1995 225 TXRU fuel system 76 degree motor

[bajakeith]

I have the yammy service manual for this motor, but it lacks good info about the fuel enrichment system and the electric fuel pump !! looking to understand what and when the enrichment should be working and how to test....This motor wins for having the most fuel lines of ANY motor I have ever seen..LOL !! Thanks in advance for any help.......K...

[rodbolt17]

the pump draws fuel from #6cyl carb bowl, lower stbd carb.
it sends this fuel to all 6 enrichment solenoids via a 6PSI regulator.
based on inputs from the temp sensor,knock sensor and TPS it can vary the A/F mixture about 20%.
pump runs anytime the key is on.
a stuck open T-stst on the stbd head can blow a piston due to the #6 fuel bowl cant stay full at high RPM's.

[bajakeith]

fuel enrichment testing

Thanks sir RODBOLT...I understand that...was looking for temp vs duty time and cycle...basic testing flow chart or anyway to check that the system is working right...and the pressure reg on this motor is not adjustable as the service manual shows it to be (sigh!) This motor has enough hoses to get in the record book...anyway ,,thinking a scratchy TPS may be the problem as the problem is variable as to when it runs poor..the owner states" has no pattern" and went tru carbs today and found all float levels LOW !!! also am going to use the magic sauce called deoxit on all connectors........This stuff works !! ...a must have next to my fluke !!.....Thanks for your reply...K

[rodbolt17]

there is no spec on enrichment duty cycle.
they are used for cold start enrichment,acceleration,deaccereation,and knock detect.
once warm and the throttle is set they are not used.

a loose knock sensor can drive you nuts.
remember this engine can only display a code when its active,it does not store codes.

[bajakeith]

Thanks RODBOLT 17

Went thru the carbs today and raised the float levels to spec (15.5) they were ALL low..custermer came back with a big grin!! running sweet now !! think the big E gas might have swelled the plastic button on the needle valve...or some yahoo went in and screwed with the floats !!! thanks for your time.................K