Super Seven S2 Clutch Issues

[TEM]

That Dave Bean catalog is great information.  I wonder if they still have them?  I'll ask Ken next time I talk with him, which will probably be tomorrow based on past frequency.

[TEM]

All oil (Engine, Trans, Diff) is new.  Oil came out like you would expect after sitting for 50 years - black and thick.  For the gearbox I used Millers Classic 80W90 GL4.  It didn't seem to make a difference.

 

I have tried two clutch MC's (5/8" & 3/4") so unless both have the same internal failure I doubt that's it.  Also the 3/4" is off my brakes and they are fantastic - short throw and nice an firm, no sponginess.  And the slave is just a hunk of metal with 3 holes.  It doesn't leak so nowhere else for the oil to go.

 

Yes, only happening when running.  When not running, the first gear selected requires a little effort to align the gears but after that all the gears can be selected but I wouldn't call it smooth.

 

The Gearbox looks like the one in the picture on pg E14 of the manual for the 109E.

 

I'll put the slave hose back on and re-bleed so I'll be able to look into the clutch housing again.  The borescope in this space was useless but I'll try to get some meaningful pictures of the throw out bearing.  I can't see the pressure plate.

 

I will be able to do more measurements on the slave cylinder when my better half returns next week.  Until then I'm relegated to one-person tasks.

 

I think I have run out of other things to try.  I probably need to pull the engine and see what's going on with the clutch.  Is there a trick to getting the manifold bolts out without snapping them off or stripping the heads?  Will running the engine a little fist help?

[SENC]

50 minutes ago, TEM said:

That Dave Bean catalog is great information.  I wonder if they still have them?  I'll ask Ken next time I talk with him, which will probably be tomorrow based on past frequency.

If not, let me know.  I seem to recall having a second copy at some point and happy to look around to see if I can find it.  It is a great resource.

[SENC]

1 hour ago, TEM said:

Is there a trick to getting the manifold bolts out without snapping them off or stripping the heads?  Will running the engine a little fist help?

I just took mine back off to deal with an exhaust leak at the head.  I use a long allen key with the short side cut down to about a 1/2".  Carbs off first.  Loosen the 2 middle bolts, then 2 on the outside of the intake manifolds.  You may have to work back and forth.  You'll get to the point that you can angle each intake manifold out (way from each other).  This will be the reverse of the way you'll put them back.

 

I'm planning to try going back with studs and jet nuts- will let you know if successful.

[TEM]

Let me know if it works.  These Allen head bolts scare the crap out me.

[fotsyr]

You are using a dash 4 clutch hose? Brake line is dash 3.

[TEM]

Sorry,  What's a -3 and -4?  Are these part numbers?

There needs to be a hose in there somewhere given the body and transmission can move independent of each other.

[MV8]

AN size as in AN-3 or AN-4. Either works fine.

Get a full engage before cracking the allens loose, even if you can only turn the wrench a little. Then switch to a wobble to spin it out.

 

It looks like socket head screws are the only thing that would fit that intake. 12 point nuts on studs would be bigger in od.

Edited June 12 by MV8

[fotsyr]

ID, AN dash 3 = 3/16 ID, AN dash 4= 1/4. I beg to differ but clutch lines should be dash 4, displaces more fluid. 

[MV8]

The master determines how much fluid is displaced. The line size determines how fast. This is one stroke, not a running pump where you can get more strokes in a period of time (that is how they are rated) with a bigger hose to run faster at the same pressure. One stroke is one stroke.

[SENC]

On 6/12/2024 at 1:16 AM, TEM said:

Let me know if it works.  These Allen head bolts scare the crap out me.

Dry fit today and pretty confident it will work, as long as the studs used are less than 1.5" long.  AN jet nuts only require a 3/8 socket or wrench and it appears I can just fit those in.

 

I'm waiting on gaskets - will likely be late next week before I get back to it and can officially confirm, but feeling good about it after testing.

[TEM]

Sounds good. I'll be waiting for your reply with interest.

[TEM]

Was able to setup a camera to view the slave cylinder while driving.  In all cases the slave extended full stroke when depressing the clutch pedal.  Stroke of the slave is close to theoretical at approximately 0.87" of travel vs .095" theoretical.  I say approximately 0.87" because at full theoretical stroke the slave piston peeks out of the bore by 0.162" and when driving I can see the piston sticking out but only about half of the 0.162".  Gear selection issues persisted throughout the drive.

 

Unless anyone can suggest other things to look at, I think I have to pull the engine and transmission to see what's going on in the bell housing.

[MV8]

You didn't actually provide what I was asking for on June 11th, but your post seems to confirm the release bearing is too short/wrong type for the pressure plate resulting in the slave end of the fork being too far aft before any pressure is applied.

[SENC]

12 hours ago, MV8 said:

You didn't actually provide what I was asking for on June 11th, but your post seems to confirm the release bearing is too short/wrong type for the pressure plate resulting in the slave end of the fork being too far aft before any pressure is applied.

Though I follow your logic, I think this is may not be the issue.  There is enough "swing room" for the clutch fork that it could easily take up that difference, and once the slave rod is adjusted to the fork it should have essentially the same lift at the release bearing.  I suspect the adaptor and matching the release bearing to clutch type has as much to do with preventing premature failure of the bearing and/or damage to the bearing or fingers.  As he's not hearing bearing or other noise in the bellhousing, I suspect that isn't the issue.

 

The more I think about the primary symptoms of difficulty getting gears, the more I wonder about baulk ring wear and/or weak blocker springs - which combine to "brake" the shaft speed to match engine speed for smooth gear changes - or gear selector wear.  Both brass items designed to wear before damaging gears.  I think it was worth trying to eliminate clutch hydraulics to try to resolve before pulling the engine and gearbox - but the symptoms described seem to me to more likely point to gearbox rather than clutch.

