mechanical IP conversion

[mobilevet]

I saw the article on the mechanical IP conversion for the '96 6.5 on the Diesel Page site.

Will the same conversion work for a '94 6.5?

thanks

[DmaxMaverick]

Yes. It should be easier for a 94, compared to the 96. Your ECM is OBD-I (less control/monitoring). Get your hands on a 93 or late 92 ECM and it should be a snap, especially with your 4L80E.

Essentially, you'd be making a 93 powertrain out of it.

[mobilevet]

That's encouraging. I just bought this thing and now it is "missing" at high speeds - only occasionally (10 times on a 300 mile trip) but the last time it did it it was a pretty hard jolt and the SES light came on.... and no, I have not yet done all the diagnostics to be sure it is the IP, but my mechanic thinks it is (yes I know that they tend to jump to that conclusion) and if I'm going to have to put a new one on, I think I'd rather consider increasing the reliability by going to the mechanical pump.... I really need this thing to be trustworthy because I'm going to use it for my veterinary truck and sometimes I'm out in the boonies at all hours.

From the article it looks like the pump is the Stanadyne DB2-4911 - that right? How expensive is this pump? New or Rebuilt?

The article didn't say much about the install - is it a simple remove the old IP and bolt on the new one deal?

Other than that, the additional mods look rather self-explanatory.

[mobilevet]

Forgot to ask, what about fuel mileage? Same, better, worse than the electric IP??

[More Power]

From the article it looks like the pump is the Stanadyne DB2-4911 - that right? How expensive is this pump? New or Rebuilt?

The article didn't say much about the install - is it a simple remove the old IP and bolt on the new one deal?


Yes, a DB2-4911 would be the best choice, and you can keep the stock injectors you have now. You will need the matching 1992-93 fuel injector lines because the DB & DS use different fuel line fittings.

The 4911 prices are all over the map. A quality rebuilt 4911 could cost something on the order of $500-$750. I'm sure you'll find one for less on eBay or some other discount shop. Just be sure you get a genuine 4911 and that it is from a reputable shop.

The pump installation is just like any other 1992-93 install, that's why it wasn't discussed in the article. It's easy for someone who has done it before. For those who haven't, it is thoroughly covered in the 6.2/6.5 Diesel Troubleshooting & Repair Guide (see link below) - and I'm sure you could find help here in this forum using the search function.

Fuel economy.... It's likely there won't be a lot of change, or it could improve if the new parts are delivering fuel better than the old parts were.

Just remember that maintaining 4L80-E transmission control is the biggest hurdle to cross when converting. I recommend a programmable aftermarket TCM and wiring harness because you won't have as big a problem with the wiring connections as you might when using a OE takeout system. Just my opinion...
www.powertraincontrolsolutions.com (http://www.powertraincontrolsolutions.com)

Jim Bigley

[xtrempickup]

Is the swap a better solution to replacing PMDs and screwing around chasing IP problems as they occur. i have a 95 and thought about it and was figuring the mechanical pump would also make it easier to convert for Biodiesel

[DmaxMaverick]

I mentioned, but didn't go into any detail, but I think you can use a 92-93 6.5L TD ECM for tranny control. It should plug right in, and will be much less expensive than a stand alone TCM (get one out of a wreck). It will also be more friendly with your new "now less sensored" powertrain. The boost control will be mechanical, as well, so the 'puter won't miss that, either.

[xtrempickup]

this sounds like the route to go should my IP fail anytime in the near future

[3legdog]

I have a '94 GMC I was thinking of converting to mechanical IP, and I had the same idea to use a '93 ECM so the 4L80E would still shift, but I looked at wiring diagrams for both years, and the pinout is different. So you'd probably have some rewiring (and possible harness replacing) if you went that route. That's what's keeping me from doing it. My trucks currently not running because of an IP failure, that's why I looked into it.

[More Power]

I have a '94 GMC I was thinking of converting to mechanical IP, and I had the same idea to use a '93 ECM so the 4L80E would still shift, but I looked at wiring diagrams for both years, and the pinout is different. So you'd probably have some rewiring (and possible harness replacing) if you went that route. That's what's keeping me from doing it. My trucks currently not running because of an IP failure, that's why I looked into it.

