LorenS

NAPA stuff is Federal Mogul, right? Someone is playing games with me, then, because this AC Delco Professional branded unit is $98 and has the EXACT. SAME. PHOTOS! I switched back and forth about a dozen times looking for differences. https://www.rockauto.com/en/catalog/dodge,2001,ram+2500+pickup,5.9l+l6+diesel+turbocharged,1366602,suspension,track+bar,7500

@JAG1you used a RACOR setup, right? When I dug into their catalog I was nearly overwhelmed with all the options, like a kid at Christmas with a toy catalog. Then I was completely overwhelmed by the price, like the dad looking at the same toy catalog... So, I went Economy route for a pre-pump screen, the WIX mount and Donaldson spin on screen, and got NONE of the options I dreamed of! Do you have a good source for RACOR products? (If that's what you used)

Likely a Standard Motor Products product, so if one thinks they can't build a relay, probably shouldn't buy one in a different box. https://www.smpcorp.com/en/news/corporate-news/smp-named-2013-vendor-of-the-year-by-napa-under-hood-group Personally, it's exactly what I'd buy because I think they make good stuff if you buy the right product line.

I don't know which reviews you're viewing, but most of the bad reviews on one Amazon listing were from people who bought the wrong one, as if that has anything to do with the product itself. That 598 has a 3 year warranty, rated for 300A.

Guess that means that Bosch knows they go bad. By next weekend I should have the new one.

I agree, but even hammers can wear out. Over 330k miles, and I have no idea if it's ever been replaced. I also question the previous owners' maintenance regimen so it may have ingested some trash in its day. Hopefully I'll receive the new one in time for installation next weekend.

I could test it, but it doesn't act up all the time. Since the fuel temp reacts as the gauge moves, I think I the pressure must be representative - it may not be accurate or precise, but in the ballpark. $40 won't break the bank.

Just 3/8" to filter, and 1/2" filter to VP44 - 1/2" weren't popular when I bought the 3/8" lines.

So I read this article and would like some input before I spend $40 for a genuine Bosch replacement: https://mopar1973man.com/cummins/articles.html/24-valve-2nd-generation_50/51_engine/59_fuel/bosch-vp44-injection-pump-overflow-valve-r19/ Symptoms At idle in park I maintain a steady ~18 PSI. Driving it can drop to ~11 PSI, but sometimes rises to nearly 20, doesn't seem to be directly load related - sometimes it is low going up a hill like the filters are plugged, but then sometimes the pressure is HIGHER going up hill (gentle rollers). This can be within a couple miles, steady interstate travel. Some times on LONG, flat interstate stretches the pressure will rise and fall about every six to ten seconds (complete cycle, peak to peak). I parked my truck uphill for a couple of days while I traveled, when I came back the truck needed to crank a bit to start (assume fuel drained back to tank). No fuel leaks between VP44 and injector crossover tubes. No fuel leaks that I can find anywhere else. The couple of oil analyses I've had done came back clean, even after new injectors. This has been going on for quite some time, but MAY have become more noticeable (or started) when the draw straw was installed - however, there was so much crap caked around the factory sock that pressures were never very high to begin with and probably never even reached 14 PSI. Was neither better nor worse winter versus summer. Like an electrical gremlin, this isn't an all-the-time kind of problem, making testing the valve a bit of a crap shoot. Did this some with the stock steel lines and banjos, does it now with the 3/8" lines and no banjos. My fuel temps go UP when the pressure is HIGH! Fuel temps go DOWN when my pressure is LOW! To me, this is the biggest clue. Other Pertinent Info ISSPRO gauge and sender - yes, sender is on a 1/8" grease hose and not air brake line. There is also the snubber device (fixed orifice). Fuel filters have been changed numerous times in the time I've noticed this phenomenon (owned the truck a little over 3 years) Original (to me) lift pump was relocated to frame, then another Carter pump was installed, then a relay was installed to help out the ECM, then the DDRP was installed. I even 'hotwired' the pump relay direct (bypassed ECM) and went for a spin, same deal. My hypothesis I think the overflow valve is "sticky" - it doesn't open until pressure gets a little high, then blasts open and drops the pressure to around 10 PSI when it finally closes again. Would love some additional opinions on the matter.

@JHFIII glad you got it all figured out! Your under hood is like a surgery room or 5 Star Hotel compared to mine, just beautiful.

Back in 03 I drove people to the airport in E-350 15 passenger vans. Got great mileage, lower 20's every time. Of course they had highway gears, but I ran 75-80 MPH a lot of the time. A couple 1994-1995 vans had over 500k miles and just kept rocking! Alas, I have no answer about injector #7.

You say one battery went bad. I'd say it's fairly uncommon for one to go out and not affect the other. Was it just that battery's time, or did something abnormal cause it to go bad? If the alternator cooked it, why? Are the cables in great shape? Some guys report good cables, then find the cable is corroded under the insulation. Sounds like maybe the transfer case was a nightmare if it took four months to get it replaced, not sure how that and an electrical issue makes the "whole truck...a nightmare".

