Noisy Starboard transmission...rich engine

[405driver]

Thanks for the replies.

I changed both port and starboard fuel filters today. I poured the contents from each filter into separate glass jars. The port appears to be clean gas, the starboard has no fuel/water demarcation line, but is definitely lighter in color. The fuel came from the same pump only minutes apart. I am including a picture for your opinions. Port is on the left, starboard (problem engine) is on the right.

All opinions welcome.If it's water, this may be the root of the problems with this engine.

Thanks

[405driver]

Here's more.....Today I took the fuel samples to the offices of our local fuel distributor to get their opinion. After a through examination and a lot of discussion, it was determined that there is no water in the fuel. So, here we are again, what is going on with this engine?

Tomorrow we are again going to put a fuel pressure gauge on the engine while actually running the boat. Sounds like a fuel pump but earlier fuel pressure checks seemed to be normal.

Anybody have any experience with a failing fuel pump? Can it quit and then start again. Seems to me if it quit it would "stay quit" but at this point I'm not going to rule out anything.....

Thanks

[Viper]

Is the fuel pump loud and have a wining sound? Any different sounding than the other engine?

Are we still talking about a noisy tranny and a rich running engine?

Has anybody put a vacuum gauge on this engine? Has a leak down test been performed yet?

[405driver]

Viper.....yes, same thread, same engine. No leak down test, but did do the compressions 165=170 each engine. There is no smoke coming from the exhaust but I agree, probably should do a leak down test. However, It doesn't seem to me that a cylinder problem would cause it to simply quit and not restart....then restart later. Vacuum is another issue and could cause that problem I suppose if it's giving the computer the wrong info.

Beats me.

[jcoll]

I've just read most of this thread. Found it quite interesting. It's been a week since your last post but if you haven't fixed it yet my advice would be to sink the boat but that's probably bad advice. Based on the history here, I think this is unrelated to previous problems you've had. I would think an immediate cut out and later restart is a high probability of ignition failure. It must be determined what system is failing, ignition or fuel, when the engine has shut off. This would be best done with 2 people, one to crank the engine and one to do some quick tests. With a screwdriver and access to one plug wire you could check for spark while someone cranks the engine. Insert the screwdriver in the end of the plug wire once it's removed from the plug and hold it close to the exhaust manifold. Watch for a spark to occur periodically while cranking the engine for about 30 seconds. If you get spark then fuel system checks are in order and engine management system is possibly contributing to the problem. If the problem is intermittent it can be difficult to get to the root of the problem. If it can be repeated consistently then the solution will be easier to find.

[waybomb]

If rather see an inductive light used to check current in plug wires than use an open spark

[Viper]

If rather see an inductive light used to check current in plug wires than use an open spark

+++1
or get a proper marine spark tester that takes this into consideration.

[jcoll]

waybomb wrote:
If rather see an inductive light used to check current in plug wires than use an open spark
+++1
or get a proper marine spark tester that takes this into consideration.

Yes you are both correct - safety first. It is a gas engine and it is a confined area so best not to have open spark occurring. Hopefully he'll find direction to the correction of the problem with this test.

[Mikwallace]

Well, this is a seven year old thread. I read it word for word from the beginning with great enthusiasm! The owner was making follow-up post so progression could be seen.

Then all of a sudden it (postings) died!

Did 405Driver take jcoll’s advice and sink it? Probably not.

Does anyone have contact with the op and know the resulting outcome?

I’ve the same boat with same engines and really curious as to the outcome!!

This forum is full of great boaters and highly experienced mechanics.