40 series general tech and classifieds

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Brake Master Cylinder....I've gotten two bad ones from CruiserCorps, OR something on my truck is killing them at install...

Any ideas? Do I need to change out the proportioning valve since I converted to discs on the back?

I'm thinking that I may need to adjust the plunger/rod depth vs the stock/OEM setup? Anybody have any experience here?
 
Brake Master Cylinder....I've gotten two bad ones from CruiserCorps, OR something on my truck is killing them at install...

Any ideas? Do I need to change out the proportioning valve since I converted to discs on the back?

I'm thinking that I may need to adjust the plunger/rod depth vs the stock/OEM setup? Anybody have any experience here?

I just got one from NAPA for my 77 and it works fine... I also have rear disc with no proportioning valve... When I swapped in rear disc had to take a small plastic thing (don't know what it's called) out of the master cylinder where the rear brake line comes out...

I'm sure I confused you more than helped you...

Scott
 
I just got one from NAPA for my 77 and it works fine... I also have rear disc with no proportioning valve... When I swapped in rear disc had to take a small plastic thing (don't know what it's called) out of the master cylinder where the rear brake line comes out...

I'm sure I confused you more than helped you...

Scott

Thx. That helps. Gonna give a third one a shot before I go oem.

Sent from my iPhone using IH8MUD
 
Rear reflectors...

Can't find anything specific on exactly where these go.

Thinking this is close enough. Anybody got a pic of their 40 that shows these?

Sent from my iPhone using IH8MUD

image-3578456330.webp


image-4232841036.webp
 
I've got a weird issue with the 40.

Finally got the brakes figured out, and was able to drive it for longer than a couple minutes.

After the engine warms up, I get a really low idle, almost to the point where it wants to die. And it DOES die every time that I brake.

I would assume this is a vacuum leak, right? But I can't find anything that's loose or missing??
 
Definitely a bad booster or a vacuum leak near it...

I can let the truck run for a minute, then shut it off, and when I press the brake pedal, hear a hissing as all the air leaves the booster.

New grommet, check valve, and hose on the way. Hoping spending $60 will save me the hassle of finding and installing another booster.
 
Chris put a mini truck booster on his I think. Maybe he will shed some light on the subject. Works fine.
 
Chris put a mini truck booster on his I think. Maybe he will shed some light on the subject. Works fine.

Me too. Works great even with front & rear discs.
 
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