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Low WOT RPM/engine miss

M

magnum350

Member
I have a 94 Sea Ray 240 BR with a 350 mag and alpha one. According to the tach, it will only turn 3000-3200 RPM's at WOT in gear. It also developed a miss from idle to around 2200 RPM. Not sure if the miss is still present above 2200, if it is its not noticeable. Thinking it may be a fuel delivery issue. Any thoughts?
 
One or more plug wires may be loose or defective. Perform a basic tuneup. Inspect the distributor cap and rotor. Check the condition of the plugs; it should tell which one is missing. Perform a compression test to see how healthy the engine is.
 
Fuel filter was absolutely full of crap. Not sure how it was even running. But I did change it and still the same problems. When I get a chance Ill pull the plugs and check/change them.
 
Your bowl is full of crap also in the carb.

And your tank also.

And your filter that enters the carb in that fitting.

clean carb < Click on this

Copied and pasted here from another site i am the author:

I pumped all the fuel out of my onboard fuel tank when i got it.

You can do one of 2 things, pump the water out of the bottom, or all the fuel out and here is how.

If you just wish to pump just the water out of the bottom of the fuel, you will need to purchase a cheap electric fuel pump from any auto store dc powered.
You will also need about 15 foot of cheap fuel hose from the auto store and clamps to fit the fuel pump.

Install the hose on the fuel pump both ends and cut about five feet on the sucking side of the pump just look for the arrow on the pump.

Remove the fuel pickup tube it's the one where the fuel hose hooks to the tank a 90 degree angel fitting, it's a anti-siphon valve. Unscrew it.

Crank the bow of the boat all the way up, and stick the hose connected to the electric fuel pump 5 feet into the bottom and back of the tank.

Into a clear container pump the water out till you see clean fresh fuel and stop the pump.

Or into a large container pump all the fuel out.

Now check the valve by blowing thru it, check the screen thats its clear.

Install the valve and pickup tube your done.

Question do you have a fuel water separator on the boat, good to have.


Good luck !
 
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Yes it is the spin on type filter/water seperator. I took the supply line off of the carb the other day and I didnt see any type of screen filter inside of it. So I need to pull the carb and disassemble it, and clean it? I'm not good with carbs, so I'll have my uncle do that for me. He is good with quadrajets.
 
Chief
This thread is a classic example of what has been happening lately. Guy answers this person to begin assisting him and here comes Chiefalen to jump in and take over. I know you have the best of intentions but take a deep breath and look before you leap.
 
I like Guy but what did he post that i didn't, did i not post asking if he saw any numbers on it first ?

So now your going to tell me when and when not to post ?

Look at the time line maybe Guy couldn't get back to him has a life i had free time.

Arin;t we all here just trying to help ?

It just happens in the time period that motor was manufactured merc was installing different carbs.

I'm going to let it drop.
 
I used to frequent this forum a lot being a fairly new boat owner and even though I had been in the automotive industry for years, felt there was a lot to learn in marine applications. I found it very good coming here and reading what info and advice the obvious professionals were handing out. Unfortunately this has now become the Chiefalen show and he is drowning out those I came to learn from. I don`t need to learn from a backyard mechanic because I am one. End of story. Out of here !!!
 
I know my way around diesel engines and do decent on gas engines, but these marine engines are a little different, and I'm not real familiar with them. I'm just trying to get help so I can get my boat running good so that I can enjoy the rest of the summer with it. So, if you guys don't have anything useful to add to this thread, then stay out.
 
A note to everyone:

I am not a professional. My knowledge comes from my trouble shooting experience as a U.S. Army radar technician. I worked on two different radars and a battery control center that contolled three radars and a dozen SAM tri-missle launchers. I also repaired the test equipment that was used to test the aforementioned equipment. I spent a few years repairing electric motors, juke boxes, pinballs, bowling machines, stereos and a variety of other electronic/mechanical devices and some gas powered tools. I've only worked on 2 BBL auto/marine carbs.

I have used those experiences to learn by DIY on my former mercruiser engine. Many of the trouble shooting methods for outboards and I/O engines are similar; just simple logic of function, control and operation. I have learned a plethora of information from a multitude of users that have contributed to this website and will continue to do so. Reading repair manuals are the best way I have found to apply trouble shooting logic. To me it's just a step-by-step process of following the procedures in a repair manual along w/the principles of operation.

I believe that everyone has something to contribute. The best thing that we can all do is provide solutions to problems we have solved whether we are professionals or backyard tinkerers. Let's try to respect one another and what they can contribute and not waste time picking at each other.
 
I think I have figured out my problem. Pulled #2 spark plug and this is what I found.

plug.jpg


Now, this is the carb on my boat. It is indeed a Weber, correct?
carb1.jpg

carb.jpg
 
guyjg said:
A note to everyone:

I believe that everyone has something to contribute. The best thing that we can all do is provide solutions to problems we have solved whether we are professionals or backyard tinkerers. Let's try to respect one another and what they can contribute and not waste time picking at each other.
Click to expand...

Noone is questioning anyones right to contribute BUT some feel the need to contribute to EVERY post with unintellagable answers, lack of good english language and most and worst of all NON PROFFESIONAL answers and suggestions some so F'N stupid and many simply copy and paste from other post or web sites. Some are good but TOO many are not and again too many in general.

AGAIN as I have suggested, read, research, THINK, answer with specifics questions and answers..........not just fill every reply box with to much of the time only bull SH!T.
 
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That is a webber. Replace all plugs and make sure they are gapped correctly and retest and report back, May not need carb work....yet.
 
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That info should be on the engine decals........I will look at my manuals later. my first guess would be, for MR43T if that is what I read on the plug in the picture, the gap may/should be .035". Look first at your engine decal to confirm. When I find the info in my manuals I will repost if different.
 
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