[twilightcall]

Hi guys. I am a new owner of a 97 E350 Van with 7.3TD and 36K miles (orginal pump). I have read posts in the archives about loosing their brakes and almost wrecking because of a bad vacuum pump. Is there a way to tell when it is starting to fail? The reason I am asking is I live in a very hilly area and I don't want to lose my brakes completely especially if I am driving down the mountain as I don't think the E-brake could stop the car fast enough. Any info would be appreciated. Thanks.

 

[S95]

yup, brakes can go hard, or the bearing on the pully can fail( mine was bearing)

 

[twilightcall]

When the go hard will I have enough boost to stop or do I loose all my power brakes instantly. I just want to make sure I can stop safely without crashing.

 

[psu927]

You should be able to stop, I say this because when I unhook my vaccum from the booster, i still have brakes, jsut have to hit them really hard.

 

[pwrtrip]

I had my pump go out just the other day and the brakes go hard and you can still stop but you have to push the pedal really hard.

 

[twilightcall]

Thanks for the info guys. I appreciate it. I am glad that you can still stop. What mileage did your pump go out at?

 

[pwrtrip]

I have just over 200,000 miles and I am on my 4th pump. /ubbthreads/images/graemlins/vomit.gif I am thinkin of caring a spare with the pully and bolts on it already so just in case. There is no telling when they could go out.

 

[TCH777]

I think that depends on the truck. I could barely stop my truck even with the E brake to the floor. pushing my brake pedal did nothing even with both feet on it.

 

[twilightcall]

Really? That isn't good. Is it something I should just replace for safety sake or do you think it might fail even sooner with a reman from AZ or Adv? I just keep thinking about going down the S curves and loosing my brakes. I just can't let that happen as the only thing to hit are huge trees.
I have an E350 van that weighs more than the stock van. It is quite heavy. Its got 35K miles on the same pump but the pump is from 97 when the van was new.

Would an electric pump be worth the money in this case or am I worrying too much? I would have thought that the booster would hold a few pumps but I guess you wouldn't know the pump was bad until the brake pedal got hard.

TCH, how did you stop the truck?

 

[mchildress]

I lost one on my 83 6.9 at about 130,000 AC vent started acking up and brakes went the same day. Could still stop just needed more pedal preasure. My 95 bearing came apart at 140,000 but was able to limb home with out destroying the belt.Still made vacumn but the pully was about to fall off.

 

[TCH777]

clamped down on the e-brake and down shifted the auto to 2 and then 1.

My case could be worse case though. As the ABS light went on twice on the way home and then went out. So I did not think anything about it. But the next day the brakes had nothing and the pump was toast. YOu could hear the pump chattering as it ate itself up.

So maybe if the pump had gone completely that night I may have had enough in the booster to stop okay. Actually maybe I did and just didn't know it.

There are no electric pumps that really add enough vaccum that I have seen on this forum. If it is really that big of a concern some guys have converted their trucks to hydro-boost, where the booster is driven off of hydralic fluid from the powersteering pump. Do a search for hydro-boost if you want details.

Tim

 

[chris bottom]

i have had 3 fail on miune with no warning and each time i would notice the pump making more noise and it was spitting oil out of the top of the pump but one thing it will do at least with my experience is that you will get one good brake pedal push and if you let up on it the pedal will be rock hard and you have to stand on it to stop and thats what happened to me everytime mine went out.....gets your attention that for sure but i ran my truck all day city driving with a dead pump one day at a weight of 11k and just gave myself a little extra room and i was fine so dont freak out if you use common sense you will be fine /ubbthreads/images/graemlins/smokin.gif

 

[MarkEkberg]

With 215 K or so I found one on e-bay for $50 and changed it. When I took mine off I could see where the OEM seal was gone and you could see the bearings. Not sure how much longer it would have lasted.

 

[teamrope]

I know this is an old thread, but can anyone tell me how much vacuum I should see with a vacuum test guage? I'm getting 0 @ idle, just under 2 in at 2000 RPM @ the brake booster. Pump is producing 2 in @ the pump idle, 7 in @ 2000 rpm.

It's a 91 7.3 IDI with an ATS turbo if that makes a difference.

 

[Bill1013]

Around 13Hg to 17Hg. Sounds like your Vac pump is shot if all the Vac lines are not leaking. Check right at the pump, good there then, lines are leaking, brake booster could be bad also, plug off that big line then check.

 

[teamrope]

Thanks Bill.

She was only producing 2 @ idle strait off the pump, no other lines attached. The brake light has been flickering occasionally for a couple years at idle.