Riddle me this....

[rowland]

Hi Guys,



As fair warning, this is going to be a bit of a long post, but my truck has some serious issues that are beyond my ability to troubleshoot. I doubt anyone will remember, but a couple of months ago I posted about my '89 with a slow idle and loosing power. After replacing the lift pump and putting a gauge on the fuel supply, I decided that it must be the injection pump dieing and ordered a new one. I've been fighting this thing ever since and still don't have it running right. I'm about at my wits end and need some ideas. History is as follows:



- Truck starts idleing slower and loosing power over about 2 weeks. No longer smokes at WOT and boost falls from 19 psi to 12 psi. Still starts instantly and runs smoothly on all six, just acts like it's not getting full fuel. Fuel pressure gauge after the filter shows 5 psi at idle so decide to replace injection pump.



- While I'm waiting for the injection pump, I order new injectors (Bosch 190's from Pier's).



- All the parts arrive and I install, following exactly my Cummins manual. Truck starts and runs, but now idles at 500 rpm and has ZERO power. As in I can't even get the boost gauge to budge. It still revs freely with no load, just no power under load. NO smoke of any color from the tailpipe.



- I call the fuel injection shop and attempt to troubleshoot over the phone. After checking all connections, etc. He has my try turning in the smoke screw. That does nothing. I then trying turning in the power screw one turn. That instantly woke the truck up! Idle was at 800 rpm and could get about 17 psi of boost. Had quite a bit of turbo lag however.



- Now that I have it running, I notice that the pump is leaking fuel. Tracked it down to a hairline crack in the housing. great... So I called the shop and they sent me a new one under the warranty.



- Installed new pump. Once again idle was at 600 rpm, but I did have some power, it just wasn't very good and would get bluish white smoke from the tailpipe when reving. Playing with the timing did nothing, but once again adjusting the fuel screw brought the idle up to 800 rpm. Power however was still kinda lousy and could only get about 12 psi of boost. The engine also didn't sound "quite right", sort of a hard rattle noise at idle. Very long turbo lag and the transmission wouldn't shift until I hit redline at 2500 rpm.



- So today I tried changing the injectors back to the ones I pulled out of it. Noted that the 190's were already sooted up real bad. Doing this restored the beloved cummins clatter and brought my idle up to 950 rpm. I can now get about 17 psi of boost, but power is still lousy and it builds boost slowly. Under WOT excelleration, it will slowly build boost to about 13 psi, then sit at 2500 rpm for several seconds while the boost drops off. Then it will upshift to 2nd and repeat. Once I hit 3rd, I can get 17 psi. wierd, no? No smoke visible of any color.



- It's obvious that something is still wrong with the truck. It's certainly not driveable in its current state. I'm completely stumped and very tired of having my head in the engine compartment. What the heck is the deal with this thing? Any ideas?



Isaac

 

[Moab4x4]

Going through the list of variables:

Fuel Flow and pressure: It sounds like you have done all with that one (unless you could have a compromised High Pressure fuel line)

Timing: You have messed with this one a bit

Engine Compression?? Do you have a way to test the compression in all cylinders? HG, burned valve, crack around injector,... Compression test would be a good diagnostic. On the other hand, Was the soot on the 190's even on all 6? IE is this an all cylinder thing or are we losing a cylinder or two?



BTW I am NOT a diesel mechanic so these ideas are worth what you paid for them.

 

[rlyons]

I don't know who rebuilt the pump but it sounds to me like you may need a new pump shop. Pump leaking should have been found on test rack. I may be wrong but sounds that way to me.

 

[csnider]

I would think the 190s are smaller injectors than your stock ones if your truck is a 89... I agree that maybe your pump shop might not have adjusted the rebuild right. . maybe you can take your pump to a better shop and have them check and re calibrate it on a test bench.....



Oops didn't realize you had a intercooled head on there. . is you boost tube to the afc sealed up good?. . look in the AFC and make sure the fuel metering pin isn't stuck

 

[Greenleaf]

Sounds like a combination of a few things. I'd say the shop isn't setting the pump up correctly and because you recieved one that is leaking means they are not testing the pump on the bench..... not good unless you only paid for a reseal job and nothing more.



