brake vacume pumps on diesels

[thehanko]

So the hilux brakes arent great... no suprise there. 1990 ln 106.

but I think they should be better, I have had my calipers rebuilt etc, I have the slightly larger calipers with the slotted disks.

I cannot lock up 31's at all in the dry and would struggle even in the wet.

(no i dont want to go around locking them up but it gives you an idea of their functional abilities).

I am considering going to an 80 series booster - dual diaphram to improve it.

But before I do, Im wondering if perhaps the vacume pump isnt making enough vacume... unlike a petrol engine where its garanteed could the vacume pumps wear out or wear enough so that they produce less vacuume and as such effect the brakes significantly?

Has anyone ever heard of this and how could it be tested?

or am i simply barking up the wrong tree with these thoughts...

[dans-paj92]

hey mate,
the vacuum pump runs off the alternator which has oil that is pumped through it which causes the vacuum.
My brakes I had in my old pajero was due to the vacuum pump needing a rebuild kit.
Is your alternator working good??
You can check the vacuum by disconnecting the vacuum hose off the power booster, if its not the vacuum pump then it is a hose or even the power brake booster.
P.S. I can't lock up my front brakes in the wet or dry, but that is with standard rotors, pads, and calipers and running 35inch rubber.
But I can lock up my back brakes no problem.
Cheers
Dan

[dans-paj92]

You could always try running a hose line from the power booster to the inlet manifold which is how the petrol motors get their vacuum.
Just block off the oil overflow hose off from the head.
I have heard that you can buy electric vacuum pumps for the brakes?
Im interested in this idea myself.
Cheers
Dan

[fletch89]

is your car lifted???if so have u extended your bius valve rod????

[Sic Lux]

You could always try running a hose line from the power booster to the inlet manifold which is how the petrol motors get their vacuum.
Just block off the oil overflow hose off from the head.
I have heard that you can buy electric vacuum pumps for the brakes?
Im interested in this idea myself.
Cheers
Dan

No way won't work the is no vacuum there as they don't have a throttle body so the air flows in freely hence why they need a vacuum pump go 80 series master don't worry about the booster. as for if the booster is working they have a warning light when the vacuum is geting low so you'll have a light on the dash if thats the case