742B Fuel Shutoff Solenoid?

[Tango-Charlie]

I'm a new Bobcat 742B owner and new to this forum. The engine is the Mitsubishi gas. When I was cleaning it I could smell an order of gas but never found any leak after checking the fuel lines, fuel filter, and fuel shutoff valve next to the fuel tank. After spending several hours cleaning the machine and replacing the governor and alternator belts and the fuel filter everything was working and engine starting and running fine.
I ran the 742B again and pulled it into the garage and again could smell gas but did not find any leak or drip. After running it again I parked it in the barn and turned off the manual fuel shutoff valve next to the gas tank because of the order of gas.
A couple days later I went out and turned on the gas shutoff valve and cranked, cranked and cranked and it finally started on full choke. I would also note that the outside temperature was about 20 degrees but had the block heater plugged in for about an hour to heat the block up. It died after about a minute or two and had to restart it about 6 times.
The last time it stayed running for about 4 minutes and then died out sounding like fuel starvation. After letting it sit for a couple minutes it started again and I let it warm up. It ran fine and I pulled it into the heated garage again and shut it off and could again smell the heavy odor of gas but couldn't find any leak.
I have the service and parts manuals and thinking the fuel solenoid is sticking open when shutoff I have a couple of questions as the manuals does not discuss it. The fuel shutoff solenoid in the parts and maintenance manual only shows 1 wire so it must ground itself.
Questions:
1. If the fuel shutoff solenoid is bad and will not close when the ignition key is turned off will the carburetor dump fuel overboard creating the heavy gas smell.
2. After turning off the fuel valve next to the gas tank and letting the machine sit for a couple of days and if the fuel shut off solenoid is bad will this dump the remaining fuel in the fuel line between the carburetor and the tank shut off valve making it hard to start and die out until it draws enough fuel from the tank?
3. The hard start problem only occurred after I turned off the fuel shutoff valve next to the gas tank and let it sit for a couple days. All other times when not shutting off the manual fuel shutoff valve it always started up right away. Would this contribute to possibly a bad fuel solenoid?
Any other suggestions or help would be appreciated to try and figure out where the heavy odor of gas is coming from and the starting problem after turning off the manual fuel shutoff valve next to the gas tank.

 

[jerry]

On your machine is there a solenoid on the gas line and also on the carb bowl? I would suspect the bowl needle valve not holding and leaking down even with just the light pressure of the fuel in the line after you turn the manual valve off. Check the motor oll also for the smell of gas.

 

[Tango-Charlie]

On your machine is there a solenoid on the gas line and also on the carb bowl? I would suspect the bowl needle valve not holding and leaking down even with just the light pressure of the fuel in the line after you turn the manual valve off. Check the motor oll also for the smell of gas.

On my 742B Mitsubishi the only fuel shut off solenoid is on the carburetor. I'll check the oil and see if I have any gas smell and let you know what I find.

 

[Tango-Charlie]

On your machine is there a solenoid on the gas line and also on the carb bowl? I would suspect the bowl needle valve not holding and leaking down even with just the light pressure of the fuel in the line after you turn the manual valve off. Check the motor oll also for the smell of gas.

I just ran out and pulled the dip stick and ran my finger and thumb together on the dip stick. The oil feels correct and I didn't smell any hint of gas. Thanks

 

[jerry]

I just ran out and pulled the dip stick and ran my finger and thumb together on the dip stick. The oil feels correct and I didn't smell any hint of gas. Thanks

The 632 had a 12v fuel shutoff solenoid on the firewall fuel line and the carb one. The one in the carb is to prevent dieseling or runon of the engine when it is shut down hot. If there are no leaks I would guess the float needle valve needs r and r. Check your choke linkage visually In the carb to be sure it is closing completely also, that may be the hard starting cause.

 

[Tango-Charlie]

The 632 had a 12v fuel shutoff solenoid on the firewall fuel line and the carb one. The one in the carb is to prevent dieseling or runon of the engine when it is shut down hot. If there are no leaks I would guess the float needle valve needs r and r. Check your choke linkage visually In the carb to be sure it is closing completely also, that may be the hard starting cause.

