Replace high-pressure fuel pump in VST and now fuel pouring out at the ….

[jkscarab]

Big thanks to Joe54 and EuroepanAM as my freaking VST needle shuts off perfectly!! I had to bend the brass tang more than 0.020” to about 0.030” to get needle to fully seat- just fyi to others watching this thread.

My next steps from previous comments

1. loosen the 2 plenum hex screws and tilt the motor fully upward to get any fuel to leak out of the plenum from flooding previously.
2. Removed bottom 2 spark plugs and spin the motor around manually (no spark)via wrench on top of motor.

>>>Anything else should do before turning the key?

thanks again JOE54 and European for your patience on helping resolve my issue!!

[EuropeanAM]

Make sure the lower cylinders aren't full of liquid (uncommon but not impossible). Once sure it's not swimming in raw fuel, check everything over carefully for fuel leaks after pumping bulb and after turning key on.

If all is well, see how it does.

NOTE: When priming these systems after servicing, you should always supply PREMIXED fuel from a separate source. Run for a couple minutes- if you didn't open any oil lines or connections the injection system should begin mixing oil in quickly.

[jkscarab]

EuropeanAM "NOTE: When priming these systems after servicing, you should always supply PREMIXED fuel from a separate source. Run for a couple minutes- if you didn't open any oil lines or connections

Per your previous input, I replaced the brass elbow/check valve on bottom of VST (oil feed hose). I noticed the Oil in the hose going to the VST was not full.

I did add ~10mL of 2 stroke oil to the VST tank before closing it up equating to ~50:1. So first startup has some oil.

My plan is to run premix from a small tank and with the oil input hose going to the VST –removed-- I can confirm oil coming out of oil pump... and if necessary bleed (remove linkage arm to oil pump and turn clockwise (service manual 3D-7).

With all the bad experiences mentioned on this forum about Merc oil pump failing, I am trying to be as careful as possible. Seems ensuring the motor is atleast getting oil is one easy thing to to avoid expensive rebuild.

[EuropeanAM]

If it makes you feel any better... about 80% of those "my oil pump failed and blew my engine" were something else. Most engines that fail due to an oil pump failure are quite catastrophic (global damage).

[jkscarab]

So great news is after the above the motor started first turn of the key (ran fresh premix 50:1). So again huge thanks to EuropeanAM and JOE54!!

As I am running premix fuel, I disconnected the clear oil input hose to the VST to easily examine if oil was making it to the VST.
Next as shown in the below pic the oil input to the VST shows the oil hose empty (no oil in hose).

I am looking to bleed the oil line to the VST

The service manual says to turn the screw (blue arrow) shown 3 revolutions to allow oil into the pump.
Further in the manual the instructions state by disconnecting the connecting rod and rotating oil pump linkage fully clockwise allows maximum oil to the VST.

Note the rod is connected to the oil pump via ball/socket as shown.

Question: In trying to push the ball out of the socket it seemed to require a lot of force. Given that this is an old motor 1997 I am hesitant to “force it” and was wondering if there is some better method to get this ball/socket to release? Lubricant or something???

I assume this is a common “bleed” as boats that sit for awhile probably show the same empty oil hose I am seeing so any tips/ideas most appreciated.
Thanks in advance!
oil pump 2.jpg

[JOE54]

i use needle nose pliers pops right off , start engine let it run with oil hose off of vst untill air is gone hold hose vertically

[jkscarab]

JOE54 => "start engine let it run with oil hose off of vst untill air is gone hold hose vertically" Thanks for the input