That's why I recommend an aftermarket TCM..... With an aftermarket TCM & harness, you connect ign power, ground, engine speed sensor, throttle position sensor, and snap the harness connectors onto your transmssion. I've done it with a Jet Performance 4L80-E TCM/harness kit. It's easy. :) Please note: Powertraincontrolsolutions.com is not a supporting vendor, but I recommend their products mostly because of the shift control programming can be updated using a laptop. The Jet kit worked well, but it used an OEM TCM with a programmable chip that an owner can't easily modify. Most TCM products out there are made for the gas market, and the diesel requires different shift calibrations. I needed to send the Jet chip back & forth a few times to get it to shift the way I wanted it to. Jet was good to work with, but I'd like to be able to tinker with the programming to get everything "just right". The PCS TCM will come with a "basic" 4L80-E program that can be adjusted by the end-user. ;)

As far as I know you can't just unplug the 1994-99 PCM and plug in the 1993 TCM. There's no provision for ESS & TPS, and I doubt the pinouts are anywhere near the same (I haven't checked, but I'd be really surprised if they were even close).

Jim

[xtrempickup]

Boooo that stinks. back to dealing with stocker

[mobilevet]

What's an aftermarket TCM cost?

Does the 94 need the thermostat housing reconstruction? What about putting in the dual crossover and high flow pump?

[DmaxMaverick]

The stand-alone TCM's I've priced were $500+. Been a while since I've looked, though. A used ECM, some wiring, and your time should be less than $100. The TCM would be the most "convenient", but if you are using your original ECM, you will still have to deal with it complaining about the now missing sensor inputs. An easy solution would be to pull the SES bulb and let it complain. The reason I suggest using a 93 ECM is user-friendlyness, continuity and diagnostics. If it is controlling the tranny, it will also flag problems with it and throw DTC's when something is wrong. There wasn't much interaction with the 93 ECM, but there was enough to keep you from frying the tranny if, say, you have a pressure drop or excessive slippage. It won't engage limp mode, but will at least turn on the SES.

The upgraded cooling system is always a good idea. If you're in there, might as well knock that out. I wouldn't call it "reconstruction", though. Maybe some modification to get it all to fit, but not reconstruction. The high flow pump is also a beneficial addition.

[More Power]

The PCS system was about $800 the last time I checked. There are several companies selling 4L80-E TCM/harness kits. I seem to recall GM Performance Parts had one, and there are others. The only programmable TCM/harness/software kit I've seen personally (shot some photos & looked at the software on the PC) was the PCS version.

Jim

[mobilevet]

Very interesting.... now to be sure I actually have a pump problem or an electrical one. The problem is a "miss" at high speeds that gives a SES code 18, which is related to the pump cam position (I think - don't have my TDP R&R guide with me).... Heath Diesel suggests that this could be due to a bad resisstor in the wiring harness (which they sell a replacement part for - $60)... very tempting to get the wiring harness before spending $1000 for a new pump or a conversion...any thoughts?

Also, how do the mechanical pumps compare with the electrical as far as longevity... my mechanic says 80-100k (average) for the electrical - 150k (average) for the mechanical... I assume they are better and worth the trouble of the conversion....

Also, this truck has 3 PMDs under the hood - one on the pump that is bad (per two owners ago), the replacement for it on the fire wall and another plugged up that was supposedly bought as a "backup" for the one on the firewall - but is currently plugged up. Makes me wonder if the pump was giving problems and the third PMD was installed as a "quick fix"...

[More Power]

The lack of a filter harness Heath mentioned could be the cause of what you're seeing for a miss/skip. That is one of several possibilities.

DTC 18 - Pump Cam Reference Pulse Error

It could be due to the insulation being worn on Optical Encoder Sensor harness, or the main injection system harness. Could be due to a pin contact issue in the main harness connector (near the firewall above/behind the engine). It could also be because of an intermittent OES.

Mechanical injection pumps can run normally for 100-300K miles. A lot depends... The marine DB2 we used in our 6.5 Project ran more than 250K before the truck found a new home in CA. The DS pump is equipped with ceramic rollers on its pumping plungers. This likely helps, but the rest of mechanical components inside the pump are subject to the same sort of wear as a mechanical pump. The reliability of the DS electronics is the issue....