The injectors alone will change the way (speed/sound/smoke) the engine operates.



You turbo lag makes me question if the AFC is adjusted correclty as in a lack of fuel per boost. You have boost presure into the pump top.



-S

 

[rowland]

The pump shop is fairly well known and assured me that they bench test all their pumps. Anybody have any experience with Industrial Injection? I even talked to their technician on the phone. I suppose it's remotely possible that their equipment is way off, but they seem to know what they are talking about.



I could fiddle with that AFC until my turbo lag went away, but I shouldn't have to with a new pump. Maybe my turbo is on it's way out, but I would expect black smoke if that was the case and it spins freely. I double checked the boost tube, and it's free and clear.



The old injectors that I took out were a set of knock off's. Not sure where they came from, but they no markings on them anywhere. Spray pattern looks roughly like 185's, but with slightly smaller holes. 190's should have been an improvement.



Soot on the injectors was even across all six cylinders. No oil in the coolant or vice versa. It also runs "evenly" (although poorly) on all six. Doesn't sound like it's a sick cylinder from what I can tell.



I haven't pulled the high pressure fuel line yet. I have no idea how that would get fouled up, but I can certainly check. It would fit the symptoms.



The only other thing I can thing of is that the new pump they sent me is a 114. The old one on my early '89 was a different number (that I don't have with me right now) and was supposedly superceded by the improved 114 pumps after only a few were installed in dodges. It was a direct bolt up, but perhaps the banjo bolts or something are slightly different? I have no way of checking that.

 

[Greenleaf]

Ask the pump guy what the cc's (fuel rate) are. I could look in my pump manual to give some specs. I'd have to find the correct one as I have several and one of them lists the specs of different VE pumps.

 

[dpuckett]

Non intercooled (114)- 78mm/ stroke

intercooled (184 & 205)- 74mm/ stroke



This is from the data tags I have looked at on various engines through the years.



I'd say it's time to find a new shop. If they cant even find a leaking pump on a stand, they dont need your business. Unless it got cracked in shipping, or you dropped it .



How many holes are in the tips of your take out injectors? If they are six-holers, chances are it's stock intercooled injectors. Or it could be something completely different. These engines were used in a LOT of different applications.



Double check your AFC line- it can have a hairline crack in it and you wont be able to see it if you arent at the right angle. Better yet, look in the subforum about the discontinued parts, and look up my AFC fix (thread is about 2 years old).



Daniel

 

[rowland]

Well whatever I had on the engine was actually a pre-114 pump. The only visible difference was that the throttle return was a coil spring attached to the gear case, rather than the typical spring on the throttle shaft. My early '89 (Nov '88 manufacture date) has a few quirky things about it. I did have the shop check the flow rates and they assured me that they were identical and that the 114 was the prefered pump. I will check my tag tonight and see what the flow rate is supposed to be.



And no, I didn't drop the pump or anything like that. However I could tell under the shiny black paint that it had been gotten beat up in it's previous life. Not sure how a pump could get that hammered, but there were dents and dings in the body, top etc. I'd be willing to bet it didn't come out of a pickup. The crack was just a hairline below the hex plug on the throttle shaft side. It's possible that it only leaks when being rattled by a diesel. Otherwise, yeah I'm a bit disapointed.



The injectors I took out were a five hole design. No idea what they are, as I couldn't find any marks on them. I have a intercooled head that takes the 7mm injectors, so they aren't stock.



Is it possible for a hairline crack in the AFC tube to make that much difference in performance? I would think that with the positive pressure supplied by the turbo, it would require a major break to make a noticable difference. Will check that again tonight.



Isaac

 

[rowland]

Ok, according to my parts book for the engine, it came with a "VP-14" pump that flows 78 cc at 2500 rpm. Is there was way compare the various part numbers for the externals (banjo bolts, lines, etc) on-line?



Isaac

 

[rowland]

Further Fiddling...

