Vacuum pump change out

[David Brady]

My pump is bad and I got a new one but my book says to pull off the pulley using the special tool and put the pulley back on using the other special tool. Is this necessary or can I use standard pullers and a press?

[rjschoolcraft]

You can use standard pullers, but it is risky. It is very easy to break the lip off of the pulley. I bought a pulley puller and installer tool from Carquest. It wasn't too expensive, seems like around $50, IIRC. This kit works on the PS pump pulley as well...I've used mine a lot.

[rustypig]

If you don't want to buy the puller kit you can check with Autozone or Kragens etc...if you've got one near by you. They usually have a free tool loan program where they put a deposit on your credit card, but if you bring the tool back in good condition they don't charge you. And yes I agree with above...using the correct puller is much faster and doesn't run the risks of breaking the pulley etc.

[schamp]

Hi, I just replaced mine. I used a standard puller. One that grabs on the lip of the pulley. I used a prophane torch to heat up the pulley (not red hot) then eased the pulley off. Mine came off with no problems. Then with the pulley still hot put it on the new pump. Try and remember how far the pulley was seated on the old pump so you know how far to put it on the new one. Before you start heating up the pulley find a bolt that will screw into the center hole to put the pulley on to the new pump. I removed my alternator to give me more room to get the old one off. Disconect battery before you remove the alternator, as it is easy to short out the connection at the alternator. There is a small do nothing clamp on the vacume hose at the pump. I removed mine with my hands. Check the hose to make sure it is not cracked, etc. There have been some comments about putting some oil in the pump but my new one did not come with any instructions about this and I did not see anywhere to put some in. Your truck will run much better with a new pump and you might as well replace the wastegate silenoid while your at it.
Mine had a metal fan guard on the new pump which was not on the old one. It does not get in the way when putting the belt back on. I left mine on. Good luck. Spence

[Kennedy]

I've found it simpler to offer the pump with a new pulley installed. This eliminates the potential of having a down truck with a broken pulley and can make life much easier...

[Robert Shupe]

Get yourself a turbomaster adjustable mechanical boost control from Heath Diesel and get rid of your vacuum pump. Then run a serpentine belt from a 92/93. YOU WILL LOVE IT!

[rjschoolcraft]

Don't go the turbo master route on an electronic truck. I know people are doing it, but you lose the altitude compensation that the computer can give you. For those who've done it, I am glad that you like it and I hope that you are still pleased years later. Besides, it's easy to change the pump (I've changed mine) and it's easy to change the pulley with a $50 tool that you can use over and over again. With the right chip and/or an electronic boost control, you get everything the turbo master gives you plus the altitude compensation.

My opinion.

[David Brady]

Thanks for the information. I have chosen to eliminate the vacuum pump, thinking that simpler is better. The altitude compensation gave me some pause, but I think eliminating hoses and pump will be easier in the long run. I'll let you know how it runs with the turbo master and chip in.

[whatnot]

What are you going to do about the EGR system? With no vacuum to it it will keep the SES light on.

[Robert Shupe]

Engines with an "S" code in the VIN # will have EGR however an "F" code engine will not have EGR. In either instance the Heath Max-E-Tork chip will fix the SES light problem.

[Robert Shupe]

JDave, If infact your engine has EGR, vacuum is required for its operation. However the 6.5 will run just fine with it disabled. As for the SES light concern I believe the chip will correct this. Altitude compensation is not a valid concern as the T/M controlled turbo provides greater performance over that of the factory setup. A drive in the mountains will speak for itself concerning this issue. Bottom line is you should direct any further questions to Mr Bill Heath of Heath Diesel, he is a super nice guy and he knows his stuff inside and out.

[rjschoolcraft]

Yes, it is a valid concern. I look forward to that drive in the mountains and report back. The Turbo Master is nothing more than an adjustable exhaust back pressure regulator...once back pressure is high enough to over come the spring force, the waste gate opens, that's it. Besides, a good chip will cause the vacuum actuated waste gate to stay closed and give similar levels of boost as the Turbo Master on an electronic truck. I am all for the TM on the mechanical trucks because it gives you adjustability that you didn't have before. It increases the control you have over your engine. It is a Band-Aid on the electronic trucks, though, that reduces the control that you have over your engine.