 

TEM - the good news is that pulling these from the Seven is a good deal easier than doing so from the Elan - but as with the Elan be sure to empty the gearbox of oil or you'll have a heckuva mess!

 

[MV8]

It doesn't sound like you do. I'm not talking about worn bearings or PP fingers. Earlier, he said it was hitting. He also said the piston is protruding from the slave, so a falling fork ratio and not essentially the same as slave travel. Is the fork a 1:1 ratio?

Room to swing but from what point? We don't know the push rod length either.

 

 

 

[TEM]

Thanks Henry,

 

When I had the camera in place I noticed that when I had trouble getting into gear from a stop, the car would creep very slowly when the clutch was fully depressed and pushing on the shifter (A little hard than normal shifting).  It would stop creeping when I removed pressure from the stick and creep when pressed again.  This occurred in 1st and 2nd (only two I tried).  No creeping when the car was finally in gear when cold.  But after a short drive the clutch is definitely not disengaging.  If I apply the brakes with the car moving, gear selected, and clutch depressed all the way, the car tries to push past the brakes.  I tested this a number of times in both 1st and 2nd gears.  Therefore, I think that I'm looking at something in the clutch area as the main culprit.  Possibly a cracked release arm or damaged pressure plate.

 

I plan to dump both engine and gear box oil as the remote oil cooler hoses have to come off and I want to clean and inspect the sump.  And I expected the trans oil would spill out the back as soon as the engine is tilted. 

I was able to break loose the back three header bolts last night without drama.  I'll pull the nose cone today and, fingers crossed, loosen the others.  I need to pick up a load lever for my hoist then I'll dig in.  One question though, does the remote shifter need to come off first?

 

Any other recommended maintenance once the lump is out?

Replace clutch components (pressure plate, disc, throw out bearing, possibly flywheel and fork)

Replace drive shaft U-joints

Replace transmission mount

[TEM]

Pushrod length is 3" from the end of the slave body to the release arm.  This is steady state with slave piston fully retracted.

[SENC]

2 hours ago, MV8 said:

It doesn't sound like you do. I'm not talking about worn bearings or PP fingers. Earlier, he said it was hitting. He also said the piston is protruding from the slave, so a falling fork ratio and not essentially the same as slave travel. Is the fork a 1:1 ratio?

Room to swing but from what point? We don't know the push rod length either.

 

 

 

Not exact, but as I recall the fork/arm fulcrum is near the center of the fork so probably not far from 1:1.  I'll have to see if I have a cross-section diagram somewhere.  What's driving my suspicion is that he's getting clutch disengagement (at least when cold) so he's got enough travel occurring unless something is shifting.  I'm just not sure lack of an adaptor or incorrect bearing is going to be variable or cause shifting.  I could certainly be wrong, and it could be that he's right at the limit of tolerances - but after going back through pictures during my disassembly and rebuild I'm confident I don't have an adaptor though the DBE catalogue suggests I should, and I'm not having any issue with clutch disengagement.

 

2 hours ago, TEM said:

Thanks Henry,

 

When I had the camera in place I noticed that when I had trouble getting into gear from a stop, the car would creep very slowly when the clutch was fully depressed and pushing on the shifter (A little hard than normal shifting).  It would stop creeping when I removed pressure from the stick and creep when pressed again.  This occurred in 1st and 2nd (only two I tried).  No creeping when the car was finally in gear when cold.  But after a short drive the clutch is definitely not disengaging.  If I apply the brakes with the car moving, gear selected, and clutch depressed all the way, the car tries to push past the brakes.  I tested this a number of times in both 1st and 2nd gears.  Therefore, I think that I'm looking at something in the clutch area as the main culprit.  Possibly a cracked release arm or damaged pressure plate.

 

I plan to dump both engine and gear box oil as the remote oil cooler hoses have to come off and I want to clean and inspect the sump.  And I expected the trans oil would spill out the back as soon as the engine is tilted. 

I was able to break loose the back three header bolts last night without drama.  I'll pull the nose cone today and, fingers crossed, loosen the others.  I need to pick up a load lever for my hoist then I'll dig in.  One question though, does the remote shifter need to come off first?

 

Any other recommended maintenance once the lump is out?

Replace clutch components (pressure plate, disc, throw out bearing, possibly flywheel and fork)

Replace drive shaft U-joints

Replace transmission mount

Fractured or weak fork/arm could be possible, though I'd think that would get progressively worse and not recover when cold.  Weak pressure plate springs I guess could get worse with heat- perhaps?  Or possibly a point of wear at the fingers/platen/bearing that finds it's place when running?

 

I'd also wonder about the spigot bearing and the possibility it has fully or partially frozen or become damaged and transmitting rotation from engine to input shaft.  Not sure why that would only reveal when leaning on the shifter though - unless internal wear/end float is allowing forward pressure, too.  Will be interesting to see what you find when you pull it.

 

Yes, you need to remove the remote.  I'll attach a removal sequence I made when I removed mine for the first time.

 

Definitely check the spigot bearing as well as the tailshaft extension bearing and seal - these are common wear/failure items.  I'd also at least open up the top of the gearbox for inspection of gear selectors and bulk rings (I think you can estimate baulk ring wear based on where they sit relative to synchronizers or gears, but I'll have to go back through my notes on that).SevenEngineOut.docx

[TEM]

Thanks Henry, very helpful.

Is removing the radiator, starter, and generator necessary or just for convenience?