"Tuning" the AFC (cone to deepest setting, starwheel in 1 turn, smoke screw in 1. 5 turns) did wonders for my turbo lag, but still very low power at high rpms. I'm back to thinking that it's not getting enough fuel. I didn't get a chance to pull the high pressure fuel line tonight, but I'll do that tomorrow.



Still no smoke either under acceleration or at WOT, and with my current pump setting I should have something.



I did check the boost line to the AFC and it's fine.



Isaac

 

[cerberusiam]

Every pump is going to react differently on different engines. You will have to tune it for best performance. All the pump shop can do is go by CPL settings and get it close.



The injectors you have in sound like stock ones. If thats the case you will have to dial in some more fuel to get a lot of smoke at WOT. This is assuming you turbo is good.



Run the star wheel all the way down and test your smoke then. It sounds like you simply need more fuel. Turn the full power screw in some more and back your idle adjustment screw out all the way and set the idle with the full power screw and see what that does.



The hard rattle sounds like too much pump timing. Could you have got the pump in one tooth off? Have you found true TDC and set the pump that way or are you using the timing pin? Where are your timing marks on the pump and housing in relationship to each other?

 

[Greenleaf]

Non intercooled (114)- 78mm/ stroke

intercooled (184 & 205)- 74mm/ stroke



This is from the data tags I have looked at on various engines through the years.



Daniel

I read that the spec is mm3 which Jay told me is mililiters??? But some pump shops like to use cc's of fuel/stroke. Jay gave me the master convert disk but does not list mm3



I have a tag here that states "fuel rate @ adv. HP 97 mm3/stroke.



The max advertised delivery for the VE is states as being 120mm3 (we know we can massage that a bit higher)



So I need to look into converting mm3 to cc's The 78 and 74 mm3 sound correct.

 

[dpuckett]

1000mm3= 1cc. 10mm=1cm. Cube it, and your 10mm becomes 1000. 1milliliter=1cubic centimeter(cc)



Actually, the mm3 is more correct- it is cubic millimeters. To be exactly correct, the pump shops need to phrase it as 100cc/1K strokes. Makes it easier to ensure even flow from all the ports.



There is a VE stock setting for 120cc? Cool.



-DP

 

[Greenleaf]

Apparently so... the book lists 13 and 14mm plungers so I would imagine that 120 (posted as mm3) is for a larger plunger than our 12mm plunger. It has been stated and pass around that Brian( KTA ) is having 14mm plunger/heads built custom. Maybe so but my manual (available to everyone in the world) lists the 14mm plunger/head assy used in a OEM application and not hot rod Dodge Rams... LOL

 

[CSchafer]

I'm pretty sure that I read somewhere about why KTA has them made. Was somthing about there wernt any left around and they were no longer being made. But I bet his design specs are pretty close to an original.

 

[csnider]

Another thought I have is, before you get rid of those 190s make sure you get the right pump or pump settings. . those old five holers might work better only because the pop-off pressures in the new 190s are too much for the pump to handle in it's current state. .

must be a total pain to have to keep removing the inj pump...



Too late for this but,when I had my 93 VE rebuilt, I chose a place that would rebuild my old pump instead of doing the exchange thing .

 

[rowland]

Yeah, I'm kinda dragging this thread back from the dead, but I hate it when people ask for help trouble shooting something and then never post what the solution was. Also, I'm more than a bit torqued right now and need to rant a little. This may be long...



So after playing with my pump and everything connected to it until I was blue in the face, I caved and took my truck to a local shop with the cheesy name of "The Diesel Doctor". They are really the only place in town the specializes in diesels, so I didnt have much choice. They pop tested my injectors (good), checked my compression just in case (all above 400 lb) and then set the timing. They called today and said it was all fixed so I went down to pick it up. They mentioned that the transmission was slipping between shifts.



So I grabbed the keys and took it for a test drive. Sure enough the transmission was slipping really really bad. Couldn't accelerate worth squat. So THAT's why was having a heck of a time troubleshooting this thing. The transmission wasn't letting me load the engine! I'd suspected that before, but was in denial, since I didn't want to spend any more money on this thing. It was hard to tell with the slippage how the engine was doing, but it seemed ok. Sounded fine and reved good.



