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Discussion Starter #1
Recently I bought a 1991 Bluebird Schoolbus with a 5.9 cummins. We drove it home from Oklahoma City and it would not get above 55 mph and was a dog when it came to any hills. It is strong at low speed in the city and what not. From what I have searched and heard there is something I need to adjust within the injection pump to remove the govenor? What injection pump does this engine have? I need some help on what to do to remove the govenor or simply raise it higher. Also, I have noticed the turbo does not have a wastegate, what is that about? I am sorry, I am totally new to diesel engines.

Is there any tutorials that show what can be done to waken this engine up a little. Im not looking for a hot rod, just a little more than what it has already.

Please don't flame on me, I have tried searching through threads and what not but my inexperience leaves me still asking questions. Thanks in advance
 

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School bus.....
Planing to convert to a party bus/ tailgate machine?
The first mod you are looking for is the GOV spring.
If you post up a pic of the injection pump, someone on here will chime in with what it is. Also, if you can get to the enginge data plate, and list what CPL it is, that is usefull information as well.
Most likely you have a Bosch VE pump, or an inline pump (7100)
If the injector lines are in a row on the top, it is the 7100 "inline" pump
If the injector lines comr off the back of the pump, most likely it is a ve "Rotary" pump.
 

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Discussion Starter #3
The plans are a party/roadtrip bus for the summer. Something we can haul are bikes in the back and camp out in.

I appreciate the help. Where is the engine data plate going to be located so I can get the numbers next time I go to my shop. I will also check what the pump looks like next time I'm up there too.
 

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The data plate should be on the front gearcase cover.
Front of the engine, drivers side, in front of the injection pump.
 

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On some diesel buses, especailly school bus, they had a throttle linkage stop in addition to the injection pump governor spring. May be at throttle pedal or at linkage on top front of injection pump. Just disco-ing that can get a bunch more top end. May need to move throttle cable connection to the hole closest to pump on pump's throttle lever too.
 

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Also look at the turbo. As for the Dodge applications, they had up to a 21 cm housing that would never spool up and they had poor response as a result.

In short, more air and fuel are good if you plan on monitoring them through guages. A turbo upgrade so it will spool faster and to take advantage of the increase volume.

Usually the first thing is the governor spring so the motor can turn more RPMs. Then the next easiest is to turn up the fuel on the pump (again guages installed before this is done). Then turbo swap before injector upgrade (at least my line of thinking).

If you get it turned up, smoke the tires and post a video!!!
 

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you probably need faster gearing, any school bus I have ever been in didnt need any more power but at full throttle all you could get was 100km/h (canadian) or highway speed.
 

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Don't forget to install a pyro if it doesn't have one already! Real easy to have a meltdown with that much weight under load.
 

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The plans are a party/roadtrip bus for the summer. Something we can haul are bikes in the back and camp out in.

I appreciate the help. Where is the engine data plate going to be located so I can get the numbers next time I go to my shop. I will also check what the pump looks like next time I'm up there too.


B]Locate yer Engine Data Plate [/B]




 

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Discussion Starter #10
Hell yeah, you guys are badass. I've been swamped lately with work and school but I am for sure going to get up to my shop tomorrow and get something rolling.

After researching and reading your replies this looks like my plan so far:
1. Govenor spring mod and remove throttle stop if any
2. Get more fuel by playing with the injection pump
3. Install a pyrometer before playing around too much
4. ???

Let me know where I am wrong if at all. Also, what do you guys think about waste vegetable oil. From what I have heard if you get it filtered really well and still have a tank of regular diesel to run the engine at start and before turning it off, it looks like it is a feasible idea. No?

I appreciate the help again :beer:
 

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get a pyro before any pump mods. $150 now or thousands later.

WVO- it is quite possible in these engines, if done correctly. there is a lot more to it than you said, but do some more studying.....
 

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at least if you do WVO you should have enough room for some extra fuel :) You could drive thousand and never need to fill :grinpimp: Make sure you mouth them low though, haha.
 
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