Looks like maybe ECM ground is a good place to start. https://mopar1973man.com/topic/7855-flashing-wait-to-start-light/?page=2 Are there any codes set?

I haven't tapped the pump, and dont plan to do so anytime soon. Level 3 is pretty fun until I fill up and I get to pay for that fun! Ha ha ha!

If I ever hit 325 HP I'll be shocked. Zero plans to join The 500 Club!

I used 3/8", but only because I bought all the fittings, etc., a few years ago before I knew everyone was going to 1/2". That filter head is tapped for 1/2". 3/8" has a cross sectional area 44% larger than 5/16" so I have no plans to change it. The whole setup has a low pressure drop, based on catalog data and my experience watching the VP fuel pressure gauge.

@Doubletrouble I have a frame mounted DDRP, this is what I installed for a screen to protect the lift pump.

I haven't tapped the pump, but do generally run around in level 3. I haven't tried level 2 with these settings, will likely do so on my next highway long haul. Do these numbers make sense for HY35 and stock reman injectors (50k miles)? As mentioned above, the truck is smoother, more responsive, boost at cruise has dropped from 5-7 down to 1-3 PSI! Haven't paid attention to IAT, but EGTs dropped some. I don't really see 2500 RPM very often, not sure I've seen 3k - certainly not unloaded.

I bumped my Low Load threshold to the max of 40%. Since I have stock injectors I figure that's got to be about the same as a lower load on bigger injectors. My engine sounds better and the fuel economy seems to have improved a lot. Low load cruising boost has dropped. Flat ground driving for me is engine load near 30%!

?? I thought you retarded timing because it's cold? Perhaps I misunderstand the +7. Is it 7 degrees WARMER, or just "7 degrees F"?

I understand the chart, I'm just pointing out that there is more than one way to raise the Cetane rating, and that chart is likely from "Method 1" at the refinery by removing less volatile hydrocarbons. I mean, there's a reason we don't burn #6 Fuel Oil despite energy of 152k BTU/gallon, but giant, slow piston speed marine engines do. I have noticed this, too. My grille inserts are installed! I truly believe that unless I was pulling a trailer through town in summer with the A/C on, I could leave them on all year. Question: how do we know when to drop the base timing, and not just increase the "Low PSI Timing Reduct"? Is that because it also affects the low PSI, high RPM operation?

I've been wondering about the why higher cetane diesel has fewer BTUs per pound. I decided to see if I could find something semi-scientific that made sense to me, and found this: https://www.gofurthergofs.com/Portals/0/Assets/Knowledge/Whitepapers/Diesel-Fuel-Cetane-Number.pdf Keep in mind they may make some money selling additive. An excerpt: "How can a higher cetane number be achieved? There are two ways to gain a higher cetane number. The first is to do it during the refining process. Refining a high cetane diesel fuel usually results in a fuel with a higher API gravity rating and a lower density. A low density fuel contains fewer BTUs and consequently provides less power to a diesel engine. A typical gravity for #2 diesel fuel is in the 32-34 range compared to a high-cetane fuel which typically has a gravity rating in the 36-38 range and more closely resembles a #1 diesel fuel. When a higher cetane number is gained through the refining process, it usually means the fuel contains fewer BTUs, resulting in less horsepower and poorer fuel economy. Another way to gain a higher cetane number… A higher cetane number can also be derived through the addition of cetane improver chemistry (2-ethyl hexyl nitrate). When cetane improver is added to a #2 diesel fuel, the result is a high-cetane-number fuel with more power and fuel efficiency than a similar fuel derived through the refining process. A side benefit is that #2 fuels usually cost less, too." My guess is that in refining they remove more wax, thus removing BTUs but that wax is some of the slower-burning fuel - and quicker to solidify in your fuel filter. When treating #2 with a Cetane improver the wax stays there to provide energy, but the fancy hexyl nitrates still allow for an easy start to the burn cycle.

Yes, many inquiring minds want to know! A long while back he told me to call him but then I got Wuhans and didn't feel like doing much of anything. Didn't remember that until I read your post, Dripley. Apparently he likes and trusts it a bit if he's now willing to part ways with the 40k mile HX35.

Agreed. Just wanted to point out (via the FSM) how much work it would be!

Depending on how worried you are about this, if you also plan to pull/change the injectors later you could pull them now before you crank the engine. While this may not be as effective as removing spark plugs, this will lower the compressive forces and thus the load on journal and other bearings. If you wanted to put a little engine oil or fogging spray in there, you could do that, too. Likely this is unnecessary, as Mopar1973Man has stated, but if I was pulling injectors anyway this is what I would do if the truck was where I needed it to be - like if I could push it to the shop, not out in a rainy pasture! If you REALLY want to wear belt AND suspenders, you could start on page 9-299 of the factory service manual and see if you can find a way to spin the oil pump. Looks like you'll have to get creative to pull a gear somewhere and hope you get it reinstalled correctly! If you plan to check the Killer Dowel Pin anyway, it may be worth it.