Just one more problem... engine stalls in forward gear

[infy]

Having conquered one issue after another... there appears to be one more complication. It lugs and dies in forward. Sometimes it will just barely keep running.

Wide open throttle. Engine to temp.

It seems to rev no problem. Reverse seems okay.

As soon as I shift in to forward it starts to slow down and lug. Usually dies. Sometimes will barely keep running in a zombie state.

There are a lot of threads on this problem... reading them suggests it can be anything. The carburetor, the fuel pump, timing, plug wires, fuel tank, distributor... basically anything on the boat.

Which is a bit terrifying.

Starting with new plugs, distributor cap, and plug wires... I'll report back if I find a fix... suggestions welcome of course

[JOHN COOKSON]

Is the prop clear and free of obstructions?
Also how much sea life has grown on the prop since the last check?

TRUE GRIT

[infy]

I can't tell here... the water is just too murky at the marina. I think it's safe to assume the boat has not left the slip in at least 2 years. I see a ft or 2 of the bottom and it's pretty green and fuzzy down there.

My goal is to make it to the sling under power so I spend as little time as possible in the expensive yard (which to date, would have cost $3,000 if that's where I started)

On the hard I'll do bottom paint, any blisters, and etc... in the slip do diagnostics, waiting for shipping, and mechanical.

I'm a bit of a novice with direct propshaft drives but... would some growth have that much of an affect?

I can turn the propshaft by hand. And it spins freely in reverse... also spins slowly in "neutral" for some reason. I figure if I can turn it by hand the engine should handle it just fine but... maybe not?

[tenders]

Add "blocked exhaust" to the list of potential issues we've seen here with those symptoms.

[pearsontriton28]

I just went through this same issue. I ended up having bad points and chose to go with an electronic ignition. Now, it runs better than ever.

[pearsontriton28]

Add "blocked exhaust" to the list of potential issues we've seen here with those symptoms.

For sure. I had a dock neighbor that couldn’t get his A4 to run well while in gear. He went to an electronic ignition, then a new carb and when that didn’t work, a new A4. Still, it would not run well while in gear. After paying 8 hrs labor to a mechanic to come out and diagnose his issue, they came to the conclusion he had a collapsed exhaust. Essentially he replaced a perfectly running A4 with a new one to fix an exhaust problem.

[roadnsky]

Are you CERTAIN that your plug wires are in the correct order?

[infy]

Are you CERTAIN that your plug wires are in the correct order?

I'm going to check that first.

There's one more thing I should mention... Even after the engine is to operating temp.. about 160* (FWC).. I still have to use the choke to start it. It won't start with the choke in the run position.

[infy]

Holy ****. As soon as I took the spark plug out there was a fountain of water out the cylinder.

It hasn't stopped pouring.

I did not turn it over today... there's still a snowball's chance it's ok...

Corroded exhaust manifold?

[infy]

I would suspect head gasket but... I put antifreeze in. It seems to be raw water coming out.

[JOHN COOKSON]

There's one more thing I should mention... Even after the engine is to operating temp.. about 160* (FWC).. I still have to use the choke to start it. It won't start with the choke in the run position.

Needing brief full choke to start fully warmed up A4 is normal. If a warm A4 does not need some choke to start it means the mixture is to rich.

TRUE GRIT

[infy]

Somehow raw water is going up the exhaust and in to the exhaust manifold. I loosened the flange from the manifold and it drained.

Could be pretty catastrophic... what causes that?

[roadnsky]

Somehow raw water is going up the exhaust and in to the exhaust manifold. I loosened the flange from the manifold and it drained.

Could be pretty catastrophic... what causes that?

Check your exhaust all the way to the water lift.
Your earlier symptoms pointed to a possible blockage as TENDERS mentioned.
That may have then caused your water backup.

[infy]

I'll check on it. I'm also wondering if its because I had the raw water on while turning the engine over yesterday diagnosing other things. I may have filled the exhaust with water and it backed up to the manifold...

[Al Schober]

Welcome to the wonderful and wacky world of waterlift exhausts! They will back up and flood your engine. Hopefully your waterlift has a drain plug - perhaps a valve for draining is in order.
First priority right now should be getting the engine dry. Remove all spark plugs and spin it with the starter. Once the cylinders are dry, a bit of oil in each hole will prevent corrosion of the rings.
Check the crankcase. If the oil is milky, it will have to be changed. High oil level may indicate water sitting under the oil, in which case one of those vacuum canisters can be used to suck out the lowest level stuff which you can examine for water.