Bypassed the fdc, temp too high?

[wcolt45]

Bypassed the fdc the other day ,installed a Hewett pyro pre turbo and on the longest hill around here it will reach 1200*on a long pull,dont have a boost gauge,is that too hot?? I havent touched fuel adj,i have read make sure the rod doesnt turn while turning the nuts,as most have a allen or star head to hold the roll,mine has nothing to hold the roll,hate to put vise grigs on it to hold it but dont see any other way.To turn it down you go counter clockwise right ?how many flats should i go to start?

 

[gimpyrobb]

Nope 1200 is ok, but don't go over.

 

[Floridianson]

You are correct there is no star head or hex head to hold. That was incorrect post and I believe that person was adjusting the servo screw on the FDC.
When we increase main fuel we also increase the fuel at low end to. That is why we get lots of smoke on take off but should taper as rpm increase. If you want to get rid of that the the droop or smoke cam must be readjusted or turned down. The thing about temps is where is the reading comming from. I was always told to put the therm coupler one inch from the exhaust port on the head to get the true temp from the hottest cylinder. I have read that 1200 is fine on newer diesels and can be done all day. You would think we need to be a little more careful so depending on where you placed the coupler then when reaching 1200 you need to down shift if the rpm are dropping or let up on you foot. It's been said before these motors can be setup to full fuel but you still have control buy way of you foot.
The double nut and stud that stick out are not made of glass and the ones that might have broke the stud is because they did not use a thin wrench on the inside nut and turned both nuts with out knowing.
Without a boost gage then it is hard to know how much to go up or down on fuel if you are looking for a special number. I would put a boost gage on it then get back with some numbers. You could also read more adjust the low end fuel and keep the high end where it is and just take you foot out of it a little when the temps get to high.

 

[wcolt45]

I placed the probe in the location above the flange as Cranetruck recommends,toward the firewall.I have to say it starts much easier and idles much smoother when cold than before,and WOW much more power,it doesnt smoke at idle,only when you blip it a puff of black smoke will roll,1200* is as high as she"ll reach on a long hill ,hammer down.Maybe i lucked out then and wont have to mess with the fuel adj screw if 1200*isnt too hot,my lucky day.

 

[Floridianson]

I would think your good on the main fuel at full throttel it is the lower end that got increased to and if you read more you can turn that down and it wont smoke so much as there is not much air moving yet. Read up on the smoke cam droop screw.

 

[Billy Bobbed]

Do you have to bypass the fdc to get alot of smoke,or can you leave the fdc hooked up and keep turning the screw more and more.I have some smoke now just want more.

 

[gimpyrobb]

You can leave the fdc in place, but it has been known to leak fuel into the crankcase. I'd take it out of the loop.

 

[Billy Bobbed]

I was always told if its not broke leave it alone.I just hate messing with it,its hooked up and working I think.

 

[gimpyrobb]

Thats a good policy too.

 

[wcolt45]

Been reading on the smoke cam-droop screw issue and am not finding alot of info,if i do adjust the droop screw ,what am i after? it barely leaves a smoke trail,egt's are good=1200*on a long ,steep uphill pull,no smoke at idle,starts easier than ever,just need a little more clarification please.

 

[Floridianson]

You need a boost gage. Then we adjust the boost at 1600rpm and the boost at 2200. There realy is no need to have more fuel and no air at the lower rpm. Just waisting fuel. When we increase the main or bypass the FDC which I think everybody should do we have also increased the lower rpm range boost. You can have power and less smoke to on the no load. When the load starts to come in the boost will increase and then she might smoke but your at full rpm.

See if you can get 5lb and 12lb. or find out where your at now at both rpm ranges.

 

[wcolt45]

Thanks for the replies,will invest in a boost gauge and try to get it dialed in,in the mean time there is no harm in running it the way it is? just more fuel consumption?

 

[Floridianson]

I would think your ok so have fun.And your welcome.

 

[Billy Bobbed]

I'm at 13lbs of boost [c turbo]at 2200 now.

 

[Floridianson]

and your temps are good? How many turns did you put on the inside nut. Last one I did for a friend I put three full turns. He got a little scared and wanted me to turn it back one full turn. I did and he is still happy.

 

[Billy Bobbed]

I'm not in it to make more power,I'm just tired of the Ford,Dodges and Chevy diesel trucks around here showing me up with alot of smoke that they put out.

 

[Billy Bobbed]

and your temps are good?

I have never got over 1250.

 

[Floridianson]

Ok I see said the blind man. The funy thing is you can turn up on the nuts till the fuel coller has the spill port closed (full fuel) and they will run great but when the load starts (hills, large grades and loaded truck) the temps will rise fast boost will increase so you just have to let up on your foot. Camp fire not forest fire.

 

[Billy Bobbed]

I'm going to play with the screw tomorrow.

 

[Flyingvan911]

I'm at 13lbs of boost [c turbo]at 2200 now.

My deuce does the same thing. 13 psi at 2,200 rpm at about 52-53 mph. C turbo and LDS. I haven't touched my fuel yet. I really don't need to. The LDS has pleanty of power. I do plan to install a pyrometer.