I think by everyone's help and checking the engine compartment I've figured out the problem. It appears that the previous owner took out the firewall fuel shutoff solenoid as there is a ground wire dangling and another connector with nothing plugged into it. This is probably where the fuel shutoff solenoid would have been. QUESTION: If the fuel shutoff solenoid was removed, in other words the fuel is not shut off, is this possibly why I'm getting a gasoline smell unless turning off the manual fuel shutoff valve? The electronic fuel shutoff valve must have been in there for a reason. I haven't checked but are there any good sources to find the electronic fuel shutoff solenoid if this is my problem? Thanks

 

[Tango-Charlie]

I think by everyone's help and checking the engine compartment I've figured out the problem. It appears that the previous owner took out the firewall fuel shutoff solenoid as there is a ground wire dangling and another connector with nothing plugged into it. This is probably where the fuel shutoff solenoid would have been. QUESTION: If the fuel shutoff solenoid was removed, in other words the fuel is not shut off, is this possibly why I'm getting a gasoline smell unless turning off the manual fuel shutoff valve? The electronic fuel shutoff valve must have been in there for a reason. I haven't checked but are there any good sources to find the electronic fuel shutoff solenoid if this is my problem? Thanks

QUESTION: If the fuel (gas) shutoff solenoid was removed, in other words the fuel is not shut off, is this possibly why I'm getting a gasoline smell unless turning off the manual fuel shutoff valve? The electronic fuel shutoff valve must have been in there for a reason. Any answers would be helpful. Thanks

 

[Tazza]

QUESTION: If the fuel (gas) shutoff solenoid was removed, in other words the fuel is not shut off, is this possibly why I'm getting a gasoline smell unless turning off the manual fuel shutoff valve? The electronic fuel shutoff valve must have been in there for a reason. Any answers would be helpful. Thanks

If the solenoid was removed, it is possible that the smell is because of that.

 

[Tango-Charlie]

If the solenoid was removed, it is possible that the smell is because of that.

When the new fuel shutoff solenoid comes in and I get it installed I post the results. Thanks

 

[wings5j]

When the new fuel shutoff solenoid comes in and I get it installed I post the results. Thanks

Hi, I also have a 742B. When I first got it, anytime I parked it in the shop, it would make a bad gas smell. One day I did a tune up and decided to clean the carburetor as well. Jerry's comment about the needle valve might be something to think about. At any rate, my gas smell went away. Starting can be an issue but seems to be related to technique as much as anything. The right number of throttle movements, right amount of choke and then you hold your tongue just the right way ;-) It seems to need a new set of points about every 150 hours or so. Hope that helps, John

 

[Tango-Charlie]

Hi, I also have a 742B. When I first got it, anytime I parked it in the shop, it would make a bad gas smell. One day I did a tune up and decided to clean the carburetor as well. Jerry's comment about the needle valve might be something to think about. At any rate, my gas smell went away. Starting can be an issue but seems to be related to technique as much as anything. The right number of throttle movements, right amount of choke and then you hold your tongue just the right way ;-) It seems to need a new set of points about every 150 hours or so. Hope that helps, John

Hey John, Thanks for the reply. Does your 742B have the Mitsubishi engine with the fuel shutoff solenoid? If it does and it's in the fuel line between the fuel pump and fuel filter I have another question. The original fuel shutoff solenoid part number 6559117 has been replaced with new number 7024822 which I have ordered. It appears the new fuel shutoff solenoid may be larger. My question is, being my fuel shutoff solenoid had been totally removed from my 742B, is there any type of bracket that attaches to it or is it just hanging in the fuel line? Also, do you shut off the manual fuel shutoff valve below the tank when you don't use it? Another question. You said you did a full tune up which I'm also going to be doing and have ordered the parts. I'm also going to convert to electronic ignition being they make a conversion kit to eliminate the need to be replacing points all the time. That too is on order and hopefully will be receiving in the next couple of weeks. But you said "cleaned carburetor". Did you do an entire carburetor rebuild by removing it from the engine/stripping everything and purchase a rebuilt kit with all new needles/gaskets along with boiling it out? Or did you clean it by some other fashion? I did order the carburetor rebuild gaskets and needle kit incase I have to go the entire rebuild route. I know in the old days when working on cars some tried removing certain needle valves and using spray carburetor cleaner and clean the port/needle and then reinsert. The key to this was to ensure to remember the number of turns when removing the needle valve. Just curious if this may have been what you did. Also, I read in another post that the 742B Mitsubishi can be temperamental in cold weather but tried what another post said and it was a lot easier in extreme cold weather starting. 1. Block heater turned on 4 hours prior to starting. 2. Start on full choke at about 1/3 throttle and let run for about 3-4 minutes on full choke. 3. After 4-5 minutes ran on 1/2 choke for another 5-10 minutes while hydraulic fluid was warming. Seemed to work for me the last time I did a cold weather start at about 10 degrees. Thanks for the help and will be waiting for your reply on the carb stuff.

