Injection pump swap.

[6.542762mw]

Ok its time to move away from the computer set up on a 94 truck and go to none computer 93 or so. I have the pump already what else is needed?
Lines seem to be different sizes...would still like cruise control...anything else? Dazzle me with your knowlegde! Thanks guys!

Mark

[Bobbie Martin]

You might want to Click Here (http://www.thedieselpage.com/newprod.htm) and scroll down just a bit.

[BobND]

Why do you guys hate the DS-4's so much? In 180,000+ miles my '94 has had the pump replaced once, before I bought it at 54,000, or so miles, and the FSD replaced once, more recently.

A friend of mine used to own a '93 that he purchased new, and even his DB-2 had to be overhauled a couple of times while he owned the pickup. (He now owns a PowerChoke.)

The DS-4's start in COLD weather better that any DB-2 equipped unit I've ever had, and get better mileage. I attribute the better starts to positive conrol of injection timing during cranking by the electronic pump. I appreciate the feedback idle speed control for cold startup operation, and when the A/C kicks in. The PCM shifts the 4L80E flawlessly.

So why throw modern technology away to go back to the "stone age"?

Exactly what horror has turned you guys so against the electronic system?

[6.542762mw]

You may want to do a search on this site to see how many issues there really are. Stalling is the biggest issue and its trully not the injection pump itself..the PMD failure rate is extremely high. Look on ebay and you will find fixes and tricks of all sorts to correct this horror. After the 94 stalled with out warning for the 100th time on the freeway with huge trucks on all sides with your family as targets and after replacing the PMD 2 other times at 270.00 each its time to replace the POS! Also as you can see someone wrote a book about changing it out to the old unit, I have yet to see a book wrote on pulling the old one out and updating to the DS4.

[NH2112]

I think the reason so many people are going from DS4 to DB2 is because there's nothing else in the loop to go bad on a DB2-equipped engine. On the 2 GM diesel-related sites I frequent I'd have to say the most common problems are related to the DS4 and its associated electronics, and the answers to these problems generally involve having to spend large sums of money to replace the pump, PMD, or both. Many people have to do this about as often as changing fuel filters, it seems. The DB2 may be Stone Age but they tend to last well over 200K miles, and when they do stop working all you have to do is fork over about $300 for a rebuilt one and spend maybe 2 hours total for the R&R.

[rjschoolcraft]

There really aren't that many people who are doing the conversion. There are some (Bobbie Martin) who are very outspoken about the DS4 and would do anything to eliminate it, but I think far more people are experiencing improved reliability out of the latest DS4 pumps. My pump and FSD were changed together under warranty after 75,000 miles for a smoking issue. My current pump has done very well. I have over 160,000 miles on this DS4 and have only replaced one FSD. This FSD has about 40,000 miles on it, so I got about 120,000 out of the other one.

[6.542762mw]

Roonie is one of the lucky few, who have had warranty and had to replace the pump and FSD only once...but thats still one more time than my 93! Never! Near 200k! Never stalled in traffic! Never failed to start! Never cost a pennie to fix in any way! Yes I agree the newer DS4 are getting better, the FSD is getting better, the fixes are getting better and you see many fewer issues, but never failed is never failed. I cant say that about the 94. Money spent on this is nearly 2000.00 with parts, time down, labor...and dont forget the tow truck fees!

I dont want to dis any DS4 owner, sorry if I did!
But this 94 has gotten way too friendly with the local tow trucks and as you can tell lost my trust. (We dont even want to start on what my wife thinks) its getting harder and harder to explain the cost of this DS4.

[Turbine Doc]

I'm in that mix as well, remote mount of driver is the solution, and I'm a believer in the out of the engine bay camp.

[NH2112]

The DB2 on my recently-blown 6.2l was the original, and the engine died with about 290K miles on it. One weekend last summer I swapped a used pump on to check if that was the cause of the problem I was having, but it wasn't, so the original went back on.

Remote mounting and/or cooling the PMD is a "solution" to a problem that never should have existed, along the line of the "bolt forward assist" added to the original M16 to help alleviate jams that never should have happened if the original design had been worth a darn. Besides, even remote-mounted and cooled PMDs have problems, although not as often as stock ones.

