As the title suggests, I'm curious about the process of adjusting the injection pump timing on my b7100. I have the WSM, and it describes how to check said timing, only saying if it isn't correct, to adjust it. I can't find where it talks about doing that. Here's the reason I want to check it out;
When I start it cold, I get a lot of white "smoke" (smells like raw fuel). Glow plugs may be a tad weak, but they seem to work OK if let them run about 30 seconds. They're on the list of things to check this weekend for verification. After letting it warm up until the coolant temp it about 140-150F, I throttle up to move to where I'm working and the white smoke returns, but in random puffs and fairly faint. I engage the MMM, open the throttle up, and more random puffs of white smoke. After mowing for about 10 minutes, my coolant temp creeps up to about 225F. Radiator is clean inside and out, and the chaff screen is clear as well. I always blow everything out with an air compressor before, during and after mowing because of how sensitive this type of coolant system is to airflow. On top of this, when under a heavy load, I'll get the expected small amount of black smoke, but with additional puffs of white smoke.
It used to be, when mowing, my coolant temps would hang around 195-205F depending on engine load, but that average has been creeping up all season. In the spring, I installed new injectors (from Kubota) and bled the system, new air and fuel filters, flushed and filled the coolant system. I did new injectors so I'd have a spare set if needed. The old ones will get rebuilt and stored in a sealed container for use if needed later. I've read that improper injection pump timing can cause high engine temps and unburnt fuel issues.
Herein lies the question: Does injection pump timing migrate (either retard or advance) as the pump ages? If so, what's the procedure for adjusting?
EDIT: It's an old style B7100HST with ~3000 hours. No big modifications. Mechanical coolant temp gauge.
Thank you for any and all assistance with this.
When I start it cold, I get a lot of white "smoke" (smells like raw fuel). Glow plugs may be a tad weak, but they seem to work OK if let them run about 30 seconds. They're on the list of things to check this weekend for verification. After letting it warm up until the coolant temp it about 140-150F, I throttle up to move to where I'm working and the white smoke returns, but in random puffs and fairly faint. I engage the MMM, open the throttle up, and more random puffs of white smoke. After mowing for about 10 minutes, my coolant temp creeps up to about 225F. Radiator is clean inside and out, and the chaff screen is clear as well. I always blow everything out with an air compressor before, during and after mowing because of how sensitive this type of coolant system is to airflow. On top of this, when under a heavy load, I'll get the expected small amount of black smoke, but with additional puffs of white smoke.
It used to be, when mowing, my coolant temps would hang around 195-205F depending on engine load, but that average has been creeping up all season. In the spring, I installed new injectors (from Kubota) and bled the system, new air and fuel filters, flushed and filled the coolant system. I did new injectors so I'd have a spare set if needed. The old ones will get rebuilt and stored in a sealed container for use if needed later. I've read that improper injection pump timing can cause high engine temps and unburnt fuel issues.
Herein lies the question: Does injection pump timing migrate (either retard or advance) as the pump ages? If so, what's the procedure for adjusting?
EDIT: It's an old style B7100HST with ~3000 hours. No big modifications. Mechanical coolant temp gauge.
Thank you for any and all assistance with this.
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