Stanadyne has long held that the PCM can contribute to some DS failures, and there have been dealers that wouldn't honor the DS extended warranty unless the owner agreed to a PCM replacement. Me.... I think it's not likely....

However, anything that causes the FSD/PMD to work harder can shorten its life. This could include a dead fuel lift pump, plugged fuel filter, possibly a dragging fuel solenoid inside the DS, and probably others...

Jim

[mobilevet]

Sound like I need to pull that section of wiring harness and give it a good look see....

Also, my understanding is that if you upgrade to higher flow water pump you'll need the crossover housing with the dual t'stats:

1.) Will a crossover from another year model (which one?) work on the 94? If so, any problem getting one off a wreck?

2.) What about going to the dual t'stats? From the picture in the MFI conversion article it looks like they both have cables coming from them... what are these are where do they go (since initially there would have been only one t'stat)??

thanks

[mobilevet]

Never mind (#2)... I just read the article on the cruise control adaption... looks like what I was seeing were the cables (throttle and cruise) coming into the throttle bracket.

I would however like to see how to make the throttle bracket.

[93GMCSierra]

From my understanding the change in throttle and or cruise brackets is required on the 93, and earlier, mechanical linkage, but the 94 and up used electronic control so there is no fabricating to do.
Also if my understanding is correct the dual t-stats and high volume waterpump work together to do alot better job so you will need that, 97 and up all would have that, early 96's were single, later 96's changed over.

[mobilevet]

So it sounds like a crossover from a 97 salvage with some new t'stats should work...

Re: bracket - yeah, your right about the pumps... I asked about the bracket because I'm looking into the conversion to the MFI. - thanks though.

However, this is a good time to inquire as to a good place to get those high flow 180 degree Robertshaw t'stats?

[mobilevet]

Well… as far as the mechanical IP goes, looks like a rebuilt one will cost around $1000. $699 for the pump and a $300 core since I won’t have a 4911 to send back as a core. However, I may have located a 4911 off a wreck. I don’t know the miles on it yet, but for around $300 I wonder if it would be worth trying? Worst case, it goes kerplunk and then I buy the $699, but don’t have to pay the core since I can send in the salvage 4911.

Anyway, got a few other questions:

Air snorkel – I was going to remove that, but 1) how do I get it out of the quarter panel? and 2) what do I do with the big hole on the side of the air box – leave it open as is? Put a screen on the big hole? Replace the air box with some other aftermarket version?

Where can I see some good pictures (line drawing diagrams would be better) of the engine compartment? This truck has been so rigged up that it’s got stuff going all over the place and I’m sure that most of it is in the wrong location. It looks like it has replacement aftermarket ground cables – is the interconnector ground cable supposed to go over the fan shroud from one side to the other??? The little brass valve the allows you to drain the fuel filter is zip tied to the bracket – surely this was connected a bit more securely originally???

Lastly, back to the MIP conversion, what about the computer problem? That is the biggest hang up for me. I don’t really want to foot the bill for the aftermarket computer (I don’t see myself desiring to mess with it much), but I’m not comfortable jumping into this project without knowing exactly how to get the computer set up and the transmission shifting properly. Any ideas/help is appreciated.

Thanks.

[DickWells]

