71FJ40 Chevota (1 Viewer)

[71FJnick]

Page summary of topics:
15- twin stick, handbrake, and trans tunnel
14- Saginaw pwr steering, rear shocks
13- rear bumper, front leafs, shocks
12-front brakes
9-11 Front axle C&T- axle tear down
7- Alignment #1
6- QFT carb tuning, HEI timing/dizzy install
5- ball and claw axle rebuild, driveshaft tech
2-5 350 SBC clutch w toy hyd and SM420
1- introductions and plan

Hi, I'm new to IH8MUD and just bought my first FJ40! Super pumped about it and wanted to introduce myself.
I got a 'good deal', which basically means I took over someone elses project and get to make it my own.
As near as I can tell, its got a 350 swap, SM420 trans, stock transfer and stock axles with a SOA conversion.
After getting it running (yay new carb!), I'm now experiencing the clutch adjustment issues mentioned all over the place. Not sure how much of a build thread this may turn in to, I mostly want to get it running and driving, then go from there on some mods.

 

[RWBeringer4x4]

Welcome aboard! I have a 1975 Chevota project truck. It has a VERY old 350 conversion (that was, at some point, swapped for an even older 283). Currently digging through it an undoing all the ticking time-bombs the PO left me - mangled power steering conversion, blown transfercase, etc. I'm also converting it to disc brakes. They're easy trucks to work on, and a lot of fun! Clutch issues are up there for me too - my pilot bearing is on the way out. I'd imagine you're running a stock Chevy bellhousing with an adapter plate for the SM420 to the Xfer case. I can't be off too much help if that's the case - I'm running the Toyota transmission with a conversion bellhousing, which is a different animal. My understanding is that the issue arises from the Toyota clutch hydraulics not being able to move the heavier Chevy clutch components as far as they need to, making proper adjustment virtually impossible. I read something about using an early Toyota brake master cylinder in place of the clutch master cylinder, but I'm sure someone in your shoes will be able to chime in with more details. I'm planning on swapping what I have for a complete Advance Adapters setup down the road (when my bank account recovers).

 

[71FJnick]

Thanks RW, I saw your post on the '75, looks like a similar story of trying to fix the POs 'custom' work.
I've been doing a lot of reading on the clutch issue and the AA kit. I belive i have the AA bracket installed, but it looks a little wobbly, NOVAK adapters also makes a slave cylinder with bracket for 350s that I wanted to check out. looks like you can get a 7/8dia slave, then I'm thinking i can go with a brake master which has a 1" bore. That would give me a little more movement on the pressure plate. Anyway, the trans is coming out in a few weeks so between now and then I'll have to decide on a slave cylinder/bracket/pressure plate. I've heard about a low profile 11" centerforce clutch, so I think I'll head down that path.

 

[RWBeringer4x4]

There's a low-profile pressure plate/clutch combination. It's actually the pressure plate and clutch that the AA setup uses. Again, I'm not sure if it will be compatible with a stock chevy bellhousing (as opposed to a conversion bellhousing) but it's definitely worth a shot. A low-pro pressure plate should reduce the amount of throw required and might allow you to use the stock toyota hydraulics.

 

[71FJnick]

fixed my bezel... yup I'm a newb

 

[71FJnick]

Also got a tip from a local shop on a thermostat for a 350, I drilled 2 -1/8" dia holes to help burp the system. worked great, no fiddling around this time with burping the system.

 

[Downey]

Both the AA and Downey pressure plates are lower cone styles, and both have been machined to require less travel than a standard Chevy pressure plate. Pressure plate spring rate/poundage has nothing to do with the "travel" issue, the stock Landcruiser slave cylinder is probably rated at up near 4,000 psi operating pressure, and the hydraulics operates at close to a 40 to 1 leveraging factor, so the hydraulics do all of the work- - - you simply need a pressure plate your Toyota hydraulics can fully engage and disengage!!!!!

 

[71FJnick]

i wanted to get the truck running so I could figure out what else is wrong with it. bought a brake master for a 67 FJ40 and hooked it up to the clutch. Just had to make a custom pushrod and voila! working clutch. I may have just delayed the clutch replacement, but at least I can drive it around, set the timing and tune the carb... then maybe take it for a test drive to shake out any other bugs... so excited.

 

[RWBeringer4x4]

i wanted to get the truck running so I could figure out what else is wrong with it. bought a brake master for a 67 FJ40 and hooked it up to the clutch. Just had to make a custom pushrod and voila! working clutch. I may have just delayed the clutch replacement, but at least I can drive it around, set the timing and tune the carb... then maybe take it for a test drive to shake out any other bugs... so excited.

