763 C to F engine swap - boss - electronics?

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carl johansson

Active member
Joined
Nov 5, 2007
Messages
43
So far the engine swap has went well. With the FSM the process of removing the engine is quite simple, the manual has great pictures and easy to follow instructions. now I am ready to put the engine into a C model, and i have a question. The c model that will be complete does not have the BOSS setup, while the F Model does have the BOSS. can I just bolt the boss box to the c model - and plug in stuff and it will work - if I can should I? is the BOSS a good thing - or is the BOSS a POSS (the extra S stands for stinky!) Or should i swap over the C models wire harness onto the engine before I put it back into the unit? Thanks for the help, carl Johansson Auberry california
 

TriHonu

Well-known member
Joined
Apr 15, 2007
Messages
486
The BOSS system requires a different set of wiring harnesses, the BOSS controller, additional sensors and one additional relay.
The GOOD: The BOSS system is basically a controller that receives signals from temperature and pressure sensors in the engine, hydraulic and hydrostatic systems. The controller compares the input values to a range of acceptable levels. If any input signals are outside the acceptable range, the controller switches the fuel solenoid solenoid to a 30 second timer. This allows the engine be be started and run for only 30 seconds at a time so you can move or load the machine. This provides additional protection beyond the basic instruments. (By the way, you turn the fuel solenoid open by hand and put a wedge behind the lever and the engine will continue to run until you remove the wedge.
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)
The BAD: The controller and display are quite expensive if they break. The early BOSS systems 1993 and earlier were not the best that Bobcat could muster. They upgraded the system and it has evolved to system that is now in all Bobcats.
I have BOSS on my 763 with 2100 hrs and have not had any problems with it. I had a couple of people warn me about buying a machine with BOSS. I asked the dealer about removing it and they told me about having to buy all new wiring harnesses (read not cheap
emotion-9.gif
).
BOSS was designed to help prevent problems from getting really expensive by forcing you to deal with them before serious damage occurs. You will have to balance that benefit with the potential costs of maintaining the system. I like the idea of the controller keeping a closer eye on the systems to keep me from accidently destroying the expensive stuff. But have also decided that if the controller or display goes out, I'll probably end up removing the BOSS since it will be less expensive than replacing them.
Depending upon the condition of the loader and number of hours I don't think I would take the time to change out the all the wiring in the C series to install the BOSS system. There are alot of people who believe BOSS is a bad thing and may decrease the value of the loader in their eyes.
You will have to decide if the time and effort is worth it to you.
 

skidsteer.ca

Well-known member
Joined
Jan 20, 2006
Messages
3,853
The BOSS system requires a different set of wiring harnesses, the BOSS controller, additional sensors and one additional relay.
The GOOD: The BOSS system is basically a controller that receives signals from temperature and pressure sensors in the engine, hydraulic and hydrostatic systems. The controller compares the input values to a range of acceptable levels. If any input signals are outside the acceptable range, the controller switches the fuel solenoid solenoid to a 30 second timer. This allows the engine be be started and run for only 30 seconds at a time so you can move or load the machine. This provides additional protection beyond the basic instruments. (By the way, you turn the fuel solenoid open by hand and put a wedge behind the lever and the engine will continue to run until you remove the wedge. )
The BAD: The controller and display are quite expensive if they break. The early BOSS systems 1993 and earlier were not the best that Bobcat could muster. They upgraded the system and it has evolved to system that is now in all Bobcats.
I have BOSS on my 763 with 2100 hrs and have not had any problems with it. I had a couple of people warn me about buying a machine with BOSS. I asked the dealer about removing it and they told me about having to buy all new wiring harnesses (read not cheap ).
BOSS was designed to help prevent problems from getting really expensive by forcing you to deal with them before serious damage occurs. You will have to balance that benefit with the potential costs of maintaining the system. I like the idea of the controller keeping a closer eye on the systems to keep me from accidently destroying the expensive stuff. But have also decided that if the controller or display goes out, I'll probably end up removing the BOSS since it will be less expensive than replacing them.
Depending upon the condition of the loader and number of hours I don't think I would take the time to change out the all the wiring in the C series to install the BOSS system. There are alot of people who believe BOSS is a bad thing and may decrease the value of the loader in their eyes.
You will have to decide if the time and effort is worth it to you.
Imo the boss was somthing that should have been left in the idea phase. I had a 93 753 that needed a new boss computer and several sendors between 2000 and 3000 hours.
I have a 00 773 g thats on its second computer duo to a faulty hi water temp reading killing the engines fuel supply. We spent 2 summer seasons trouble shooting the intermittant hi temp reading, swapping out thermostats, sendors, guage panels and finally the computer itself.
If you want automatic engine and /or hydraulic protection visit www.fwmurphy.com and purchase some of their stuff. Their entire system will cost less then one boss computer and if it acts up you have a guage to verify the faulty ready as well as the horn or shutdown system. You elect how to club the operator over the head to wake him up. Also you will know how to trouble shoot it as its your design.
Both systems require good integrity in the wire harness, something not always easy to maintain on a offroad machine. Search 'boss" for previous post on this topic.
In all honesty there is no doubt in my mind what I would do. Bobcat should not be allowed to design any electronic component more complicated then a alternator diode.
Ken
 

Idoitall

Well-known member
Joined
Mar 17, 2007
Messages
126
Imo the boss was somthing that should have been left in the idea phase. I had a 93 753 that needed a new boss computer and several sendors between 2000 and 3000 hours.
I have a 00 773 g thats on its second computer duo to a faulty hi water temp reading killing the engines fuel supply. We spent 2 summer seasons trouble shooting the intermittant hi temp reading, swapping out thermostats, sendors, guage panels and finally the computer itself.
If you want automatic engine and /or hydraulic protection visit www.fwmurphy.com and purchase some of their stuff. Their entire system will cost less then one boss computer and if it acts up you have a guage to verify the faulty ready as well as the horn or shutdown system. You elect how to club the operator over the head to wake him up. Also you will know how to trouble shoot it as its your design.
Both systems require good integrity in the wire harness, something not always easy to maintain on a offroad machine. Search 'boss" for previous post on this topic.
In all honesty there is no doubt in my mind what I would do. Bobcat should not be allowed to design any electronic component more complicated then a alternator diode.
Ken
As I have already found, this forum contains a wealth of knowledge. So, I have a couple of questions about the BOSS system. First, is this the same as BICS that I have seen on machines?

