Clutch stuck?

If the plate, disk and flywheel surfaces are free of any tranny oil or grease residue cooked onto the mating surfaces, then, even if they’re all dry, I would get some 100-grit sandpaper and lightly rough up the disk, flywheel and plate surfaces and put it all back together.

Of course, if you don’t trust that, you could always just shotgun it and install a new clutch plate and disk, too.

something that could be useful to refer to while staring at the rabbit hole from a safe distance something that needs to framed and hung on the wall of any workshop

I had a 1950 Chevy sedan that locked up while sitting for months. What I found is moisture from the ground had caused some rust to form and made the disc adhere to the flywheel and pressure plate. The starter wouldn't even budge it. I ended up rocking the car, but eventually put it in gear and got the family to push it backward out of the garage, while in gear, and popped the clutch to free it. I would drive it around the block and ride the clutch a bit to clean up the surfaces. Ended up putting carpet under the car and that seemed to help control the moisture. I also moved the car closer to the hot water heater in my garage and try to drive it once a month. This only happened in the winter months here in California.

Ed,  I'm going to say that you have this figured out, albeit you REALLY did do it the hard way.  If you are looking for sage advice and true wisdom, pls wait for @Stan Galat to chime in, as I can offer rather little of either.  @Gordon Nichols has already given his take,  although I think 100 grit is a little coarse.  I'd be inclined to use 600 emery. Aside from that, I think I'll go along with the minor corrosion theory of adhesion. That said, I really would consider the Nichols do-it-right proposal: buy new eqt (clutch and disk) and consider that you are back to 100%.

FWIW, I had something similar come up with my derelict pick up truck, which has been sitting outside for way too many years, and is now officially a "project" to recondition.  I'll leave that story of woe for another time, and only mention here that said truck had to be moved off the asphalt in order to have all of the black-top seal coated.  I could not budge the truck and its engine is non functioning, in case you were wondering.  It has disk brakes at front, drums at the rear.  The front pads were properly welded to the rotors via the above mentioned corrosion adhesion process. Stuck solid.  I had to remove the caliper assemblies and then remove the pads and reinstall the calipers without the pads in order to get the truck so I could push it.  Getting the caliper/pad assemblies off took a hammer. Of note: the corrosion adhesion process apparently does not have effect on drum brakes.  Or at least not yet.

Stupid preventative measure to thwart this problem: store the car with the clutch depressed, somehow. I would not really advise this approach in good faith, as such a thing likely would not be good for the clutch spring.

PS, the problem solving flow chart is brilliant.

@Gordon Nichols posted:

If the plate, disk and flywheel surfaces are free of any tranny oil or grease residue cooked onto the mating surfaces, then, even if they’re all dry, I would get some 100-grit sandpaper and lightly rough up the disk, flywheel and plate surfaces and put it all back together.

Of course, if you don’t trust that, you could always just shotgun it and install a new clutch plate and disk, too.

No, I'd veto that. The flywheel, PP, and crank are balanced together and indexed.

I'd also not use 100 grit, that's a bit course. Maybe a Scotchbrite pad on a drill, and finish with carb or break cleaner.

But yeah Ed, put it in gear with e-brake on, push the clutch in and start it. That woulda broke it loose.

If it was all balanced up as Danny says, then you might not want to replace just part of the business. And for an uninformed fellow such as myself, is that a common way to balance things: all of it lashed up together?  I can certainly see the flywheel and everything forward as one dynamic unit, and then maybe taking the PP separately.

All I've got is this (for @550 Phil): This is Exhibit 23 why a (somewhat) climate controlled garage is a baseline necessity for a hobby car.

@El Frazoo posted:

If it was all balanced up as Danny says, then you might not want to replace just part of the business. And for an uninformed fellow such as myself, is that a common way to balance things: all of it lashed up together?  I can certainly see the flywheel and everything forward as one dynamic unit, and then maybe taking the PP separately.

I just had a rotating assembly balanced.  First they spin up the crank and balance. Then you add the flywheel, and balance. Last the pressure plate goes on, gets indexed, then balanced.

How would you balance a pressure plate by itself?  It would need to be bolted to a fixture of some sort.

Thanks, all. I appreciate your insights. I think I'll just clean it up and bolt it back in.

@DannyP this is the Suby, not the Spyder. The engine came out of another car and got transplanted stock into Bridget, with the KEP adaptor and flywheel affixed as directed with no additional balancing or indexing. I was given to understand that the flywheel was itself made neutral in terms of potential wobble. It does seem to work.

