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Discussion Starter #1
OK so I have read all the posts about tuning up your IP to get more HP...Not a problem and I even asked the IP guys to replace the tamper proof nuts with standard ones. So I'm all set!
A question I have is ...My motor is a a standard 80hp, my IP was off my old 110hp motor, I asked the IP guys to tune it to a 80hp specs when they were re-building it. So with the "" turn the screw inwards 1/4 to 3/4 turns for the stock 110hp engine or 1 to 1+1/2 turns for the 80hp engine"" I take it I'm tuning for an 80 hp engine?????
G Vavra
 

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If the IP was reset to 80hp, then you need to treat the whole engine as such. You would have been better off having the IP shop tune to the 110HP spec or even the 125HP.

Hindsight and all that!
 

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I never head of turning a 110 down to 80, It can be done but thats just dumb:confused:

I have tha 110IP and did one full turn it adds some good power but the EGT's increased pretty good and smokes like crazy.
 

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You can bring the smoke down and the acceleration EGT's by changing your gov spring tension.

This in effect reduces the amount of fuel you can get on acceleration, but does not effect max fuel.
 

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Discussion Starter #5
Snow mogg, I don't know if I agree with your dumb statement. I have been thru the whole motor replacement bit and I would rather start off with a IP and Motor that are both at factory specs before I start mucking with it!!
Thanks for the info DokaTD

G Vavra
 

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Hey KC, the spring tension you are talking about - didn't you start a thread on that some time ago? If so, maybe throw a link to it for us?

I turned up my IP and just went back and forth until the smoke v. power was in an acceptable compromise!
There is a little info here.

http://www.benzworld.org/forums/unimog/1604452-om352-injector-nozzle-replacement-3.html

Snow mog has a semi valid point as does the OP. The biggest issue I see with starting out at the 80HP setting is that there is a lot more to adding fuel the right way than just turning the big screw so to speak.

The more you increase the rack, you will find that the truck may be harder to start unless you add throttle. This is because the starting fuel delivery position is changed. Basically, the IP will not revert to full throttle when it is shut off like it should. So, unless your truck is warm, it just wont start unless you plow your foot into the throttle when you turn the key. Then, you really should make adjustments to the gov as well. In Snow mog's non turbo case, I would actually turn the gov spring counter clockwise 1-2 turns and the racks RPM changed slightly to compensate for any loss of max RPM to a point at least. This should reduce the amount of fuel delivered over the RPM prescribed fueling thus reducing smoke and EGT on acceleration but not causing loss of max fuel.

Clear as Mud Huh!!!!

Basically, in Kimos case I would have liked to have seen the IP start off at 110HP or better, but Dumb, not really. Just conservative! and potentially wise in certain situations.
 

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I don't think there was much internal difference between the 3 or 4 normally aspirated OM352's. After driving around with 80 HP, you'll probably regret not turning it up.
 

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The more you increase the rack, you will find that the truck may be harder to start unless you add throttle. This is because the starting fuel delivery position is changed. Basically, the IP will not revert to full throttle when it is shut off like it should.
Can you clarify this ?

The governor is what sets the rack position to full throttle (the tractor governor, at least). You're saying that messing with the max fueling will alter WHERE the governor sets the rack at -0- RPM ? ?
 

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Can you clarify this ?

The governor is what sets the rack position to full throttle (the tractor governor, at least). You're saying that messing with the max fueling will alter WHERE the governor sets the rack at -0- RPM ? ?
You got it. On the top of the gov you will see an access plug. This plug has a small adjustment screw. This screw sets the rpm at which the rack returns to full load which is required to start normally when cold.

As you adjust the rack, you change the relation of this screw and the plate/linkage it interfaces. You must compensate for this otherwise you will have to apply throttle to get the truck to start normally when cold.

All that said, I am defaulting to the truck gov design and I am not as familiar with the tractor gov.
 

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Interesting.

The tractor governor sets the IP pump to full fuel at zero RPM (the equivalent to full throttle). In other words, when you start your engine, the fuel is set to 100% until it fires off, then the governor drags it back to the idle setting. I wonder if the effect you described is the same on this type of governor ?