My opinion.

[David Brady]

I wanted to let you guys know I've installed the turbo master and the max-e-tork chip from Heath diesel, the installation went great and I'm very happy with the results. I'll let you know on the mileage after a few weeks. I can recommend Bill as very helpful, even when I called late because I didn't know what I was doing. I just need to get my EGT with the extra boost. Thanks all for your input.

[britannic]

You don't need to worry too much about the altitude compensation modulating boost; if your base boost is set high enough there will be enough air to burn the fuel.

My 6.2L happily runs up to 15psi boost and has no problems whatsoever at elevations of 8500' plus - I love blowing by all of the gassers who're bogged down and running too rich up there.

[Kennedy]

A properly set up chip should not need a mechanical wastegate control.

A mechanical wastegate control i s merely a back psi regulator. Whack the throttle and back psi spikes and gets the turbo rolling. Clip the spike and the response is lessened.

Different engine loads and exhaust temps (you know heat has a great affect on these things) will vary the amount of boost delivered at a given back psi. As rpm goes up, it is often necessary for pressure ratios to get out of line to get enough air to keep things cool.


Good example: My Dmax can run 18-20 psi at max RPM stock with a nearly equal back psi.

It can also run 24 psi boost with 18 psi in the exhaust at 1800 RPM with the proper fueling.

If mechanical springs were the magic key, why don't Holset, Garrett etc take the pressure diaphragm out of their wastegate cans and use simple back psi???

Ronniejoe saw first hand the effects that increased wastegate solenoid duty cycle (read as hold in psi) has on responsiveness...

[David Brady]

JK,
I'm not a Mechanical Engineer, and I understand that GM had to make some compromises when they built the 6.5TD. My problem is with the $250 vacuum pump that wears out and the rubber lines that will soon need replacing as well. If I can replace this system with solid parts that work and seem to work very well, I'm happy. I just think of all the bigger T.D.s that don't have any waste gates and how they don't have this maintenance problem. Would a different exhaust housing or a lower RPM limit make the difference with this system? I'm used to wastegates used to limit boost for parts longevity not to let extra CFM by the turbo. I'm looking to learn, please point me in the right direction. smile.gif

[Kollin Syverson]

Just installed my Turbo-Master last night. What a world of difference. I do have a high performance chip in already, but boost would fluctuate between 9 and 14 PSI on hard pull. With Turbo-Master, it will not drop off or fluctuate, its steady as a rock. ( get it, like a ROCK) tongue.gif :D

[StephenA]

This is an extremely informative thread. My 92 has an ATS waste gate braket, which uses the stock actuator. Since I have no chips, the Turbo-Master should at least give me adjustability, right? Does installing the T-M altogether defeat the vacuum control of the waste gate actuator in mechanical IPs appilications?

[whatnot]

Originally posted by StephenA:
the Turbo-Master should at least give me adjustability, right? Does installing the T-M altogether defeat the vacuum control of the waste gate actuator in mechanical IPs appilications? They didn't start using the vacuum operated wastegates till 94.

[Turbine Doc]

As far as throwing codes on a L56 EGR engine, run a L65 PCM that does not look for the vacuum or EGR inputs. Go to the boneyard get a 99+ PCM F (L65) not only will you eliminate emissions stuff, but you will get the HO 76mm fuel program in the later series trucks.

[StephenA]

Thanks Phillip- so I may not even have a vacuum pump, & the hose going to the top of the turbo must be oil? This truck gets simpler everytime I look at it.

[Uncle Wally]

<Laughing>

Why not just run a non-wastegated turbo from Peninsular Diesel and get a chip from Kennedy that hides the boost signal. No more vacuum pump requirements! Lot's more power!

Oh - I already did that!

[britannic]

Originally posted by Uncle Wally:
<Laughing>

Why not just run a non-wastegated turbo from Peninsular Diesel and get a chip from Kennedy that hides the boost signal. No more vacuum pump requirements! Lot's more power!

Oh - I already did that! YMMV: Non-wastegated turbos are great, but be prepared for more boost lag low down in the rev range. If you're into long distance freeway, enjoy the power, but off the line the behavior quite different.