690 ELC throtle actuator bypass with a manual throtle cable

[skidad54]

The throtle actuator on my excavator quit working. The James River machanic told me to bypass it with a simple throtle cable. This would bypass all exectronics. Make my excavaor throtle all manual.
This excavator has a mechanical fuel pump. Does anyone know if the electronic throtle actuator causes a softer hydruliclic stroke.? Does the Hydraulic pump or the main valve know the difference from the command signal coming from the electronic throtle actuator or the manual throtle cable? Does the electronic throtle actuator instruct the hydraulic pump to make a softer hydraulic stroke?

does the hydraulic pump make a harder hydraulic stroke when it recieves the signal from the manual throtle cable maybe causing premature damage to the hydraulic pump?

 

[mg2361]

Welcome to HEF skidad54!

If my memory serves me correctly, the speed sensor combined with the switch panel throttle setting, not the physical throttle, determines what the pump may or may not do. The only thing that may affect the performance of the pump is the lights that you see when you choose an engine speed. "I" would stroke the pump differently than "L", which would be different than "E", etc.

So, I would think, with a mechanical cable and the engine at fast idle, set the throttle on the switch panel to "P", you should be fine, provided the electronic system is working as it should.

Regardless, engine speed adjustments (idle/full throttle) are critical. They must be within specifications.

Hopefully, someone with more knowledge on these will chime in.

 

[Diesel Dave]

@mg2361 nailed it all.
After installing the manual throttle cable , adjust the engine idle speed to 900 rpm, high idle speed 2150 rpm.

 

[thepumpguysc]

I have no experience doing this, but I have an idea..
If the inj pump is mechanical, it’ll have a throttle lever..
IF YES, u can achieve an answer to most of your questions by operating the engine BY HAND.. it’ll just simulate what u would do with a cable..
U hold/move the throttle and have someone else operate the controls..
I hope this gives u some ideas..
Good luck.