So I went in to settle up and found they had retarded the timing from 1. 65 mm to 1. 23 mm. hmm. . that didn't sound right to me. I checked the engine tag and sure enough, stock is 1. 40 mm. So I asked why they had done that, and the manager came out to answer my questions. The following is for your reading pleasure. I can't believe this was a diesel truck shop I was talking to.



Me - "Why did you set the timing to 1. 23 mm? Stock is 1. 40 mm. "



Manager - "No 1. 23 mm is stock"



Me - "uh... if you look on the engine, it says right on the tag that 1. 40 mm is the stock timing. "



Manager - "Well 1. 23 is what our manual says. "



Me - "ok, what manual are you using? I've never heard of that. My cummins manual says 1. 40 mm, and it says the same thing on the engine. "



Manager - "We've been working on these trucks for years! 1. 23 mm is what works best for our climate and conditions. "



Me - "Um, all I wanted done was the timing set to stock settings... "



Manger - "Well with increased fuel the timing should be retarded"



Me - "I have a stock pump settings right now... "



Manger - "Well with the stock 5 hole injectors we set to 1. 23 mm, with 6 hole injectors we would have set to 1. 40"



Me (I'm thinking, hmm my stockers were 4 hole) - "I just want it set to stock 1. 4 mm. I think 1. 23 is too retarded"



Manager - "Does it run better now?!"



Me - "It seems to, but it's pretty hard to tell without loading the engine. "



Manger - "Well we can change the timing to whatever you want, but I don't EVER want to see that truck again!"



Me (in shock at this point)- "I think you have a deal there... "



... and he stomped off.



Wow.



I never raised my voice or anything. Truly a new class of ignorant jerk. He certainly doesn't have to worry about me coming back again.



On second thought, I just took my truck back. Certainly don't want those fools messing around with it anymore! Seat of pants is that the timing actually feels pretty good. Once I got the transmission fluid warmed up, I could hit about 18 psi and 1100 F in overdrive. Starts right up cold and doesn't white smoke or anything. Makes me wonder if they even knew how to set timing correctly or if they had a "special" method. Hard to tell through all the BS that was thrown at me.



Anyhow, as icing on the cake, now I need to do something about this transmission. I'm a bit leery of shops in general right now (this is only the third time I've ever been to one), but auto trannies are beyond me repair wise and I doubt I can come up with another junkyard replacement in this little town. Yeah, it wasn't a good day.



Isaac

 

[dpuckett]

I'm a bit confused about the injectors- 6holers are stock for IC trucks; 4holers stock on nonIC. But moving on... .



Stock for a nonIC truck is 1. 40; stock for an IC is 1. 25. The general consensus around here is that 1. 40 is the minimum for either breed of engine for maximizing power and MPGs, along with cutting smoke, etc, etc. 1. 5-1. 6 is where I have had the best luck. So, I'd have them reset the timing, or if you had marks, just set it back to where it was.



transmission slippage is bad. I'd go with a better known vendor for an exchange, or find someone that can rebuild it with performance parts, esp the convertor. Mom got a stock convertor in her rebuild, and the only difference is the lack of shudder at 20mph under hard acceleration. Still sloppy as a hog lot after a hard rain.



-DP

 

[rowland]

heck, I was a bit confused about the entire conversation. He obviously had no idea what a stock injector was. The only thing I can think of is that they were trying to set to the 1. 25 settings for the IC trucks (what's 0. 03?). But the way the conversation went, they obviously don't care to admit mistakes like no realizing that there was a difference between IC and non-IC trucks. A more pig headed man, I have never met. What kind of shop tells paying customers not to come back? I wasn't fighting with him, just trying to discuss the situation. Yeah, I figure I can bump it forward a bit later. Easy enough to do.



I did pick up on the fact that they prefered Fords, so that gives me another reason not to go back there.



I'm pricing transmission rebuilds today. With shipping to Alaska, exchange on heavy parts usually isn't cost effective, although that would be my prefered method. My garage is way to small to be changing trannies in, but I'd do it anyway just to avoid the hassle of finding a decent shop. sheesh, I'm still disgusted.



Isaac