vacuum pump QUESTIONS

DOES A VACUUM PUMP RUN ALL THE TIME

HOW MANY INCHES DO THEY MAKE

ANY RECOMMENDATIONS WHICH ONE TO USE

Maximum inch needed to use frame mount power brakes booster -automatic C-4 trans--

any pictures would be great-- Thanks

 

I used to have a few off Ford diesel trucks I took off when dual alternators were added ( years ago ). They were belt driven and ran when the engine did, they would pull 15-16 inches if I remember right.
https://i.ebayimg.com/images/g/yIgAAOSwPcVVw62m/s-l960.jpg

 

I just installed a pump from Leed Brakes on a customers car.
Very quiet rotary style pump.
Very simple install.
Automatically starts when vacuum is lower than 15 and shuts off at 25.

I would stay away from the lower cost piston type pumps as they are very noisy, they will shake the rust off the car.

Bill

 

To cure a low vacuum issue on a customers cammed up small block powered pickup,I used a vacuum pump off of a late model Camaro, along with a vac reservoir tank. I installed a vacuum switch from summit into one of the ports on the reservoir that closed when the vacuum dropped to 15 inches as stated above and then opened at 25 inches. I had the pump running off a relay and the vac switch just completed the ground side of the relay. It was a very quiet pump you could barely hear run. The power brakes then worked flawlessly.

 

As Joe H said, the early diesel pickups have an engine driven vacuum pump. It was needed because the HVAC system and primaily for brake booster were same as gas trucls that had readily available vacuum. Diesels don't run any engine vacuum, so the external pump is required.

I have an 88 F-250 diesel truck; 7.3 IDI is the engine. Pre-Powerstroke, it's mechanical injected. The vacuum pump has no noise, at least compared to the rattling diesel engine. Never measured the vacuum level.

 

Try and use an Alternator off a Japanese Diesel
They have a vacuum pump on the back of them for the brakes.




Perfect cure for vacuum wipers

 

I installed a LEED brakes vac pump-- works GREAT , power brakes work great
I found out the timing distributor was 1 tooth off could not time move it enough to time it
set-up carb adjusters is OK but should have more air-- 500% better then I got it --the engine only has 174 miles on it
so got to decide if I want to keep it or change

 

Did not like the POWER and all the ROCKING & ROLLING of the engine--Pulled it out and going to put my Ford 351 W- HO in -- nice smooth, great sound and more then enough power

 

BTT

 

Vac pump from a ~98 GM 6.5 diesel will get you ~ 20" at idle & ~ 25" above that. Very little noise, (flat/multi-rib)belt driven, mounted on block front, low under alt. It may be(probably is) rpm sensitive, so just gear correctly via different pulley.
Marcus...