2003 Carbureted Yamaha 150hp

[sutor623]

So, I recently acquired a 2003 Carbed 150 Yammie. Starts right up and runs great. Has had most service done at the shop before I acquired it.

Have a few questions about these motors. How reliable are the oil injector pumps? Should I change the oil hoses when I change the fuel lines? Anything other than basic maintenance (impeller, Tstats, gear oil) that I should consider doing on this girl? I have a factory service manual on the way, just wanted to get some pointers and maybe see the weak points of this particular engine.

Are the carburetors typically a culprit, or are they pretty reliable? I know most people would rather HDPI. Thanks.

I noticed that a new replacement CDI box is $1100.00!!! Sure hope I wouldn't have to replace that anytime soon!!

 

[flyingscott]

It's a wonderful motor. Yamaha hands down has the best oil injection system no need to no need to do anything with the pump. Almost the identical pump and system they used on there snowmobiles since the early 70s that good. You can change the lines get a manual for the procedure to bleed the pump. CDI boxes seldom fail on a Yamaha they have excellent electronics VERY low failure rate. My dad runs an 1985 90 hp never been in the shop for anything other than general maintenance. Carbs are excellent I don't remember if it has Keihin or Mikunis either way excellent carbs.

 

[sutor623]

It's a wonderful motor. Yamaha hands down has the best oil injection system no need to no need to do anything with the pump. Almost the identical pump and system they used on there snowmobiles since the early 70s that good. You can change the lines get a manual for the procedure to bleed the pump. CDI boxes seldom fail on a Yamaha they have excellent electronics VERY low failure rate. My dad runs an 1985 90 hp never been in the shop for anything other than general maintenance. Carbs are excellent I don't remember if it has Keihin or Mikunis either way excellent carbs.

Thanks Scott, good to hear. It sure is a beautiful motor!!!!

Here's the kicker. I have a really nice E-rude 130hp. It is a V4 looper, 1995. Not sure if you have seen my posts on it or not, but I recently put a remanufactured powerhead on the engine. All new fuel lines, carb kits, ignition components etc. Basically the entire engine has been gone through. It has 5 hours on it. It runs great, has plenty of power and idles well. It can be a little finnicky to start sometimes. I like the fuel priming solenoid system, but it seems to me that a motor starts better with a choke. The Yamaha has a choke and fires right up and idles effortlessly. I have to give the Evinrude some throttle and good and warmed up to get her to idle well. But once I do that it will do it for the day.

I have no need for two engines. The yamaha is MUCH prettier and it way better cosmetic shape. The Erude is a little faded, but not bad. This boat calls for a 150hp. The 130's cruising speed is 4200rpms, which makes it a little noisy. The 'rude is also noisier at startup and idle. (The cowling on the Yamaha is MUCH thicker and sound deadening.)

Anyways, one of these girls has to go. I just can't decide which one. Erude hasnt even been broken in yet. I am going to run her all spring and fish so I can further refine my opinion. Which one would you keep? (I am going to run a compression test this weekend.)

 

[flyingscott]

If it was me I would keep them both until the rude is broken in fully. The rude powerhead is newer and parts are cheaper and more available aftermarket for that motor. The yamaha is a yamaha, has more plumbing for the oil injection because you need a lift pump on the tank. You could always break in the rude and then put the yamaha on the boat. That way if you decide to sell the yamaha you can let people test drive it always worth more that way. That will also give you a real world test on the boat which you like better.

 

[robert graham]

Always a good idea to drain each carb float chamber several times a year and especially for extended shut-downs of several weeks or more. Most have a brass hex head drain screw at the bottom/side of the float bowls.....try to catch what comes out in a clean container for inspection.....put rags under during removal so if/when you drop one it won't go down in bottom of cowling.....draining carbs is very good preventive maintenance....

 

[sutor623]

If it was me I would keep them both until the rude is broken in fully. The rude powerhead is newer and parts are cheaper and more available aftermarket for that motor. The yamaha is a yamaha, has more plumbing for the oil injection because you need a lift pump on the tank. You could always break in the rude and then put the yamaha on the boat. That way if you decide to sell the yamaha you can let people test drive it always worth more that way. That will also give you a real world test on the boat which you like better.

Sounds like a good plan to me. Only thing is I have CC controls for the Yamaha so if I put it on the boat I will need new controls.

You are certainly right about the cheaper parts for the evinrude. Those Yamaha parts are SO expensive.

I definitely plan on breaking the rude all the way in before I make a decision

Robert, I run my motors all year. They dont go more than 30 days without being fired up. I normally fish all through the winter also.

 

[robert graham]

I understand but still a good idea to drain your carbs once or twice a year, in your case....when you think about it there's only a few places in your fuel system where water and debris can accumulate....in the fuel tank, in the fuel filters and worst of all the float chambers where they can plug jets causing poor running and worse, lean fuel conditions causing catastrophic engine failure....I assume you also have a fuel/water seperator type filter mounted?

 

[sutor623]

Oh yea always run a racor!!