Patrick Airdo

I can't get my fuel pressure up at all. Truck blows no smoke. I've installed fuel pin, 3200 gov spring. Smoke screw flush with jam nut. Start wheel clockwise two turns. I only have like 3/8 of power screw left with the jam nut on. Hasn't ran away yet. thought my lift pump was bad so I installed a new mechanical lift pump. From what I understand guys can get there trucks to smoke on stock injectors. Truck only seem to blow white smoke when at WOT. I'm starting to think my Ve pump is not working correctly. I have no gauges. What could be my problem?

Extra info on the truck.
91 non intercooler. 350,000 miles. Ve pump hasnt been messed with before I got my hands on it. It's a piece.

oliver foster

Getting a good running NON intercooled truck to smoke is easy. The stock injectors are actually quite large.

Blindly tuning a 12Vs with no gauges can give lack luster results. You can't not see what you modifications are doing, and you can ruin your motor with too much fuel and high temps.

Start by getting some gauges. It is not THE problem, but solving the problem without them will be hard.

Blowing white smoke tends to be a signs of struggling for fuel, OR burning coolant...

Welcome to DTR.

Patrick Airdo

shouldn't I be getting insane amounts of black smoke? That's not my goal but from what I've done to the pump shouldnt it be over kill? I don't seem to be loosing any coolant and I obviously have a fueling problem... Starting to look like a failing IP.

oliver foster

Before you condemn a expensive part like a injection pump.
I would get gauges, check throttle indexing, the throttle cable is getting full throw, fuel pressure after the lift pump, make sure if you have a plugged fuel filter, maybe air in the line and tons of other simple and cheap fixes.

Or just go for replacing the most expensive part on the motor blindly 'cause it just feels right.....

Since the pump was messed with before you got it, it could easily be tuned way out of wack. I have seen stock motors / pumps where the fuel screw collar was almost bottomed out from the factory.
IIRC I could only get 2/3rds of a turn on my fuel screw on my '91.0 motor before the safety collar bottomed out.
I pulled the fuel screw, removed the collar and tuned it to run awesome, using my GAUGES to guide me every step of the way.

Patrick Airdo

Just did filters and fluids 50 miles ago. Truck revs up all the way as I do it from the IP and doesn't sound to be choking out from air or fuel. Like it looks and sounds fine but now it does white smoke alot since I've changed star wheel. IP had all protective caps on it when I bought it. I do wanna get gauges, is there any test I can do to determine what's causing this before I spend all that money on gauges? Also what gauges do I need? Fuel pressure? Installed after fuel filter? Pyro and boost? Those seem to be the only gauges i woulde need. If I figure out I have good fuel pressure to my ip, how will I determine what to do next?

BHD

Welcome to the DTR.

Manifold pressure and Exhaust temp gauge. Put the exhaust temp gauge in the the manifold not in the downpipe.

My '90 W250 didn't smoke much either when I turned the fuel screw and star wheel and smoke screw, but it sure got hot pre-turbo.

Throttle indexing was off, timing was off, manifold plenum gasket was blown on the back side by the cab, and had crappy injectors.

These trucks are really easy to turn up or screw up and that depends on the brains behind the tools. If yours was molested before you got it, who knows what happened.

Get some gauges and see what is going on, otherwise you are just shooting in the dark.

maybe368

I would listen to these guys if I were you, they know of which they speak. Even a crumby, bad smelling, not running right 6bt is worth respecting and salvaging. You say it hasn't run away, yet, but are you prepared to kill it if it does? You say that it is your first diesel, so if you are going to mess with the pump, you need to be a like a boy scout, prepared. Welcome to this forum full of really smart and wise 1st genners...Mark

Patrick Airdo

QUOTE

I was fully prepared for a run away with a 2x6 , and I ordered a glow shift 3 gauge kit yesterday. Once I get my data il report back to here.