MQ V8 CLUTCH PROBLEMS

[junior]

Hi gents, need some advise on clutch set ups in MQ swb's with v8 conversions.
As most of you already know i rebuilt the red rig with the 307 chev and on the test run i could'nt get any gears.I put it back the exact way it was removed so i assumed that the diaphram in the pressure plate may have broken.
I then got a new clutch kit for it (same as old one).
Once again crunching trying to get gears (to much push),as i was playing with the adjustments the seal in the slave cylinder split so i replaced the slave aswell.
Anyhow got this sorted and tryed to get gears with no luck,if i pushed the pedel half way it was ok so i adjusted it (pedel and fork)until i could get gears with full push of the pedel.I then fitted a return spring to the clutch fork.

The problem i now face is the pedel feels crap and engages mm's from the floor and it still has the occasional problem going into gears.

Would like to know if i should fit a larger bore master cylinder/slave cylinder so i dont get so much push at the fork.

I will try and get some pics of the master and slave cylinder as i have no clue as to the type or model from which they came,if the camera decides to work that is.
Sorry for the large thred

Advise would be appreciated

thanx
jnr

[V8Patrol]

Its a real biatch of a thing to set up right ......then when ya think its finally right the damn thing fugs up again on ya !

simplest way is to fit a new master and slave right from the very start, this way you know that they are spot on.

then its trial and error to get the adjustment right. Usually I make a new rod that goes between the slave and the fork and and start off with it 10mm longer than the std one that came out of the setup, if that fails then I trim off 2 mm and try again, if that fails then I trim off a further 2 mm and try again, and so on......

A set of calipers will help here in keeping the length some what accurate and when its right then make another rod 2mm longer than the one thats working and stow it in the glovebox for future use.
The new clutch pak will settle in and thats where your problem has come from so now it would be the time to fit the 2mm longer rod to the system and the problem should be solved.
This will depend on which pressure plate you are using as to the length of the rod, even the same pressure plate from different manafactures will vary ever so slightly for the rod length, you may need to make your trims 1mm instead of 2mm.

I have tried to make rods that are adjustable ( threaded with nuts & locknuts ) but in some conversions it is imposiable to get a spanner onto the nuts for adjustment..... so its the simple trial, test, trim, trial system that seems to be the best way around the dramas.....

its the nature of the beast

Kingy

p/s
after ya have done a few V8 conversions ya end up with a fair collection of rods, funny thing is that they never seem to work on the next one ya doing

[V8Patrol]

Another thing I forgot to add........

There has been the odd occasion that it wasn't the rods fault too .....

check the actual clutch peddle for play in the hinge pin .......
after 20+ years of being pushed in n out a couple of million times and more n likely never had any oil/grease since the factory did it, the hinge pin WILL be worn as will the hole ( which is more like a slot by now !! ), this allows adjustment to "disappear" as the pin slides back n forth in the slotted hole !!

Simply fit a larger pin ( the shank from an old 14mm bolt works well !! ) and drill the hole out in both the peddle arm and the rods attachment plate to suit the new pin making it a "neat fit".
Believe it or not but in some cases I have gained in excess of 25mm extra peddle travel by doing this fix.


And in sheer desperation .....
there has been 1 occasion where the rod that runs between the master cyl and the clutch peddle ( through the firewall ) was bent, I had this happen once and it was caused by a heavy duty clutch plate that bound up when the peddle was engaged fully. I simply fitted a new rod made with a larger diameter shaft ....... fixed !!

Kingy

[junior]

Hows things Kingy,thanx mate for ya advise.Ive checked the pedel box and rod and it appears to be ok.
The main problem im having is way to much push on the fork,the pressure plate fins push into the clutch plate.I backed the adjustment on the rod right back and thats when the slave piston poped out and split the seal .
I then had to back the adjustment on the pedel box push rod right off aswell and this lowered the pedel somewhat.
I then fitted the return spring to pull the slave piston back to start of the bore and this is whats causing me grief,two thirds pedel play before the thrust bearing is even on the presure plate.
From what i can see the master cylinder is not the original unit due to an additional bolt stud underneath it,as to what type i have no idea.
Tell me,if i fit a larger bore master cylinder will this give me less push or more at the slave end ?
Id like to retain the slave if i can as this has already been replaced but if it comes down to a better pedel ill replace the damn thing.
Youv'e said to replace the lower rod but in doing this it will cause the fork to move away from the pressure plate and im back were i started to much free play,correct?
Im not 100% sure but i think this may be a dellow housing as it has the slave cylinder mounted upside down, i read that somewhere from memory.
Regards
jnr

[J Top]

Smaller M/C bore,lighter pedal but more pedal travel required for clearance.
J Top

[V8Patrol]

Tell me,if i fit a larger bore master cylinder will this give me less push or more at the slave end ?

Think of the master cyl as a syringe that a Dr is about to pump into ya butt....
A big bore M/C will push more fluid to the slave therfore more slave travel but with a slightly heavier pedal ...... opposite for smaller M/C obviously.

Youv'e said to replace the lower rod but in doing this it will cause the fork to move away from the pressure plate and im back were i started to much free play,correct?

Depends on which way you go with the length of thr throw rod on the slave,
A longer rod will push the fork onto the pressure plate more ...... and again the opposite will happen with a shorter rod.

From what i can see the master cylinder is not the original unit due to an additional bolt stud underneath it,as to what type i have no idea.

Mmmmmm this may be the cause of your grief......
Last M/C I bought was a generick "Master Parts" and its works fine & bolted straight up ..... maybe a new M/C may help but the one you have is obviously working...... perhaps a little to well !