I have yet to see a DB2 die from anything besides old age or contaminated fuel, and only 1 or 2 instances of the latter. As far as cold starts go, mine has started just fine over the past 4 winters with just a single battery and 2-3 hours of block heater time, rarely needing more than a couple seconds of cranking and 10-15 seconds of running to smooth out, even when not plugged in.

I guess it all boils down to personal preference. I prefer something that has little to no chance of failing even if it's not quite as efficient.

[Bobbie Martin]

Originally posted by BobND:
Why do you guys hate the DS-4's so much? In 180,000+ miles my '94 has had the pump replaced once, before I bought it at 54,000, or so miles, and the FSD replaced once, more recently.

A friend of mine used to own a '93 that he purchased new, and even his DB-2 had to be overhauled a couple of times while he owned the pickup. (He now owns a PowerChoke.)

The DS-4's start in COLD weather better that any DB-2 equipped unit I've ever had, and get better mileage. I attribute the better starts to positive conrol of injection timing during cranking by the electronic pump. I appreciate the feedback idle speed control for cold startup operation, and when the A/C kicks in. The PCM shifts the 4L80E flawlessly.

So why throw modern technology away to go back to the "stone age"?

Exactly what horror has turned you guys so against the electronic system? I don't hate the DS4, I hate having an unreliable vehicle. This from a guy whose hobby is British cars with Lucas components! We have a 1995 Suburban that we have owned since new. Its my wife's daily driver. We really like it, but after 5 or so DS4 failures in 120,000 miles, a change was needed. I had already tried the FSD cooler, etc. Still the problems persisted. Maybe we had more problems than most, but I don't think you will find anyone that has owned a DS4 for any length of time that hasn't had a problem. So I installed a DB2. It has never left her stranded, something that cannot be said about the DS4.

I've also modified the alternator for more reliability, but I did not change to a generator. So I'm not saying that going backwards is always the fix. If I thought a DS4 could be made reliable, I would have kept it. I did lots of homework before I did the swap and consulted with people that I trusted and had more knowledge of the DS4 than I did. I was prepared to spend whatever it might take to get a DS4 rebuilt to a reliable specification. I couldn't find a way to do that. Even the Stanadyne dealers admitted they will fail without warning at any time.

Our DB2 equipped Sub has no starting problems, gets about the same fuel mileage and the 4L80E shifts fine. So the reason I threw away the modern technology is that its unreliable, plain and simple. If the DS4 and related electronics works for you, great, I'm happy for you. It didn't work for me so I found something that did. Others expressed the same interest, so after several inquiries about how I did it, I decided to put the information out.

So what horror? Unreliability. While the DB2 might give me problems over time, I trust it to at least get us home. I don't trust a DS4 to do the same.

[BobND]

Bobbie,

Maybe the "Prince of Darkness" helped Standyne design the FSD!

I guess I've been lucky with mine, having only the one failure, at which point I moved the new one to my own LARGE cooler, mounted behind the LH headlight.

Living in a cold climate, I sure appreciate how quickly and cleanly it starts, and controls idle speed on it's own.

More or less, I see that system in the same light as any modern electric fuel system for reliability. And these diesels don't have a corner on the market for flaky modern elctrical stuff. Look at all the electrical fuel pump harness connector failures in the newer gasser pickups and Yukons. That will leave you sitting on the side of the road as quickly as a FSD failure. And GM is not alone with that. Take Ford and their fire-starting cruise control electricals.

What did you do with your alternator improvement?

I have waited for YEARS for mine to fail. A buddy had '94 he bought new, and had a alternator bearing failure within a couple of weeks, and a handfull more after that, over the years he owned the truck. I have been expecting mine to fail to the point I carry a spare, along with a belt, and tools. It has over 180,000 miles on it, and, when I checked it recently, the bearings were still tight and smooth. I wonder how long it will go?

[Barry Nave]

Bobbie Martin
It is strange how your 95 differs from my 95.
I'm on my #2 pump. R&R back at 45K. Now have 150K. Though I will say I'm having code 35 issue.
Can't remember that guy in the other country that R&R the opticle(sp) on top of the pump that solved the code 35. This may be all I need.
All in all my 95 has not been like yours. Why could this be? 4 pumps. I would of changed also knowing I be having this truck for many years.
I'v got to much in it and if I did sell the truck the buyer would be coming back every time somthing need to be worked on :D

[JohnC]

Me too!

