Engine cuts out when boat goes over 30 mph

[clarkc]

This is my first post, and I hope you guys can help me out.<br />I have a 1993 EXCEL 23'SE boat with a 350 engine and a Volvo Penta out drive. The boat starts great, and run great at dock. And it also takes off great, plenty of power. The problem is that when the boat hits about 30 mph full throttle it starts cutting out. Under and around 30 mph boat runs fine. Top end is about 40 mph. I have changed the spark plugs changed the fuel/water filter, rebuilt the carburetor. I am getting ready to change out the points and condenser, and distributor cap & rotor. I have ran it out of gas, and put clean good gas in the boat. It ran fine when I took the boat out of the water in January. I did Winterize the boat for the first time, because it was not in the water for the winter. Am I headed in the right direction? Could it be the coil also? <br />Thanks for your help.<br />Calvin

 

[WSUDERMAN]

Re: Engine cuts out when boat goes over 30 mph

I think you are on the right path. two other areas to check are;<br />1. Timing, make sure it is advancing.<br /> <br />2. Fuel pressure @ the carb.<br /><br />You may want to consider changing the points and condenser with an electronic ignition like Pertronics (sp?) Much less maintenance.

 

[karayj]

Re: Engine cuts out when boat goes over 30 mph

I had the same problem I hope Im wrong check the compression could be a bad head

 

[clarkc]

Re: Engine cuts out when boat goes over 30 mph

Thanks for the replies. I will change out the points, condenser, dist. cap and rotor. And check the compression, have any idea what a good pressure range is for a 350 engine?<br />Thanks Calvin

 

[snapperbait]

Re: Engine cuts out when boat goes over 30 mph

Generally speaking, You should see around 150psi. (engine at normal operating temp) on a healthy engine.. All cylinders should be within 20psi. of each other...

 

[magster65]

Re: Engine cuts out when boat goes over 30 mph

I had a problem similar in a car once that was the coil getting hot and cutting in and out. Maybe try another one 'cause it's such an easy test?

 

[clarkc]

Re: Engine cuts out when boat goes over 30 mph

Thanks for everyone's replies, it turned out to be the fuel pump. I put a gauge in the line and it was only pumping at most 2 pounds. Put the new pump on and got about 10 pounds of pressure. Took the boat out today and it runs great now. Thanks Calvin

 

[karayj]

Re: Engine cuts out when boat goes over 30 mph

I'm glad I was wrong have fun boating 2 more week for me

 

[Bondo]

Re: Engine cuts out when boat goes over 30 mph

I Hope your fuel pressure gauge is Wrong.....<br />10psi fuel pressure is way to high.... anymore than 5/6psi will push gas pass the needle valve in the carb float bowl....<br />You'll be Flooding the engine now, Instead of Starving it....<br /><br />More is Not Always Better....

 

[WSUDERMAN]

Re: Engine cuts out when boat goes over 30 mph

I am glad it's running so well now! 2 psi is way to low!<br />I aggree with bondo, 10 does seem a bit high. If memory serves most carbs will tolorate 8/9 psi and since you just re-built your carb it must be able to tolorate the higher pressure, or like bondo said, your gauge is off.<br /><br />either way, Enjoy!!

 

[clarkc]

Re: Engine cuts out when boat goes over 30 mph

The gauge read closer to 9 pounds and the gauge could have been off a little bit. The pump was a marine fuel pump for the engine, and I took the reading right after I hooked the pump up. I had not even ran the engine yet. So maybe after it breaks in a little bit it might come down a little more. Thanks for all of your help.<br />Calvin