Expert: Everett Peacock - 7/29/2008

Question
QUESTION: Early in the season, I experienced engine cutout after a 30 minute drift over a reef. I had run about 40 minutes to get there at @2800 RPMs. I finally got it restarted and headed back at 2500-2600 RPMS, but the engine cut out after 10-15 minutes. The problem went away, but last weekend, the same problem. This time, I was resetting my drift, and went only a few 100 feet at @1100 RPMs. 5 minutes later, the engine restarted (several tries 3-5 minutes apart) and I was able to go about 15 minutes at @2500-2600 RPMs.

My pre-launch service included a new distributor cap, new condenser and rotor, and new plugs.

I put in a new coil, changed the spark plug wires, and cleaned those connections. I notice in the shop manual that one wire goes from coil NEG termnal to the distributor, and another to the Carb. There are 2 wires to the POS terminal on the coil, but it is very hard to determine their color (too much paint).

I typically top off the fuel after a trip, although not always. I have new fuel filters and fuel/water separator, so I doubt that this is the problem. The starter cranks, and the engine "almost' catches, but will not stay running. Now I cannot even get it started in order to demonstrate the problem.

What would be my next best course of action? I am not a mechanic, but can handle very basic replacements, and have no electronic testing tools.

two years ago I had a similar problem and the diagnosis was a cracked block. There is no water in the oil as in that situation. I think I have outlined all the pertinent information but will gladly tell more if I can.

Thanks in advance,

Tim



ANSWER: do you have a fuel seperator filter on it???? could be water in fuel...when it cutts off do you have spark???need to determine is it fuel or spark...

---------- FOLLOW-UP ----------

QUESTION: Yes, I have one installed. I filled my tank after the new separator was installed during makeready. There was almost no fuel in the tank at spring launch.

I also popped off the distributor and noted a VERY slight bit of carbon on the rotor and each of the terminals: and I mean VERY little, but I wiped it off. I have spark to all 4 plugs. I pulled them all out and there was a VERY slight bit of carbon on each, all were dry. The #4 (rear) plug however showed a bit of 'rust-colored residue' on the ceramic area and there was a bit of what appears to be rust on the metal part of the plug above where the socket wrench attaches.This COULD be due to some water that splashes over the transom from waves. It is usually just a little bit.

When cranking it, there was definitely some combustion as I had exhaust. The engine SEEMS to want to kick over, but will simply not catch.

I will get a new separator and swap out the old one (I understand that one should not simply empty it and reinstall). This does not seem logical as the problem WAS sporadic and went away previously.

If I rule out spark and fuel problems, then I would suspect poor compression, but I have no tool to verify this.

As indicated earlier, 2 years ago I had a similar set of problems and I had to replace the motor: if this one was a candidate for a crack also, then I may have no choice but to retire the boat as newer engines would require refit of the motor munts and 20 year old motors may all be subject to similar problems: do you concur?


Thanks in advance.

Answer
does it have points of not I think it does...set at 28 to 30 degrees dwell  or an pack of matches folded over its abouit .40 /??

ass long as you change the wilter once a year shouldn't have to replace you can dump it out in a glass jar to see any water or particles...so with a water problem you might have to dump it a few times to get all the water out...
it might be worth buying a commpression tested to test the comp so you know that much anyway....comp should be no more than 15 psi difference between any two cylinders i wouldn't worry about the plug deal..it may have jumped timing....