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 Posted: 08-03-2006 08:56 pm
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Rick Willard
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Hi folks,

I quickly searched the board for this topic, and didn't see it.  Hope that I'm not duplicating any previous post.  Here's my issue, and I'm open to all suggestions.

I have a bunch of new mechanical goodies on my car after a full engine rebuild and several other new parts.  Included in the list is a new clutch (pressure plate, disc, and throwout & pilot bearings).  I'm just under the 1,500 mile mark since the rebuild, and was enjoying a nice romp through some windy roads yesterday, when on the way home...a dreaded snag with the clutch. 

I had just done a pretty good 50 miles - nothing too hard on the car, but some windy roads for sure.  I was pulling up to an intersection a few miles from home, and I slowly started putting the car into first.  The clutch felt fine when I pushed on it, however...the car won't go into gear (in fact, it won't go into any of the gears).  I step back on the clutch, give the engine a tiny rev, and I can hear a slight squealing coming out of the bell housing.  I roll the car to the side of the road and turn it off.  I put it into first, step on the clutch, and turn the starter.  The car lurches forward because it's being "pushed" by the starter as if I'm not pushing the clutch at all.  Then the engine turns over, and I drive the few miles home. 

During that trip home, the clutch resumes normal operation for the most part - a little sticky a couple of times, but...nothing ugly like back at that intersection.  However, if I stand on the clutch in neutral, and rev the engine a bit, I sometimes (not all the time) can still hear that squealing.  But again, the clutch feels just fine on the pedal, like everything is OK.

I'm thinking that we've got an issue with the throwout bearing.  Before I just start taking the transmission down, I thought I would double-check to make sure that the clutch fork is solid on its pivot, and that its in line and egaging the throwout correctly - at least what I can see from the ground.  Does anyone have any suggestions for these symptoms?  I've certainly wrestled a JH tranny down a time or two before, but it's not exactly the thing I was hoping to do anytime soon. 

If anyone has any ideas or experience with this...I'll take any/all suggestions.

Many thanks,

Rick Willard

 

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 Posted: 08-03-2006 11:14 pm
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Greg Fletcher
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Did you try to readjust the cable? How old is your clutch cable? I'd have a look over if this is the original one. I've had a few go bad over the years and the wire winding inside (or at either end) can stretch and fray before breaking. Also check that the end is mounted properly in the hole on the bell housing. Occasionally on the JH, the ends pop out of position and creates what appears to be a grapping problem at the clutch.

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 Posted: 08-09-2006 12:48 am
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Rick Willard
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Thanks for the reply, Greg!  Here's an update for you and anyone else on the board who might have some ideas....

The tranny is down; the clutch plate and disc are fine, but it appears that the pilot bearing failed.  There was nothing but a shell left up where there used to be a brand new pilot bearing.  Also, the throwout bearing is not quite up to snuff – possibly damaged by the vibration being caused after the pilot bearing failed.  Again, this happened within 1,500 miles of new…everything with the engine.  

One initial theory is that the pilot bearing might have been installed backwards.  If that was the case, the grease in the bearing just came right out, the bearing dried up, burned up, and the rest is history.  I don’t know this to be true for sure, because I’ve done two JH clutches personally on my past JH’s, and never had a problem with them.  The mechanic is scratching his head, saying he’s never seen anything like it, wondering if it was a faulty part.  However, after some of the expensive crap I’ve dealt with the last 12 months…I’m just trying to be wary of anything and everything, wondering if there are any other insights out there.

Do any of you have any of you have any experience with this?  If so, would you agree that the backwards pilot bearing is possible?  Any other theories out there?

By the way, I’m certainly not proud to be putting my stupidity (and poor experience) on display here.  But if it benefits anyone else in the Jensen World…all the better. 

As always, many thanks for your input/support.