 

[mmsllc]

Hey John, Thanks for the reply. Does your 742B have the Mitsubishi engine with the fuel shutoff solenoid? If it does and it's in the fuel line between the fuel pump and fuel filter I have another question. The original fuel shutoff solenoid part number 6559117 has been replaced with new number 7024822 which I have ordered. It appears the new fuel shutoff solenoid may be larger. My question is, being my fuel shutoff solenoid had been totally removed from my 742B, is there any type of bracket that attaches to it or is it just hanging in the fuel line? Also, do you shut off the manual fuel shutoff valve below the tank when you don't use it? Another question. You said you did a full tune up which I'm also going to be doing and have ordered the parts. I'm also going to convert to electronic ignition being they make a conversion kit to eliminate the need to be replacing points all the time. That too is on order and hopefully will be receiving in the next couple of weeks. But you said "cleaned carburetor". Did you do an entire carburetor rebuild by removing it from the engine/stripping everything and purchase a rebuilt kit with all new needles/gaskets along with boiling it out? Or did you clean it by some other fashion? I did order the carburetor rebuild gaskets and needle kit incase I have to go the entire rebuild route. I know in the old days when working on cars some tried removing certain needle valves and using spray carburetor cleaner and clean the port/needle and then reinsert. The key to this was to ensure to remember the number of turns when removing the needle valve. Just curious if this may have been what you did. Also, I read in another post that the 742B Mitsubishi can be temperamental in cold weather but tried what another post said and it was a lot easier in extreme cold weather starting. 1. Block heater turned on 4 hours prior to starting. 2. Start on full choke at about 1/3 throttle and let run for about 3-4 minutes on full choke. 3. After 4-5 minutes ran on 1/2 choke for another 5-10 minutes while hydraulic fluid was warming. Seemed to work for me the last time I did a cold weather start at about 10 degrees. Thanks for the help and will be waiting for your reply on the carb stuff.

The fuel shutdown solenoid is actually there to reduce the amount of fuel pressure that would otherwise be put on the small needle valve inside of the carburetor. By it not being there, it fuel can force its way into the cylinder. That is the main idea as to what it is designed to do. That should also help reduce the possibility of have the engine flooding out when the key is off. This issue is even worse if the fuel tank mounts above the carburetor because of increased gravity. To answer your question, it was most likely removed as it (most likely) went bad & was not available to be replaced. After it ran good, it was very easy to forget.

 

[Tango-Charlie]

The fuel shutdown solenoid is actually there to reduce the amount of fuel pressure that would otherwise be put on the small needle valve inside of the carburetor. By it not being there, it fuel can force its way into the cylinder. That is the main idea as to what it is designed to do. That should also help reduce the possibility of have the engine flooding out when the key is off. This issue is even worse if the fuel tank mounts above the carburetor because of increased gravity. To answer your question, it was most likely removed as it (most likely) went bad & was not available to be replaced. After it ran good, it was very easy to forget.