I backed the adjustment on the rod right back and thats when the slave piston poped out and split the seal .
I then had to back the adjustment on the pedel box push rod right off aswell and this lowered the pedel somewhat.
I then fitted the return spring to pull the slave piston back to start of the bore and this is whats causing me grief,two thirds pedel play before the thrust bearing is even on the presure plate.

Hydrolic clutches are biatches to adjust when doing this sort of conversion and I've found that even a hacksaw cut thickness can make tha world of a differance to the way the fork throws. Thats why I said use a set of calipers to measure the length of the rod as you trim it back from its over length starting point.
I have reread what I posted up and have done likewise with your posts and perhaps I wasnt quite specific enough in the "rod trimming" details, I also gather that some of the adjustments you have done are fairly big in regards to the millimetres you have added/removed.
It will come down to minor trims of the clutch fork push rod and I mean 'minor", caliper measurements, and even a file may be nessecary to get that right length for the rod in your case

Its a tough call as to which way to point you for a cure, either the clutch fork push rod adjustment way or to send you under the dash and do minor adjustments to the clutch pedal to master cyl push rod.....
Perhaps the later of the two may be the go as its an unknown M/C and somewhat easier to get to than working down on the bellhousing area.
By the sounds of it you may allready have a large diameter M/C and this may be causing the problems at the slave end of things.

Which ever way you go ...... Just remember ..... MINOR ADJUSTMENTS

Kingy

[junior]

Thanx guys, Ill try and get some pics and details of the type of M/C and S/C im running and the bore size also.


I understand what ya say'n Kingy about the rod length but the thrust bearing should only have a mm or 2 spacing between it and the pressure plate fins so shortening the rod would pull the fork back and cause that gap to widen some what,making it longer would push it to far.


Ill look into the M/C type seing as though yours is mounted to the original studs,mine may have been a fubar from the begining.


Might have to go a smaller M/C as JTop and yourself have mentioned,seems like the only way to get good pedel with limited push.


While ive got you Kingy,do you run a snorkle set up for your duel fuel V8 converted Mq's
I'd like to set up twin snorkles but im wandering how to set it up for duel fuel as a mixer has to be retained,i was thinking about getting a large air cleaner box fabricated so it dosn't require a new air cleaner every trip and have the inlets from each snorkel to either side.
What you think


Thanx Again
Jnr

[V8Patrol]

While ive got you Kingy,do you run a snorkle set up for your duel fuel V8 converted Mq'sI'd like to set up twin snorkles but im wandering how to set it up for duel fuel as a mixer has to be retained,i was thinking about getting a large air cleaner box fabricated so it dosn't require a new air cleaner every trip and have the inlets from each snorkel to either side.
What you think.

No I dont run a snorkle at all on any of the MQ's here !
My Main offroad rig is plenty high enough not to really worry about having a snorkel, the idea is good but with a soa and 38 swampers then the aircleaner is just above the 5' mark anyway.
If I was to drive water any deeper than that then the rig would float away so it was pointless to fit one.
I do however run a modified "splash shield", it covers from the very top of the aircleaner to just above the inlet manifold. This stops 99% of the water ever getting near the aircleaner in the first place.
The LPG mixer sits directly ontop of the rochester carby with a 3" addaptor between the mixer and carby. The "splash shield" is made form ( and you wont belive this either ... ) a cooks "boiling pot " !!, the pot is alloy and all I did was to cut it to the desired height and then cut a hole in the bottom to allow the fitting of the 45-70 series mixer I run.

I found that the water problem when xing rivers was largely attributed to spray comming off of the engine fan initally but even with it locked in place then the other belts ( power str, alternator & air pump ) still provided enough spray to water log the aircleaner to the point that it would enter the engine.

A mates MQ with a 308 fitted and not SOA'ed had the same dramas with water on one trip we did, after fitting dry aircleaner we wrapped the front exposed part of the aircleaner in plastic covered cardboard and continued on.......... we hit much larger water obsticles and it never suffered from water intake problems at all after the cardboard was fitted.

Juddy and I used the same theory on the General Lee and its aircleaner setup. if you have seen the pics in the members section you can clearly see the water we had to cross and we never even covered the radiator nor did we disable the engine fan which is NOT a clutch type fan but rather a direct driven type !!!
The General never suffered from the water xing at all yet others did have problems with wet aircleaners.

As for fitting a snorkel i dont have the need but I'm sure there are those that wouldnt be without one for one reason or another. I guess all I've seen of snorkels is nothing but trouble and the thing that gets me wondering the most is the number of rigs with snorkels fitted that I've pulled out of mid river crossings after they have become flodded.

I use a simple yet practicle approach to water and engines,
cover the air cleaner as much as possiable from water splash,
use "Vasoline Petroleum Jelly" around each end of the spark plug leads,
use a small ziptie to seal the rubber boots on the ends of the sparkplug leads to the actuall lead,
use "Vasoline Petroleum Jelly" around & in the join between the dizzy and the dizzy cap.

the problems I see with snorkels are ..........
which way should the opening on the snorkel point forwars or backwards,
which tree limb will wipe the snorkel end out,
how does one seal it up completly yet maintain the abillity to remove it,
the horsepower loss form an elongated intake air system,
etc etc ,

I like my $3.00 "cooks pot" form the Salvos shop

Kingy

[Paps]

I haven't read all the replies you have been given but I shoe horned a toyota dyna gearbox into a landrover behind a valiant hemi. I found the trick was to use as much of the pressure plate maunfacturers actuating gear as possible, ie the throw out fork (Length and fulcrum point position) and slave cylinder and master cylinders (inside diameter) the same as the pressure plate manufacturer specs. I also initially had the problem of over throw and the pressure plates were only lasting 10,000 K's.