@Stan Galat touche´. I was going to address your experience with cold storage-ing your IM by contrasting your North Dakota-like winters (i.e. midnight temps suitable for high-level physics experiments in superconductivity) with the comparably mild experience I've enjoyed in my unheated garage lo these past 15 years. It very seldom gets very close to freezing in there. Never a problem...BUT. Yeah... there's moistness in that back bay after a heavy rain. I do occasionally need to sweep water out. Gonna have to fix that.

I'll grant the winter in question was dark and deep, but people all over this nation contend with obstacles that a garage solves. An attached and conditioned "car hole" (as my daughter calls them) is perhaps the greatest innovation of the 20th century. I'm not sure what I'd miss more, not having a car or not having a garage, but both are equally incomprehensible.

Machinery just lasts longer in a covered, dry, and reasonably temperature constant space.

"Machinery just lasts longer in a covered, dry, and reasonably temperature constant space."

Yeah, what he said.

Machinery, animals, people... yep.

@LI-Rick posted:

I just had a rotating assembly balanced.  First they spin up the crank and balance. Then you add the flywheel, and balance. Last the pressure plate goes on, gets indexed, then balanced.

How would you balance a pressure plate by itself?  It would need to be bolted to a fixture of some sort.

How does one balance a tire and wheel?

@edsnova posted:

How does one balance a tire and wheel?

Most wheels have a concentric hole in the center, makes it easy.  If not, you have to bolt it to an adapter of some sort.  What’s your point?  Have you ever seen a crank balancing machine?

I misread "pressure plate" as "flywheel," Rick. But, no. I've never been in a room with a crank balancing machine, or if I was, I did not recognize it as such. That's how much I know about all this. It's why I asked the question up top.

Not looking for an argument.

@Stan Galat Just to add that (at least in NJ) controlled temperature is a spectrum, and altho most is best, some is better than none. In particular, a car port or screened garage may in a way be worse than no protection. During the summer I had 16x8 screens but not a well-sealed door, any ferrous surface in the garage, including hobby car engine parts and tools, would cool overnight and then condense the humidity out of the daytime air. The rust was just surface rust, but amazingly fast and widespread. Since then, with a well-sealing rollup door, insulated walls, and a full ceiling, even an unheated, uncooled 20x30 space takes days to catch up with ambient temperature variations and condensation is no longer an issue.

@edsnova posted:

I misread "pressure plate" as "flywheel," Rick. But, no. I've never been in a room with a crank balancing machine, or if I was, I did not recognize it as such. That's how much I know about all this. It's why I asked the question up top.

Not looking for an argument.

Sorry Ed, my answer was a little snarky.

Here is a video of Jose @ DPR balancing a complete rotating assembly.  The guy I wound up using had a very similar strobe type balancer.  I originally brought my parts to Lawrence Racing Engines. He has a much newer, computerized balancing machine, but unfortunately a type 1 crank is too small to fit on his machine.

https://www.youtube.com/watch?v=kn7Bvjdqm8E

@wrkinprogress posted:

@Stan Galat Just to add that (at least in NJ) controlled temperature is a spectrum, and altho most is best, some is better than none.

I agree 100% with your entire post, but this line in particular. That's why I keep saying things like "Machinery just lasts longer in a covered, dry, and reasonably temperature constant space."

It doesn't have to be 70 deg all year long, just enough to stay above freezing and to slow down the kind of condensation-inducing events that happen in an open but covered space. The absolute worst is a covered, wet carport on white rock. You're far better just parking on the street.

@edsnova posted:

Machinery, animals, people... yep.

Exactly.

Great video @LI-Rick!

@LI-Rick posted:

I just had a rotating assembly balanced.  First they spin up the crank and balance. Then you add the flywheel, and balance. Last the pressure plate goes on, gets indexed, then balanced.

How would you balance a pressure plate by itself?  It would need to be bolted to a fixture of some sort.

So, I've given this some thought, because it's not like a pressure plate lasts as long as an engine - you're going to need a new pressure plate before you need a new bottom end.

I'm just a gorilla with tools, but it would seem the choices would be two:

1. You could buy two or three extra pressure plates and have them indexed and balanced with the engine. Nobody does this.
2. You could build a fixture with a straight shaft with a crank end welded to it to accept a flywheel. You could affix the flywheel to the shaft in the usual manner then balance it to within a few grams. Then, you'd have the ability to balance one or 100 pressure plates independent of the rest of the rotating assembly.

Unless you're using an imbalance in the pressure plate to act as a counterweight for some other problem with the balance, I don't see why it wouldn't work.

