I may be in need to use my little truck with a Ddec 111, for some serious grunt work. From what I understand the design keps you from turning them up too much, and depend on it staying together, unlike theDDEC1V. The injectors I know could use freshening up, so I think a new six pack is in order, has there been any known problems with the reliabuilt injectors?? The turbo is the original and ready for a replacement, probably a BW, but not 100% sure what to go with. I do know several years ago, when I had stewart and stevenson inframe it, they did a software upgrade, even though I told them I didn't want or need it, they told me it was the law, and they had too, not sure on this. I do know I lost a little power and mileage. If I go this route, I need to get all I can, but do not want it to be enough to hurt the engine. Any suggestions on what to do with it, and who has the best turbo prices?
The “ upgrade” was probable lo nox, from what little I’ve read about it, all engines built after 1-1-2000 were built with it. All previous engines, had to be upgraded, ( supposedly at no extra cost to Owner), paid for by Detroit. When Overhauled. I’ve read they retarded timing 5 degrees, and results in a 5% decline in power and thus fuel economy. Cat, Cummins also were sued by epa, all three paid big fines. Detroit especially, as they were the worst offender. The BW can be bought for $650 all day long. Injectors can be checked by computer hook up, I’ve got reliabilts, replaced 2 so far, 1.@ around 900 k, only problem, turns out was an o-ring. Replaced it with s no name cheap rebuilt injector. Replaced 2nd one @ 1.1 mil.selinoil was cracked, leaking fuel bad into valve cover.Replaced it with Reliabilt injector. Of course new o ring kits, with carbon fire crush rings. I think I have a 3 rd on going bad, might be just an o-ring. I see fuel seeping our around # 3 exaust port, gasket is a little wet, just like when the first one went bad, looks like oil, probably fuel. All in all, I’d say reliability are the best out of all three Detroit, Cat, and especially Cummins. They’re $400 ea. 6 pack $2000. I plan on a 6 pack @ OH. Next year. Got 1.3 mil on OH now. I’ll keep the reliabilt for a spare. Still have an xtra core from first replaced injector. All I know about dedec 3 vs 4 is, dedec 4 has 4 sensors less, fan, temp? And? Not sure. Replaced by a pdmi? module in fuse panel. Maybe a piston upgrade also. If so I’d guess the piston upgrade is the only real issue to look into. Good Luck, I’d just run it,as is, see how it does. Might be surprised But that’s Me.I choose to take my chances. I’m no guru, but have ran 2 different dedec 4 over 19 yrs. I pretty much don’t touch them, unless there’s an obvious problem. Current one, has only had 1 overhead, 2 turbos, and 2 injectors, since OH.over 1.3 mil. Currently.
The issue is, if I do this, is that I will be asking the 12.7 to do more than it ever has and compete with the big dogs. I may need to run it on the haul road, so I need to squeeze every ounce of power I can out of it that it can muster, but not so much that it self destructs, either. From what I have read, the 12.7ddec111 has a different piston and maybe even connecting rod than the ddec 1v and also has no piston cooling jets, so you can not produce as much power with it as you can the 1v. Way back when I had it inframed they told me it was a little low on manifold pressure, and it could be either the turbo, or the injectors. Both of which had right at 1 million miles on them then, now it is probably in the 1.4 mil mile range. This truck is too light for what I need to do with it, but I don't use it for anything anymore, and it owes me nothing, so if I can put a few thousand bucks in it and take it easy and get by with it for three months or so, it would be well worth it. It is just an option I am thinking about, since I have it setting here, I am not sure which way I will be going, but it may be better than going in debt .
Fans were manual in those days when necessary to override the automatic spinning function up front. OP wants to run with big dogs. I say forget it. Appreciate the engine, love on it, nurture it and just do what you can. Don't abuse it.
The DDEC 3s didn't have piston cooling nozzles but as long as you keep an eye on your EGTs, you can run them at 600hp with no problems. If you need new injectors, upgrade to a bigger set. If it's a 430/470 they'll be 5575s and a set of 5915s would take it to 500hp, a set of 7014s would take it to about 550hp and will run cooler than an ECM tune. A 171702 turbo, although not ideal in my opinion, is cheap and would get you about 50hp.
You know, after they went up to 500 hp, they also added upper cylinder cooling passage in top of liners.Both my dedec 4 s failed at 825k due to dropped liners. They’ll never admit it, maybe I’m wrong, but I suspect Detroit pushed the little motor too far. A Detroit mechanic once told Me, they didn’t see it very often, before the upgraded cooling in liners. 430/470 was the best fuel economy motor.While everyone else was coming out with 14 L. Detroit was trying to squeeze more from the tried and true 12.7 Just my opinion, but when they finally came out with 14L , it was a 500. 12.7 got demoted back to 470 . If I remember correctly.Im surprised they didn’t upgrade yours when OH. Cooling nozzles for wristpins,and upper cylinder cooling jacket to combat upper cylinder scuffing.I see both kits are still available. That little extra hp, they squeezed out, was mainly for marketing during the hp race.I love the 12.7s but honestly, they’re reputation has gotten overblown.Some of the “ improvements” came at a cost. IMO.Stock set up, trouble free operation. The Truck should do the job as is, using gears to your advantage, and don’t let it get hot.Maybe put a turbo on, as PM. But why waste $$ on injectors, if it runs good, has good fuel economy, injectors are probably fine.
I would run the serial # to find out exactly what you have. Not all ddec4 had cooling nozzles, only p and b models, e and m did not. Never know what your ddec 3 was built with. Dealer can tell you for sure. Detroit 800# on valve cover, give them a call.
I actually had better luck out of my DDEC111, than the 1V, but I also bought it with just 200,000 miles and ran it myself, the 1V I bought at 590,000 when it came out of the shop with a fresh rebuild. My 111 never had the torque the 1V did though and when stewart and stevenson inframed it they also did a software update, that I told them it didn't need, and it never had quite as much power, nor did it ever get quite as good of fuel mileage.
