Vacuum pump gone bad?

So I haven’t had power brakes for over a month just maybe one out of 8 stops
I’ll have a hint of it and I didn’t really care since a new vacuum pump is 170$

Until today when someone pulled out in-front of me and I couldn’t stop in time was in a parking lot so 10 mph let’s just say 7k pounds of American steel won against that small sedan and it’s likely totaled but all it did was break my bull horns

Anyways I’m getting 6.5-7 in/hg of vac at the brake booster I feel like that’s low can anyone back this up?

Parking lot should be “no fault” I hope!!!

Does your brake light illuminate on low vacuum? Mine does.

If no one confirms your reading, I can in a couple days. Honestly that seems low and should be 18-20 at idle.

Does your HVAC system get stuck on Def/Flr? I think that’s default.

Cant Write said:

Parking lot should be “no fault” I hope!!!

Does your brake light illuminate on low vacuum? Mine does.

If no one confirms your reading, I can in a couple days. Honestly that seems low and should be 18-20 at idle.

Does your HVAC system get stuck on Def/Flr? I think that’s default.

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It’s permanently on vent it has never switched to floor or defrost in the 2 years I’ve had it, no brake light

How does the windshield defrost in the winter....?

Do you carry a torch?

Cant Write said:

How does the windshield defrost in the winter....?

Do you carry a torch?

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I park under cover so never had to deal with ice, when it gets really foggy I crack the window
Also rain x works wonders

Correct, you should have 20+ inches of vacuum. 6 or 7, either your pump is bad, or you have a huge leak somewhere. Stuck on vent is odd… becaus no vacuum is normally defrost only, since seeing is more important that the other settings. I wonder if someone rigged it to stay on vent for some reason. But yes, I would look at the vacuum pump, and the system. Check all your hoses… if you have a Hi-C can, make sure it’s not rusted out.

The brake light not coming on for no vacuum doesn’t surprise me…. We had one that had a “lazy” pump that took a bit to pump up, and it never turned the light on….

I agree, should be at least 20.
I just went through this last summer.
Checking through things, narrowed it down the VP.
replaced it, and seemed to help. But vacuum seemed to be sporatic. Drove around with the HF Vac gauge in the cab to see what was happening while driving.
I would have Brake application on the first use, then almost nothing on the next coming to a stop.

One thing I did notice, pushing down on the peddle, got a whoosh of a vacuum leak under the dash...guy at NAPA said it was normal. Didn`t think so.

Finally replaced the Booster I bought at O`Really`s, and best brakes it had in 8 years.
And no whoosh under the dash.

On the passenger side inner fender is a black round plastic ball with a vac, line, and another 3" round 1 1/2" thick dohickie with a vac line and electric plug. That I think is to make the dash light work when you loose Vacuum.
Mine did not work and went bubuy into the trash.

I don`t have a Tach., so installed a Stewart Warner Vac. Gauge in place of it. Will need to remove Inst. Cluster and do a bit of fab work.
Not a big deal.


Goat

My “lazy” to pump up VP does light my brake light. I chalk that up to a win!!

Replaced it with a new napa pump hopefully I get better luck than I hear about the pumps part quality

I painted my pully and bracket and put them outside since it was warm and sunny 2 hour nap later it was raining… oh well

Power brakes still aren’t very good I guess booster is next but atleast I’m getting good vacuum once again

Do you hear the “whoosh” sound when stepping on the pedal that Old Goat mentioned above?

Cant Write said:

Do you hear the “whoosh” sound when stepping on the pedal that Old Goat mentioned above?

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Slightly,

I just took my van out for a warm up drive as I’m going to check on my ujoints. I got the swoosh sound as well.

@Old Goat does the swoosh sound always mean bad booster, or could it be the line to the booster as well?

Daughter home sick from school, man she has been sick every other week ever since they took the masks off. Thanks sociology experiment. Gonna play with her first.

Iam no expert on Brake Boosters, but that was my experience, changed it and best brakes I have ever had.

I do not get the swoosh any more.
The Line to the Booster is the vacuum line going to the Vac Pump. So it is a suction line pulling out the atmospheric pressure in the Booster, creating a super low pressure.
So when I applied the Peddle and got the swoosh, it must be a seal that is worn or compromised that was letting atmospheric pressure to rush in.

So the Vac. Pump is really a suction Pump, best way to describe it....and the whole system needs to be tight.
These so called re-built Boosters are a krap shoot at best.
The guy at NAPA saying it was normal to have the swoosh,,,ahh I didn`t think so, and now don`t have it and work perfect.
The SW Gauge I mentioned above, I think it is more important than the Tach that is suppose to go in that space.
The next best thing is to do the Hydroboost set up.

Sorry to hear about your daughter being so sick.
She is more important than our old trucks.

Have you ever heard about Elderberry Syrup? It is to help the immune system. We take it when we have been around or going to be around a lot of people....Like Costco etc... or we feel like something is trying to get us.
Does it work? Don`t know, but we have dodged the Covid thing, don`t wear a Mask, only when some store made us. Iam 79 and married to a sweet young thing...
We get it from Vita Cost, brand is Nature`s Way, Original in 8oz bottles. pricey but worth it.
Usually order 10 ata time to always have them on the shelf.

Take care...Goat

@Old Goat Thanks!! Will look into the syrup.

Thanks for the lesson on the vacuum system, more than I knew.

If you can handle it, garlic is one of the best natural immune boosters. Also is said to have a lot of antibiotic properties.

James