clutch release problem

[R.White]

I am having difficulty in engaging gears either stationary or on the move. Double de-clutching does not work even with the engine revs adjusted down and I have changed the oil to 680w (steam cylinder oil). I Have removed the clutch inspection cover and established that with the clutch pedal depressed I am able to move all the driven plates back and forth quite freely on the flywheel pins and the pressure plate spins freely. If I start the engne and depress the pedal, the pressure plate continues to spin with the clutch plates. If I try to select a gear it will only stop the pressure plate after a few attempts and gear grinding noises. If I then select neutral and lift off the pedal, the pressure plate starts spinning again. I have sprayed the clutch plates with clutch cleaner.

What is the best course of action? Is there a problem with the clutch throwout? Exactly what needs to be replaced/repaired to allow a crunch free gear change?

I am really relying on you guys to help me get this sorted and I appreciate any advice that can finally get this great old Dodge Brothers car back on the road.

Ray.

[Pete K.]

Ray, It doesn't sound like your clutch throwout bearing is bad, "they" usually stop working by giving a really bad noise at first, when pedal is depressed followed by complete failure when the balls fall out from the worn off bearing retainer. From what I gather, the transmission gears are spinning with even low engine rpm's and clutch depressed. Either the 680W oil isn't up full enough to just cover the reverse idler gear, or the pilot bearing on the forward end of the trans. input shaft is seized. I don't recall seeing a pilot bearing seize that strongly to keep the transmission shaft turning that much. A sticky build up of goo could have got on the clutch plates, like you say you were spraying them down with carb cleaner. Maybe not all the goo got sprayed off. They HAVE to be dried out after spraying them.

[R.White]

Thanks for those ideas, Pete. The problem as I see it is that if the plates were sticking, how is it that I can move them freely with my fingers? That is why I am scratching my head.. The pressure plate starts rotating again when I put it in neutral. Could the plates be warped? The new oil is 4 pints - exactly as the manual says for this transmission. The throwout makes a noise. The original grease tube had been leaking badly but I had hoped with a new tube (on order from Myers) some lubrication might improve things. I guess that without removing the transmission, I am not going to find out what is wrong, unless it is something silly like not enough throw on the throwout bearing. I have always known them as a "thrust release" bearing. Same thing, I suppose.

[Pete K.]

I've had some old cars with noisy release bearings too, It's still in one piece and doing it's job. Yours definitely needs some lube soon. I have not had my '25 transmission opened up beyond the point of the top cover, so I'm having a hard time figuring this one out. I want to say the slight warp-age, if any, with the plates would not be so pronounced as to spin that group of plates that soon after stepping on the clutch pedal. You could back off the pedal adjustment quite a bit just to see if that changes things, then remember to re-adjust for proper pedal play. You could also jack up the drive wheel at rear and put trans. in reverse gear,with engine running, to see if the plates slow or stop when you push the clutch in.

[R.White]

I reckon you might be onto something with the pilot bearing, Pete. There are not too many options left if you rule out sticking plates and the throw out bearing. Something is causing the clutch to drag when the pedal is down and the gear is shifted into neutral - when stationary!

Without lifting the pedal, if you select neutral, you can see the plates start right off spinning again; when the darn things should stay put to allow you to select a gear. Forget the warped plates theory, like you say it's not likely.

The pedal may have been adjusted wrong - but then how would I be able to move the plates about freely by hand when they are at rest? ....Curious.

Of course, I do not know if the transmission and clutch have been tampered with in the past and maybe have some vital part missing. That would not surprise me. I also wonder if there is a wear pattern which could lead to this sympton.?

Ray.

[R.White]

I have removed the leaking grease pipe from the throwout bearing carrier and fitted a zerk. I pumped some grease in directly but it has made no difference to the problem. I guess I didn't really think it would.

The clutch plates are not gummed up; with the pedal depressed I can easily move them apart on the flywheel pins but when I start up the engine the pressure plate will only stop spinning with a gear selected and the pedal depressed. As soon as I select neutral with the pedal still down, the pressure plate starts revolving quickly again - making it impossible to change gear without a lot of noise. Double declutching makes no difference.

Should the problem be the pilot bearing, has anyone had the experience of replacing it and what is involved?

The workshop manual is rather short on help in this area.

Ray

[brian1925tourer]

Hi my names Brian and I am from melbourne Australia, I have a 25er and my clutch does the same as yours, at first when cold I wobble the shifter and select the gear usually reverse and not too much trouble there, as I'm driving going up in gears no prob's at all. When things are warm and stopped at lights I have to go through the motion while stopped of into 3rd then 2nd to get first to avoid too much crunching. Sometimes it just drops straight in and makes me look like I know what I'm doing. I recently took my car for a 90 klm drive thats an hour each way, and although there were moments of crunching all went well. I have very thick oil in gearbox and have dropped idle down as low as possible. If your car is similar to mine I would leave it alone there is no syncro so there will always be a bit of crunching. I hope I have helped in some way and if you do find a solution let me know. I could do with some tips of how to gear down to 2nd without breaking something. regards Brian

[R.White]

It's good to hear from you Brian. Please forgive me the indulgence; but I am an inveterate tinkerer and will not rest until I have at least established whether or not I can fix this problem. These non synchromesh straight cut gears do have their limitations but it should be possible to change up or down, if not at will, then with a little persistance. I am failing to achieve a change of gear; period. Having tackled some tricky gearboxes in vintage cars over the years, I am sure there is something wrong rather than anything that could be explained by my rather impetuous nature.

