Engine Talk

[rcnight]

I came across a 1995 Evinrude 150 on the auction site which had a failed "fuel pressure switch". What is this and how does it affect the engine? Thanks for the insight.

[Bigshrimpin]

are you sure it's a 1995? Evinrude has a parts catalog online, but I don't recall any fuel pressure switch on a carb 150 oceanpro.

[gofastsandman]

No such animal. Be wary! A lean condition can be fatal fast.
`89 20sf 96 150 Ocean Pro.

Maybe they were referring to a VRO failure. Lots of failures due to this. Great motors, but the first thing I did to mine was remove the vro and take it to G&S to have George reprogram it. Yeah you burn a little more oil , but it beats hearing BOOOOOM. The oil pump diaphram fails and that`s it.
Get some compression numbers!

[76Red18]

Hey Sandy, Theres a fuel "vacuum" switch on our motors. Tan and black wires, switch is right under the plastic fuel inlet/filter. Seloc manual doesn't say what it does though.

[gofastsandman]

Thanks Red,
My manual doesn`t say either....Maybe part of the smartcraft system?

[76Red18]

From what I've read the VRO is vacuum operated. My VRO was completely removed when I had to replace the fuel pump. The new pump was the non-VRO replacement model but it still has that vacuum switch. Wiring diagram shows the tan wire as part of the VRO and temp circut.

[76Red18]

I cant find a pressure switch. See if you can find out the model #.

[JohnB]

If it is what I think it is, there is a sender switch that checks for restriction in the fuel system, and if you have a restriction, like a plugged filter, it will give you a fuel alarm. I know a guy with the identical motor, and he would get alarms all the time. He took it to the best Johnson mechanic I know, and they changed the switch, filters, and most everything else, tested it with a vacuum gauge, and could never get it to stay off. He pulled the wire, and the boat is running fine, and ignored it.

I have heard of a few other similar stories, and they were never able to get it to stay off, and disconnected it.

[rcnight]

As I mentioned, the engine is on an auction site. Here's the response from the seller regarding my request for misc. engine info: "It runs but rough as it is not getting the fuel pressure needed , if you are to use us here we will install a new switch and motor will be running to your satifacition . all cyl have good compression .believe it is rh rotation , unknown hours but was on a lawyers boat..." Price is below $500. Whata think?

[JohnB]

The lower unit alone is almost worth 500 bucks.