FrmrPowerjoke

Ok, first post, so take it easy on me fellas. Sorry this is so long, but i wanted to provide all details up front and i don't wanna buy the wrong truck again.

I am hopefully a day away from selling my money pit OBS powerstroke. No mods, just fuel lines, CPS's, New trans, new glow plugs, new tires, and the reason it's not going away till tomorrow is a new #7 injector(came out to over a dollar a mile in maintenance). I got tired of borrowing my buddy's '97 12 valve when my truck was in the shop.
Assuming my truck goes away i will be traveling to Cogan Station, Pa to pick up a "new to me" 2007 QC LB DRW 3500 G56 Dark Blue Big Horn with 225K miles. Has had clutch replaced with new single disc, 60 hp injectors were done at some point, 5" straight pipe exhaust. First owner registered as a commercial vehicle. It's on second owner now. If anyone knows the guy selling it and can vouch speak up please. The truck appears to be very well taken care of, the only leak i could find was on the bottom of the front diff. It appeared to be very very slow as there were no oil spots on his driveway, and he is replacing the gasket before i buy. It has full service records on carfax from before he bought it. He just did all the front end wear parts, the breaks, and new tires. He also has an immaculate 2nd gen VERY built 12V flatbed that he is selling along with his 24V pulling truck and excavator so i believe his "i lost my job and need some cash" story. I don't think he is unloading it because it's a lemon. I checked the exhaust on cold start, no white smoke, fired up immediately with no injector lag or whatever. No black smoke when revving with no load. Front end is tight as can be. I hit some washboard action at 60 mph and no death wobble. Haven't done blow-by oil cap check yet because I'm taking it to a mechanic before i buy and getting him to do a compression test. FIRST QUESTION: Is there any other specific stuff that i need to make sure the mechanic tests?

SECOND QUESTION: #1 goal is NOT more horsepower or torque(i don't mind a little, but more power = more broken stuff). This rig will mainly be used to tow a 10K horse trailer and i don't want my wife to accidentally put our horses through to back door of the trailer if she side-steps the clutch, plus horses don't like Soot. I don't have unlimited funds, but i want to get 500k miles out of this motor. I've read about monotherm pistons and all kinds of other dream sheet builds. I plan on putting an Air Dog 150 set up in. Is there anything else i can do to keep this thing from catastrophically failing and maybe get a little better fuel mileage? My budget is about $2,000 after the purchase price of the truck. Also, does the Air Dog play well with biodiesel?
Thanks for reading my novel, any and all replies are greatly appreciated.

Hintonc393

I would check the fluids in the axles and the transmission for metal. It is normal to see a little on all three magnetic plugs. 07 is not a bad year, seems like they eat injectors a little more than other years, compression test is a good thing but it will be a lot of labor. He will have to pull all of the injectors, connector tubes, fuel lines and valve cover. Another option is to get a graphing scanner and use the amp clamp around the positive lead to the starter, unplug the crank and cam sensors to crank the engine with out it firing and watch the amp graph to see that all the spikes are even. Its not as accurate but keeps you from putting money in a truck that is not yours yet.

The problem areas on a 07 are the about the same as all of the other third gen trucks, the front end sucks, seats foam is cheep, A/C is a little on the weak side, the front axle has no locking hubs so you drive it all the time the wheels are rolling.


Have your mechanic check the front hubs and ball joints when he has it. They are known problems. The hubs will cost you about $300 for parts the ball joints are about the same per side depending on what you buy, they can go up to $800.

As far as your upgrades, most on here will tell you to get a smarty jr. you can gain about a mile to a mile and a half per gallon on the fuel economy setting. That will work well with your 60 hp injectors. If it was mine I would look into a cam, with your injectors and the cam you could make some major gains in safe hp and fuel economy. Most cams are around $500-600 bucks but the labor to install is what gets you.

Hintonc393

The air dog is not bad but if you are not going after major HP you don't really need it. The in tank pumps seem to be much better than the old filter mounted pumps. I would get a 2 micron filter setup.

The number one killer of the common rail engines is injector failures melting pistons. An EGT gauge can save you some big money if you pay attention to it.

Oh and if you are after high mileage stay away from the cold air intakes, they use high flowing filters that do let more small dirt into the engine. The stock system is good to 400 hp so you dont need the air flow anyway.

Filters you need are
Donaldson ELF7349 oil this is a 15 micron filter
Baldwin PF7977 fuel this is a 5 micron filter for the stock system
I use the wix 49946 but Amsoil makes a great air filter for our trucks.

FrmrPowerjoke

Thanks for the quick response. I've never heard of that method of testing compression. It sounds much simpler. Is it just testing to see how hard the starter is working to stroke each cylinder? Compare the amperage spikes? I don't like to do anything unless i know exactly how and why it works. So you're saying just run an extra in-line filter between the tank and the lift pump?
Would the injector stuck open indication would be skyrocketing EGT's? Does anyone make a gauge with an audible alarm at a predetermined setpoint?
What's your opinion on the Amsoil filter Bypass kit? My buddy is a dealer and swears by it.

Hintonc393

Yep, the amperage drawn by the starter is a indication of compression. Like I said it is just a general idea of how the high the compression is versus other cylinders but it should show if there is a low one.

A lot of guys on here are running a add on filter system like my XX-fuel filter. XX-fuel is no longer around but you can make your own or buy one like I did. The filters that I run are the Donaldson P551313 and the P550847 plus the baldwin P7977 in the stock filter housing. Your truck has the lift pump in the tank just like normal.

The EGTs jumping way up will indicate a cylinder getting way to much fuel, with a common rail the injector is supplied with fuel all the time so it is up to the injector to control how much is injected every time a power stroke comes around. If the injector hangs open then it is free to inject with out stopping.

The bypass filtration is great, the filters are a little on the expensive side. Anything that adds filtration is not a bad thing. Check out http://oilchargesystems.com/

Hintonc393

Oh, and the EGT gauge will only really show a hung injector if the probe is in the right spot. Some guys mount them in the manifold just above the turbo but that will only give you an average of three cylinders. A company called Westach has a gauge that will show two probes on one gauge, I have been thinking about putting three in to show EGTs for every cylinder. Its kinda over kill but it would make my feel better.

Hintonc393

Don't worry about getting beat up for asking questions around here this forum is not like most. No one knows all this stuff when they were born so at some point we all have to learn. We have a great bunch of guys here, you can ask questions all you want with out worrying about getting picked on.

FrmrPowerjoke

Here is a link to the youtube video of the blow-by test i had the guy send me.
http://www.youtube.com/watch?v=Hl0fP...ature=youtu.be
Does everything look/sound good to you guys?

jhenson

Sounds normal to me. If that engine had blow-by it would normally blow the fill cap out of the hole once it's unscrewed.

Hintonc393

That rattle that you hear in the video can be fixed by retiming the CP3.

FrmrPowerjoke

I went ahead and got the smarty jr POD. Man, that thing is nice. I was wondering if i could play with the timing on that to fix the CP-3 issue??? I know it's a long shot, but i figured i'd ask. Here is the best link that i could find to the mechanical fix.
http://www.cumminsforum.com/forum/3r...y-cp3-fix.html
I also purchased the 2 micron remote mount fuel filter kit from glacier diesel. Any opinions??

Shorts

The GDP is a good kit. I've been happy with mine. Easy install as well.

soulezoo

cp3 noise is mechanical. Smarty jr can't help that.