Out of curiosity, which pushrod did you customize - the one on the slave? Longer? Shorter?

 

[71FJnick]

I made the master about 1/4" longer than the stock clutch master, took a 100mm bolt and ground the head to round it off. Then it was still too short so i made a union and added abut 1/4" to it. for the slave, the PO had a pushrod made but it was too long, i fabbed up an adjustable rod for mock up, then trimmed the pushrod to size. Ended up being about 5-5/8 long.

 

[71FJnick]

I don't think the PO understood that a painless wiring harness is supposed to make wiring easier and cleaner.... Here's what I found

And here's the progress so far... Bach half done except for the final wrap

 

[Downey]

I'm not sure why your mis-matched master & slave cylinders are working, normally that set up would have your slave cylinder push rod moving 1/2 the distance it should, or having it try to travel twice as far as it can (with a radically stiff clutch pedal). If it's working, great, but don't make the mistake many make; having the clutch never fully engage (clutch disc always slipping, heating up, then burning out), or clutch never fully disengaging (you dragging/grinding through the gears because you never fully remove the pressure from the disc). Lots of Chevota owners try using stock Chevy clutches that take more travel to disengage than your Toyota hydraulics has, then they have the problems I mentioned, but since their rig is still somewhat drivable, they unknowingly claim they have no problem. Downey and AA don't make special Chevota clutches because they are in the make-pretend business, they machine special Chevy pressure plates to require less travel for full disengagement (using stock Toyota hydraulics) to actually solve a problem..

 

[71FJnick]

Thanks, good point. The pedal is about 20% stiffer than it was before.
I pulled the old master and slave apart and it looks like they were mismatched by the PO (master was smaller than the slave) probably why I couldn't get full clutch movement. Now I have the opposite problem, stuff pedal but more travel. During the test drive I heard some 'ting'ing sounds from the bell housing after the clutch disengaged. I think the pressure plate is already toast so I'll need a clutch anyway. I'll probably do the AA low profile, but I don't like the idea of have very little free play with the stock hydraulics so I'm thinking of using a Novak 7/8" slave with bracket and the 1" brake booster for the master. If the pedal is too stuff I'll go for a wildwood master... I think.

 

[Downey]

I don't know what the AA Chevota clutch cost (pressure plate and disc), my Downey Chevota clutch cost $252.00 plus postage (6"X14"X14", 38 lbs.). I still think your best bet is the same year model Toyota master cylinder and slave cylinder- - - matching set!!!!!!!!!

 

[srgould41]

Have you talked to Tor at Torfab (in Mukilteo)? He has lots of experience on these mods and might have some good suggestions.

Welcome to the madness.

 

[71FJnick]

Still haven't purchased any clutch components, I'm leaning back toward stock hydraulics and the AA low profile clutch. In the mean time I've been keeping busy rewiring. Tail section is complete, I ran into an issue with the rear tail lights.
They would turn on, then when the blinkers were on, they would blink completely off with the park lights on. Turned out to be a bad ground.
To fix, I ground away the line-x (or whatever was used) then made a nice ground wire with waterproof connectors. Problem fixed!

Painted over it with liquid electrical tape. Now onto the engine bay wiring

 

[shelfboy1]

chevy makes a stock short throw clutch it was used in 80s 2wd trucks and works good .prior to that i always had the flywheel drilled and used a stock toyota diafram clutch so i never had any clutch problems .except a couple i did before the diafram clutch came out then i use a scout or some other longer slave cylinder ,dont know why no one ever made a gm flywheel to fit toyota clutch ,to easy i geuss

 

[Downey]

chevy makes a stock short throw clutch it was used in 80s 2wd trucks and works good .prior to that i always had the flywheel drilled and used a stock toyota diafram clutch so i never had any clutch problems .except a couple i did before the diafram clutch came out then i use a scout or some other longer slave cylinder ,dont know why no one ever made a gm flywheel to fit toyota clutch ,to easy i geuss

I'm on it !!!!!

 

[71FJnick]

It was raining today and the cruiser sits outside so no wiring work. Decided to start cleaning up the rear doors that have yet to be mounted. Used a wire wheel to strip the hinges, the pained flat khaki, yup this will be another krylon truck.
Used 3m spray undercoating on the inside of the doors, that stuff is pretty cool and a decent price at the paint shop.

 

[kbahus]

Good looking start Nick, keep the thread going! Also if you need any parts let me know, I kept some smaller stuff and ended up bringing a couple rubbermaid bins of parts with me to Michigan.