Powermaster issues

[Scoobum]

Earl, how tough is it to ship to Canada these days.

[IL KIM]

Thanks Earl. I found your store and see you have some nice stuff including 1 remaining vacuum booster conversion kit. I will order both the lines and conversion kit please.

[earlbrown]

Scoob. It's not that bad, it's just expensive as hell.   For some reason I have to fill out the individual weights on the custom form for every single piece in the box.    ....and it has to add up to the shipping weight.  So according to the gobment, I have to use weightless boxes and packing suplies.

For example, an $8 small flat rate box can go to Guam, Hawaii, Puerto Rico, or the virgin islands and weight 70#s.

That same box going to Canadia can only weigh 4#s and it's $22.       What's really bad is I can send that same box to Australia for the same money.

[daveismissing]

Earl sent me some things - he made it seem painless ( I'm sure it wasn't)

[IL KIM]

Received parts. Thanks for the fast shipment Earl. Now I have to git er done.

[earlbrown]

Now the fun begins....


....god, I hate bleeding brakes!

[Scoobum]

The one over the rear axle can be a whore to change. Bleeding brakes is a piece of cake. Don't know why people have a coronary about it.

[earlbrown]

I probably got spoiled from doing motorcycles all those years.   There's not much in life I like more than having to buy a new caliper when ''I'm almost done'' because of a seized (then broken) bleed nipple.



Plus, I spend HOURS trying to put my nascar pads in my nascar calipers on my nascar spindles, just to learn that I'm still a few hours away.



...just to learn that my rear nascar calipers won't go over my rear nascar brake rotors and there's a gap between my nascar axle flange and my nascar caliper.....


Moral of the story: I thought all those POS's were the same, and Ihate bleeding brakes! 

[Recklessrob]

I'm still running a PM. Just fixed one for a customer this week.

If you whacked the motor and it kicked on, its likely a motor, but the switch failures are more common.
Check to see what color switch you have. You should have a grey one. If its black you should replace
it, as those were recalled years ago and most but not all were replaced.

[IL KIM]

My motor is intermittent; sometimes the pump doesn’t suck the fluid down.  I have the grey pressure switch so it ok. I think the wiring in the PM is acting up. Thanks though.

It’s a warm day into the 50’s here in Michigan so I finally started the conversion. I have the brake pedal out and not sure where to drill the new hole the the pin. 1-1/4” down but far from the edge of the Pedal and which edge?  I can’t see any pics from the TurboBuick site to go with the directions.  Anyone know or I’ll wait on pm sent to Earl...

I have the new booster installed and can work on bench bleeding the master cylinder For now.

Cheers and hope everyone had a great Thanksgiving given this pandemic.

[Steve Wood]

https://gm-efi.com/news/brake-pedal-conversion-kit/ see the picture at the bottom showing where to drill the hole.

Some discussions show 1.25" -1.50"  http://assets.superchevy.com/f/9435672.jpg?

[IL KIM]

Thanks Steve. Great stuff from a software/electrical guru. Between this and recommendation from Earl’s PM to preinstall the pedal to verify hole location I think I will be good. Will report out afterwards. Love the knowledge this community has.

Interesting pics - the Pedal in GBody pic slightly different then my 85 GN pedal.

Did you mean to add article links on 1.25 to 1.5” distance or just show the jpg attached?  I’d like to maintain pedal height if vacuum booster travel allows relative to Powermaster travel.

Thanks again.

[Steve Wood]

I normally suggest 1.5".  But, when googling, I found distances of anywhere from 1.125 to 2.00".  2.00" is what some guy used to get a 7 to 1 leverage ratio which he thought was ideal based on his reading of some articles on master cylinders.  The larger the offset toward to the pivot point, the greater leverage multiplication one obtains and the less pressure required by the foot on the pedal.  I don't think it is required by my own experience with vacuum brakes but that is what is great about google.  If you don't like the answer you get, try another link.  Google offers no warranty on it's offerings.

If you do your own googling, you will find that vacuum brakes are often around 4-1 while manual brakes are more like 6-1....

I'm sticking with 1.5" on the hole move or whatever Earl's theory of the day might be...it's not sensitive.

[earlbrown]

My theory of the day is to pull the pedal against the brake light switch and use the exact booster in the exact car to scribe/mark the exact pedal arm.


That way the brake pedal is still in the same spot where your foot expects it to be.

[ULYCYC]

Do what Earl said.  If its off a hair it doesn't matter like fitting cove base moldings. That's the way we did things before the internet gurus gave everyone headaches.