adding CAC to existing dt466 motor

[hemivolvo]

Originally Posted by drcampbell

Boost pressure is down, but the temperature is probably down even more and the amount of air getting into the engine is probably up. (which is why I suggested using the Ideal Gas Law)

i dont really know what the ideal gas law is, dont know phisics, not to clear on how that helps me
i agree the boost is down,the temp is down, i think the volume of air is about the same just more dense due to it being cooler
as far as temp probe location im sure its hotter on the up side of turbo, but fact remains it went down after adding the CAC, no matter where i check it from, so it went down no matter where i test it, no way it went up
as far as the cooler size i got a catalog of charge air coolers and checked EVERY 466 cooler avail im very close to size used by all international trucks listed
i think this is a pretty simple problem with a simple awnser
i cant see melting the pistons unless i go over board with the fuel increase.witch is why i am looking for information on the early bosch rotary pump, im not going to just start turning screws and hope for the best.
ther must be some info on this pump somewhere ill keep checkin

[drcampbell]

Originally Posted by hemivolvo

i don't really know what the ideal gas law is, don't know physics, not too clear on how that helps me. ...

You can use the Ideal Gas Law, (look it up: Ideal gas law - Wikipedia, the free encyclopedia ) the air temperature, the air pressure and the displacement to calculate the mass of air going into each cylinder. When you know the mass of the air, you can calculate the maximum mass of fuel which can be injected before going over-stoichiometric.

You don't need to be concerned about lean air:fuel ratios; that's the normal operating mode of Diesel engines. They're controlled by fuel, not air, and always run lean. The air:fuel ratio may be more than 100:1 when idling or running lightly.

But the maximum amount of fuel is quite another thing. If you attempt to run on the rich side of stoichiometric, you'll convert fuel into smoke, greasy soot, coke and contaminated oil instead of torque & power.

Originally Posted by hemivolvo

i think this is a pretty simple problem with a simple answer ...

There is: Measure the engine's exhaust gas temperature. When it hits 1200° Fahrenheit, stop increasing fuel delivery. If it goes over 1200° Fahrenheit, the engine will melt.

Measuring the turbocharger's exhaust gas temperature will yield an indirect, variable and unreliable piece of information which will not enable you to protect the engine.

[hemivolvo]

Originally Posted by drcampbell

You can use the Ideal Gas Law, (look it up: Ideal gas law - Wikipedia, the free encyclopedia ) the air temperature, the air pressure and the displacement to calculate the mass of air going into each cylinder. When you know the mass of the air, you can calculate the maximum mass of fuel which can be injected before going over-stoichiometric.



There is: Measure the engine's exhaust gas temperature. When it hits 1200° Fahrenheit, stop increasing fuel delivery. If it goes over 1200° Fahrenheit, the engine will melt.

Measuring the turbocharger's exhaust gas temperature will yield an indirect, variable and unreliable piece of information which will not enable you to protect the engine.

all that math is very impressive ,i understand the principal but with out knowing fuel delivery exactly now, how would i ''calculate my increase''
im still just turning the screw with out KNOWING my delivery change
fuel rates on engine tag is listed as
210hp 99.9
220hp 203.9
am looking for inf on adj close to the 220 mark, dont know how sensetive this adj is ''how far to turn for first try''
as for the egt ill redrill and change it today and go out and test it again its very simple to do thanks for your time

[Evel486]

Wow. Lot's of information & a little misinformation.
Don't worry about the ideal gas law. This is a low tech very simple diesel engine. Stress DIESEL engine. There is no air/fuel ratio to worry about.
Your pyro pick-up is fine where it is. You need a relative temp so post turbo keep it below 1000 deg. Short spikes to 1100-1200 deg are acceptable but not for prolonged periods.
If you have a rotary pump (injector lines come off in a circle from the top of the pump) you have an Ambac Model 100 pump. You stated in an earlier post a diesel tech showed you the max fuel screw (if not, post it & I'll guide you) Turn this screw out 1/4 turn and road test. If you can't get your temp up under heavy load, turn it some more. If it comes up too quick, turn it back. Repeat until you are happy.
If you have an inline pump (injector lines come off in a straight line) you have a Bosch pump with RSV governor. If so, post this and I'll guide you through setting it up.

[fireguywtc]

Originally Posted by Evel486

Wow. Lot's of information & a little misinformation.
Don't worry about the ideal gas law. This is a low tech very simple diesel engine. Stress DIESEL engine. There is no air/fuel ratio to worry about.
Your pyro pick-up is fine where it is. You need a relative temp so post turbo keep it below 1000 deg. Short spikes to 1100-1200 deg are acceptable but not for prolonged periods.
If you have a rotary pump (injector lines come off in a circle from the top of the pump) you have an Ambac Model 100 pump. You stated in an earlier post a diesel tech showed you the max fuel screw (if not, post it & I'll guide you) Turn this screw out 1/4 turn and road test. If you can't get your temp up under heavy load, turn it some more. If it comes up too quick, turn it back. Repeat until you are happy.
If you have an inline pump (injector lines come off in a straight line) you have a Bosch pump with RSV governor. If so, post this and I'll guide you through setting it up.

