Cleaned fuel pickup, no more smoke!

[k2diesel]

OK, go figure. My 1st gen had some smoking issues. Did some basic bombs, i. e. , 16 cm hsg,afe7,pdr190's,4"exh,mild pump/timing tweaks. No matter what I tried with afc starwheel tension, backing off full power screw etc. , I just couldn't make it not smoke. And I don't mean gettin on the go pedal hard smoke,(I like that) I mean just barely feathering the pedal to accelerate and she's smoking moderately. Just didn't seem right. Also, power seemed low as well. Could make ok boost 15-18 psi by turning fuel screw more, but even more smoke as well. Checked intercooler for leaks, changed out the fuel filter twice, new lift pump, air filter, all the usual stuff. Then I decided to check for fuel system restriction as per the fsm. T'd in a vacuum gauge before the lift pump, duct taped it to the windshield and went for a drive. According to the fsm, maximum reading should be 3. 75"hg. Depending on load, I was reading as high as 10"hg! So I pulled the fuel sender/pickup unit from the tank. There are 2 filter screens, an inner, and outer. The outer screen is designed to filter the fuel the majority of the time. When the fuel level gets low, or the tank is on an incline, a foot valve drops causing the inner screen to filter fuel from within the fuel reservoir on the unit. Well , some knucklehead had evidently decided that it was not a good thing for that foot valve float to do its thing, and screwed it to the outer screen assembly, causing all the fuel all the time to be drawn through the smaller inner screen, which lays flat and naturally accumulates more sediment than the outer circumfrential screen. The inner screen was all plugged up. No wonder I was pulling 10"hg! So I quickly cleaned it up in the solvent tank, removed the offending screw, replaced the unit and went for a drive. Lo and behold, good power, good boost #'s NO smoke pull up through mid- range, and only light smoke top end mashing it! Oh yah, vacuum gauge now maxed out at 3"hg! Moral of the story... . them pickup filters, clean em up! K2

 

[tugboatphil]

K2,



I've been wanting to get inside my tank since last summer. My problem is my fuel level sensor. While you had it apart, did you get a lot of sediment off the bottom of the tank?

 

[Philip]

Good job of troubleshooting.

 

[k2diesel]

K2,



I've been wanting to get inside my tank since last summer. My problem is my fuel level sensor. While you had it apart, did you get a lot of sediment off the bottom of the tank?

Phil, Surprisingly, not much sediment at all in the tank. I'm painting the bed, so I removed it to access the pickup unit. The tank was about 1/4 full and there did not appear to be any mung at the bottom nor floating around in the fuel. So I gloved up with nitrile gauntlet gloves, grabbed a few CLEAN red rags, and swept/wiped the bottom of the tank. The rags came out amazingly clean. Kenny

 

[BushWakr - RIP]

k2,,,,that's a good tip for the guys... . most of us don't go "that deep" into the truck unless it's absolutely required..... you are obviously NOT afraid of a little work, so... .

10 BONUS RWHP !!!!! good on ya dude...



pb... .

 

[DValentine]

Pulled mine out while I was down. Didn't find any nasties, but thought it was a funky set up. I replaced the rubber bung around the filler neck. DC had it in stock. Mine was falling apart.



What kind of boost numbers are you seeing K2?



Dave

 

[k2diesel]

Pulled mine out while I was down. Didn't find any nasties, but thought it was a funky set up. I replaced the rubber bung around the filler neck. DC had it in stock. Mine was falling apart.



What kind of boost numbers are you seeing K2?



Dave

DValentine, sorry for the delay, I've been away from a computer for a while. I was getting about 18 psi boost fully mashed, although my bed is off right now to paint, so there's less load. Just installed a 2001 HX35 compressor side, gained about 2 psi, sounds/feels easier breathing, cools down for shutoff quicker. Couldn't resist cranking the full power screw 1/2 a turn, runs pretty strong now with about 24 lbs. boost, however, now my cooldown time is longer again. Kinda squirrely without the bed too! I think my next experiment will be trying the 12 cm wastegated hot side. I want to make low end torque so if I have to sacrifice some upper end breathing, I'm ok with that. In any case, finding and fixing my altered and plugged up filter screens was the one thing that finally made my truck run "right". Good Luck ! K2

 

[DValentine]

Thanks for the reply. I am now saving pennys for a better turbo. Kinda interested in what swankmetal comes up with on his twins.



Dave