Although I have rebuilt several gearboxes, I am not an expert and I am hoping to hear from someone who has rebuilt a '20's Dodge Brothers transmission with the same problem so that I may be saved the frustration of making the same mistakes which others may have learned from in the past.

One device which has been used in cases of "difficult" transmissions is a clutch brake. If need be I could make one but I really don't think that should be necessary.

Any help is gratefully received,

Ray.

[Pete K.]

Since I haven't rebuilt my '25 Dodge transmission, it seems to shift OK, as only driveway miles are still being clocked. (Still have registry and title problems.) Try draining gearbox and pouring in straight STP. It's thick, very thick. I use it in my original '31 Model A pickup and drive it every nice day with no shifting problems. In New England here, we have hot summers and cold winters. The little Ford doesn't have a multiple plate clutch. I don't see why it would matter. To change out the pilot bearing on the Dodge transmission, either the engine or the rear end/torque tube has to come out to separate the transmission from engine as far as I can see.

[lozrocks]

I'll speak from my experiences with my 29s. From what I have read here I think you will need to pull it apart. The most common problem is adjustment and the next is a simple burr on the clutch plate or pressure plate. Even though you can turn the clutch plates with your hand doesn't necessarily mean that there still isn't a some small burr keeping contact between the plates. Heavier oil also may be making the problem worse not better.

I had a similar problem and located it by running a steel rule over the surface. I tied the clutch pedal to the floor and rotated the pressure plate by hand with the rule between the surfaces. I found a very small piece of the lining had bent over and was in contact with both surfaces. Easily moved by hand but enough to remain gripped with the pedal depressed.

[R.White]

Lozrocks, thankyou for responding. Opinions obviously differ and that is to be expected. It's all conjecture at this stage but I found your comment about the oil interesting because it seems to go contrary to popular belief. When I changed the oil it became apparent that a thinner gear oil had been used. It was something of a surprise to me that when I tried driving the car, the problem seemed worse; not better. Many people, including myself have always thought that the heavier the oil the more it would slow things down, so that with increased drag on the gears a quicker, quieter change could be effected. The downside to this is increased load on the engine. Our observations seem to concur and to be candid have me baffled.

The problem you had with a bit of lining material 'catching' would be a result. I shall try out your suggested remedy before tearing it all apart; just in case.... you never know! It's got to be something that only shows up in neutral.

I may be thinking about this too much and I will, in the end, have to bite the bullet and take it apart.

Cheers,

Ray.

[lozrocks]

The oil quandary??

I have seen on numerous occasions people stating that you must use 600 weight oil and anybody who tells you different doesn't know what they are talking about. I'm one of those people who doesn't know what he is talking about! (and I have been told)

I use 140 weight oil in my gearbox (1929 Chrysler) and it changes perfectly. My father’s DA uses 120 weight oil and my brothers DA also uses 140 weight oil. No noise, no grinding whatsoever. Years ago I found a British Army maintenance manual for a series 1 landrover with a crash gearbox. The British Army did not use the same oil in every vehicle, but had four grades to select from. In great detail it explained how to select the oil and the only way is by trial and error.

The starting point is to understand that the clutch plate (and obviously the input shaft of the gearbox) must continue to spin when disengaged from the engine. For vehicles with a crash gearbox the clutch must continue to spin for between 4 and 7 seconds. From memory 5 seconds was the optimum. If the gearbox spins for longer it makes it more difficult to select first gear when stationary. If the gearbox spins less it makes it more difficult to change between gears when on the move. Optimum time to change gears according to the British Army is 3 seconds (double de clutch operation).

If you are using 600 weight oil the oil sticks to the gears and makes them heavier and thus makes the gears spin longer. So a gearbox with 600 weight oil will stop spinning before a gearbox with 700 weight oil. Dodge and Chrysler specified these weight oils way back in 1929. These oils are heavy and sap power from the engine.

Today we have some very good gearbox oils that are a damn sight lighter, more readily available and cheaper. The disadvantage is that the modern oil will leak because it is designed to flow. And because it is lighter it also works in the opposite way to the heavier oils because a thin film of the oil is on the gears, with most of the oil in the pan. A gearbox with 140 weight oil stops spinning before a gearbox with 120 weight oil.

Laurie

[R.White]

I must say, Laurie, that is quite an education. Pitty then that I have just bought 20 litres of heavy oil !