The way we do it now is silly. A pressure-plate is a wear item. There has to be a way to balance them without tearing down the entire bottom end of an engine.

@Stan Galat posted:

So, I've given this some thought, because it's not like a pressure plate lasts as long as an engine - you're going to need a new pressure plate before you need a new bottom end.

I'm just a gorilla with tools, but it would seem the choices would be two:

1. You could buy two or three extra pressure plates and have them indexed and balanced with the engine. Nobody does this.
2. You could build a fixture with a straight shaft with a crank end welded to it to accept a flywheel. You could affix the flywheel to the shaft in the usual manner then balance it to within a few grams. Then, you'd have the ability to balance one or 100 pressure plates independent of the rest of the rotating assembly.

Unless you're using an imbalance in the pressure plate to act as a counterweight for some other problem with the balance, I don't see why it wouldn't work.

The way we do it now is silly. A pressure-plate is a wear item. There has to be a way to balance them without tearing down the entire bottom end of an engine.

Stan, I think you are exactly correct.  Jake Raby used to recommend getting 2 pressure plates balanced, which is probably not a bad idea.

For a shop that is doing the same type of work all the time, having a crank and flywheel jig just seems to make a lot of sense, but there is one issue.  Pressure plates do not fit tightly inside the flywheel register.  What most guys do is peen them on the outside nubs to tighten up the fit. Some go as far as drilling for a couple of small dowel or roll pins to keep the location exact.  If all one does is bolt the pressure plate on, I don't care how balanced it is, you will not get repeatable results and out the window your balance job goes.

How important is balancing the pressure plate?  Well, on my combo, the flywheel was 5g out, the flywheel 2g.  The pressure plate was 20g!  

@edsnova Understood it's the MG, IDK why I thought it was the Raby in the Spyder.

As to @LI-Rick comments, a couple grams of unbalance makes a HUGE difference when spinning at 6000-7000 rpm.

Theoretically if all components are balanced individually all should be perfect. However, a dynamic balance of all bolted together will usually reveal room for improvement, which is why they should be done together.

... and there it is: "room for improvement."  at what point is better the enemy of good?  In this case, I dunno. I'd imagine with my limited experience that there would be degrees of balance. Theoretically, if each individual moving part was balanced (pistons, rods, wrist pins, etc each weighed out to a fraction),  the crank balanced, the flywheel balanced and the clutch balanced, when you bolt them all up concentrically then all is good, right?  If you took all those individually balanced parts and lashed them up and then dynamically balanced the set, that would be better, right?  How good is good enough?  I'd say the lighter the engine and the higher it revs , the more it will matter.

My first 356 (1600 Normal) had to be rebuilt and I asked for a complete and precise balancing of all parts.  I have no idea what the shop did, exactly, but I do know that that engine ran extremely smooth. If you sat in the car and adjusted the rear view mirror so you could focus on something at a fair distance from the car, then just slowly rev the engine, if there would be any imbalance, then that image would vibrate a little (or a lot) and tend to blur out at various resonant speeds.  The engine in question revealed no such blurring all the way up.  Note: all the way up was supposed to be a modest 4500, and it would and did run to 5,000.  Smooth all the way. Suping up one of these Type 1s and running it to 7,000 is, I'll agree, a whole other discussion.

@Stan Galat posted:

I agree 100% with your entire post, but this line in particular. That's why I keep saying things like "Machinery just lasts longer in a covered, dry, and reasonably temperature constant space."

It doesn't have to be 70 deg all year long, just enough to stay above freezing and to slow down the kind of condensation-inducing events that happen in an open but covered space. The absolute worst is a covered, wet carport on white rock. You're far better just parking on the street.

Here in the PNW I made sure the door was well sealed and then installled an adequately sized desicant style dehumidifier with the drain hose run through the wall to an outside drain. I found there's little negative effect on the electric bill running it on the "drier-than-Death-Valley" setting, so that's where it sits 24/7. No rust on tools, etc. for only a few hundred dollars.  It doesn't get cold enough here for long enough to bother with heat, but that's not completely off the table in the future. Surprisingly, summers here are so dry my chapstick consumption doubles between June and October, so no need for AC.

@El Frazoo asked a question regarding balancing rotating parts that had been bugging me, too, and that is:

”How good is good enough?  I'd say the lighter the engine and the higher it revs , the more it will matter.”

