Is an EGT gauge needed?

[Andyrv6av8r]

So I had my injection pump overhauled a while back by Diesel Care and Performance out of Tenessee and the HMMWV ran great ever since. A friend and I were talking about timing the pump so I decided to check mine. When I removed it to be sent out I had marked it's location and installed it in the same place. I could see the hash mark on the pump so I marked it on the cover. After the conversation, I cleaned the cover and found the hash mark on the cover under the paint. my pump mark was about 3/32" to the passenger's side of the fuel pump mark ( retarded ). So I loosened the pump and aligned the 2 hash marks. It still runs fine but I'm getting a very light, black smoke out of the tailpipe at normal speeds not just on hills. He says I need an EGT gauge to monitor my temps because it seems the pump was turned up so I don't toast an engine. I didn't tell them to turn it up at Diesel Care so I assumed just overhauled. What are your recommendations?

 

[simp5782]

DCP is a horrible company as us here locally have alot of issues with them. They tend to sell junk parts.

They probably turned it up as it's common to set it at a certain output pressure based on specs. We know the military detunes things. So what a civilian pump baseline would be is different than what the military had it at. This is common on the NHC250 pumps sitting 25 to 30psi below factory on rail pressure.

Egt gauge wouldn't be a bad idea if you wanted to. Or just get a thermal gun and drive around with your doghouse off and shoot the manifold while it's under load and normal driving just to get a base of what temps you are getting before being too worried.

 

[TOBASH]

EGT is never a bad idea, especially if someone turned up your IP as that generates more heat. It will tell you if you need to "detune".

Best,

T

 

[Retiredwarhorses]

EGT gauge is a turbo thing...not an NA thing.
ive been timing HMMWW’s for 35yrs...start at the scribe line and Advance from there, pay attention to engine noise and smoke color out exhaust. Advanced pump will make the motor “clacky” when cold.
A bit of black smoke is good, thats “burnt“ excess fuel, you don’t need to roll coal, just a whisp on mashing the accelerator pedal.

 

[Andyrv6av8r]

EGT gauge is a turbo thing...not an NA thing.
ive been timing HMMWW’s for 35yrs...start at the scribe line and Advance from there, pay attention to engine noise and smoke color out exhaust. Advanced pump will make the motor “clacky” when cold.
A bit of black smoke is good, thats “burnt“ excess fuel, you don’t need to roll coal, just a whisp on mashing the accelerator pedal.

Am I correct in saying that hash mark on the pump to the passenger side of cover mark is "retarded, not advanced"?

 

[HoveringHMMWV]

Following this thread with interest as I mounted my rebuilt IP just a gnat's hair to the driver's side of the timing mark. Truck also runs great and with no smoke. That includes starting and under load.
- HoveringHMMWV

 

[MattNC]

Thanks RWH, that was really helpful. I wondered as mine does what you said as I believe somewhere in its history at Fort Polk they turned it up a little and my Army friends have commented it has a bit more get up and go than normal. Mine does what you said, mash the throttle and you get a hint of black smoke that's gone quickly. Its worse when still not up to full temp.

 

[Retiredwarhorses]

Yes, advance to Drivers side, retard to passenger side. This is just for timing, it does not turn anything up, that’s done in a different way.

 

[Retiredwarhorses]

Thanks RWH, that was really helpful. I wondered as mine does what you said as I believe somewhere in its history at Fort Polk they turned it up a little and my Army friends have commented it has a bit more get up and go than normal. Mine does what you said, mash the throttle and you get a hint of black smoke that's gone quickly. Its worse when still not up to full temp.

remember, you cold start advance switch advances the pump timing when cold, once at 120deg, you will hear the motor get a bit quieter as it retards the pump timing.

 

[Andyrv6av8r]

remember, you cold start advance switch advances the pump timing when cold, once at 120deg, you will hear the motor get a bit quieter as it retards the pump timing.

What is the best way to check that the switch is working?