Hydraulic clutch swap time

[MTCK]

I suppose I could throw this at the end of my lift thread, but I'll try to do a good write up with pics in case anybody else wants to do this. I haven't had any luck finding a factory pedal setup, but after looking at it quite a bit I think I can modify my stock pedal assembly and make it work.

For those not familiar, the truck is the one in my sig line, 1977 K10 with a SM465, pretty much factory drivetrain. Shifter linkage hits my extended upper front shock mounts which is driving this mod.

First I'll gather up some parts... Napa has the master and slave cylinders about 400 yards from my house, so that is easy. Prices don't seem too bad, about $45 each. They want $95 for the line though,so I think I'll probably make my own 12mm x 1.0 to -4 AN with 2' of hose I can build for about $40. I might also swing by the outfit that makes all the custom hoses for heavy EQ for the company I work for and see what they can do...

Napa master cylinder part # NCF 72128
Napa slave cylinder part # NCF 73117
Napa hyd line part # UP 38559
Advance Adaptors Bracket# 715535

I'm not sure if the master will come with a reservoir or not. Am I forgetting anything else? I'll probably order what needs ordering tomorrow so I doubt I'll get everything this weekend.

The truck is way to fun to drive with the lift and I'm not going to let this wait or thrash my drivers front shock so this swap needs to happen!

[argonaut]

Marcus,
How do you like the advance adpters bracket for the slave? I bought one for my hydraulic clutch setup, but I'm not thrilled with the design of it. Was thinking of returning it and fabbing my own.

I also choked on the cost of the hose. I went with a wilwood master and converted to 3/8-24 inverted flare and a -3AN stainless braided hose with adapter fittings.

I'm anxious to see pictures of yours installed.

[MTCK]

Hi Jason,
I haven't ordered the parts yet, so I can't weigh in on the adapter. I'm also open to other suggestions! The price seemed right on it, and I don't have much in the way of fab tools at my disposal. Whatever I do I'll post up a full report with pics.

[argonaut]

$40 bucks ain't bad for the adapter. And honestly it is probably fine for the application. but being an anal retentive and nit picky mechanical engineer, I'm often not happy with things as they come

I'll also share pics when I fab my bracket. It is actually a very simple design that I've already drawn up. Maybe I'll make two when I get around to it in the next coupe weeks.

[MTCK]

Hahaha well that makes sense regarding your profession. It'll probably work fine for this civil engineer, but that's why you make weapons and I make targets...
Posted via Mobile Device

[MTCK]

PS let me know if you need a beta-tester!!!
Posted via Mobile Device

[DirtyLarry]

Marcus,

I have quite a few pictures of my hydro clutch swap in my NV4500 swap thread from a couple years ago. I am sure you can make the mechanical clutch pedal assembly work but it would be well worth the time to find a hydro clutch and brake pedal assembly as they are quite a bit different and much better built than the older mechanical style pedals. The hydro pedals actually have two brackets that go to the firewall that also serve as the mounting studs to mount the master cylinder. This is a great design as there is no oil canning affect when stepping on the clutch and fully ties the pedals to the m/c. The hydro clutch pedal assembly just flat out works better than the mechanical IMHO.

I am running the AA hydro clutch slave adapter and love it. It is rock solid with zero bracket movement and the clutch engagement on the K10 works better than my bone stock Silverado. On the other hand, another member here that lives down the road from me just installed a NV4500 in his truck with AA pieces and his slave brackets moves all over the place and we haven’t figured out why. It is mounted just like mine but acts so much different. Dunno why his is so wobbly?? Not sure if AA changed the bracket design or what.

To answer your question if the m/c comes with a reservoir…. the answer is it depends. If you go with the 85-87 design the reservoir is remote mounted near the wiper motor. If using the later style the reservoir is part of the m/c. The problem with the later style it is not compatible with the 87-87 (91 squares) pedal assembly.

