2nd Generation Dodge 12 Valve Powertrain

I common cause to a truck that is missing is a bad injector. Tracking a bad injector is very simple. There are a few precautions you need to take first. The injectors do spray at high pressure. It tends to atomize instead of shoot at you but it still should not be taken for granted. A bad injector may have one of these problems: [*]Low pop pressure [*]Bad spray pattern [*]Clogged nozzle [*]Improper assembly (if you cleaned them and put them back together) There are a few people wondering what a miss even sounds like so this video should clear that up. By cracking each injector one at a time, the engine should miss worse since 2 injectors should…

I think you all know how I keep saying my EGT's are high at idle, never dropping down to 300, like yesterday I sat there for 15 min idling and the lowest I saw was 340. Well I got my digital EGT gauge and hooked it up and ran it and the ONLY time the other gauge was right is anytime over 400F. Below that it was way off. It is 73F outside and I got the EGT up to 700F taking off then got to a 1/4 mile downhill and at the bottom I had just got into the high 100's. My other gauge is disconnected and says 200 with no power or anything.. Now when I idle, it is just slightly slower rate than a 24V. I flew into the driveway and went the 100ft up it going about 10mph then pa…

I decided to run some more scenarios to see if my truck would ever try and overheat. I took the fan and shroud off a while back and nothing changed, still runs at 195F the whole time. It seems I only have to be doing 5-10mph to keep it at that temp.Anyways, I blocked the radiator completely off from behind it (in front of it would surely make it overheat) and the way I was figuring is the air goes in and bounces off the backing plate. Or it doesn't really go in because of the pressure of the plate. Not sure, think I have proven I am not the best at physics lol. I tried it anyways since, why not. Drove into the city to a couple stoplights and back out to my house, to…

I took the timing cover off to get some pics of the KDP and show everyone how to get down to that point. Before putting the cover back on though, I decided I better do something with that 2 tone piece of crap. I don't know who painted the engine black when the underlying paint is tan. Cummins stock paint color is tan so I think dodge may have just gave it a black coat so we couldn't see oil leaks. Anyhow I had chevy orange here (if you remember my trans) and I almost used it but I knew you all would send me to hell if I posted a pic of that, so I went out and got some red and got it all painted. Theres about 20 coats on it so hopefully it will last I figured I bett…

Heres a perk of owning a 12V Finally have 1 up on you 24vers haha. When you guys bleed your lines, it takes forever. You have to crack the lines and everything and it still takes a while. I do not run an AFC, I have full fuel if I floor it at idle until the governor kicks me back out at 3000. Well that means I can bleed the injection lines at full fuel if I step on the pedal.. A stock 12V would be in the same boat as a 24V since the AFC keeps it from going to full fuel.I had been telling Mike about this but I finally got it on tape today. The full one is 8 min long if anyone wants to see me take the lines off, blow them out, then put them back on, that way you guy…

I set my valves today, figured I would show everyone how I do it. As long as you know the firing order and valve lash (which are both on the cummins id tag) you can set the valves. This is called the valve overlap method. Basically the pistons have running mates. Running mates are pistons that go up and down together in exactly the same positions, as in they both hit TDC at the same time. The difference is that one of them is on the compression or power stroke, and the other is on the intake or exhaust stroke. To find the running mate, you simply take the firing order and split it in half. Our cummins' firing order is 153624. So splitting it in half would mean 153-624. …

I set my valves today, figured I would show everyone how I do it. As long as you know the firing order and valve lash (which are both on the cummins id tag) you can set the valves. This is called the valve overlap method. Basically the pistons have running mates. Running mates are pistons that go up and down together in exactly the same positions, as in they both hit TDC at the same time. The difference is that one of them is on the compression or power stroke, and the other is on the intake or exhaust stroke. To find the running mate, you simply take the firing order and split it in half. Our cummins' firing order is 153624. So splitting it in half would mean 153…

After swapping out gears and tire sizes I made the mistake of trusting the stealership to get the right speedometer gear for me based on their charts. $80 later the speedometer went from too slow to too fast. :banghead:I tried to do the math to figure out exactly what I needed but I got caught in the paradox of 4.11/3.55=115.8% versus 3.55/4.11=86.4%. Did I need to change the gearing 15.8% or 13.6%? :banghead: In retrospect, I'm pretty sure that this is what caused the dealer to give me the wrong part and it makes me question the accuracy of all the online conversion tables.After a few beers and remembering some algebra from 20 years ago, I figured out how to make t…

Lately I have noticed my EGT's are not very high. I have been driving really slow for a long time but ever since I took everything off (fan, shroud, all of it) my EGT's are really low. There is a steep hill here and I went up it and pressed down until it hit 30psi (wastegate not open) and just stared at the EGT gauge, and it stopped at 950F. It was 70F outside.

