Bosch CP4 Not As Reliable As CP3?
If the VM Motori 3.0L V-6 diesel engine you wrote about in “Inside the VM Motori 3.0L V-6 Diesel Engine” (Aug. ’12) utilizes the Bosch CP4.2 high-pressure fuel pump, it will prove to be a reliability disaster. Bosch’s latest injection pump has not had a great track record in the ’11 to ’12 Fords and Chevys (in CP4.1 form) and in the ’09 to ’12 Volkswagen TDI 2.0L vehicles (in CP4.2 form).
We’ve heard some reports of difficulties with these Bosch CP4 pumps—an attribute that we had previously chalked up to the increased injection pressures and the implementation of the new pump architecture in our marketplace. In general, the Bosch CP3 common-rail injection pump has proven to be bulletproof, while the lower-cost CP4 pump may still have some growing pains to work through. When we asked our industry expert about the differences in the two pumps, we were told, “When a CP3 pump fails, it sends metal back to the fuel tanks. When a CP4 pump fails, it sends metal into the injectors.” So both pumps can fail, it just seems that the collateral damage can be higher with the CP4-based systems.
There’s Always a But…
You’ve got a great magazine. It’s the best on the market, bar none! But in the “Maximum Flow” article (Sept. ’12) on page 144, you show a picture where you wrote about TIG-welding a stainless-steel tube. The proper terminology to use when referring to slag in the welding process is “spatter”—not “splatter.” Splatter is what happens to bugs on the windshield.
Craig Ring Certified Welding Inspector
Morgan City, Louisiana
I’m a UTI student who loves your magazine and am wondering if you could help me with a picture I need for a tattoo. I would like an image of a Cummins 12-valve from the flywheel, but looking down at the engine with all major components. I haven’t been able to find one online.
We couldn’t find the exact angle you’re looking for in our archives, but when we do come across the image you’re looking for, we’ll post it on DieselPowerMag.com.
Theoretical vs. Applied Diesel
I have to begin my letter by saying I’m a 24-year-old addict of Diesel Power. I get in big trouble for being antisocial and spending too much time with your magazine. My addiction to diesels started from my love of Volkswagens. Now that I’m older (and wiser), I graduated to a Ram 2500 with a 5.9L Cummins. Sadly, its transmission went kablooey, and I’ve been unable to afford to repair it because I work at an oil change shop.
I’m very interested in ripping diesels apart and rebuilding them, but I also thrive on data. Can you guys point me in the right direction on how I can get experience with diesels as a whole, ’cause I’m a statistics junkie?
Elmvale, Ontario, Canada
It sounds like you’d benefit from getting a job at a diesel truck repair place. Full-service shops can always use an extra hand, and perhaps they’ll let you work on rebuilding your transmission afterhours. Look for a shop with a good reference library of technical manuals, and it’d be a plus if it catered to customers with diesel Dodge Rams.
Old-Body-Style B.S., and Our Model-Year Error
If it weren’t for your magazine, I probably wouldn’t spend nearly as much time reading as I do. I usually pour through each issue cover to cover within days. I love it. Anyway, I just received the Sept. ’12 issue and noticed that on page 84 you listed Rocky Horn’s ’97 Ford F-350 as an ’07. Although I wish they still made trucks like they used to, they don’t. Come on, we all know that truck is a ’97.
I’m a Duramax guy at heart, but I love reading the stories about all three brands. I think no matter which truck you think is best, we all need to stick together to better the diesel community. Keep up the good work.
Unfortunately, we made that error when switching the magazine layout around at the last minute. Like you, we know Rocky’s common-rail Cummins, old-body-style (OBS) Ford is no ’07. Rocky himself actually called us the minute the September issue hit his mailbox. For the record, his F-350 is a true Ford, with a 5.9L Cummins engine, and it is a ’97—not an ’07.
To all our readers, we thank you for your comments and compliments. Keep those emails and letters coming. Write to: Diesel Power, 831 S. Douglas St., El Segundo, CA 90245, or email us at firstname.lastname@example.org.