Your persuasive argument, however, presupposes that the clutch and gearbox are in sound order. With my car, there must be something 'catching' and preventing the pressure plate from ever coming to rest in neutral. It stays still when a gear has been selected but on moving into neutral off it goes again!

I presume you avoid using EP (extreme pressure) gear oil which I have been led to believe has an adverse effect on brass bushes? I say this again with doubt in my mind as the synchro rings in more modern gearboxes are made from this very material - but then again I have always had to replace them because of wear which eventually breaks them up. It's all a bit confusing.

Obviously, if I can resolve the issue, I will keep the forum informed of my choice of oil.

Not a bad little thread, this. I wasn't really expecting quite such a contentious issue!!

Ray.

[R.White]

I don't usually get this lucky but it's sorted itself out!

Having pumped a little more grease into the throwout bearing (hopefully not too much) and left it for a day, I was just about to start taking off the exhaust in preparation to removing the transmission when I thought I would just give it one more run. To my great delight and surprise, the pressure plate came to a halt in neutral just as it should - regardless of revs - and gear change became easy.

Judging by the parlous state of the grease tube, I imagine that the throwout bearing must have been deprived of lubrication for a considerable time. When the new tube arrives I will replace the zerk which I fitted temporarily, and put the toe board back as before.

In the long run, I will remove the transmission for a rebuild and at the same time overhaul the pedal mountings which are rivetted to the engine support frame and have become loose. In the short term I need to replace some of the exhaust which had been poorly repaired in the distant past.

My thanks for all the help you guys have given me.

Ray.

[Pete K.]

Ray, I'm glad to hear things are working better.

[Jamie L Butler]

good outcome. I've noticed that when I turn the grease cup, I'm not getting any grease and have sometimes had a similar issue to you though intermittently, the zerk idea is a great idea, I think i'll do this and clean out the tube as I think the old grease has become blocked somewhere between the cup and bearing. 

I bought the car from an elderly gentleman 20 yrs ago and it was his first car, he bought from his mechanic in the mid 30's. He cut the back off in 1949 and burnt it at the tip and fitted the wooden tray and used it to cart stuff from his farm to the market. He told me specifically to use 250 oil in the differential and 140 in the gearbox, but with some 250 mixed in as well to make it smoother.

[Minibago]

On 5/11/2013 at 6:28 PM, lozrocks said:

The oil quandary??

I have seen on numerous occasions people stating that you must use 600 weight oil and anybody who tells you different doesn't know what they are talking about. I'm one of those people who doesn't know what he is talking about! (and I have been told)

I use 140 weight oil in my gearbox (1929 Chrysler) and it changes perfectly. My father’s DA uses 120 weight oil and my brothers DA also uses 140 weight oil. No noise, no grinding whatsoever. Years ago I found a British Army maintenance manual for a series 1 landrover with a crash gearbox. The British Army did not use the same oil in every vehicle, but had four grades to select from. In great detail it explained how to select the oil and the only way is by trial and error.

The starting point is to understand that the clutch plate (and obviously the input shaft of the gearbox) must continue to spin when disengaged from the engine. For vehicles with a crash gearbox the clutch must continue to spin for between 4 and 7 seconds. From memory 5 seconds was the optimum. If the gearbox spins for longer it makes it more difficult to select first gear when stationary. If the gearbox spins less it makes it more difficult to change between gears when on the move. Optimum time to change gears according to the British Army is 3 seconds (double de clutch operation).

If you are using 600 weight oil the oil sticks to the gears and makes them heavier and thus makes the gears spin longer. So a gearbox with 600 weight oil will stop spinning before a gearbox with 700 weight oil. Dodge and Chrysler specified these weight oils way back in 1929. These oils are heavy and sap power from the engine.

Today we have some very good gearbox oils that are a damn sight lighter, more readily available and cheaper. The disadvantage is that the modern oil will leak because it is designed to flow. And because it is lighter it also works in the opposite way to the heavier oils because a thin film of the oil is on the gears, with most of the oil in the pan. A gearbox with 140 weight oil stops spinning before a gearbox with 120 weight oil.

Laurie

I know this is an old post and the issue has been resolved and was not caused by the oil but I would like to clarify some points in this response regarding the recommendation of oil type / viscocity.

The cars listed as examples using much lighter oil are later cars with different gearbox design.

The gearbox design in the four cylinder Dodge Brothers cars fitted with multi plate clutches disconnects the lower gears / layshaft once top gear is selected.
Much is made in this post about the 1940’s 50’s 60’s Landrover and the Military recommendations, with respect, not applicable here.

The heavy oil recommended for the late teens early 1920’s Dodge Brothers cars is to assist in spinning the layshaft gear set to allow second to be selected, correct road speed and engine revs are most important.

The easiest way to effect a quiet gear change is to drive the car in each gear  and note the road speed and engine note. Changing down should be done at those road speeds with corresponding engine revs. Momentum is important so going up hill avoid waiting until you run out of puff, change down at the road speed you should be changing up. If your up change is noisy then you need to increase your speed before changing up.

Back to the oil, please take into account the vehicle in question.