In my search for a machine I'm going to look at a '96 753 a second time. It's been refurb'd and looks and runs very good with 1600 hours showing (??). Does this machine have the BOSS system? And how do you recognize this? If I recall, there were 2-3 analog gauges and the key in the upper right & maybe the hour meter. On the left was a few lights and a button for "traction control (??)" I think.

I would prefer a simple machine w/o either of these systems, so is there a specific model or year to look for?

Thanks in advance for the great information and the know how.
 

skidsteer.ca

Well-known member
Joined
Jan 20, 2006
Messages
3,853
As I have already found, this forum contains a wealth of knowledge. So, I have a couple of questions about the BOSS system. First, is this the same as BICS that I have seen on machines?

In my search for a machine I'm going to look at a '96 753 a second time. It's been refurb'd and looks and runs very good with 1600 hours showing (??). Does this machine have the BOSS system? And how do you recognize this? If I recall, there were 2-3 analog gauges and the key in the upper right & maybe the hour meter. On the left was a few lights and a button for "traction control (??)" I think.

I would prefer a simple machine w/o either of these systems, so is there a specific model or year to look for?

Thanks in advance for the great information and the know how.
Bics is Bobcat Interlock Control Sytem. It is a operator protection system that is present from all models 1994 up the the start of the G series. It is a aluminum box inside the operator compartment on the RH side of the seat with 5 green lights on it. It hydraulically locks the foot pedals functions and prevents the park brake from releasing. Also it is standard equipment
Boss on the other had is a optional engine protection system that was used up until the G series. The G's have all the boss features but it became standard equipment on the G's and they dropped the "boss" name.
Boss equipped machines do not have anolog guages, the have a special guage display with bar graph guages and a series of warning lights. All this beeps at the operator and/or will shut down the machine if coolant is low or to hot, engine overspeeds, oil pressure is lost, hyd charge pressure is lost, fuel is low, air filter is plugged, they automatically time the glow plugs.. when the function correctly. When they screw up they can shut you off for any of these reasons too.
It seems like a good idea but plan on you maintenace cost rising to keep it functioning.
Ken
 

skidsteer.ca

Well-known member
Joined
Jan 20, 2006
Messages
3,853
Bics is Bobcat Interlock Control Sytem. It is a operator protection system that is present from all models 1994 up the the start of the G series. It is a aluminum box inside the operator compartment on the RH side of the seat with 5 green lights on it. It hydraulically locks the foot pedals functions and prevents the park brake from releasing. Also it is standard equipment
Boss on the other had is a optional engine protection system that was used up until the G series. The G's have all the boss features but it became standard equipment on the G's and they dropped the "boss" name.
Boss equipped machines do not have anolog guages, the have a special guage display with bar graph guages and a series of warning lights. All this beeps at the operator and/or will shut down the machine if coolant is low or to hot, engine overspeeds, oil pressure is lost, hyd charge pressure is lost, fuel is low, air filter is plugged, they automatically time the glow plugs.. when the function correctly. When they screw up they can shut you off for any of these reasons too.
It seems like a good idea but plan on you maintenace cost rising to keep it functioning.
Ken
Idoitall
The machine you mention does not appear to be a boss unless its be converted back. Imo it worth more then the one with the option not to have the problems.
The downside is the hobbs hour meter in the std model can be replaced for $30 to roll back the hours. Where on the boss machine you have to buy a $600 tin box and have a dealer program it.
Ken
 

Tazza

Moderator
Staff member
Joined
Dec 7, 2004
Messages
16,844
Bics is Bobcat Interlock Control Sytem. It is a operator protection system that is present from all models 1994 up the the start of the G series. It is a aluminum box inside the operator compartment on the RH side of the seat with 5 green lights on it. It hydraulically locks the foot pedals functions and prevents the park brake from releasing. Also it is standard equipment
Boss on the other had is a optional engine protection system that was used up until the G series. The G's have all the boss features but it became standard equipment on the G's and they dropped the "boss" name.
Boss equipped machines do not have anolog guages, the have a special guage display with bar graph guages and a series of warning lights. All this beeps at the operator and/or will shut down the machine if coolant is low or to hot, engine overspeeds, oil pressure is lost, hyd charge pressure is lost, fuel is low, air filter is plugged, they automatically time the glow plugs.. when the function correctly. When they screw up they can shut you off for any of these reasons too.
It seems like a good idea but plan on you maintenace cost rising to keep it functioning.
Ken
In theory the BOSS system is great, it looks after your engine and in the case of a fault it will do its best to save the engine from damage. I remember Your story Ken, all the nightmares with finding the problem caused by a bad sender. When they work it is an asset but when its not working......
If you want a machine thats easy to maintain you can't go past a 743/743B very simple to keep running but doesn't have all the fancy controls like push button aux hydraulics.
I do like the idea of the BICS system especially for running a hoe attachment but simply kicking the park brake on works equally well!.
 
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