Anybody know ?

I have a Bosch book which details the tractor governor (RSV-type, I think, going from memory). I'll need to get it down and see if it mentions this or shows it on the mechanical schematic.
 

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Interesting.

The tractor governor sets the IP pump to full fuel at zero RPM (the equivalent to full throttle). In other words, when you start your engine, the fuel is set to 100% until it fires off, then the governor drags it back to the idle setting. I wonder if the effect you described is the same on this type of governor ?

Anybody know ?

I have a Bosch book which details the tractor governor (RSV-type, I think, going from memory). I'll need to get it down and see if it mentions this or shows it on the mechanical schematic.
Yes Tractor IP dose the exact same thing a KC explained earlyer, My truck became hard to start, I looked all over the thing thinking it was a air leak in the fuel system. Once I figured out I just have to push the accelerator pedal down to the floor I new it was something to do with the changed fuel settings. Big thanks KC now I think I know what I have to do to correct this hard start issue.

My engine stars hard, very smokey with large diesel particulate, Once its running it runs better than it did in the stock setting. Less surgeing more power. I dont want to loose the power increase on accel, you say max fuel will be changed to a higher RPM I dont realy want this, I only want it to start right again. So two turns counter clock here.
 

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Yes Tractor IP dose the exact same thing a KC explained earlyer, My truck became hard to start, I looked all over the thing thinking it was a air leak in the fuel system. Once I figured out I just have to push the accelerator pedal down to the floor I new it was something to do with the changed fuel settings. Big thanks KC now I think I know what I have to do to correct this hard start issue.

My engine stars hard, very smokey with large diesel particulate, Once its running it runs better than it did in the stock setting. Less surgeing more power. I dont want to loose the power increase on accel, you say max fuel will be changed to a higher RPM I dont realy want this, I only want it to start right again. So two turns counter clock here.

That's your gov spring tension nut (the one with the two slots). This will both decrease your max RPM attainable as well as the amount of fuel deliverd to accelerate. If you turn it counter clockwise, you will see less smoke on acceleration and minimal if any loss of accel power. At least on a non turbo.

The start fuel adjustment will be elsewhere but I don't know for sure where it is on the tractor gov.
 

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This link basically duplicates a lot of what is in the Bosch book on the RSV governor (the so-called tractor governor)...

Bosch RSV Governor Diagram | Ford Detroit CAT Diesel Engine Troubleshooting

Just a note, the RQV diagram at this link is lacking a few of the optional internals. Specifically those that set the pump to start without using the gas pedal.

The RQV in its most basic form requires you to apply full throttle to start the engine.

So it may be lacking some parts for the RSV as well.
 

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Assembly A and rack link #21 are responsible for the start fuel delivery. Notice the screw and nut on part #21. There is still another potential missing part in this diagram as well. but it includes parts that the link from Saurus did not include. BAsically, keep in mind that many Bosh publications only discuss the simplest version of the part and you must find more specialized docs to get the whole picture.
 

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Hello guys,

I don't want to go off topic here because this stuff is very interesting but I had a question that I needed answered or at least have people poke fun at it...

My "turbo" mechanic wants to remove my IP (well he already did and ran off with it) and replace the 8mm plungers with 10mm (!) in the effort to gain hp without adding a turbo.

He claims a turbo is not required to reach130-140hp. Just need the correct plungers. Not sure what else he wants to do to it.

I should add that he is a turbo and IP specialist. No joke.

My pump is the factory (Case mog) pump PES6A80.....and it has never been screwed with as all the factory fittings were still intact. (Well, he showed me).

I guess I just wanted some input from the people who are in the know. So I'm turning to you knowledgeable fellows out there.

Any input is welcome.

Cheers, and Merry Christmas to all.

Rolf
 

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First, can you get part numbers and such for the B's & P's.

Second, he is partially right. You certainly do not need a turbo to get 140HP. But, replacing B's & P's is not required. Your pump has enough fuel capability to go upwards of 200HP. You just can't get enough air in the engine to use it.

So, any IP work beyond basic tuning is not required and a waste of money.
 
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