Rehab of Patrol L60-2-00655

[r1lark]

Trip had to be postponed until later this week.

[r1lark]

Just got back from my Mom's. Got the Patrol running. I am so embarrassed -- it wasn't the condenser, or the point gap, or anything to do with the ignition system. It was out of gas!

Thought I had put more gas in the tank then that. Oh well, with gas in the tank it starts right up.

[v30crewcab]

"It ain't got no gas!" at least it was an easy fix!

[RiverPatrol]

You probably did put more gas in it, you've just forgotten how thirsty they are. Glad that it was something simple!

[faux40]

Thirsty is an understatement! I've been there too! With the whole family killing time waiting for gas on the side of the road! Glad the "fix" was easy

Just got back from my Mom's. Got the Patrol running. I am so embarrassed -- it wasn't the condenser, or the point gap, or anything to do with the ignition system. It was out of gas!

Thought I had put more gas in the tank then that. Oh well, with gas in the tank it starts right up.

[r1lark]

OK, back from our upstate NY vacation, grass is cut, weather is nice.........time to get the Patrol back out from its winter slumber. So, going to my Mom's tomorrow, get the Patrol uncovered and moved up to the carport work area.

Will get some measurements on the brake pedal/master cylinder push rod. Will measure the distance from the firewall to the end of the m/c push rod with the pedal in the normal 'at rest' position, and also with the pedal all the way down to the floor. From this (plus measurements on the original m'c and measurements on the Wilwood m/c) I can design the adapter to bolt the Wilwood dual master cylinder on. Even though I've re-read every post on this forum about adapting the Wilwood m/c to the Patrol, I can't find any info on how much the Wilwood m/c must be spaced away from the firewall to make the stock pushrod work. Thought I had read that there is 1" length needed on the adapter to make the stock unmodified push rod work, but can't find that anywhere now. No problem, with the measurements it can be calculated.

In reading the Wilwood info, the pedal/pushrod must be able to stroke the m/c to full stroke before the pedal goes to the floor. From the Wilwood tech data sheet: "The master cylinder push rod must bottom out in the bore before the pedal stops against the floorboard. The inherent safety feature of tandem master cylinders is the ability to still build pressure in one circuit if the other fails. In the event of a circuit failure, the push rod (and pedal) may travel 50% - 80% of the total stroke before starting to build pressure in the other circuit, allowing emergency braking to stop the vehicle."

The plan is to design and build the adapter at home, then take it to my Mom's and mount the adapter and m/c and test the stroke. More to follow..........

[r1lark]

Patrol started right up after sitting all winter and spring !

Got all my measurements. Wanted to get the brake pushrod off and bring it home, but the cotter pin in the pin fought me and fought me. Next time I'll bring my cotter pin puller. Boy, it's not easy getting up in the pedal area!

Pushrod stroke is exactly 1".............unfortunately, the full stroke of the Wilwood m/c is 1.10" so I need to figure out how to get an additional .100" stroke. The pedal hits the floorboard at full 'down' stroke so not much opportunity there (without cutting a slit out of the floor right under the brake pedal). There is an 'upper' stop for the clutch and brake pedals that holds the small rubber pedal bumpers; modifying this (maybe just some spacers under it - it's held on with two bolts) would probably do what I want. However, it would also raise (move them closer to the seat) the clutch and brake pedals somewhat which, given the fact there is already limited legroom for a 6'-3" guy, might not be the best thing.

Any other ideas on how to increase the pushrod stroke would be appreciated.

[RiverPatrol]

There is an adjustable push rod kit. I'm pretty sure that's what was used on Pinto Patrol. And a bit of spacing from the firewall when mounting the master. Adjustable pushrod kit

[Esteban]

The issue after the measurements can't be solved with any pushrod, since the pedal travel remains the same.

The Service Manual has the enclosed diagram that might help trying to figure out a solution. It's a highly detailed technical drawing of the pedals, travel, distance to the floor, and so for. According to that diagram, pushrod travel is 25.7mm or 1.01", almost exactly as the field measurement done by r1lark and shy by about 0.09" of the Wilwood travel (~3/32") Very little. If I was installing the Wilwood MC, I would do nothing to modify the travel and test the MC. Remember, the 1.1" from Wilwood will bottom the pistons all the way, that's it, if both circuits have failed. I'm sure that if only one fails, you will have much less travel of the pushrod and you'll be ok. Disclaimer to follow...

Brake Pedals Diagram.pdf

[r1lark]

Thanks Esteban for the drawing. I didn't realize that was in the manual.

Looking at the drawing you provided, the rubber bumpers p/n 46467-44000 are attached to a bracket held in by two bolts. If this bracket was moved 'up' (ie, away from the pedals) the stroke would be increased, but the pedals would move up and closer to the seat. Doing some quick math, based on the drawing's 180mm pedal travel, it looks like the pedal would come up towards the seat around .7 inch or a little less than 3/4 of an inch. With how tight the cockpit of the Patrol is for me, this 3/4" might make a big difference. I'll have to unbolt the 'bumper bracket' next trip, and temporarily clamp it on at the point where I have 1.10" of pushrod stroke, and see how the pedals feel.

I do agree with you Esteban that the full 1.10" stroke position on the Wilwood m/c would only be reached on a failure of both circuits. The Wilwood info says "In the event of a circuit failure, the push rod (and pedal) may travel 50% - 80% of the total stroke before starting to build pressure in the other circuit, allowing emergency braking to stop the vehicle." That means worst case the m/c would provide braking force to the intact circuit starting around .88 inch. But if I'm installing this dual chamber m/c instead of a single chamber m/c, the mechanical engineer in me keeps telling me to make sure the full stroke of the dual chamber m/c is available.

The Wilwood 260-7563 m/c just showed up. I'll get it opened up and see if both the front and rear chambers have the residual check valves installed, and report back later.

EDIT: there are residual check valves in both the front and rear port of the Wilwood 260-7563 m/c that I received: