New guy here!

[dave186]

Ok guys I just bought my first diesel, a year or so ago i would have told you i would never own one but with the price of gas the more efficient diesel made sense for a work truck. I ended up with a 93 7.3 IDI, ZF5, its a regular cab with an 8' service bed. 248,000 miles on the odometer and i have no clue whats been done to it over the years.

I have one concern though, it blows a ton of black smoke if i hammer the throttle. ive been around these trucks before and i know they dont even let out a puff in stock form. this one will lay down a cloud for miles if i wanted too. I looked at the IP and it says its been rebuilt by a stanadyne service center, and has little blue paint pen marks on all the bolts. the injector return lines also look brand new. the truck runs great otherwise, starts easy, no blue or white smoke when cold just wondering if something is wrong that im overlooking. i replaced the air filter since it was nasty and will do the fuel filter this week, but would that have anything to do with it?

TIA,
Dave

 

[SKimballC]

Lugging it will make smoke and they WILL roll coal in stock form. Install a pyro and maybe turn the fuel down a flat or two.

OK, newb, where do you live?

 

[Mr_Roboto]

No it shouldn't blow "a ton of black smoke" in stock form. Most likely the max fuel screw was turned up while installing the IP. The thought being that if some fuel is good, that more must be better.

The danger is that with excessive fuel comes higher exhaust gas temps, which can melt your pistons. A short blip of the throttle won't do it, but a long pull at WOT while overfueling can.

I would suggest turning down your max fuel screw to see if that remedies the problem. Someone will chime in with instructions, I don't fool with such things as max fuel rate (as most want to turn up not down).

We will also need to know if your engine is turbo or naturally aspirated.

 

[SKimballC]

A 15 year old, 250K truck with no known work but an at-some-point rebuilt IP doesn't exactly inspire visions of crystal clear exhaust, but as Roboto reiterated try turning the fuel down. Here's how, courtesy of Zigg. http://members.shaw.ca/k2pilot/Injection pump adjustment article.htm

 

[Agnem]

Either way, you need a pyrometer. Get one installed if it doesn't have it. I fear for the beast if the previous owner turned it up without one.... Turning the screw back is a good idea if a bunch of different people drive the truck, but if that is not the case, you can just train yourself to take your foot out of it, and accomplish the same thing.

 

[dave186]

I havent been lugging it, it will smoke at 3000 rpm if i lay into it. im the only one that will be driving it and i have just been keeping my foot out of it and keeping an eye on the tailpipe going up hills and stuff.

I have a suspicion that the engine has had some work done at some point, its just too clean for this many miles. snooping around a bit i have found that it has all new rear brakes, new master cylinder, a new AC pump, new condensor and new clutch master and slave cylinders. I know the place i bought it didnt do this stuff to it.

I think i have a pyro gauce at work, i will see what i can do. i did some searching and it looks like most guys are putting them in the exhaust pipe. why not the the manifold?

 

[dave186]

i forgot to mention its NA, no turbo.

 

[Dsl_Dog_Treat]

i did some searching and it looks like most guys are putting them in the exhaust pipe. why not the the manifold?

You can drill and tap the pyro probe into the manifold as that is the most ideal location for monitoring engine temps.
Closer the better to the heat source.
On my 90, I dropped the probe in 3" below the manifold on the drivers side and get a pretty good reading and was an easier install for me.

From what you're describing, it sounds like the PO has turned up the pump so that pyro install is a wise move to see where it's at.

Welcome to OB!

 

[dave186]

thats where i will put it when i get around to it. I am pretty sure that the pump has to be turned up.

one more small thing im wondering about is the water temp light on the dash, the one below the wait to start light. its always on, never turns off. what sensor controls it? the temp gauge appears to work about as well as you would expect these ford gauges to work.

 

[SKimballC]

The light under the 'wait to start' on your '93 is 'water in fuel' isn't it, not water temp?

 

[dave186]

i mean the water temp one, not water in fuel. it is under the wait to start, maybe not directly but it is under it.

 

[dave186]

Ok, I looked at it today and is ENGINE TEMP and it is right below the wait to start. any ideas? also is there a chilton or haynes manual that covers these diesels?

 

[subway]

there are two sensors for the temp warning light and one for the temp gage. they are both located on the front driver side area but i cant remember which is which.

sounds like the warning light sensor shorted on ya