Rick Willard

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 Posted: 08-09-2006 03:31 am
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Greg Fletcher
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Too bad about that, Rick, that's really blows. The pilot bearing cannot be installed backwards as the input shaft would never go in, unless it was smashed in somehow. I've never heard of failure with this low mileage myself, but everyone knows that this particular needle bearing, by design, is less than robust. If some of those small, little rollers fell out before installation was complete, I guess it could fail much sooner. I've always used the stock pilot bearing myself all these years, but installing a bronze bush in it's place, (an Oil Lite bushing) would be a safer alternative.

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 Posted: 08-09-2006 05:00 pm
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Rick Willard
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Good info.  I can live with that happening.  Had it been installed wrong, I'd be a little more ready to place some blame.  If it's likely some bad luck...I guess that's a little more acceptable.  Thanks a lot, Greg!

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 Posted: 08-15-2006 02:02 pm
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Rick Willard
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An update for those of you that provided me your input, and anyone else curious...the clutch is done and fixed.  As I mentioned before, the problem was the pilot bearing.  Some of you might know that I had the infamous "dead guy's engine" in my car initially.  That engine was installed with new clutch parts including the pilot bearing.  Well, after we determined that engine was not ready for prime time, and it was removed, the machine shop that built the new engine with the 2.2 crank moved the pilot bearing from the crank in the dead guy's engine to the new one.  That was likely where the mistake was made.

Luckily, those of us in Southern California have access to Viking Motorsports.  Because I've had such a difficult rebuild the past several months created by problems caused by poor machine shop work; and because they MIGHT have (perhaps should have) caught this before the tranny was mated back to the new engine...I think they felt pretty sorry for me.  They actually backed the work, and discarded any invoice they had brewing.  I didn't even have to ask them.

Can't say it enough.  For those of you anywhere near Southern California looking for a good place to take your Jensen...Viking Motorsports is definitely a solid option.

Cheers,

Rick Willard

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 Posted: 08-01-2007 06:00 pm
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jcdean
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A little thread resurection here.

I have just unstuck my clutch/flywheel in my 74 with the help of a tow strap and an a pull with my sons truck.  This is the second JH I have had now where the depression of the clutch will not disengage the transmission.  Both instances have been corrected with me sitting in the drivers seat with the clutch depressed and in fourth gear while I was pulled a few feet forward.  It jar's loose and it is if nothing had ever happened.  The first instance was in 1988 and that car never experienced that particular problem again.  I have checked everything I can think of (without dropping either trans).  So, have I been struck by lightening twice?  Any ideas what it could be?

Joey

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 Posted: 08-02-2007 04:48 pm
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Greg Fletcher
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Interesting, Joey. I've never seen a clutch stick like that, but I'm guessing that you don't drive your car everyday? Perhaps corrosion, moisture and dust has built up to create that situation.

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 Posted: 08-02-2007 05:36 pm
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jcdean
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Greg,

This is indeed the case.  I decided that my summer would be much more exciting with a few blood clots scattered throughout my lungs during the peak spring driving season.  That was followed by a record (for Oklahoma City) of 20 continuous days of rain and high chances for a couple of weeks after that (I try not to drive in the rain).  I'm guessing there was about 14 weeks of sitting with the battery tender as the only excitement it had.  With the humidity I am sure the flywheel was looking rather brown, but I still can't figure out how that would affect the clutch pucks.  I just love British cars.

Joey

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 Posted: 08-06-2007 11:52 am
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smcmanus
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A stuck clutch is not unique to British cars.  If a car sits long enough in conditions condusive to clutch sticking, the clutch will stick.  How much it sticks is determined by the sticking factors multiplied by the time the car sits measured in fractions of a decade. 

or simply said: Cs = sF X T

See link "multi problems" on this same forum.

Have a nice day

Steve

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 Posted: 08-21-2007 06:47 pm
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pbahr
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Steve,

Where can I find a table of values for sF ?  It's not in any of my engineering reference material, and nowhere to be found on the web.  It's not in the JH Shop Manual either. 

Also, is there a nominal range to be expected of Cs ?

Perhaps they are in the files of JH Service Engineer, M.J. Hazelwood ?

Thanks,

Pete Bahr

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