fuel line size 1993 200 hp

[newatthis]

Engine alarm went off, slowed down and alarm went off. Took off thermostats and very corroded. Replaced both , therm's, pressure relief valve, installed new water pump.

Engine won't go over 12rpm's on the tach, in neutral over 20 and higher.
Checked heat alarm, alarm works.

Has new Yamaha Fuel/water seperator.

Used Yamaha Carb cleaner, with engine in a water tank.Going to try her out Friday under a load and see.

looking at fuel hoses and primer pump, the hose going to the fuel filter has a slight crack in the outside of the line and the primer pump also has cracks on the outside.

Going to replace both fuel lines and primer pump.

Question? Hose says 5/16 should I be using a 3/8th's?

Yamaha part number is 6y2-24360-51-00 primer pump and fuel hose says Hose L 250.

Thanks so much for all these post, love this place. First boat, been in ocean twice.

[Connley Ho]

Hey!
I have a 91 ProV200 that is doing the same thing that you are experiencing!
I cannot figure out what the heck is going on...although, I have no alarms going off on mine.
It starts alright now that I have done the carbs, replaced the fuel pumps, changed the primer ball AND blew air through the fuel line (from the engine to the tank) I even tried a separate source for a tank....I haven't checked the therms....Let me know how you make out...Oh, a Yami dealer told me that it would be a 3/8's line.

[newatthis]

Check this

Thanks for the interest, I bought a 3/8 hose today with the proper fitting for the water seperator.

One thing I checked was spark.No spark on one cylinder, then I found another without spark, I changed two inginition coils, although I might of just changed the spark plug wire.

For electrical, get a analog old fashion style ohm meter and check your battery for DC volts, the older battery I had was from 2006, the volts read below 12.5, new one reads over 12.5 volts.

Make sure you have spark, read the forum, search year 1991, you might find your model.

If you don't have a manual, buy one and ask a lot of questions. Of course, it might pay to find a good mechanic.

I'm taking the boat out Saturday, I'll let you know.

[Connley Ho]

Thanks bro..I do have the manual and a few good mechanics for friends...looks like it a couple of cases of beer this weekend!
I just bought a 3/8's hose...I can see why you were asking....visibly, without comparing side-by-side it looks much bigger! But the shop where I bought it is authorized Yamaha and they said that the 200's have taken a 3/8's forever...
Spark plug wires will be my next move i guess...
Thanks.

[newatthis]

update

I' always like it when other's keep thier thread going until some conclusion.

So, the problem with low rpm's was the throttle cable, I noticed where the throttle roller was not moving up the throttle cam and sure enough after looking around I saw where the throttle cable was not advancing enough to push the arm foward and thus the throttle cam would not push the throttle roller up, Hope I explained that correctly.

So, took it to the dealer, here in Stuart, fl. after replacing, engine goes wide open, until at 5000 rpm's alarm goes off, tech checks the engine with an infared therm and temp is at 141 at the base of the engine.

When I last had this problem, it ran all morning 10 miles out in rough seas, never getting over 3000 rpm's, when back at the intercoastal, put her up to 4000 and after a minute alarm goes off.

That's when I took out the thermostats and changed them, but was only getting 12 rpm's, ( I assume the cable finally gave out and I chased the problem).

So now perhaps a new thread as I am interested in what everyone who has tried to clean out the water jackets and heads have come up against.

It's about $650 parts and labor to have this done.

thanks for everyone help.