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 Posted: 05-27-2008 07:10 am
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Dan Eiland
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I installed the engine, transmission and driveshaft into my JH for a trial fit today. Now that I have the adapter for my Ford T5 5 speed transmission and the modified driveshaft I needed to install everything in the car to check the fit. I found that I had to modify the mount for the clutch return spring and I had to modify my custom made clutch cable mount. Everything seems to be working fine without any interference issues. I installed the pedal box and hooked up the clutch cable to see if it was going to work and that is where I seem to have an issue. When I depress the pedal it has almost no resistance and doesn't disengage the clutch. There shouldn't be much room between the TO bearing and the pressure plate (1/16th inch), but I can move the clutch fork forward with my bare hands. I took everything apart thinking something came loose and everything was still attached. Open to suggestions.

Dan

 

 

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 Posted: 05-30-2008 11:16 pm
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Bob McDonald
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Hi Dan

I found that there are 3 different ford throwout bearings so depending on your

set-up you may need the longer one

Bob

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 Posted: 05-31-2008 04:15 am
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Dan Eiland
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I should have explained that I am using a Ford clutch disc that has the same dimensions as the original JH disc but has the Ford center which I needed to match the transmissions input shaft. The clutch fork, thrust bearing and pressure plate are all JH or Lotus and the flywheel is a custom made aluminum flywheel. The flywheel has been balanced and surfaced to make sure it was flat. All parts were balanced seperately and then again as a rotating assembly before installation. Hope this helps.

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 Posted: 06-02-2008 10:13 am
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Harkes
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Hi Dan,

i have had a similar thing when fitting my supra gearbox and hooking up my clutch cable and custom made clutch cable bracket.

Please make sure the clutchcable is fixed and attached at the front of your engine  (underneath at the sump) so prohibit the cable from moving when drepressing the clutch.

Determining the issue: when fully depressing the clutch; then what is the TO bearing's position? Good: TO pushes in the fingers of pressure plate- should disengage clutch. Not good: TO just touching the fingers - not disengaging clutch.  Behind the fork you can adjust the clutch cable operation. I'm sure you have already adjusted this, but where are the nuts located now? I'm assuming that it is adjusted in the direction towards the cable where you can't go further? That and the fact that there is hardly any resistance on the pedal, makes me believe there might be an issue with both your mounts (1 clutch return spring, 2 cable mount)

Start with  2) cable mount

The fact that it doesn't disengage the clutch when clutch pedal is fully depressed means (assuming you tried adjusting the nuts at the end of the clutch cable) the TO is not pushing in the fingers of the presure plate, which means the fork must be pulled further toward the front of the car.  Most likely then that your custom made clutch cable bracket is too close to the fork.  To fix: unhook the cable return spring, unhook the cable from its mount, put the nut of the adjuster in the middle of the bolt, have someone depress the clutch pedal, check to see if TO bearing pushes in fingers of pressure plate and disengages clutch.  Most likely you will find out that your cable bracket must be positioned further to the front of your car by one 1 inch or less.

I had to fix a piece of steel 2 cm thick and that did the trick! (i can take/send you a picture of my bracket if you want)

If it now disengages the clutch and there is still hardly any resistance on the cable:

Then check 1) clutch return spring

You said you had to modify the mount for the clutch return spring. It could be it is located too much forward because of which the spring has too much play? This would explain why there is hardly any resistance. To increase resistance on the cable you need to position it further back or replace the spring by a stiffer/shorter one. (quite tricky to find a good replacement spring with the correct length and tension!). If you use the original JH spring and bracket then you could shorten the bracket.

Good luck and i'm very much looking forward to see more pictures of your fantastic project.


Erik

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 Posted: 06-02-2008 02:54 pm
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Dan Eiland
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Thought I would update where I am in the clutch operation issue. I have discovered that the rubber dust boot was restricting with travel of the clutch fork. I removed the dust boot and the clutch will now disengage. Problem now is the angle of the fork when the bearing makes contact with the pressure plate. I have moved the pivot pin forward about 1/4" which has helped but when the thrust bearing contacts the pressure plate and I back off a few mm, the clutch fork is 8 degrees forward of perpendicular. The fork should be either perpendicular or 5-8 degrees behind perpendicular. So it looks like I just need to increase the length of the pivot pin to get things working correctly. Not sure what I'm going to do about the dust cover. 

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 Posted: 06-02-2008 04:31 pm
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Bob McDonald
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Dan

I have the same setup as you except the throwout bearing is ford and the

healey forks pins ground out to fit.That's were the 3 different length ford bearings

are handy.that way I was able to use a 5-speed pivot pin and stock cable and

mount.It's been working great for 2 years with no problems.

Bob

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 Posted: 06-02-2008 06:12 pm
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Joel
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Dan:

I would be interested (and I'm sure there are a lot of other folks who would too) in knowing what you did for the bell housing.  When you're done with the project would you mind posting some pics?

And the rest of you with alternative trannys - could you give more details too?

I'm thinking of just going with the Conversion Components bell housing.  But, I'm interested in knowing the alternatives. 

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 Posted: 06-02-2008 08:36 pm
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Bob McDonald
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Hi Joel

I wrote out what I've done and sent it to Greg but I didn't have any photos

so it was probably hard to follow and I didn't keep my measurements.

All I can tell you is I milled a 4 speed bellhousing down and routered out

a 5/8" aluminum plate to match the mustang 4cyl transmission

Then stood a spare engine on end with the cut bellhousing pointing up

then installed the transmission and plate ,centering the input shaft to the crank

Tack welded the plate to the bellhousing and removing to weld completey

so if you measure everything from stock it is possible to make yourself.

Bob

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 Posted: 06-03-2008 02:09 am
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Dan Eiland
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Bob,

Wish I had known. I hate inventing things myself if I can copy what someone else has done and it works. What bellhousing did you use to make yours work? I'm using the early Lotus Excel bellhousing that was originally used with the Toyota tranny. I'm using the the 94-97 Mustang transmission that had the longer input shaft and the shifter comes out in the original location with no modifications to the tunnel. Still had to have an aluminum adapter made to connect the transmission to the Excel bellhousing. The machine shop modified my original pivot pin from my 4 speed when they should have left it alone and just modified the adapter it screws into so it is in the correct location. At this point I may just cut the threaded part off the pivot pin and drill a hole into the bottom and then tap it to fit a stud. I can then mount a stud into the pivot pin mounting location on my adapter and thread the pivot pin onto the stud making it adjustable. All I would need to add is a nut to lock the pivot pin in place once I find the ideal location. You can see photos of what I'm doing and follow my project at the JHPS Photo Page below:

 http://jhppg.com/gallery/Texas-Critter

I'll probably play around with the transmissions gear ratios later so they'll better match my engines performance curve. If anyone would like to see more photos please let me know and I'll post whatever you would like to see or whatever interests you.

 

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 Posted: 06-03-2008 06:43 pm
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Bob McDonald
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Hi Dan

Your set-up looks great.

I used the ford throwout bearing with the healey forks [grounded the pivot points]

so I didn't have to machine transmission and with the unit bolded toghther the

pivot pin location was marked and an aluminum spigot was welded to the bellhousing

that was threaded for the pivot post so the height was the same as stock.

I didn't want any lock nut or adjustment that could cause problems later.

Using a modified 4-speed bellhousing allowed me to use the stock clutch

cable bracket and return spring.

But your shifter location and gear ratios will be better than the 4 cylinder tranny.

Bob

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