Good post, this is something I would have suggested, but I do not have that much knowlege of this engine.

I think you are all on the right track. I just want to put it another way. Since you have cooler incoming air temps and more room to play with on the EGTs you can starting adding more fuel. Since your turbo operates off the expansive gases, you should be able to raise your boost closer to the 15 you want by adding fuel. Also watch your tailpipe, if you are starting to get more black smoke I would stop there and try to find a way to get more airflow, but I doubt you will have a problem with that. Once you find your happy medium I think you will be quite happy with the power and still have a reliable engine.

[hemivolvo]

OK i looked today and there are two 1/8 pipe plugs in manafold just above turbo i took one out and switched the sensor, took it out on hwy pushed it on more or less level and got close to 1100 but not quite, the only real hill around here is 50 mile round trip, didnt have time to go that far.my feeling still holds i was measuring in the wrong place but proved i only had 50 to 100 degree difference.

quote ''diesel tech showed you the max fuel screw (if not, post it & I'll guide you) Turn this screw out 1/4 turn and roadtest ''

the last two posts have been very helpful the tech told me to turn the screw in as toward the front to ritchen the mixture, i was thinking out made more sence please post proper direction and ill try to get it first part of the week
thank you so much for any info and ill get to it ASAP

[hemivolvo]

in response to evel486 yes i have the ambac model 100 pump, i did find some info last nite on this pump found some exploded views, no instruction on adj though. i took off the motor cover today and got a good look at pump i think the four bolt cover on top is where the ''screw'' is located comes with warning lable about changing mixture, it is not a cover but a box, the aneroid tube hooks to the rear of the box directly in front of the manual prime pump, do i remove tube and pull the box off to get to adj screw?
thank you for any advice also while i got you i want to turn up govenor approx 100 rpm as red line is listed at2600 and mostly i only get 2500, i believe this screw is the acorn nut at the back of pump at the very bottom does that acorn nut do the adj or does it come off and adj under the nut?
thanks again

[hemivolvo]

trying to post exploded view figure 2-3 shows box and adj screw but does not have aneroid tube dont want to take it off if i shouldnt thanks

[Evel486]

hemivolvo- I've been gone for a few days. It's been quite a few years since I've worked on a Model 100 so here goes.
The max fuel screw moves the camplate (see your illustration) You want to move the camplate forward to increase max fuel. If I recall correctly, turning the screw counter-clockwise will increase. Try about 1/4 turn to begin.
Your rated full load speed is 2600 rpm. To achieve this your high idle should be 3100 rpm. High idle is the rpm you get at wide open throttle in neutral. The screw for adjusting this is the one with the cap on it. The screw next to it without the cap is for low idle (adjust to 650 rpm)
If you have white or grey smoke at cold start up, you may have to adjust the timing. If so, post it and I'll give you instructions.
Adjust your fuel and road test. You can judge by your gauges whether to give it more or back it off. (You can also use your right foot to back it off)

[drcampbell]

Originally Posted by fireguywtc

... Also watch your tailpipe, if you are starting to get more black smoke I would stop there ...

Don't just stop there, back it off to the previous setting before you saw any black smoke.

Originally Posted by fireguywtc

... and try to find a way to get more airflow ...

There isn't much you can easily do to get more airflow. Any significant increase will require a bigger turbocharger.

[hemivolvo]

cool --- i have to work tommorow ill get on it wens morning, im getting from what you say to bring up my high idle first to 3100 in neutral, then adj mixture 1/4 turn and test, i should look for 1200 degrees on a good load [as in a hill i dont have to downshift for] would that be correct ?
again thank you for your time hopefully i wont have to go into the timing
once more the diagram does not show the aneroid tube i have, the box still just lifts off?
i cant wait to give it a try

[Evel486]

Turn up the fuel first, then set the high idle.

[drcampbell]

Originally Posted by hemivolvo

... i should look for 1200 degrees on a good load [as in a hill i don't have to downshift for] would that be correct ? ...

1200° Fahrenheit OR black smoke, whichever comes first.


(somebody please confirm or deny that 1200 is the right number - I'm not certain it is)

[Evel486]

1200F post turbo, 1400F pre turbo. But not for extended periods.

[hemivolvo]

OH BOY i tryed a 1/2 turn first this morning my no load high idle speed went to 2700, i can get a small puff of black smoke on free rev up to high idle, I drove it and WHAT a difference got up to 12 lbs boost from the 10 i had ,EGT went up to 1100 max pre turbo, tryed another 1/2 turn and it just feels amazing, shifts better and i can really feel and hear the difference,took it back up the steepest hill around and pushed it in second gear again ,, went up to 13 maybe 14 lbs boost and only hit 1150 max EGT. im really happy at this point should i go a loittle more and get what i can or leave it here i love the new power but am wondering about milage , ive got to go to an appointment now maybe ill try another 1/2 turn this afternoon i can always go back its easy to get to and simple to do thanks so much for all the advice