New 43 OMC wonbt go about 2400 rpm why

"I just put a new longblock in

"I just put a new longblock in my 1988 Stingray 190. It has a 4.3l GM OMC Cobra drive. I put new points, condenser, coil, distributor cap, rotor, rebuilt the carb and got it to running.

I took it out to the lake today for a test and it started right up. It ran great all the way to 2200 rpm then it crept up to 2400 rpm and would go no further. The speedo said it was doing about 15 mph. It idles at 800rpm. Oil pressure is perfect, temp is rock solid at 165, volts are at 14.

So what could the problem be? It feels like it's choking out. I tried leaning out the carb a little but that didn't help any. I fiddled with the timing while we had it out and that didn't have any effect. Right now it's a 6 degree BTC like the manual says.

Any ideas? I've worked my butt off on this engine and am so disappointed that it wouldn't even get on plane today. It's got to be something simple, but what?"

check if timing advances at hi

check if timing advances at higher R.P.M. also what carb?

"'New long block', I h

"'New long block', I hope not a car version with car cams, valves etc?"

"The timing seems to advance j

"The timing seems to advance just fine. I had the timing light on it and when I gave it throttle the timing changed. I'm new to this stuff, but it appears to be doing what it is supposed to. How much is it supposed to change when you give it throttle?

It is a marine long block. Specifically for boats. Not cars. I know better than to try to put a car engine in a boat.

The carb is a Rochester 2 barrel."

"Check the anti siphon valve a

"Check the anti siphon valve at the tank top, it sounds like the engine does not get enough fuel. You may even have to have another look at the carb: main jet, float level. Do not lean it out , the valves may be burned!"

"Hi there,
I think I may have

"Hi there,
I think I may have missed something here. You are going 15mph at 2400rpm and its not on plane? I can't see that. Did you check the valve timing with the timing light? Tooth off on the chain? Late valve timing=low power. I'm thinking. If I come up with anything I'll let you know."

I have seen this problem on he

I have seen this problem on here before and no one comes back and tells us what fixed it.

I had the same problem and installed electronic ign. and problem went away.

Mine ran rough when I moved the throttle above 2200 rpm (it is funny how 2200 is the magic number) and would not go any faster(higher rpm). My guess is that the dwell was wrong or maybe a bad condensor.? I'm happy with the elec. ign.

Another post was from Michael Shelby "Is every plug firing?" in the mercruiser section and he didn't give a final fix to the problem.

"Im still thinking about this.

"Im still thinking about this. When I put on the elec. ign. I eliminated the points, condenser, coil, ballast resister from the system. At the same time I changed the leads and rotor. One thing about my engine with the points system is my plug gap was about .020 wider then rec. The elec. ign. system recommends widening the gap some. However even with the wide gap I would think that it would go to full power.

So my unknowns for this problem are:

1. Dwell not set correctly.
2. The ballast resister bad.
3. Bad leads.
4. Bad coil.
5. Bad rotor.
6. Bad points condenser (it seems that this is the first things changed when other people have this problem and it does not fix it).

It drives me nuts that this system is so simple but I can’t find the specific fault."

"It's fixed, but I don&#39

"It's fixed, but I don't know what was wrong with it. I took it to a boat repair place and all they would say was they fixed the ignition. Since I had replaced just about the entire ignition and he didn't charge for any parts, I am guessing it was just some adjustment out of whack.

So I reckon the answer to "what was wrong with it?" is "The boat mechanic needed $220.""