A-4 Problem

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J

joefusa

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Nov 5, 2014
73
lockley-newport 23 sarasota
I have a '77 C-30 with the original a-4 gas motor. Having a problem this season that even Don Moyer is stumped. I started up after the winter layup and found some water in the gas. Changed the fuel filter, purged and cleaned the carb with a Moyer kit. Starts wonderfully. Runs like an A-4 should...until I put it into gear. It stalls. Tried goosing it with the choke. No good. Checked the prop and shaft. No Problem. Good spark. Good compression. Anyone out there have a suggestion?
 
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SEMIJim

SEMIJim

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Nov 26, 2010
129
Pearson 30 S.E. Michigan
Does the prop shaft turn freely when the reversing gear's in neutral?

Jim
 
J

joefusa

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Nov 5, 2014
73
lockley-newport 23 sarasota
yes. a diver went down to check things out and other than the usual marine growth, all seems to be okay.
 
SEMIJim

SEMIJim

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Nov 26, 2010
129
Pearson 30 S.E. Michigan
Looking over in Moyer's A4 forums: I can't find a thread that matches. I was hoping to find out what possibilities you'd discussed already.

Jim
 
jrowan

jrowan

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Mar 5, 2011
1,294
O'Day 35 Severn River, Mobjack Bay, Va.
Sometimes you just have to bite the bullet & hire a real marine mechanic to help find the culprit. If you've tried in earnest & already cancelled out the most common problems then maybe U need a lil' help. I say this as a sailor who could waste several weeks of the good sailing season trying to iron out problems, when sailing time is precious. Sometimes it really takes a second pair of eyes to see the problem which may be obvious. But the bottm line is water in a diesel engine is bad, & its no better for a gas engine. Ethanol corrosion is one thing I don't have to worry about with a diesel. But I think your problem is with your transmission binding or the shaft. If the engine turns but the trans & prop don't then work your way down the line till you find the problem.
 
SEMIJim

SEMIJim

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Nov 26, 2010
129
Pearson 30 S.E. Michigan
Thing is, jrowan, the A4 and its reversing gear (that's the proper name for what passes for a "transmission" on an A4) are so bloody simple, that there's not much that can go wrong in there. There's nothing in the reversing gear to bind, if memory serves.

Jim
 
R

rbmcintire

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Mar 11, 2010
292
Catalina Tall Rig/ Fin Keel Deale, MD
Have you have removed the shaft flange from the transmission for a test run without prop load?
 
anchorclanker

anchorclanker

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May 27, 2012
1,152
Oday 222 Beaver Lake, Arkansas
If you had water in the fuel, it likely has some jets and passages in the carburetor that are plugged, or partially plugged. There is something in the modern fuels that reacts with aluminum carburetors, not just the ethanol, that reacts with water and forms all kinds of weird goo's and crystalline gunk. If you catch them soon enough they can often start and run fine without a load, just as you describe. But when you ask for more, there just isnt enough fuel available to maintain any power and they shut down.
 
B

Bold Rascal

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Sep 7, 2011
13
Bold Rascal Pearson 33 Mount Vernon, MD
Hiya Joe,
Youv'e gotten all the water out of your fuel.
Cleaned your carb.
Your Compression is Good.
You Have good Spark. She starts and runs well until you put it in gear?
You have checked your prop and shaft while in neutral and no issues....
Even Mr. Moyer is stumped?

Do you have a manual for the engine? Lots of great trouble shooting info there..
How well did she run in gear before you winterized her last?
Has anything changed since? "Other than cleaning your filters and the carb"
My thinking is you still have a fuel issue which is carb related. Maybe another thorough cleaning and double check your re-assembly.

Have you visted the Moyer Forum to ask for suggestions? It's really an excellent forum...
 
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