Heck, if you plan on keeping your truck a SM465 and you can wait a month I will be pulling the hydraulic SM465 out of the Burb to replace it with a NV4500 and can hook up you up with the Burbs SM465 hydraulic bellhousing if you feel like pulling your trans. The slave mount is cast into the bellhousings on stock hydro 465’s and really would be the “right” way to add hydro to a SM465.

[DirtyLarry]

Here are some pictures of the differences between the AA slave bracket vs. a stock SM465 hydro bellhousing with the slave bracket casted into it.

AA Bracket 715535 that fits an older mechanical SM465 bellhousing or NV4500 AA bellhousing . I’ve had great luck with this bracket. It bolted on easily, feels rock solid and has worked great for 12,000 miles so far. I am often surprised how well the clutch pedal throw feels and as smooth as it is. It works so much better than my Silverado HD that only has 55K miles on it. Member lytemup454, not so much. We need to figure why his AA slave bracket moves so much when engaging the clutch. He might have gotten a hold of a stiff slave or something.

Freaky looking little bracket


Bracket on a NV4500 bell behind the 8.1L in the K10. The heat shield on the slave must be removed for clearance though. Even with it gone, I haven't noticed any side affects even while wheeling around Utah on 110 degree days.







This is an original SM465 hydro bellhousing with the slave bracket casted into it that is in the Polar Bear Burb. Huh, looks like the slave sprouted a leak since I looked at it last. Well, SOB!




The factory SM465 bell puts the slave at an angle. It looks like things are bent but it is the way it is designed.



Hydro pedal box vs. non-hydro. Hydro on the left


85-87 ( up to 91 squares) reservoir location. I did a hydroboost swap at the same time as the NV4500 swap just because the truck was in bits anyway.


For the m/c mounting I made a template from the hydro pedal truck at the boneyard. Made drilling the m/c hole in the correct location much easier. I found drilling the hole was much easier from the inside rather than engine side of the firewall. Also much easier with the steering column out of the way.


Hope this helps

[americanmusc1e]

When I did my hydraulic clutch conversion on my 70 2wd I just used a SM465 bellhousing out of a hydraulic truck (89 i think) and used the factory slave, master and even a clutch line from autozone. The only hard part was setting up the pushrod (i used a modded brake pedal pushrod from a similar year) and the master cylinder in the firewall for effective release with minimal effort.

This is how it looked before I moved it up a little. In this location it had way too much travel and way too much effort. The silver home fabricated bracket is for the master cylinder. it contains the two studs that poke through the firewall to mount the master. it also makes sure that the clutch pushrod has no chance of falling out if the clutch happens to spring back too far.

I just re-did it about a week ago and got it set up all perfect. Now I'm switching to a different cab and I've got to move it again...

[MTCK]

Thanks for all the great pics and insight, Larry. I was planning on sandwiching the firewall on either side with pate where the master mounts, but was still concerned about it not being tied to the pedal assembly. I've had a few hydraulic clutch rigs and the pedal gets HARD when it's -50F out. Sometimes you push a lot harder than you would like to... I am headed to Anchorage this weekend, and they have several more bone yards there, so I'll look there and see if I might luck out on a set of hydro pedals. Also great pics of the stock SM465 bellhousing. Let's talk timeline when I get back! The adapter will work, but I love having factory parts when they are available.

Thank you as well, AmericanMusc1e. That's pretty much what I was thinking. I was going to measure the pedal stroke and do a little trig to get the right measurement from the pivot point to use the whole stroke on the MC. Do you rub at all on that nut? It looks like a tight fit.

[americanmusc1e]

Originally Posted by MTCK

Thank you as well, AmericanMusc1e. That's pretty much what I was thinking. I was going to measure the pedal stroke and do a little trig to get the right measurement from the pivot point to use the whole stroke on the MC. Do you rub at all on that nut? It looks like a tight fit.