My '95 got a new (improved) pump at 27K. That pump ran fine until I traded it last fall. I had to replace the FSD once at around 120K. I ran on the pump FSD 'till about 50K and on a used Beta cooler/fsd up to 120K. I would have gone back to the pump mounted one but I think I bent a pin trying to reconnect it. Not perfect, but not weorth spending a lot of time and money to "correct". Now if I had had 5 failures like Bobbie....

[Bobbie Martin]

What did you do with your alternator improvement?
This is kind of long, but you asked about the alternator, so here goes. The alternator has been so unreliable, it would do a Lucas alternator proud. After several failures with the parts house rebuilds, I went to a local shop and had them build me a unit with the Iceberg (http://www.alternatorparts.com/iceberg.htm) case, larger bearings and generally uprated components. I'd like to say everything was fine, but after a year or so the front pulley came off (those pressed steel pulleys are worthless) and a year later a bearing seized. The shop was very good at repairing it even though it was past their warranty period, but still it was aggravating. The latest problem was a bit more perplexing. Its probably been a year or more since this happened. The batteries kept going dead. Well, I figured the alternator was bad, so back to the rebuild shop. Put it on the tester and he reports, this is a good one, no problems, puts out over 100 amps, etc., etc. Hmmm, must be the batteries. Well, after paying the proration I replace both batteries and it was OK for a few days, but then back to having dead batteries. OK, its getting old by now. So out comes the alternator, but I figure I'll take it somewhere else and see what they say. Checks fine, I'm told. OK, well that can't be. I'll try one more place. And, of course, it checks out fine. I watched all three places check it so I'm pretty sure its not the alternator by now. By now several weeks have gone by, I have new batteries and three independent shops telling me the alternator is OK. So I figure, its got to be a broken wire, although they all look good & ohm OK. I run a complete new wire from the alternator to the batteries, thinking this has to be the problem. Batteries still are going dead. By now I'm getting pretty aggravated. I've checked everything, there is really nothing left. It sure acts like a bad alternator, but it can't be. Well, out of desperation I decide to go buy a rebuilt alternator from the parts house. Put it on and no more problems! Well isn't that just spiffy, how can the alternator repeatedly check good but still be bad? So, I take it back to the rebuilder and tell him the problem. It seems that the internal wire that connects the power to the terminal had broken, but would still make contact. He figures that on the tester when the wire was connected with an alligator clip it made good contact, but when the nut was tightened up it only made intermittent contact. So I had it repaired and put it back on the truck. So far, its been doing fine. But, I still have the parts house rebuild alternator on a shelf in the garage. I figure it will never go bad if I have a replacement on hand. Maybe I should have tried that with the DS4!

[Bobbie Martin]

Originally posted by Bnave95:
All in all my 95 has not been like yours. Why could this be? I'm at a loss why we had the problems. It would be hard to find a diesel Sub that gets treated easier than ours. Like I say, its my wife's daily driver. She certainly doesn't drive it hard. It has towed a trailer maybe 1% (if that) of the time and the trailer weighs 4200 lbs. tops. I've changed the fuel filter regularly and added a Racor filter before the lift pump. If anything even looks bad, I replace it. Its never overheated but I still upgraded to the HO pump & twin thermostats just to make sure I wouldn't have a problem. Yet, we still had the DS4 problems. First one was replaced when the truck had less than 5000 miles. Maybe that was an omen! I guess the DS4 is one of those things that some people swear by them and others swear at them.

[gvig]

BobND,

Please tell me about mounting that remote FSD behind the LH headlight. I have been considering that too but that will put it way too close to the battery for my way of thinking. What form of protection did you provide, if any, to keep the acid fumes off of it??

[BobND]

George,

I use Delco batteries, and they stay clean, and there has been no problem with corrosion. I made my own harness, by splicing in about 3' into each wire, and soldering the connections. I made up one for my 1994, and on for a friend/customer.

I can post a photo in the next day or two, if you'd like. (I took photos when I did the move, but stupidly loss them in a computer crash, after clearing them from the camera, with no backup available.) I'll take some new ones and post them, when I get out there. Or there probably are others available on the site here, if you search.

[gvig]

Please,I would like to see how you did it.