Vacuum pump

[Shikaroka]

The vacuum pump on the 6.5 only operates the wastegate, right?
If I put on the manual boost controler, like this: http://www.heathdiesel.com/P/HDP1246/,
can I ditch the vacuum pump?

Has anyone just removed their vacuum pump and put on a shorter serpentine belt?

[MTTwister]

Others believe in letting the current system work. I believe that the 6.2 belt fits without the vacuum pump - Do a search through the threads - the actual belt to use is mentioned out there somewhere...

[Shikaroka]

Thanks.
I did some quick searching, but didn't find much useful information on the subject.

[Hubert]

Assuming you have a "F" in VIN or no EGR stuff. Spring "Turbo Master" is fine.

The debate rages on which is better. For sure the turbo master is simpler. The OE system does have programing to reduce boost at light throttle cruise and affords some protection to melt down. If you do the electronic boost fooler it also allows a little in cab boost control.

I am going with the turbo master soon. I am still torn at the benefit of dumping most all boost at cruise with light throttle.

I'll have to re read your signature. You have to have a boost gauge at least with the turbo master spring setup.

[Hubert]

By the way there should be several threads on it but its one of those subjects that a few key words will return most all threads.

[Shikaroka]

By the way there should be several threads on it but its one of those subjects that a few key words will return most all threads.

Yeh, that's part of the problem.

I have a temporary boost gauge hooked up right now, but I plan on putting in a permanent one soon.
Right now, my boost is very low. I am pretty sure the vacuum pump is bad and I'm not so sure the solenoid isn't bad as well.
So, instead of replace both those parts, ditching them is looking pretty good. I need a new belt too, so that is another plus. I doubt the vacuum pump adds much resistance, but the fewer the belt driven accessories, the better. I've heard of them locking up, so if I can do without it, I'd be happier.

I may look into making my owner controller instead of spending the $110 for a spring and bracket.

[Bnave95]

Use a belt for a 93 6.5 turbo.

[Robyn]

MHO
"Usually" if the waste gate solenoid goes south it will set a code but not always. What happens a lot is the Vacuum pump will start to go south and not produce enough vacuum or it will flutter badly. Mine did that with vacuum varying from 8-20 inches. The unit should hold a steady 26 inches at idle.
Do invest in a set of gauges so you can watch EGT and Boost pressure.
Once you take the control away from the computer you need to keep an eye on things.
Mind you I am no fan of the computers, but "mostof the time" they keep things working right.

[16gaSxS]

Did it about 60,000 miles ago and love it. Ditch that PIA vaccum system and save $$ in the long run.

[GMC Hauler]

it's either a 100 or 101" belt required.

The vacuum pump doesn't require much power to drive.

The vacuum pump can lock up causing you to loose your belt

There are a lot of advantages to going to a mechanical wastegate, and a few for staying with the vacuum system.

Pro's Mechanical:
Simpler system
Steadier boost
very cheap if you make it yourself (can be done for about $10)
reliable
typically lower EGT's

Cons mechanical:
Top limit on boost is not absolute. it will control boost over a range. Example: you set it around 12, but it will in actually control boost around 10-15 lbs.

Pros Electronic:
Keep factory system
With other mods, you could control boost from inside cab (you wouldn't make many adjustments)
Adjusts for altitude change
You should get better gas mileage with this style than mechancal (small amount)

Cons Electronic:
Wastegate will eventually blow open on higher boost (vacuum system cannot keep it shut)
Problematic


Personally, I believe the electronic system is better in some ways. It doesn't have constant boost on the engine at crusing speed while unloaded (when you need little to no boost), which can increase engine life by reducing stress on the engine.

I have had the mechaical system for a few years now and no problems.

I have thought about going back to the electronic system, because of better boost limiting, but i don't want the factory vacuum pump. I thought about using a vacuum pump from earlier models that goes on the distrubitor drive gear, but haven't made any progress yet. Another possibility is to somehow use a wastegate pod from another turbocharger, like a Dodge (they use intake pressure to open the wastegate) and interact this with the solenoid. Just an idea

[Shikaroka]

Thanks guys!

[rjwest]

I tryed the ' no vacuum pump ' thing

could not get an exact fit belt, either to tight
( had to loosen idler pully to get it on )
or to loose, gave up, went back to the
vacuum pump and installed a boost fooler.

still have a manual turbo spring kit, somewhers..