23 wonbt rev under load

"I have a 2.3 ford/cobra/omc s

"I have a 2.3 ford/cobra/omc setup in a 1987 17' bowrider. When the engine runs in neutral with no load it sounds good and freely revs up near redline.
However, when accelerating in gear, the engine revs somewhat normally to about half throttle, (which is not quite on plane), and then with any additional throttle input you just get a bogging sound...no more revs or power, (although it appears to have additional fuel available as the accelerator pump seams to still do its thing).

I initially assumed it was a fuel issue, and I went through the filters and carb, but didn't find anything and problem still exists.

I thought if it was electrical, (points/condenser) then the problem would occur unloaded as well, (in neutral). I thought the electrical system worked independantly of load? Am I wrong here?

Any suggestions would be greatly appreciated. I didn't want to just start throwing parts at it without trying to understand what's wrong.
Thanks!"

What ignition parts have you r

What ignition parts have you replaced so far?

"You may want to check the tim

"You may want to check the timing advance in the dist. Under the points plate there are weights and springs, these can rust/seize up or the springs can get loose or break. Timing is much more critical under load than in neutral."

"Thanks for the replys.
I act

"Thanks for the replys.
I actually haven't replaced any electrical parts yet...I guess because it ran fine unloaded.
I replaced the fuel filter, checked all the fuel lines, and rebuilt the carb.

I'll check the status of the timing advance. I see what you mean, an unloaded free reving engine is probably MUCH less picky about timing compaired to full load.
Also, I'm trying to locate points and condenser locally for replacement. Although, would either of these two parts work differently with the engine unloaded/loaded?

Thanks again for your help!"

"Running out of gear only mean

"Running out of gear only means that the system is functioning. An engine can start and run with half the spark plug wires undone. Describe the symtoms. Does it misfire at all, accelerating or at high speed? How old is the Dist. cap, rotor, points, condenser, plugs and plug wires?"

"Not sure of the age of the pa

"Not sure of the age of the parts....I just recently got the boat.

- First time running the boat engine sounded great. (running new gas in new tank) Ran fine at planing speeds for about 30 minutes then broke the alternator belt.....limped home w/kicker motor.
- Second time running the boat was about 3 days later after I took care of the alternator belt. Right off the dock it sounded rougher, and accelerated the boat to full speed with some popping/missing. Ran at full speed with occasional hick-ups for about ten minutes. I slowed down to idle, then tried to accelerate and it wouldn't even plane...it ran up to half throttle then that's it.

I thought I plugged up something in the fuel system so I went through it all and rebuilt the 2bbl Roc carb.

- Third time on the boat had the same problem...wouldn't plane, won't rev past half under load...no power. Runs ok in Neutral. I don't think it popped/missed this time, just no power.

Sorry for the long e-mail....you just never know what detail will help!"

"Troubleshoot the ignition. Ge

"Troubleshoot the ignition. Generally and this time start inside the distributor and work outward. First, check points for obvious damage or malfunction. If you cannot see anything wrong, put in a new condenser and try. If still bad, install and set new points and try. Get back to me on what happens"

Thanks very much. I'll do

Thanks very much. I'll do it.

"Haveing gone through Your thr

"Haveing gone through Your thread I am not sure the ignition is Your problem, but that You overheated the engine when the alternator belt broke. This may have caused a valve failure. Suggest You take a comp test even if getting at cyl4 behind the manifold is a bit tricky, You may need a tester with a flexible hose."

"I replaced the points and con

"I replaced the points and condenser and threw the boat in the water and it ran great. No skipping/missing/popping at all. Full power all across the rpm range.

I ran the boat around for about an hour with stopping and shutting down a couple times...and all the while ran great.

THEN, on my way home as I slowed for a no-wake zone, the engine shut off as if i turned the key off. It easily restarted ran for a couple minutes then the same thing happend....just shut off. This happend a few times as I made my way to the boat ramp.
I'm thinking I must have a broken wire making occational contact? maybe to the coil, or to the distributor?

Morten, fortunatly when the belt snapped I was running without the cowl over the engine, so I noticed it instantly and shut down the engine.

Thanks again for all your help!"

"Fortunately for you the valve

"Fortunately for you the valves don't seem to be the problem. Weak coils, when they don't go out completely, act up as they get hot. If you replace the coil, make sure that you get the right replacement. Some require external ballast and some do not. Check the battery connections, especially clean and briten area where the ground cable attaches to the engine block."

"Hello,
I've been having

"Hello,
I've been having the same problem for days now. After replacing plugs, cap, rotor, points and condenser same thing is still happening. Only suspect as far as ignition is concerned is coil.
I would like to know ED1000, if replacing the coil helped?

thanks"

"Hey MOCO,
I purchased a new

"Hey MOCO,
I purchased a new coil but haven't had the chance to try the boat yet. I'll certainly let everyone know if it resolves the sudden shut down problem.
Last time I used the boat I did notice that the coil got extremely hot even when the engine wasn't running, but the ignition was in the on position....hot enough where you couldn't touch it for more than a second.....so hopefully the new coil will solve the prob.

Thanks....great site."

"Hello,

If you haven't

"Hello,

If you haven't had a chance to try it yet I might surprise you with the good news. I did go ahead and bought a new coil. Tried it and appears to be working. Went boating this past Monday and did not have sudden shutdowns/misfire occurrences.

take care"