01 f550 missing

[robp823]

Have an 01 f550.Its hard to get started and while trying to start just smokes white and smells like raw fuel.Once its started it misses bad.Once it hits operating temp the miss goes away and it hazes white at idle.When you romp on it in park it billows white/black smoke more white then clears as it goes through the rpm range.Still stinks like raw fuel.cold cylinder contribution test says 3 and 8 same hot.I was going to do a fuel pressure test for the hell of it.Some reason i thought 99-03 had a shrader valve on the filter housing ,guess i was wrong.Over 200,000 on the clock.My senses tell me just might be time for some injectors also thinking it could just be bad o-rings.Thoughts please??

[Bruce Amacker]

I think I'd do a compression test before putting injectors in it. Check the FP at the right head, there's an 1/8" NPT square head plug there for FP on the upper inner surface. Look at MFDES and Perdels at a hot idle in scan data and tell us what they are.

 

Check glow plug amperage for the cold start problem, should be 195 tapering off to 125 after 30 seconds.

 

Lotsa dusted motors in 7.3s.....

 

 

Good Luck!

 

[mchan68]

GASOLINE???

[Jim Warman]

I'd be considering injectors, too... But like Bruce says, you'll want to do some investigating to be sure this engine isn't a money pit.

 

I might add a visual inspection of the turbo and intake duct (how many of the stock air filters I've seen with improperly installed lids.....) and probably a crankcase pressure test, too. Not very intrusive and quick to perform - be aware that if you have low pressure and non-contributing cylinders that crankcase pressure might be low BECAUSE of the non-contributing cylinders.

 

Even if you can get away with just O-rings, seems to me 7.3 injectors are now cheap enough to be a good insurance call. FWIW, I haven't had much luck with FQR injectors.

[robp823]

Sorry i didnt include that Per dels @ hot idle for cylinder 3 were 2% and cylinder 8 were 4%.I know i should prolly do a compresion test.I was thinking of grabbing some standyne and running a bottle through it.

[Alex Bruene]

Before I call a set of injectors on a 7.3, I always have a good look at the oil pan condition. If it's rotted and ready to be changed, and factoring the cost of the pan and a set of injectors, you can replace the engine for not too much more moolah. Keeping in mind that my (former) dealer would sell an engine for between $800 and $1000 over dead cost, so that made for a pretty competitive engine price. I don't know what to expect from my new dealer. I'll cross that bridge when I get there.

[mchan68]

Before I call a set of injectors on a 7.3, I always have a good look at the oil pan condition. If it's rotted and ready to be changed, and factoring the cost of the pan and a set of injectors, you can replace the engine for not too much more moolah. Keeping in mind that my (former) dealer would sell an engine for between $800 and $1000 over dead cost, so that made for a pretty competitive engine price. I don't know what to expect from my new dealer. I'll cross that bridge when I get there.

Funny you mention that. There was just such a truck in last week that poo-pooed his 4R100 tranny. This unit had about 400 and change thousand on the ticker, and the guy opted to have the tranny replaced with an aftermarket rebuilt unit too, along with an aftermarket rebuilt IDM. This truck too, had a rotted oil pan, not to mention a dead miss from at least one, if not two cylinders after the said repair. I'm only so glad I wasn't involved in that repair in any way.