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Well another you are not going to guess this......

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H82WRK

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but the car now won't shift! So much grinding and won't even go into gear.

A little background, the motor we purchased off John, a 948, had a smoothcase, my existing motor, also a 948 had the ribcase tranny. So in reviewing the forum the ribcase seems to be a better unit over all. So we decided to swap the smooth for the rib.

The original ribbed tranny was shifting in the car, some grinding in third and second but driveable with no problems. However we only got to drive the car about 15 to 30 miles before the engine shot and we replaced it with the "new" 948.

When we were mating the ribcase to the "new" engine we saw that the clutch on the "new" engine was in great condition. So we kept that on there and just swapped the cases smooth to rib.

Now the awful griding and can't even get the car to go into gear at all. More research determined that bleeding was in order.

So we tried bleeding, bled and bled and bled until we recirculated almost a whole bottle of fluid. So it has been determined that there is not air in the system that is causing this problem.

Next step check fork movement, my hubby showed me how to look at it, it is traveling the whole way.

One problem we did notice was a very slight leaking in the slave cylinder. However the slave was just rebuilt and the leaking is not so heavy to impact the system to this degree.

Which brings us to what is wrong? My thinking is that I will just pull the engine and tranny again (of course not me alone!) and put the smooth case back on as I know that it was running and shifting etc. when John had it. This solution would put me back on the road and driving in a very short time.

I am looking for a reliable engine and tranny, not looking for something that I need to build up. From what I understand the ribcase is an excellent choice should you want to add power, which I am not concerned about. Is my idea a good idea or not?

Hubby wants to tear apart the ribcase and figure out the cause of the problem. It is just in his nature and I am sure a lot of other people feel the same way. I don't really care what the problem is right now I just want a running driving car!

Any advice oh great little british car owners on this great wealth of information board??

Thanks so much!!!
 
The ribcase trans requires the thick engine backplate, the 948 requires the thinner, stamped, curled-edge backplate. If you put a ribcase on a 948 with the original thin 948 backplate, then the clutch spacing is screwed up and won't fully disengage the clutch. From your post it isn't clear if you are doing the correct backplate changes to match the transmission choices.

Glen Byrns
 
I think Glen has it...
 
I am thinking he might also. Either way it looks like this engine is coming back out of the car again, ARGH!
 
Glen's correct, but there's also more to it.
There are 3 pressure plates with 3 different heights. 3 release bearings with 3 different heights. You probably would have been OK had you matched up everything that was working. Compare the bearings and clutch as well, not just the backing plates.
 
Of course you can extend the slave actuator rod by about 1/4" and probably drive for a year or two that way.
The easiest way to extend it is to thread it 5/16-18 for a bit and screw on a 5/16-18 "coupling nut" (long nut). Has prevented more engine pulls than I want to count.
Bill
 
I have a ribcase and thin backplate. I don't know what else was put in, but it worked fine for many years. If you got the engine and trans together, it's probable that they were working together.

I think the first question one should ask is if the trans shifts with the engine stopped. In other words, is the ribcase in good enough condition to shift, and therefore is it the clutch that's the problem?

If it shifts when the engine is stopped, but not when the engine is running, the clutch could just be stuck from sitting a long time. Has the clutch been removed from the flywheel when the engine was out?

It could also be as Glen says and the clutch adjustment isn't correct due to incorrect plate, bearing, pressure plate. The only adjustment on these is to weld or cut on the pushrod between the slave cylinder and the lever.
 
But could the input shaft bottom out in the crank?
 
I have never had that particular thing happen to me (bottoming out) but a frozen clutch disk is VERY possible but easy to correct if the pressure plate is opening properly.
Bill
 
Just a bit more background. I am the 'John' to whom Rachael refers in her posts. The 948 that Rachael and Joe have transplanted in their '66 Sprite came out of my '59 Bugeye this past February. The '59 Bugeye had the smoothcase gearbox and the 948 slave cylinder, cluch plate, pressure plate, T/O bearing and clutch push rod. When they transplanted the 948, they used the ribcase that came with their '66 Sprite. I think Rachael indicated that they used my clutch plate. I am not certain which slave cylinder, T/O bearing, presure plate and push rod they are presently using.

Is it possible that there is a mis-match of slave cylinders, given the fact that the clutch master cylinders are different between 1959 and 1966? If this is only a pedal pressure issue on the mis-match, is it possible that it is a push rod length issue?

If I recall correctly, the backplate on the 948 that came out of my '59 was the thinner version, but I thought that later 948s came with a ribcase. If 948s came with a ribcase, was it a different backplate?

This '66 will be on the road soon. Rachael and Joe have worked too hard to stop now. I remind this forum that the combined ages of Rachael and Joe probably do not equal most of our individual years on this wonderful planet!

PS: Doc, I owed you a date of departure from NHS; 1970. Boot Camp; Great Lakes 06-29-70; Company 239.
 
When the engine is off, the tranny in gear, and the clutch in and the car will not move without the engine trying to turn I would suspect that the clutch disk is frozen to the flywheel.

So, several options to break it loose not the least of which is put it in second and push start about 20 MPH and hit the brakes hard. And I mean hard stall the engine, lock em up.

Of course I assume that you did not have the clutch out recently.
 
John /bcforum/images/%%GRAEMLIN_URL%%/iagree.gif , I think you are right about the slave cyl. pushrod length differences, and another strong possibility with the changes you describe would be with the throw-out bearing and/or throw-out bearing fork, as both of these parts underwent changes between the years cited as well!! Somehow, by "mixing-and-matching" Rachael and Joe should have all the correct parts on hand to make it work! /bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif
 
H82WRK said:
I am thinking he might also. Either way it looks like this engine is coming back out of the car again, ARGH!
Click to expand...

I really don't want you to feel discouraged by this, but mine went in and out 5 times before I got it right!
Keep repeating the LBC mantra, "This is a hobby." "I am having fun." "It will run soon!" and repeat this as you pull that engine again and work through the latest "glitch"
 
Re: Well another you are not going to guess this..

JohnK said:
This '66 will be on the road soon. Rachael and Joe have worked too hard to stop now. I remind this forum that the combined ages of Rachael and Joe probably do not equal most of our individual years on this wonderful planet!

PS: Doc, I owed you a date of departure from NHS; 1970. Boot Camp; Great Lakes 06-29-70; Company 239.
Click to expand...

heh. Kids. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif Gotta love it! Me hat's off to Joe 'n Rach. /bcforum/images/%%GRAEMLIN_URL%%/savewave.gif

Lackland, TX. in August 1970 for me.
 
Re: Well another you are not going to guess this..

It builds character.

However, if the pedal feels "good", that is if it feels like there is pressure pushing back on your foot, then the disk is most probably stuck. Push starting the car in second gear is a good starting point. Putting as much torque through the disk as possible is just a question of technique. In any case, hold the clutch pedal down. Try rapid changes from hard acceleration to deceleration and back.

I recently had a MZ motorcycle give me the same headache. I tried all possible methods and in the end pulled the clutch off. Found out it was installed by the PO incorrectly.
 
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