I'm working on a t650 with a doosan engine that had weak injectors. Pulled injectors sent off to confirm, all four failed testing. Replaced all 4, fired engine which ran for 20 seconds and then died. Other than starting fluid it will not run. Rail pressure is exceeding 5k psi, filters are new, it appears the injectors simply aren't firing. I have no reason to think the ECU all of a sudden failed but I'm stumped at this point. Anyone encounter anything similar to this. Thanks I'm advance.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
Help Support SkidSteer Forum:
I guess the first thing just to rule it out is to do a compression test, starting fluid will light off at a lower compression where diesel will not. might want to find out what the suggested injector pressure is and confirm with a gauge , I know the newer direct injection diesels run at a higher pressure and I have no idea how much of a pressure difference window there between good and no run.
Compression is fine, pulled injectors hooked them up to lines outside of head and cranked the engine over to confirm the were functioning. They were not….sent them back to have tested and the passed all testing. Hooked a volt meter to injector harness and it shows it's receiving 2v. Is that low? I know on the larger Cat injectors their solenoids require upwards of a 100v to open. Don't know why this would be a issue all of a sudden being it did run on the old injectors but were just weak. Dealer suggested to swap $10k worth of parts which is just absolutely comical and a shame this is where this industry is at now.I guess the first thing just to rule it out is to do a compression test, starting fluid will light off at a lower compression where diesel will not. might want to find out what the suggested injector pressure is and confirm with a gauge , I know the newer direct injection diesels run at a higher pressure and I have no idea how much of a pressure difference window there between good and no run.
How did you go with this? Got one doing the exact same thing. Have other cats but don't want to swap out parts and have two out of service. Also suspect ecu. Put a new pump on snd cleaned out everything after the pump. Same.Compression is fine, pulled injectors hooked them up to lines outside of head and cranked the engine over to confirm the were functioning. They were not….sent them back to have tested and the passed all testing. Hooked a volt meter to injector harness and it shows it's receiving 2v. Is that low? I know on the larger Cat injectors their solenoids require upwards of a 100v to open. Don't know why this would be a issue all of a sudden being it did run on the old injectors but were just weak. Dealer suggested to swap $10k worth of parts which is just absolutely comical and a shame this is where this industry is at now.
On the Bobcats with Doosan engines, we have seen two that would not start, or could barely be coaxed into running, due to excessive hydraulic loading. Simply removing the drive belt let them start and run. The culprit was the Bobtach valve, on the one we could actually start it by opening the Bobtach while cranking. Seems the Doosan is sensitive to cranking speed, both of these would seem to "try" to start, even outrunning the starter, but would not actually take hold and go. Let us know what yours ends up needing.
salcidoariel81
New member
- Joined
- Dec 3, 2022
- Messages
- 4
Does this really fix itOn the Bobcats with Doosan engines, we have seen two that would not start, or could barely be coaxed into running, due to excessive hydraulic loading. Simply removing the drive belt let them start and run. The culprit was the Bobtach valve, on the one we could actually start it by opening the Bobtach while cranking. Seems the Doosan is sensitive to cranking speed, both of these would seem to "try" to start, even outrunning the starter, but would not actually take hold and go. Let us know what yours ends up needing.
Compression is fine, pulled injectors hooked them up to lines outside of head and cranked the engine over to confirm the were functioning. They were not….sent them back to have tested and the passed all testing. Hooked a volt meter to injector harness and it shows it's receiving 2v. Is that low? I know on the larger Cat injectors their solenoids require upwards of a 100v to open. Don't know why this would be a issue all of a sudden being it did run on the old injectors but were just weak. Dealer suggested to swap $10k worth of parts which is just absolutely comical and a shame this is where this industry is at now.
Compression is fine, pulled injectors hooked them up to lines outside of head and cranked the engine over to confirm the were functioning. They were not….sent them back to have tested and the passed all testing. Hooked a volt meter to injector harness and it shows it's receiving 2v. Is that low? I know on the larger Cat injectors their solenoids require upwards of a 100v to open. Don't know why this would be a issue all of a sudden being it did run on the old injectors but were just weak. Dealer suggested to swap $10k worth of parts which is just absolutely comical and a shame this is where this industry is at now.
What ended up fixing the problem, ECU? Having same exact issue.Compression is fine, pulled injectors hooked them up to lines outside of head and cranked the engine over to confirm the were functioning. They were not….sent them back to have tested and the passed all testing. Hooked a volt meter to injector harness and it shows it's receiving 2v. Is that low? I know on the larger Cat injectors their solenoids require upwards of a 100v to open. Don't know why this would be a issue all of a sudden being it did run on the old injectors but were just weak. Dealer suggested to swap $10k worth of parts which is just absolutely comical and a shame this is where this industry is at now.