I know that it's been a while since I replied but have since found the time to purchase and reinstall a new Bobcat gasoline fuel solenoid in my Mitsubishi 4G32 742B Bobcat. Bobcat has a replacement solenoid part number 7024822 which costs around $200.00. I purchased and installed the new fuel solenoid after making a bracket to hold it from an ignition coil bracket. I just had to put the coil bracket into the vise and do some new bends and it worked great. I mounted the fuel solenoid on the right side below the radiator overflow tank and behind the ignition coil. At the same time I replaced the old fuel hoses and fuel filter to the shutoff valve. I then ran the ground wire to the pigtail where the original had been removed from. I found the connector for the hot lead pigtail that was a short connector off the hot ignition lead that went to the ignition side of the ceramic resistor. I checked the lead to insure it was hot when the ignition switch was turned on and then cold when turned off. Needless to say after everything was connected and I turned on the fuel shutoff valve (and left it on) the solenoid did it's job. No more gasoline smell after shutting off the engine which closed the fuel solenoid. So in essence my problem must have been gas continuing to run into the turned off engine thus creating the gasoline smell probably from gravity being the tank is higher than the carb. Thanks for all the opinions and help and hopefully this helps someone in the future.

 

[wings5j]

I know that it's been a while since I replied but have since found the time to purchase and reinstall a new Bobcat gasoline fuel solenoid in my Mitsubishi 4G32 742B Bobcat. Bobcat has a replacement solenoid part number 7024822 which costs around $200.00. I purchased and installed the new fuel solenoid after making a bracket to hold it from an ignition coil bracket. I just had to put the coil bracket into the vise and do some new bends and it worked great. I mounted the fuel solenoid on the right side below the radiator overflow tank and behind the ignition coil. At the same time I replaced the old fuel hoses and fuel filter to the shutoff valve. I then ran the ground wire to the pigtail where the original had been removed from. I found the connector for the hot lead pigtail that was a short connector off the hot ignition lead that went to the ignition side of the ceramic resistor. I checked the lead to insure it was hot when the ignition switch was turned on and then cold when turned off. Needless to say after everything was connected and I turned on the fuel shutoff valve (and left it on) the solenoid did it's job. No more gasoline smell after shutting off the engine which closed the fuel solenoid. So in essence my problem must have been gas continuing to run into the turned off engine thus creating the gasoline smell probably from gravity being the tank is higher than the carb. Thanks for all the opinions and help and hopefully this helps someone in the future.

Hi, sorry it took so long to reply. My full time job often gets in the way of any Bobcat time. Currently I am out of town at work and so I will have to check on some of this when I get home. I will quote your post and try to fill in some of the blanks: "Hey John, Thanks for the reply. Does your 742B have the Mitsubishi engine with the fuel shutoff solenoid? [Mine has the manual shutoff below the tank and a solenoid at the carburetor] If it does and it's in the fuel line between the fuel pump and fuel filter I have another question. The original fuel shutoff solenoid part number 6559117 has been replaced with new number 7024822 which I have ordered. It appears the new fuel shutoff solenoid may be larger. My question is, being my fuel shutoff solenoid had been totally removed from my 742B, is there any type of bracket that attaches to it or is it just hanging in the fuel line? [Not sure on that] Also, do you shut off the manual fuel shutoff valve below the tank when you don't use it? [I only use the manual shutoff when changing the filter.] Another question. You said you did a full tune up which I'm also going to be doing and have ordered the parts. I'm also going to convert to electronic ignition being they make a conversion kit to eliminate the need to be replacing points all the time. That too is on order and hopefully will be receiving in the next couple of weeks. [I have been planning to convert to electronic ignition for a long time. If you could send me the details on what you ordered, that would be great.] But you said "cleaned carburetor". Did you do an entire carburetor rebuild by removing it from the engine/stripping everything and purchase a rebuilt kit with all new needles/gaskets along with boiling it out? Or did you clean it by some other fashion? I did order the carburetor rebuild gaskets and needle kit incase I have to go the entire rebuild route.[I believe I put in a new needle and seat but don't recall any other parts. I wrote down all the jet settings, etc., took it all apart and cleaned it in carb cleaner and put it back together. There is a ball in one of the cavities that you have to watch out for or it falls out when you aren't looking and it is not easy to figure out where it goes ] I know in the old days when working on cars some tried removing certain needle valves and using spray carburetor cleaner and clean the port/needle and then reinsert. The key to this was to ensure to remember the number of turns when removing the needle valve. Just curious if this may have been what you did. Also, I read in another post that the 742B Mitsubishi can be temperamental in cold weather but tried what another post said and it was a lot easier in extreme cold weather starting. 1. Block heater turned on 4 hours prior to starting. 2. Start on full choke at about 1/3 throttle and let run for about 3-4 minutes on full choke. 3. After 4-5 minutes ran on 1/2 choke for another 5-10 minutes while hydraulic fluid was warming. Seemed to work for me the last time I did a cold weather start at about 10 degrees. Thanks for the helpSmileyand will be waiting for your reply on the carb stuff. I do pretty good at keeping up with email so here is my address Hope to hear from you regarding the electronic ignition kit. John

