5145 inaccurate RPM after warm up

redobbin · Jul 15, 2022

As I understand it, the 5145 has a four cylinder engine, it should be as smooth as butter. If it is rough from contaminants in the fuel that is one thing, but otherwise, I would see this as an issue for warranty.

DaBear3428 · Jul 26, 2022

redobbin said:
As I understand it, the 5145 has a four cylinder engine, it should be as smooth as butter. If it is rough from contaminants in the fuel that is one thing, but otherwise, I would see this as an issue for warranty.

correct smooth as butter as i recall, just gets louder as the rpms go up, i will check mine tonight to see if i can detect anything at that rpm.
on a side note, in the older equipment the tach was run off of a signal from the alternator to sense alternator rpms and deducing engine rpms from that, the 5145 uses a common rail injection system which involves a crank sensor and computer to calculate fueling and therefore "knows" the rpms. The rpm signal is transmitted via digital signal from the computer to the cluster. The bottom line is that cleaning the analog wiring from the alt will not affect this rpm gage.

the 5145 has an ODBII connector under the seat BTW, mine has a cover that was lose when i recieved it, it is best to put the cover back on to keep water and stuff out of it.

redobbin · Aug 1, 2022

DaBear3428 said:
correct smooth as butter as i recall, just gets louder as the rpms go up, i will check mine tonight to see if i can detect anything at that rpm.
on a side note, in the older equipment the tach was run off of a signal from the alternator to sense alternator rpms and deducing engine rpms from that, the 5145 uses a common rail injection system which involves a crank sensor and computer to calculate fueling and therefore "knows" the rpms. The rpm signal is transmitted via digital signal from the computer to the cluster. The bottom line is that cleaning the analog wiring from the alt will not affect this rpm gage.

the 5145 has an ODBII connector under the seat BTW, mine has a cover that was lose when i recieved it, it is best to put the cover back on to keep water and stuff out of it.

Thanks for noting the differences in the way the tach is driven in the 5145 as compared to my older 4035.