:)I did my 95 Suburban 3 years ago. I had done all the other (usual) stuff. IC, remote FSD, adjustable boost, Phazer gears, etc, etc. Still had issues with engine dropping out at odd intervals.
Post Mech. IP, I went 30K miles without a skip. Towing!
For me, the transmission thing was not a show stopper. But. I had to design my own throttle cable to throttle position sensor, and then learn to live with a couple of quirks that I don't think everyone would want to live with. That's why More Power is probably right in recommending that you go with the stand-alone trans control. BTW, it listed for about $650 for the computer, plus another $150 for the cables! The outfit is down in PA somewhere, and you will find them listed somewhere in the DP archives, or someone with a better memory will jump in here with the name for sure.
The issues? Well, for starters, the old Burb will refuse to shift out of first every once in a while. Just throw it into neutral, shut off the engine, start it back up, and you're all set for a while. If you're running it a lot, it seems to act up a lot less. Our first trip (towing) cross-country, we went from Vt to WI before it did it the first time. After a couple of times that day, not a hitch for another couple of thousand. Around home this Christmas, it did it 3-4 times a day for the first few days, then got progressivelly better. I'm a stick shift guy at heart anyway, so the fact that you need to lift your right foot between some shifts for best shift quality is a natural. If you don't like these two issues, bite the bullet and go for the trans computer.
I still have the original boost control (electronic) and it works fine. But, I also DON'T have a vacuum solenoid hooked up. I cut that out of the equasion years before I went with MFI. Never missed it. Don't know how you'd automatically get mechanical boost control by just swapping IPs, but the previous post says so, so maybe the more experienced guys know something.
You'll never get a quicker starting, better running 6.5 than when you put a well built 4911 pump in. The Burb always used more fuel at idle with MFI, but got better milleage on the road, especially towing. I gained somwhere around 1-2 mpg.
The brand new pump cost me $1200.
The mechanical lines are a different diameter. The caps at the pump are smaller, but are the same at the injecters. Best bet is to get a pump with the lines all on it, as I did. If not, addapters are available.
There are several other issues to solve, but they're minor.
Just one electrical line instead of half a million to worry about. I never did hook up the fast idle wire. Didn't need it.
Lots of white smoke on cold start up, and some shaking, but it smoothes right out and runs REALLY nice. Could I risk a little more advance and elliminate some white smoke? GMCTD? Anyone? Anyway, the old Suburban puts a big smile on my face whenever I get back home and get a chance to drive it.
Good luck to anyone who goes for the MIP route. For me, I wouldn't have it any other way.
Dick Wells:)

[914turboford]

I read in this thread that the 4911 is the pump of choice for a MIP. What was the OE application(s) for the 4911? I have a 6.2 IP laying around. Would that be suitable for my 94 Burb? Will it even bolt on? It was from a Banks turbo'd 6.2, FWIW.
Brian

[Robyn]

The DS4 uses a higher injection pressure than the DB2
The 6.2 IP off a "J" engine will work if it is turned up to meet the fuel needs of the 6.5 TD. Use the early 6.5 mechanical engine injectors or have yours reset to 92-93 6.5 specs.

The DB2 was not designed to opperate at the higher DS4 pressures

***Dick***
As far as white smoke on startup be sure you have the Cold advance hooked up. The fast idle is not a biggy but the cold advance setup when working right will stop all that smoke at startup (Should)

What are you using for a TPS. I have seen a few setups where the original PPS was modified to accept a throttle cable (The Mickey Mouse) :D and it was not perfect but worked to the point of being acceptable.

The last one I saw had a little crank assembly fabricated to attach to the throttle cable. The factory (92 93) 6.5 TD throttle cable will fit the 94-95 trucks as long as you get the proper brackets. (there is a knockout in the firewall)

The cable attached to the little crank assembly and was somewhat adjustable to allow things to closely resemble the position of throttle pedal to actual engine fueling.

This is a far cry from perfect but the ones I have seen I could have lived with.

The only issue is to be sure that the tranny is seeing enough pressure to correspond to the engine power. (Low line pressure under power can and will eat clutches)

My one question is what did you do to keep the SES light from coming on due to the lack of signals from the IP??? (remove the lamp) :D

Jims thoughts to using the aftermarket stand alone for the tranny are a good one.

This just depends on your budgit.

***Mobilvet***

I personally would not recommend the manual conversion. Its not a cheap trick. The work itself is not hard to do but I am not totally convinced that its worth the headache.

Make no mistake here, if you have ready a few of my posts you will quickly understand I have no love of the electronic wizardry on the newer 6.5's.
However that said, once the DS4 system is working right with a remote PMD and the turbo controlled with a device like a turbo master most of the issues go away.

A well setup DS4 with all the late updates and a good chip in the ECM and these things run sweet. The driveability is marvelous and they are extremely well behaved.

My 95 Dually (DaHooooley) has the 5521 pump with an aftermarket prom in the ECM as well as the turbo master, large exhaust minus the CAT and this beast runs so smooth and nice.

The secret is being sure the electrical system is in good health as far as connections and such.

The DS4 pump IF fed clean fuel will in most cases last a very long time.
The factory dixie cup fuel filter is a joke to say the least. Toss the little beast and install a nice Racor fuel management unit that can pass 35GPH. These engines move a fair amount of fuel through the IP during normal operation.

