Possible Bad Fuel Pump ??

[rpatton]

1999 Johnson 90 hp. Motor ran great all weekend . Sunday took it out and ran wot for about a mile and then it just died like running out of gas. tried to start it and it would fire and die, fire and die. then I checked the primer bulb, and it felt about half full so I pumped it up and then it fired and ran wot for about 50 yds and died again. bulb was half full again so I pumped it up and it ran great for 50 yds then as it started to die we pumped the bulb and it came back to life and stayed there if we would pump the bulb every few seconds. Im thinking fuel pump but just do not want to throw parts at it. is there any other thing that could be causing this issue.

 

[gm280]

Oh yes it surely sound like time to either rebuild the fuel pump or replace it. Not hard to do either. Buy a fuel pump rebuild kit (they're cheap) and replace the few parts and happy boating again... JMHO!

 

[rpatton]

Thanks for the reply but a 99 is a VRO motor. and I am told they are not rebuildable, you have to buy a replacement part. they are very exspensive so is there a way to bypass the vro pump with a old style. I am premixing my gas anyway

 

[racerone]

?????----Step # 1 would be to take the VRO apart for inspection.---Fuel piston repair kit is available at $ 70 or so..-----If the pump is ok then look for other problems.

 

[rpatton]

local Johnson dealer says that there are no kits available. so they say?? thought I read on here somewhere that you can replace the vro with a standard Johnson pump .

 

[racerone]

?????----Would you like the part # for the repair kit ??--Dealers / front counter are not always well versed in stuff like this !!

 

[rpatton]

ah ,yea if you got it. thanks. I would really just like to get rid of it all together though. I am pretty sure it can be done but now exactly sure how. the secret section tells you how to bybass it but not how to replace it.

 

[racerone]

Part # is 436095-------Myself I would go to a parts bin and install say a pump from a 1966 model 100 hp.------Ultra simple and very reliable too.

 

[Tim Frank]

I'd do a pressure and suction test on the fuel system.
That will tell you exactly what is wrong.

 

[rpatton]

I wonder what kinda lines I will need to deal with. will the bolts line up with the vacumn ports

 

[Chris1956]

The VRO Pump (really called OMS Pump) works in conjunction with the vapor separator and vapor pump to supply fuel to the carbs. It makes sense to check/rebuild those components, before replacing/rebuilding the OMS pump. Also check the pulse limiter and pulse lines.

I would recommend a factory service manual as well. The maxrules web site sells the OMS rebuild kits and replacement fuel pumps. I have heard they are not the cheapest.