Engine cutting out

[tootoot]

75 model boat Ford 302(new long block approx 6 hours)new dist (points). First 6 hours, not a hitch. Out running and after about 10 min at cruise (3000 rpm) engine bumped (momentary loss of power) Then OK. 30 sec later bumps got more frequent and got longer periods of loss of power, then noticable loss of speed and power. Powered back to 2200 and was fine for a little, (10 sec or so) then it started again, wouldnt stay on plane. throttled back and idled ok then it quit. Started back and idled ok then had to pump throttle a little to keep it running then I shut it off. Ran for two hours (same gas) on a suzuki 15 4 stroke and it ran fine. I am discounting the distributor as it is new and points were in adjustment, fuel as filter and water seperator is new and kicker motor ran fine, engine and carb because they were also rebuilt, plugs are new also. Here is what is remaining on engine thats old or has not been replaced or rebuilt-- wires, coil, fuel pump. The fuel pump has a very little amount of fuel in the bowl so I am going to replace it. No odor of fuel in the oil. I checked the fuel pump pressure when it was in the old engine and it met specs. Before I pull the pump, I wanted to run this past you guys for some advise. I think it's the fuel pump. Would it act like that?

 

[Mischief Managed]

Re: Engine cutting out

I concur on fuel delivery problems. Might be something as simple as teflon tape blocking the fuel line or a kinked hose though. Would not be the first time something that simple caused that kind of headache.

 

[tootoot]

Re: Engine cutting out

I wish. Been from pickup in tank to inlet of fuel pump. Been searching through the hords of links concerning loss of power and engine missing and its pointing to fuel pump or coil.

 

[daleatskiworldorlando]

Re: Engine cutting out

Hi Tootoot, I run into intermittent coil troubles from time to time. The best way I have found so far to catch this is to zip tie a new coil in and do a quick wire switch when the engine is acting up. If the problem goes away and stays away with the new coil you have found the problem.<br /><br />Hope this helps, Dale

 

[paulie0735]

Re: Engine cutting out

The coil is certainly worth checking, ‘coils ain't coils’ so make sure yours is the correct type for your ignition system. Most will work even in the wrong application for a short time but they will give trouble and quit on you if they happen to be the wrong one for your system, an over heating coil or incompatible supply voltage can give you inconsistent or intermittent spark problems.

 

[Don S]

Re: Engine cutting out

Many times a cracked coil tower will cause exactly the problem you are seeing. The crack will allow it to arc to one of the other terminals and kill the spark.<br />A crack in the tower can be caused by old or defective spark plug wires. So check them also.<br /><br />

The fuel pump has a very little amount of fuel in the bowl so I am going to replace it.

That is not a fuel bowl on the Ford fuel pumps. It's a place to collect fuel incase the fuel pump diaphram leaks. Sounds like the pump also needs replaced, but I don't think that is your cutting out problem. That sounds like ignition to me.

 

[Haut Medoc]

Re: Engine cutting out

Toot, doesn't that bowl say,"if fuel is present, replace pump?"....Or something similar....Start by replacing the pump.....<br />An old coil will show those sort of symptoms....I would replace it too....But, since the coil is so easy to replace...I would do the fuel pump first, take the new coil with you....If you have the same symptoms with new pump & the old coil....Change the coil...Doing it this way will help isolate the cause...<br />The old pump has gotta go if you have fuel in the sight glass.....Make sure that you replace the coil with the proper one.....JK

 

[JasonB]

Re: Engine cutting out

Not to thread-jack, but my 302 is acting almost identically, except it only happens over 3200RPM or so. I have narrowed to fuel or ignition, leaning heavily toward ignition, but haven't had a chance to track it down. Last time out, I ran 15 miles at 3000rpm and it ran perfect. Any time I would bump it to 3500, it would start cutting out.

 

[tootoot]

Re: Engine cutting out

Haut, Thats exactly what I came up with. I want to know what the problem is so next time it will be easier to diagnos. You know, the more I think about it and the way it was acting, cutting out so suddenly and then coming alive again and running so good until the next skip, does sound like ignition. Sometimes just hearing you guys talk helps to "get the feel" for whats happening. Anyways, Ill let you know what happens. Gonna get cold and rainy this weekend so might be next before I can sea (lake) tryal her. Tx Any suggestion on what kind of wires to get?

 

[tootoot]

Re: Engine cutting out

thanks guys. It was my condenser. HT wire off coil had weak spark. Never had that problem before. I didnt realize the condenser ups the energy for the coil putting approx 300 volts to it. I thought it was only to aid in point life. Learn something new everyday.