I replaced my fuel filter with the Racor 230 R2 and tossed the factory unit as it was leaking anyway.




Good luck

Robyn

[DickWells]

:)Well, I'll try again. Thought I posted a long-winded thing on the Mech pump yesterday, but I can't find it today!
I put 30K plus miles on the Sub with MIP, towing, and really enjoyed the difference in reliability. But, there are a couple of issues that some folks might not want to live with.
My mods to the TPS and mech cable were relatively simple, and turned out to work smoothly as far as throttle control, but, the Sub will sometimes refuse to shift out of first gear. Fix is to throw it into neutral (4L80E) and shut off engine, turn it back on and start it up, shift back to OD and you're on your way. For a while. Varies. The first time it happened, three years ago, on our first post mechanical trip, was in WI, after towing from VT. Did it again a couple of times that day, then not again for several thousand miles. This last Christmas, back home, we put the Sub on the road for a couple of months. Had to do the shut-off routine several times a day for the first few days, before it settled down.
The other issue is that to get a shift when you want it, you need to lift your right foot. I like this part, because I'm a stick shift guy anyway.
Based on these little tidbits, it shows that Jim is right about the stand-alone trans control computer. Problem for me is, the computer listed 3 years ago for something like $650, plus another $150 for the cables!
You'll never have a quicker starting, better running 6.5 than when you put in a well put together 4911 pump. I get lots of white smoke and shaking on cold start-up, but it smooths out fast and settles down. Starts hot or cold with just a quick bump of the starter. After glowing, of course.
The MIP has smaller fittings at the pump end, so get one complete with lines if you can. Addapters are available.
My brand new pump cost me $1200. Worth every penny. Two wires, instead of half a million. I never hooked up the fast idle solenoid. Don't need it.
Don't know how you get a mechanical boost control by just swapping pumps. I still have electric control of mine and it works fine. I did bypass the vacuum solenoid years before I went mechanical, cause I couldn't keep the boost with the lousy thing hooked up. I do have Kennedy's boost level fooler on the manifold, still.
Would I do it again? In a heart beat. Wish I could do it to my DM. I don't trust anything electronic, but I sure enjoy using these modern inconveniences when they're working right.
Good luck to anyone who puts a MIP in their 6.5. Just ask for info here on the old DP, and you'll get more than you ever wanted to know.
Dick Wells:)

[DickWells]

:oI've been off here for so long that I plum forgot to page through the thread! Found yesterday's note, as well as all that other info. Like the DP guys need to read my drivel, after looking at 3-4 pages of stuff!
Sorry people.
DW:o

[mobilevet]

Thanks for all the great replies.. much to consider.

Any thoughts on taking the air snorkle out? I have the air box off but did not see an easy way to get the snorkle out of the quarter panel?? Just rip it out???

Also, do I need to put anything over the now open hole on the side of the air box? No, not a cover because I know that is where the air comes in, just something to keep big stuff/water/etc out?? just a thought.

Thanks again

[DA BIG ONE]

Think the DB4 might be a good choice?

[Peter J. Bierman]

I have considered a DB4 but it's (much) more expensive, not availabe used and not worth it.
The DB 4 does not nesecairily givesmore fuel unless set up for it, and you need a lot of modification to do anythingwith that extra fuel.
A marine DB2 will do more than the engine in trucktrim can handle.

What is worth the trouble and the cost is the PCS standalone computer!
I run one in the TTD Blazer and am very pleased with it and even more with the support from PCS, even after a couple of years, no problem what so ever.

This unit is so universal, you can use almost anything to control it:
TPS ( positive of negative ) Boostpressure, rpm, you name it.
Best thing is you can program it to perform best with your engine and or taste of driving.

This it realy a cool unit! :cool:

Peter

[Chief919]

On the TPS, has anyone tried using the TPS setup that AMG uses on the 6.5/4L80E combo in the M1114. It is a simple straightfowrd setup that uses the 4L80E on a vehicle with no other computers at all.

[garysleeman]

I looked for the article this thread referenced but couldn't find it could someone post a linK?
Thanks

[trbankii]

I’m going to guess it was this one in the Members’ Section: http://www.thedieselpage.com/members/features/appconvc.htm

[garysleeman]

It sounded like it was 96 model year specific. I don't need transmission info just PCM I'll start another thread.