getting a socket wrench onto the extender with the socket around the plug is an exercise in futility.  My twin-h accelerate linkage gets in the way, and a little further out, my oil filter is in the way.  Do I also have to remove the oil filter? There is a small space between the oil filter and accelerator linkage, but it doesn't line up with the socket extender when the socket is around the drain plug.  My last resort in such situations is using a universal joint. I had no luck with that, either. I "only" spent 3 hours trying to get the socket on the plug with various extenders, with and without the u-joint attached, and the socket wrench attached with the handle in some location where I could conceivably turn it with enough leverage to loosen the plug without the socket falling off the plug.  No luck.

Nobody mentions that you either have to lie with your belly pressing into the left fender, or have arms like a gorilla and reach over the radiator, to reach the right spot.  I don't have 3 foot socket extenders.  Is that what I need? People who post that with the right set of tools you can do it need to actually describe what exact tools work for them.  Or, perhaps, do you guys have the tool Jxxxxx mentioned in the Hudson service manual for loosening the drain plug from above? 

Tomorrow I'm going to try getting at the plug from under the car by removing the clutch cover. It wasn't mentioned, but I assume I have to jack up the front end so I can get under the car to access what I need to get at. 

I thought the Hudson procedure for checking the brake master cylinder was the most difficult aspect of maintaining my car, until now. It appears to me that this wet clutch service procedure makes the 5,000 mile clutch service ridiculously difficult.  No wonder people complained about maintaining the wet clutch! 

Am I missing something here?

One way to move your flywheel from under the car is to use a flywheel turning tool which engages the flywheel teeth and let’s you crank it around by hand.  

I use a small mirror to see when the plug is in the “heart-shaped” window.  But you can also mark your flywheel so the drain plug is in the correct place to refill when your using the tool above from under the car. 

hope this helps

todd h

Success! My "technique" involved loosening all 6 spark plugs so I could turn the engine by hand, using the fan, and removing the pan under the flywheel from below after jacking the car up on jack stands, and a lot of "stretching" exercise going back and forth from underneath the car to standing in front of it.  I used a 2 oz syringe with a short piece of hose on the end to squirt the new clutch fluid into the filler hole, from below.  I had to move the filler hole up until it was barely reachable so the fluid didn't just come right back out.  2 oz of old fluid came out, and I put almost 6 oz back in.  The clutch chattering is much improved.  All in all, it was a success, but I hope I don't have to do it too often, because it's hardly convenient!

One more thing I'll mention: There is supposed to be a copper washer between each drain plug and the flywheel.  My car had a very old, distorted copper washer on one plug, and no washer at all on the other.  Now, it has new copper washers on both.  I hope that fixes the slow leak!

Very interesting discussion.  I suffered through a similar experience trying to change the clutch fluid on my '37. It had not been changed since I parked it in 1977.  The plugs were basically frozen onto the flywheel, and the solution was to use a lot of "Slick Stuff" lubricant.  I also bought a new 11/16 socket and sawed/ground off the outer 1/8 inch or so, so that the socket would sit flush against the flywheel.

Question, where does one get on of these flywheel turning tools?  Sounds like it would save a lot of work.

[b]I think I bought mine at Harbor Freight.[/b]

Do a search on eBay: “Flywheel Turning Tool”. Quite a few, new and old come up in the search.