I think it is about that time i dive into the brake systems on this truck. There are a few issues I have and have not addressed. Firstly: My front brake pads seem to be wearing unevenly, unless the previous owner changed one without changing the other... I want to get all new pads and shoes. I also want the brake lines all flushed and bled with new fluid. I do not own any brake tools, at all. What does everyone recommend I do about this? Should I try to tackle the brakes all myself, or should i take it to a flat rate shop?Secondly: I noticed that my ABS module, that runs into the metal lines on the driver-side of the truck, has two wires that currently are NOT connected t…

I have a small oil leak or two on my truck. The crank seal leaks a little and i think the timing cover gasket may be as well. I don't know for sure because I've yet to rip the front end off and take it all apart, because of my broken ratchets and lack of air tools. I am afraid that maybe my vacuum pump may in fact be one cause of oil seepage as well. I noticed a few weeks ago, that there was a slight "film" on a transparent fuse I have under-hood. I wiped it and it looked like it could have been exhaust leak collecting, but I now realize that it is some soft of oil hitting my radiator fan perhaps... Could this be? There is light oil gathering on the radiator hose…

I made an article on fuel pressure and am having some issues. I think I know what the problem is but I figured I would keep tabs of the problem on a thread so someone else can learn too. In that article, my fuel pressure tops out at ~22psi. It is supposed to "never fall under 25psi under a load" so the fact that it was just idling and couldn't get to it (even when at 2500RPM) tells me there is something going on. After restricting the return line, pressure rose and I stopped restricting at 30psi and it remained at that pressure throughout the entire RPM range. Ok, bad overflow valve. Got the new one in today and stuck it in. Pressure is now normal. 17-22psi idle…

I know a lot of guys want to mess with the pump a little or just make sure it is working right so I made 6 new articles that follow that line of thought. I tried to show how everything on the pump works in as much detail as possible. [*]Fuel Plate [*]AFC (Starwheel) [*]Fuel Shutoff Solenoid [*]Governor [*]Fuel Pressure [*]Rack

I put this together today since it is probably the main problem 12v's face. Air leaks can be hard to chase, especially with solid lines that you can't replace with clear rubber lines. You can but you have to buy fittings. All of the fuel from the lift pump to the injection pump should be at a pressure of ~26psi, so you can easily use clear hose in places to track air intrusions if you have all the right fittings. Hoses can get hard, get cut, and crack which is the main purpose of using as much steel line as possible on the fuel system. Any fittings with copper washers may not be seating correctly and need new washers. Some of the main things you wa…

Maybe some of you have read this page http://mopar.mopar1973man.com/cummins/general/2-cycle-oil/cetane/cetane.htm well I am going to prove it. Words don't always get the idea across and I want you all to see what happens when you vary the cetane. First off, cetane is the ignition quality of fuel and by that I mean it determines how long it takes the fuel to ignite when heated to it's autoignition point. The bigger the number, the shorter it takes to blow up. We can show this with math and crap, OR, we can show this with some extreme fuel choices. I think you all know motor oil does not ignite very well. On the other hand, power service will ignite quickly. Motor …

Took the air filter off and wanted to see how loud it was to onlookers. I had it under the hood at first but at anything over about 20psi the camera's mic wouldn't pick it up. Yes, it is just as loud while in the cab. Now you see why going from the stock air box to a more open air filter like the BHAF makes the turbo louder.

Figure most of you have already seen something like this but what the heck. The thing I am pointing at is the hole on the top of the rocker that shoots out oil, then I am tracing it down showing how the oil flows. It's all at about 650RPM, not sure what it was at when I revved it up, 1200 maybe. I know I know, I have blowby

Made a writeup on the 5th gear nut since I can't find one on the internet anywhere. http://mopar.mopar1973man.com/cummins/general/5th-gear/5th-gear.htm

Hi We have been working on the Cummins 12v fuel system and lift pump for over 14 months. We uncovered a lot of data, from hundreds of tests. This is article number one in a six part series. I hope you like it. Rob Parelli Here is the link http://torkteknology.com/news.php?newsid=5

Got a little courageous with the camera. Theres a smoke scene or 2 in there, along with wheel hop from where they sealed a crack in the road. I didn't know it smoked that much on initial take off. Shows what advanced timing does when it's not warmed up.I know I coulda washed it a little underneath and did some other things but I wanted you all to get the full experience I turned the camera around at the turnaround point, but then it became extremely boring, so I cut all that out. Any requests? Thinking of pointing it at the IP to watch it move, kinda think it would be a little boring though. I've been reluctant to doing anything with the camera until I finall…