 

[wings5j]

Hi, sorry it took so long to reply. My full time job often gets in the way of any Bobcat time. Currently I am out of town at work and so I will have to check on some of this when I get home. I will quote your post and try to fill in some of the blanks: "Hey John, Thanks for the reply. Does your 742B have the Mitsubishi engine with the fuel shutoff solenoid? [Mine has the manual shutoff below the tank and a solenoid at the carburetor] If it does and it's in the fuel line between the fuel pump and fuel filter I have another question. The original fuel shutoff solenoid part number 6559117 has been replaced with new number 7024822 which I have ordered. It appears the new fuel shutoff solenoid may be larger. My question is, being my fuel shutoff solenoid had been totally removed from my 742B, is there any type of bracket that attaches to it or is it just hanging in the fuel line? [Not sure on that] Also, do you shut off the manual fuel shutoff valve below the tank when you don't use it? [I only use the manual shutoff when changing the filter.] Another question. You said you did a full tune up which I'm also going to be doing and have ordered the parts. I'm also going to convert to electronic ignition being they make a conversion kit to eliminate the need to be replacing points all the time. That too is on order and hopefully will be receiving in the next couple of weeks. [I have been planning to convert to electronic ignition for a long time. If you could send me the details on what you ordered, that would be great.] But you said "cleaned carburetor". Did you do an entire carburetor rebuild by removing it from the engine/stripping everything and purchase a rebuilt kit with all new needles/gaskets along with boiling it out? Or did you clean it by some other fashion? I did order the carburetor rebuild gaskets and needle kit incase I have to go the entire rebuild route.[I believe I put in a new needle and seat but don't recall any other parts. I wrote down all the jet settings, etc., took it all apart and cleaned it in carb cleaner and put it back together. There is a ball in one of the cavities that you have to watch out for or it falls out when you aren't looking and it is not easy to figure out where it goes ] I know in the old days when working on cars some tried removing certain needle valves and using spray carburetor cleaner and clean the port/needle and then reinsert. The key to this was to ensure to remember the number of turns when removing the needle valve. Just curious if this may have been what you did. Also, I read in another post that the 742B Mitsubishi can be temperamental in cold weather but tried what another post said and it was a lot easier in extreme cold weather starting. 1. Block heater turned on 4 hours prior to starting. 2. Start on full choke at about 1/3 throttle and let run for about 3-4 minutes on full choke. 3. After 4-5 minutes ran on 1/2 choke for another 5-10 minutes while hydraulic fluid was warming. Seemed to work for me the last time I did a cold weather start at about 10 degrees. Thanks for the helpSmileyand will be waiting for your reply on the carb stuff. I do pretty good at keeping up with email so here is my address Hope to hear from you regarding the electronic ignition kit. John

Last post must not have liked the format for my email address. I will try again but if it does not show up here, I believe you can find it in my profile. Guess I had better check and see if it needs updating. [email protected]

 

[Tango-Charlie]

