fuel pressure ?s

[Smokey73]

my '92 3/4ton has been acting up lately. runs rough at idle, low power and lots of white smoke. I suspected low fuel pressure and hooked up a test gauge before the fuel filter, it read no more than 5 psi. what should the pressure be?
p.s.
new filter, mechanical pump

 

[gatorman21218]

mine runs 4psi all day long.

 

[GenLightening]

About 4-7psi is what the stock pump puts out.

 

[gatorman21218]

sounds to me more like a timing or injection pump issue

 

[Smokey73]

if that's the case, then I guess it's not the lift pump

 

[Smokey73]

timing is set at 9 degrees advanced, and I did install reman injectors about 1500 miles ago, that was my next suspect. I am running about 30% wmo so the smoke ma be a little worse than it should be.

 

[GenLightening]

timing is set at 9 degrees advanced, and I did install reman injectors about 1500 miles ago, that was my next suspect. I am running about 30% wmo so the smoke ma be a little worse than it should be.

Did you set the timing after the injectors or before? If after, then there's the problem. If before, then we're still at square one. White smoke is usually a timing issue (unless you just lost a head gasket) and WMO at that ratio shouldn't cause noticable smoke.

 

[Smokey73]

timing was set when i put the injectors in. it ran good for a while, then started all this. I almost positive that the problem is with the fuel system. The smoke is a heavy white fuel smoke.

 

[Smokey73]

also...
after I changed the fuel filter, it ran like it's supposed to for about 20 minutes of driving around the pasture, then went back to clanging and clattering and blowing smoke.

 

[Late_99_psd]

Maybe you got a bad batch of fuel. Cut open your old filter and see what it looks like.

 

[trapper]

when mine done that the IP took a dump

 

[Smokey73]

I finally got around the fooling with this thing again. I had an old pump laying around that i knew was working when i pulled it off. I put it on and that truck ran great. No smoke, started good and idled smooth. At first, the only problem i had was that I couldn't get the timing any better than about 6*. I put it all to gether an took off down the road, I made it about 15 miles and it fell on it's face. I pulled over and befor I could get it stopped good it died and that was it. I called someone to bring me my big trailer and pick me up. It took about an hour for him to get there. By the time he showed up, the truck started on its own and ran fine again, I didn't take any chances and loaded it up anyways. My next step is buying a new pump i suppose.

 

[Smokey73]

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