Optimax fuel pump doesn't kick on with ignition

**Radiant** · 01-13-2020, 08:17 AM

I have a 1999 Optimax 200 and when I turn on the key, the fuel pump does not turn on. But, down by the harness there was two purple wires that went into a snap connector, and when I give these two wires power, the relay clicks and the fuel pumps kick on for a couple of seconds. I can hear both high and low pressure pumps. The VST was empty because I just cleaned it. And the filter is new.

My harness is older, from a late 1989 Merc, could this be why the fuel pump doesn't kick on? I had a 150 opti (1999), that had the same issue with my harness, but when I jumped the purple wire to power, the fuel pump would kick on with the key. This 200 doesn't do that, it only kicks on when you jump it to power, the key doesn't do activate the fuel pump.

I also feel like I have an air lock. I only pumped the ball a few times till it got hard, but it didn't seem like enough to fill the VST. When I unscrew the motor mounted filter, a bunch of air is released. I feel like fuel isn't reaching the VST to where the pump can pick it up.

Anyone have any ideas? Optis are new to me

**billybob** · 01-20-2020, 11:58 AM

Yes that is the connector to both electric fuel pumps. More important is always prime fuel system with primer bulb held vertical,[arrow up] before turning key or fuel pumps on. It is not good to run elec. fuel pumps with no fuel in pumps. The fuel lubricates the pump. I also put Premium plus, in my fuel at about 100 to 1 to lube pumps & injectors. Every fall the last time I run my motor. To keep them from sticking.

**Radiant** · 01-21-2020, 10:31 AM

Originally Posted by billybob

Yes that is the connector to both electric fuel pumps. More important is always prime fuel system with primer bulb held vertical,[arrow up] before turning key or fuel pumps on. It is not good to run elec. fuel pumps with no fuel in pumps. The fuel lubricates the pump. I also put Premium plus, in my fuel at about 100 to 1 to lube pumps & injectors. Every fall the last time I run my motor. To keep them from sticking.

So I connect the purple wire to power? It had a cap on it like it wasn’t being used. I did just that on my 150 opti from the same year and it works normally now when I turn on the key, you hear the fuel pumps. But with the 200 i connect the same wires to power and I hear the relay click and the e fuel pumps kick on. But nothing happens at the key when I turn it.

Am I missing something when priming the fuel system? I feel like I have a bunch of air in the system. Only was able to pump the ball 2 times till is got hard. But that’s not enough to fill the fuel filter on the motor and the vst.

Thank you for all the help thus far

**InjectorService** · 01-21-2020, 12:16 PM

When you turn your key on does the buzzer sound? Check if you have 12v power with the key on to the 7 pin harness. Pin to in the diagram below.

**InjectorService** · 01-21-2020, 12:22 PM

This diagram should give you everything you need to know. Power should be supplied by the control box connection (33) down the purple wire. When this happens the relay (22) will click and send power to the little fuse block (13, 14, 15, 16). The power is then sent down the red/black wire to your fuel pumps. You should have 12v power with a key on at the pump connectors.

**Radiant** · 01-21-2020, 02:43 PM

Okay that makes sense. The buzzer does not sound, but I think that is due to age. I will check later and see if I get power at the pin with the key on. Up at the dash, all of my gauges are hooked up to the purple wire and they power on with the key turned on.

Any ideas with the fuel system priming? I feel like I need to somehow purge the air out.

**billybob** · 01-23-2020, 10:50 AM

It,s possible needle or float is stuck in VST. WHAT I would do is, prime fuel line first, prime thru square pulse pump, prime thru w/s fuel filter, then prime VST. it should have drain plug on bottom. Then fill VST. Always hold primer bulb vertical, with arrow up.

**InjectorService** · 01-23-2020, 12:23 PM

Originally Posted by billybob

It,s possible needle or float is stuck in VST. WHAT I would do is, prime fuel line first, prime thru square pulse pump, prime thru w/s fuel filter, then prime VST. it should have drain plug on bottom. Then fill VST. Always hold primer bulb vertical, with arrow up.

Billy, the problem is still that the pumps won't run. They are supposed to run with key on. The float could be stuck but the pumps have to run.