Hi, sorry it took so long to reply. My full time job often gets in the way of any Bobcat time. Currently I am out of town at work and so I will have to check on some of this when I get home. I will quote your post and try to fill in some of the blanks: "Hey John, Thanks for the reply. Does your 742B have the Mitsubishi engine with the fuel shutoff solenoid? [Mine has the manual shutoff below the tank and a solenoid at the carburetor] If it does and it's in the fuel line between the fuel pump and fuel filter I have another question. The original fuel shutoff solenoid part number 6559117 has been replaced with new number 7024822 which I have ordered. It appears the new fuel shutoff solenoid may be larger. My question is, being my fuel shutoff solenoid had been totally removed from my 742B, is there any type of bracket that attaches to it or is it just hanging in the fuel line? [Not sure on that] Also, do you shut off the manual fuel shutoff valve below the tank when you don't use it? [I only use the manual shutoff when changing the filter.] Another question. You said you did a full tune up which I'm also going to be doing and have ordered the parts. I'm also going to convert to electronic ignition being they make a conversion kit to eliminate the need to be replacing points all the time. That too is on order and hopefully will be receiving in the next couple of weeks. [I have been planning to convert to electronic ignition for a long time. If you could send me the details on what you ordered, that would be great.] But you said "cleaned carburetor". Did you do an entire carburetor rebuild by removing it from the engine/stripping everything and purchase a rebuilt kit with all new needles/gaskets along with boiling it out? Or did you clean it by some other fashion? I did order the carburetor rebuild gaskets and needle kit incase I have to go the entire rebuild route.[I believe I put in a new needle and seat but don't recall any other parts. I wrote down all the jet settings, etc., took it all apart and cleaned it in carb cleaner and put it back together. There is a ball in one of the cavities that you have to watch out for or it falls out when you aren't looking and it is not easy to figure out where it goes ] I know in the old days when working on cars some tried removing certain needle valves and using spray carburetor cleaner and clean the port/needle and then reinsert. The key to this was to ensure to remember the number of turns when removing the needle valve. Just curious if this may have been what you did. Also, I read in another post that the 742B Mitsubishi can be temperamental in cold weather but tried what another post said and it was a lot easier in extreme cold weather starting. 1. Block heater turned on 4 hours prior to starting. 2. Start on full choke at about 1/3 throttle and let run for about 3-4 minutes on full choke. 3. After 4-5 minutes ran on 1/2 choke for another 5-10 minutes while hydraulic fluid was warming. Seemed to work for me the last time I did a cold weather start at about 10 degrees. Thanks for the helpSmileyand will be waiting for your reply on the carb stuff. I do pretty good at keeping up with email so here is my address Hope to hear from you regarding the electronic ignition kit. John

Sorry for the late reply to your questions. My 742B has the Mitsubishi 4G32 gas engine. I mounted my fuel shutoff vale on the sidewall in an old 12v coil bracket. With a couple easy mods its work out great. After installing the new electronic fuel shutoff valve I leave the manual gas line shut off always open. I haven't had any smell of gas and it works great. The only time I would use the manual valve would be for servicing anything on the fuel lines. Just a note of the electronic fuel shut off valve. When I go to start the machine I turn the key on for a couple seconds which opens the fuel valve and then full choke and it fires right up. I go to 1/2 choke for about 30 seconds and then choke off. It's never been easier to start. I converted to the Pertronix electronic ignition and it has never run better. As far a cold starts it seems the block heater turned on for about 4 hours before starting coupled with the electronic ignition has solved all my problems. Couldn't be happier with my workhorse.

 

[wings5j]

Sorry for the late reply to your questions. My 742B has the Mitsubishi 4G32 gas engine. I mounted my fuel shutoff vale on the sidewall in an old 12v coil bracket. With a couple easy mods its work out great. After installing the new electronic fuel shutoff valve I leave the manual gas line shut off always open. I haven't had any smell of gas and it works great. The only time I would use the manual valve would be for servicing anything on the fuel lines. Just a note of the electronic fuel shut off valve. When I go to start the machine I turn the key on for a couple seconds which opens the fuel valve and then full choke and it fires right up. I go to 1/2 choke for about 30 seconds and then choke off. It's never been easier to start. I converted to the Pertronix electronic ignition and it has never run better. As far a cold starts it seems the block heater turned on for about 4 hours before starting coupled with the electronic ignition has solved all my problems. Couldn't be happier with my workhorse.

Glad to hear it and thanks for the update.