High RPM Shut Down

[johnebquick]

I got her back today and took her out for a trial out of Augistine Beach. The motor ran fine but I think I have a fuel delivery problem now. Not as much pep as it did before. Ball is not staying primed. All New lines, water/fuel sep, new quick disconect on tank and prime ball side. I'll check all hose clamps again. I guess i'll try the portable tank also to eliminate tank pickup. Other then that the fuel pump diaphram? ? ? H E L P ! !



P.S. ------------- What about 87 Oct fuel! Could that be it. darn fuel prices!!!


P.S.S. ----------- I also changed prop sizes. I went from a 15x17 alum. prop ---- to a --- 14.5x19SS prop. There's my RPM and sluggish Drop. 2 inch pitch change = a 400 RPM drop. What about prop size 15 ---to a-----14.5. What will that do? I'll Have to put the other prop back on(15x17) alum


P.S.S.S.---------- Should the prime bulb stay rock hard / med hard / or semi hard when running WOT?

[Proheat]

JBQ- GLAD TO HEAR THAT SHE'S FIXED!

ANSWERS:

PS-MOST RECCOMEND 89 OCTANE

PSS-I THINK YOU FOUND YOUR PROBLEM

PSSS- MED HARD TO HARD........WOW- SOUNDS KINDA KINKY!

[flatbottom]

JBQ- GLAD TO HEAR THAT SHE'S FIXED!

ANSWERS:

PS-MOST RECCOMEND 89 OCTANE

PSS-I THINK YOU FOUND YOUR PROBLEM

PSSS- MED HARD TO HARD........WOW- SOUNDS KINDA KINKY!

congrats JBQ

proheat you crack me upz!!!!

[Proheat]

congrats JBQ

proheat you crack me upz!!!!:D

THE HEATS GETTIN' TO ME-LOL

[johnebquick]

When I take here out I need to change one variable at a time. Not sure what to change to correct the problem. I need to slow down!! I'm just too anxious to get out there. I'll add oct boost to the 87 oct fuel, change back to the 15x17 Alum. prop that I just filed down to get the nicks out and check all clamps on the fuel line. Pro Heat, what will happen if I keep the same pitch but change the prop diameter say a 14.5x17 to a 15x17 ? Is there a relationship between RPM and Diameter of prop if the pitch stays the same?
Or is it just what the motor calls for? Does it have to do with speed vrs low end power?

[Proheat]

I HAD FOUND A SITE THAT LET YOU PUNCH IN YOUR BOAT SIZE, WEIGHT, HP AND CHANGE PROP SIZES- LET ME TRY TO FIND IT AND I'LL GET BACK TO YOU.

[flatbottom]

JBQ ...figure out what the boat weight is , then add fuel weight, then add passenger weight, then add fishing gear and coolers with ice weight, if you have bottom paint ask someone here how much it knocks of their WOT. I don't so I leave that out. find your total. Know your WOT RPM Stated by the manufacture. Use the 15/17 to see if you reach the stated manufacture WOT rpm with the weight total from above. If you do (grin) if you don't and are low. Move to a smaller prop size to spin up the rpm needed. If you are high with the rpm and loaded to the gills to kill some fish, move to a larger prop to bring the rpm down. The ball on wellcraft is med/well when under load not well done( sounds better med/hard/ball) LOL today was hooootttttt and air was thin, that could give a 50 or 100 rpm loss/with 87 if the tach is right on !!!!. after you figure it out, go catch some da'um fish man

[johnebquick]

Remember when you were younger and you went to the local fair, Paid a quarter and took three wacks with a sledge hammer at an old auto. I'm there. I have had a alarm buzzer problem sence I bought the boat. A ground that I have been chasing now for three weeks. It comes and goes along with all the other problems in this outboard. With the key in and on, the alarm buzzer sounds and wont shut off. When disconected form the block and reconected, the problems goes away. Most likely a warn wire going to ground S O M E W A R E . Wed when I took it out, the ground acted up again so I pulled a wire on the buzzer. After running about 15 min with no problems it went to about half throtle. 2500 rpms. Is this the shift switch that Barnacle Bill stated or as I read ,now this gets complacted, when running with a VRO, if the alarm buzzer gets too much voltage it will send out a false alarm and activate the S.L.O.W. witch in turn shuts down two cylinders and only operates mid throtle and under to protect the motor. Does this motor have the shift switch and or the S.L.O.W. INSTALLED? A'm I looking too much into this? I just want to fish. I don't need another project. HA! HA! I think it's too late !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[barnacle bills marine]

When you state you take it off the block are you talking of the brown wire off he cylinder head??? If so you may have a bad temp sender or the enigne is getting to warm.

By pulling the wire off the buzzer you killed your warning system. When these engines go into SLOW it will cut down to about 2500 RPM's. Im guessing you have a bad sender or a engine that is getting hot.

[johnebquick]

Yes thats what I ment. I am going to take it out Sat afternoon with my father and one at a time disconect the temp sensors. What I ment to say is that on land with the motor dead cold and turning the key to on is when I get the buzzer. I dont think the motor is getting too hot. I'm worried about the VRO giving a false trip from the ground either on the temp sensor, the VRO sensor, or a ground in the buzzer itself. But last time I took the tan wire off the cylinder head and reattached it, the problem went away for a day. Do you think the wire has chafed and by moving the tan wire I temperalry ungrounded the problem, or am I barking up the wrong tree? I also want to state that this year motor has only one switchbox for both the port and starbord side. Does it also only have one temp sensor? I have a basic manual for this motor and it only covers the engine with two switchboxes. How do you test the VRO system anyway? And thanks a million Barnical Bill for all the info. I'm really trying to work through this myself. It really helps me learn the motor for furture use.