I totally agree with that.  I have replaced maybe 40 or 50 clutches, mostly on GMC school buses, but also a Ford Bronco and Mustang, a Toyota Corona MKII and an odd assortment of dune buggies, hot rods and various others.  Most of those had the engine still in the vehicle and all of the new pressure plates had partial drill dimples indicating that some balancing had taken place at point of manufacture.  All of them went together without further balancing and seemed to run just fine.  In fact, I have never had my engine’s rotating mass balanced other than when I bought a long block and paid to get it balanced as part of the assembly.

Having said that, all of those applications were in relatively heavy, low-reving engines that might see 4K rpm once in a great while.  The Mustang was the exception, but that was red lined around 5,500 and often saw that (I was younger, then).

Back when people actually drove manual transmissions they wore out a lot of clutches.  All of them were removed and a new one installed and that was that, no balancing involved, but again, most of those weren’t in high revving applications.

So I guess if you are having a custom high-revving engine built and the builder can get it done, then get the engine’s rotating bits balanced and mechanically scribe the flywheel and a crank dowel pin to locate everything later on to keep things in balance (more or less) - Marking a dowel pin with a “Sharpie” isn’t good enough.  Then, if/when you need to replace the pressure plate (As I did last Spring), just go get a new one of your choice, check to see if it has balancing dimples somewhere on the mounting plate and install it, centering it in the flywheel depression as best you can.  That’s about the best you’re gonna get.

@Gordon Nichols, out of all those clutches you replaced, how many were just the driven disc and you put the old pressure plate back in?  Back when I was a young guy with no money, this was SOP.

@LI-Rick
That’s true, and I did that on a lot of them like that, but I never marked the plate to insure that it went in precisely as it came out, either.  Just grabbed the plate and put it in, assuming that it was balanced (They always seemed to have drill dimples so I assumed they had been balanced).  But remember, it was rare for most of those to see even 3K RPM!

Based on engineering contacts I had at Ford when I worked at Computervision (they used our software as their first CAD tools) they balanced everything individually and then just put them together (They balanced things as spinning assemblies on higher end engines, but not the passenger or middle-grade engines).

My point is still valid:   If you or your engine builder have the resources to balance spinning assemblies to a gnat’s a$$, then do it.  You will probably be rewarded, as Kelly mentioned above, with a smoother-running engine, especially if you plan on consistently revving it beyond 4K a lot.

BUT, if you can’t justify the additional cost or don’t think it necessary because you’re building a “general purpose” or mostly stock engine that won’t be high-revving much, OR you’re just replacing an old, tired pressure plate and don’t want to pull your engine apart for cost reasons, then it’s probably fine to install it right out of the box.  Many others have done just that.

@Gordon Nichols, oh, I absolutely agree with you.  I don’t think anyone is tearing down a well running engine to balance a pressure plate.  Why the manufacturer’s don’t at least get them within a few grams seems like cost cutting to me.

Btw, VW type 1 engines are internally balanced, where as some engines are externally balanced.  That is why Ford small blocks must have the correct harmonic balancer for the year, as they have different weighs.

Copy that.  Slap 'em out, slap 'em in.  I have always noticed balancing holes on replacement pressure plates.  Also, I have done just a friction disk replacement and kept the old pressure plate.  Never noticed or thought about maintaining any index when reassembling.   That said I came to understand at one point that keeping a pressure plate the looked just fine was a mistake, since one cannot tell the strength of finger (diaphragm) springs or coil springs just by looking at them.  Learned that one the hard way. Aside from that first 356 Normal motor, I have never come up against an opportunity to "do it right" vs do it economically. In that case I chose to do it right.  My Speedster mill (a 2332) was sold to me as thoroughly "blueprinted", which I took to mean everything balanced to a nonce.  FWIW, it does seem to run smoothly, and maybe has touched 6 grand a few times.  I think JPS said that such a rev would be fine, but more "might break it".

As for @DannyP and his screamin'  FVee 1200 cc "stroker", he wants and gets every little bit all the way to 7,000 RPM, I suppose, so doing every little thing while balancing that motor is where it's at.  Recall that horsepower is torque times RPM, so lots of RPM can mean lots of HP.  It's why F1 hypercars are built to turn upwards of 15,000 to 17,000, and can get 1,000HP out of 2.2 liters.

@El Frazoo posted:

As for @DannyP and his screamin'  FVee 1200 cc "stroker", he wants and gets every little bit all the way to 7,000 RPM, I suppose, so doing every little thing while balancing that motor is where it's at.  Recall that horsepower is torque times RPM, so lots of RPM can mean lots of HP.  It's why F1 hypercars are built to turn upwards of 15,000 to 17,000, and can get 1,000HP out of 2.2 liters.

