43 replies to this topic

[Chris1992]

Hi guys,

So, just to set the scene, I have a completely brand new engine, brand new straight cut gearbox, with straight cut drops. (Rod change selector. Pre-verto clutch)

I have a pretty much new OBP pedal box with integrated master cylinders, with new slave cylinder, new clutch arm, new clutch plate, new clevis pins, new braided lines, etc.

The issue I'm having is getting it into gear when the engine is running. It's buttery smooth when not running though. I can get it to go into gear maybe 60% of the time, but it seems to stick a lot, like I have to force it, and sometimes it won't go at all. 2nd gear is the most stubborn.

In terms of adjustments, I have followed all the guides I can find on line. Set the arm 0.20mm off the stop bolt, press clutch in, wind lock nuts up to the clutch housing, release clutch, wind in an extra half flat, job done. But still the issue persists.

In terms of experiments, I have tried lengthening the rod that goes from the top of the arm into the slave cylinder, and I have tried adjusting my pedal to give more travel (something I am able to do with my pedal box), but it is STILL troublesome.

I'm pretty certain that in terms of hydraulics all is well, as it doesn't seem to make a difference how far I press the peadl in as long as it has engaged. The biting point is also relatively high and doesn't seem to change.

The only thing I can think of now is the gear selector itself. I'll admit that this is the one part I haven't refurbished, as up until my last engine came out, it was fine, but who knows. Could this produce the symptoms I'm describing?

Alternatively, is this just how straight cut boxes are? Will it get smoother as I put some miles on it and it gradually beds in?

Sorry to ramble, I just wanted to give as much detail as possible.
Any advice would be much appreciated!

Cheers
Chris

Edited by Chris1992, 10 April 2021 - 06:07 PM.

[nicklouse]

How much is the arm moving at the slave?

 

what bore size is the clutch MC?

[Chris1992]

How much is the arm moving at the slave?

 

what bore size is the clutch MC?

 

At least half an inch, maybe more. 

 

Hmm that's a good question. I can't remember off the top of my head, and OBP have changed their website so I can no longer see which one's came with it. I'll get out there this eve and report back. 

[nicklouse]

 

How much is the arm moving at the slave?

 

what bore size is the clutch MC?

 

At least half an inch, maybe more. 

 

Hmm that's a good question. I can't remember off the top of my head, and OBP have changed their website so I can no longer see which one's came with it. I'll get out there this eve and report back. 

 

That should be enough movement.

 

what gear kit is it?

[Chris1992]

That should be enough movement.

 

 

 

what gear kit is it?

 

 

The engine was built for me by Specialist Components, but on the spec list it says 'Minispares straight cut'. So I'm assuming it's an off the shelf unit from Minispares

[Spider]

One other item to consider here is the Primary Gear. Is it being pinched by the Flywheel ?

 

Given your description, I can't see it being the Gearkit or the Shifter, it does tend to point to the clutch.

[Chris1992]

One other item to consider here is the Primary Gear. Is it being pinched by the Flywheel ?
 
Given your description, I can't see it being the Gearkit or the Shifter, it does tend to point to the clutch.

I honestly don't know where to turn now mate. I've already had the engine out twice to sort other things so I really don't fancy taking it out again! I'm not too family with the inner workings myself, hence why I paid someone else to do it.

[Cooperman]

Chris, if you can find my 'Clutch Drag Fault Finder' on here it lists all the possible reasons in sequence.
It might help.

[Chris1992]

Chris, if you can find my 'Clutch Drag Fault Finder' on here it lists all the possible reasons in sequence.
It might help.

Ok thanks mate I'll have a search

[Chris1992]

Something else I forgot to mention. I get absolutely no grinding or crunching at all.

On the occasions it goes into gear fine, then it's nice and smooth. Then other times it will need more force, at which point it will suddenly 'click' into gear. No grinding, bit it doesn't feel right.

Then occasionally it won't go into gear at all, and I'll have to try a different gear first and then go back to the one I was just trying, and usually that will do the trick.

[nicklouse]

Ok you have checked for anything stupid in the shifter assy?  Nothing changed there? Roll pins good? Locating pins not pushed out allowing the shifter to move incorrectly?

[Spider]

Something else I forgot to mention. I get absolutely no grinding or crunching at all.

On the occasions it goes into gear fine, then it's nice and smooth. Then other times it will need more force, at which point it will suddenly 'click' into gear. No grinding, bit it doesn't feel right.

Then occasionally it won't go into gear at all, and I'll have to try a different gear first and then go back to the one I was just trying, and usually that will do the trick.

 

With new Baulk Rings, if there is clutch Drag, it's next to impossible to get the Gears to Grind.

How is it selecting reverse though ?   As that has no Baulk Ring, that will Grind. Does it go in to Reverse with no Grinding, or is there possibly a bit of a Grind and a Thump ?

[weef]

Are you having this problem when actually driving the car or just sitting in the workshop ?

[Shooter63]

I had this trouble on my Mrs mini, it turned out to be wear in the rod change box ( the bit with the gear stick in) itself, I put a different one on with new mounts and problem solved, try it before taking the engine out again, you have nothing to loose.

Shooter

[Chris1992]

I had this trouble on my Mrs mini, it turned out to be wear in the rod change box ( the bit with the gear stick in) itself, I put a different one on with new mounts and problem solved, try it before taking the engine out again, you have nothing to loose.

Shooter

 

Very interesting! I had convinced myself that this wouldn't be causing the symptoms I have, but I'll get the car up in the air and take the plate off the underneath to see if there is any wear. Like I mentioned above, this is one of the few areas I have not refurbished, so I was hoping it might have something to do with it. 

 

Are you having this problem when actually driving the car or just sitting in the workshop ?

 

I haven't driven the car yet, this is only from idling it in the garage. I am going to take it for its first test drive up the road this afternoon though so it will be interesting to see if that makes a difference.

 

 

With new Baulk Rings, if there is clutch Drag, it's next to impossible to get the Gears to Grind.

How is it selecting reverse though ?   As that has no Baulk Ring, that will Grind. Does it go in to Reverse with no Grinding, or is there possibly a bit of a Grind and a Thump ?

 

 

Interesting. Reverse is absolutely perfect to be honest. No thump, and no grind. Occasionally there is the faintest tiniest bit of a crusnch, but nothing more than you would expect from engaging reverse in any car. 

 

Ok you have checked for anything stupid in the shifter assy?  Nothing changed there? Roll pins good? Locating pins not pushed out allowing the shifter to move incorrectly?

 

the roll pins were nice and tight when I fitted them, and there doesn't seem to be too much excess play in the rod change shaft, but this is next on my list to completely overhaul and replace if the problem persist. 

 

-----

 

Just to provide an update. This morning I went to have another play, and I have found that if I'm a bit more forceful, I can in fact engage all 4 gears every time I try. Maybe I was being too gentle? Is this a characteristic of a straight cut box? Or indeed a brand new box that has not been bedded in?

 

2nd gear is the one that offers most resistance, almost having to 'click' into place instead of the smooth change I've grown used to. 4th can sometimes stick a little too. I'm going to test drive the car for the first time this afternoon, only a quick jaunt up the road and back, so it will be interesting to see how much difference this makes.