Unreliable Opti.

redfishm1

New Member
So get this, put the boat in the water and fired up like normal I hit the jack plate button and it died. Tested everything and found low pressure fp no pressure. Replaced all three fuel pumps, fired right up ran for 10 minutes on the hose and turned it off and then no start. Low pressure fp shows no pressure again.
 
Fuel hose collapsing on itself? The priming pump ball collapsing? Clogged gas tank vent?
 
Fished Tampa Bay so you need a jackplate. And yes, I have the same service manual. Showed no pressure at low press schrader, went
 
Fished Tampa Bay so you need a jackplate. And yes, I have the same service manual. Showed no pressure at low press schrader, went ahead and replaced all 3 pumps due to age had perfect pressures for 10 minutes on hose turned it off and no start, no low pressure but vst is full.
 
Why is it on a jack plate? Did you follow the procedure in the manual before throwing par
Fished Tampa Bay so you need a jackplate. And yes, I have the same service manual. Showed no pressure at low press schrader, went
So your original post was worded like your jack plate was part of the issue, which is why (I think) the original question was posed about why it was included in the original post. There’s honestly too many variables to give a magic answer. Also what isn’t clear is did these issues occur before or after the fuel pump changes? From the snippets I would ask:
-What is the quality/quantity of the fuel and the oil in the reservoir?
-What is the age and condition of the fuel plumbing?
-What is your battery voltage reading at the motor? And the condition of the grounds?
-Are the electrical inputs correct, as in relays operating and power and ground making it to where they are supposed to?
-Is the pump running momentarily after turning the key on?
-Will it run manually pumping and pre-priming using the primer bulb? The VST has known issues from age, especially the float and the linkage to the float binding as they get old.

A group response to the above isn’t required I just hope it helps.
 
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So your original post was worded like your jack plate was part of the issue, which is why (I think) the original question was posed about why it was included in the original post. There’s honestly too many variables to give a magic answer. Also what isn’t clear is did these issues occur before or after the fuel pump changes? From the snippets I would ask:
-What is the quality/quantity of the fuel and the oil in the reservoir?
-What is the age and condition of the fuel plumbing?
-What is your battery voltage reading at the motor? And the condition of the grounds?
-Are the electrical inputs correct, as in relays operating and power and ground making it to where they are supposed to?
-Is the pump running momentarily after turning the key on?
-Will it run manually pumping and pre-priming using the primer bulb? The VST has known issues from age, especially the float and the linkage to the float binding as they get old.

A group response to the above isn’t required I just hope it helps.
Optis are very voltage sensitive so at idle the trim or jackplate motor will make the stall if the battery isn't great. Two new batteries went in 1000 mca each. Low pressure at the vst valve, replaced all 3 pumps to make sure. Fired eight up, perfect pressure! Next morning started ro act up and then no start, no pressure. Turns out the aftermarket pumps come with o rings a seals that swell up in gas and the lp pump seal actually split so no lp. The replacement pumps were 200.00, turns out they are junk chinese with bad rubber.
 
Optis are very voltage sensitive so at idle the trim or jackplate motor will make the stall if the battery isn't great. Two new batteries went in 1000 mca each. Low pressure at the vst valve, replaced all 3 pumps to make sure. Fired eight up, perfect pressure! Next morning started ro act up and then no start, no pressure. Turns out the aftermarket pumps come with o rings a seals that swell up in gas and the lp pump seal actually split so no lp. The replacement pumps were 200.00, turns out they are junk chinese with bad rubber.

IMG_20220722_095845551.jpgIMG_20220722_095812787.jpg
 
Optis are very voltage sensitive so at idle the trim or jackplate motor will make the stall if the battery isn't great. Two new batteries went in 1000 mca each. Low pressure at the vst valve, replaced all 3 pumps to make sure. Fired eight up, perfect pressure! Next morning started ro act up and then no start, no pressure. Turns out the aftermarket pumps come with o rings a seals that swell up in gas and the lp pump seal actually split so no lp. The replacement pumps were 200.00, turns out they are junk chinese with bad rubber.
Brutal,

I too have been the victim of chinesium parts.

It’s always easy to say you get what you pay for but a lot of the time the brand name stuff just has a different sticker.

At least you solved your problem

Have a good weekend
 
Brutal,

I too have been the victim of chinesium parts.

It’s always easy to say you get what you pay for but a lot of the time the brand name stuff just has a different sticker.

At least you solved your problem

Have a good weekend
That was the prob finding the pumps, too many times I have bought OEM at crazy prices and boom Made In China on the package.
 
I am not going to link to products but if you have a pump failure and pull apart your VST you will probably find it contains Walbro pump(s) with a roll stamped part number. If you search Walbro and that number on say Summit Racing you might find the same part from the same manufacturer.

Is it still OEM if they make the part for the OEM?

Like a water pressure sensor at 75% less than Merc
 
I am not going to link to products but if you have a pump failure and pull apart your VST you will probably find it contains Walbro pump(s) with a roll stamped part number. If you search Walbro and that number on say Summit Racing you might find the same part from the same manufacturer.

Is it still OEM if they make the part for the OEM?

Like a water pressure sensor at 75% less than Merc
You are an unscrupulous cad!
 
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