You can't rev that high with a Vee. After about 6700 rpm the valves start floating. They are mandated to be single springs. I do plan to build heads with beehive springs, which should go up there. Any single steel spring is legal.

And a 1200cc Vee is the opposite of a "stroker", at 64mm and on a non-counterweighted crank. But I think you knew that.

Honestly, my type1 2165cc would rev higher that the 6700 rpm I have it limited to. It certainly breathes better and has more cam than the stock Vee.

@El Frazoo posted:

  I'd say the lighter the engine and the higher it revs , the more it will matter.

F=MA, or Force equals Mass times Acceleration. So I don't agree, less mass=less force.

It ALWAYS matters as to balance, yes, and more so the higher they rev. So, true.

So maybe change the lighter engine to HEAVIER. More mass certainly means more force.

@DannyP But, the heavier the reciprocating parts of the engine, the smaller the percentage effect of any given imbalance of weight. So the lighter the engine, the better job of balancing needed. Assuming I haven't lost the handle of the discussion.

@wrkinprogress, precisely. Heavier here mostly means  the structure that holds all the parts together, which is to say the case/block.  heavier, bulkier means much stiffer, more able to deal with those forces Danny mentions, the imbalance loads. .  The reciprocating parts matter of course, and they get weighed out to be the same, pretty simple, although must be done with care.  The rotating parts are what matter the most, the crank and flywheel being the major contributors.  Here dynamic balance to damp resonances is key.  And yes of course the clutch assembly is part of that equation.  If each of these items is balanced separately, then lashed up, that should be pretty good, but does not allow for alignment  imperfections in said lash up.  The best you could do would be to dynamically balance all three together, and get it smooth as can be.  So its kinda:  good, better , best.

As for FVee, i continue to get educated on what exactly that formula requires.  Fun stuff.

@wrkinprogress posted:

@DannyP But, the heavier the reciprocating parts of the engine, the smaller the percentage effect of any given imbalance of weight. So the lighter the engine, the better job of balancing needed. Assuming I haven't lost the handle of the discussion.

I kind of agree with you here. Except F=MA.

In my mind, lighter components generate less forces. So a smaller imbalance(race balance rather than a standard spec) generates less imbalance than a larger one, no matter the mass of said components. Lighter(and hopefully balanced) components that are spinning generate less vibration and destruction. Plus they accelerate and decelerate quicker.

On Wheeler Dealers Season 18 Episode 2 they talk about this very thing. The mechanic that has been on the series lately is Marc "Elvis" Priestly. Priestley was an F1 mechanic and worked for McLaren for 10 years. In this episode they buy a Peugeot T16 Rally car. The French made a Euro Spec version for themselves that was 105hp but the model sold in the UK was only 75hp. The Euro Spec car sells for nearly $250K while the lesser cars sell for next to nothing. They buy a UK version with the intention of raising the HP to a more acceptable level. By adding lighter pistons, balancing the crankshaft, and changing the single barrel carb to a throttle body from an 1100 GSXR (IIRC). They put it on a dyno, not shown, and took it from 74bhp to 130bhp.

https://youtu.be/wfMgKO5-agE?s...M6DJe5VSd9&t=346

Yes the devil is in the details.

You guys are the best. So I cleaned up my pressure plate and flywheel with a wire brush, shot them with brake fluid, dried with a clean rag and put them back together. There are no indexing marks on either piece so I lined up the lightening holes on the theory that, if they were balanced together like in Rick's video they would likely have got drilled in the same general area.

I'll put the engine back in next weekend, probably, and fire it up asap after that in hopes of success.

Ed, just a quick question: is the clutch a diaphragm type -- most are.  You might very carefully examine the outer roots of the fingers in that spring plate.  If there is any deterioration of the clutch it will show up as microcracks at the root of the spring fingers.  The fingers end in little circular holes as I recall.  Over extending the clutch  (too much travel of the TO bearing due to poor cable adjustment) can cause excessive stress at this location which is a stress concentration area.  also just plain metal fatigue will occur with age.  (how old (miles??) is that clutch? Said microcracks would be very hard to see and easily missed if you're not looking. The official way to determine is to use dye penetrant, which would allow the cracks, if any, to be visible.  Diaphragm springs are very cool as they exert a lot of force for rather little weight, and are very symmetric, so easily (or naturally) balanced when rotating.  They do have this failure mode, however.  And I'll suppose you do not need to ask how I know this.