The interesting thing I found on mine is i don't actually need anywhere near full stroke for the clutch to release. I don't remember how much stroke I have now, but I think I ended up moving the firewall mount and pedal mount about an inch up...

And yes.. I originally had problems with it binding at full depression. I fixed that by enlarging the hole slightly when I moved the master cylinder the other day.

[MTCK]

FINALLY found a factory pedal assembly in Ohio and it just got here today. It is complete with a factory master and slave cylinders, hard line and reservoir. The whole setup needs to be hit with the scotch brite pad and some paint.

[Oilbrnr]

I just dropped $160 today at lunch with NAPA ordering all the parts to rebuild my pedal assembly including master/slave/line$$$/bushings/pads for my upcoming LS swap in my '77.

Can you please make a nice .pdf template of where to drill holes in the firewall?

Thanks!

[MTCK]

I was hoping you had a PDF template! Larry has a nice cardboard one in his pics. I think 85 and up trucks have the dimples whether auto or manual. I was planning on finding one and making it that way. When I'm done ill happily scan it and send your way.

Are you keeping the SM465?
Posted via Mobile Device

[Oilbrnr]

For now the 465 will stay. I want to get the LS swap done then put a 14FF in the rear and maybe a D60 up front if I can find one at a decent price. Not that I really need it over a 44 but something is going to have to give going to 8 lugs.

After that is the nv4500 conversion. However, I'm keeping my eye out on CL for the elusive round 208 or a 241 from a 88+ burb or K5. The ironic thing, the pedal and bellhousing truck that I got the hydraulic setup from, had the round 205. Unfortunately not by the time I got to it!

Maybe Larry kept that piece of cardboard! Or we could send him back to the squarebody boneyard and have him make another.

[DirtyLarry]

Originally Posted by Oilbrnr

Maybe Larry kept that piece of cardboard! Or we could send him back to the squarebody boneyard and have him make another.

I looked around the shop this afternoon and no dice on the template. Pretty sure it got tossed after the project was wrapped up. I'll have to make another next time I head up to that honey hole. Might be a while though as I am headed out next weekend for the Death Valley trip. Will be gone a full week and two weekends.

[MTCK]

Ah, no worries Larry, I've got a plan! I'll scan in the template when I'm done if anybody wants I can email a PDF. Have a good trip. I know I don't have to tell you to take lots of pictures! Still using your spot?

[DirtyLarry]

Good deal. At least we'll have a nice PDF floating around for the next guy.

Ya, you can count on us to get lots of pictures. I’ll send you a SPOT link before we go. Here is a link on trip prep stuff.

[MTCK]

Made a little progress today. Got the hydro pedals cleaned up, painted and new bushings installed. My firewall is still covered in the infamous black crap, so getting the brake booster / steering column pass through off was a treat.

I picked up a new master and slave from Napa. Didn't like how the ones that came with my pedals looked and I only want to do this once. I removed the heat shield on the slave and drilled out the holes to match the 7/16 on the AA adapter.

More tomorrow.

[rgunlock]

Pedal assembly cleaned up nice. Do you know what year they came out of?

[MTCK]

I believe the guy said they are out of an 85. They were pretty rusty!
Posted via Mobile Device

[low67chevy]

looking good i have the same pedal setup got from a 88 square body style still putting them in my 56

[MTCK]

Progress has been slow with other life type things getting in the way. I finally got the old pedals out, new pedals and MC in, but ran into a snag when installing the slave bracket. Anybody else run into this? The threaded female portion of the bellhousing where the pivot ball threads in interferes with the advance adapter bracket. I think it would be easy to grind it down for clearance but haven't heard about anybody else needing to do that so it concerns me a bit. Pictures attached!

[Oilbrnr]

Seems to me that the AA adapter isn't correct. Wouldn't that boss be on any mechanical bellhousing?

[Oilbrnr]

BTW, how difficult was it to decide where to drill through the firewall?