1979 A4 stopped working

[CVachon]

We have a 1979 A4 that stopped working yesterday. We changed our Racor fuel filter, changed the spark plugs and set the gap, and cleaned the carburetor. While doing this we noticed that the grease fitting for the Oberdorfer water pump had rusted off. Not sure if this is part of the problem.
The engine turns over, but does not start. We checked 3 of the cylinders, compression was 110 on the first and 90 on the second two. We didn't check the last cylinder (closest to the flywheel) because the threads are stripped and didn't want to risk not getting it back in. We checked the points and spark to all of the plugs.
Any thoughts on what the problem could be, or other things to check? Any good A4 mechanics in the Wareham, Mass area? We're thinking about using Onset Bay marina if we can't sort this out.
Thanks in advance for any help you can offer

[Trés 30]

Compression, fuel, spark.

Sounds like you've got good compression, 3 outta 4 ain't bad.

Spark should be a crisp blue snap able to jump ~1/4" to ground.

Gas is fresh and plugs smell of gas and no water in your filter?

Was it a shut down or just wouldn't start yesterday? If shut down what symptoms/sounds?

Might want to service that water pump too

[Mo]

Can you describe how it shut down. Was it sudden like turning off a switch or did it sort of sputter to a stop. A few things you can check. My initial thinking leans toward fuel issue.

Just a couple of things you can check on the fuel side of things before getting too invasive.

[B]EXTREME CAUTION working on a fuel issue. [B] once you open the system the smell of gas numbs the ability of the nose to sense it...

-Fuel...ensure you haven't run out of fuel. Gauges can be faulty...saw two run out of gas this year that thought they had more serious issue.
-Electric Fuel Pump?...if so check wiring and OPSS connections.
-Manual Fuel Pump?...remove oil fill cap and sniff or smell of gas. If there is gas in the crankcase. If so you may have ruptured diaphram on the pump and loosing fuel pressure as well as leaking into the base pan.

[CVachon]

She stalled and wouldn't restart

We've been cruising for about 2 weeks and she'd been running great. She usually starts right up, but it took a few tries on Friday morning when we left Marta's Vineyard. We shut her down when we were out of the harbor, but when we tried to start her a few hours later, it took a few tries again. We were trying to get through the cape cod canal that day, so we decided to leave her on at idle while we sailed for the next few hours. She seemed to be running great, but stalled right before the canal. She refused to restart. We have gas and we changed the racor filter just to make sure it wasn't a problem with water in the gas. When we checked the carberator, it was clogged, so we cleaned it thoroughly. We were really surprised that it didn't restart after we reinstalled the carb.

[Dave Neptune]

CV, have ou been trying to start with the water valve off?

How did the 3 plugs look when you did the compression?

When you reset the gap did you check for spark? And how far off was the gap? And was this "gap adjustment" points or plugs?

Dave Neptune

[Al Schober]

CV,
To determine whether you're chasing a fuel or spark issue, try giving it a shot of starting ether. If nothing, you're missing spark. If it roars for a moment, you've got a fuel issue. Go from there.

[CVachon]

Thinking its a spark problem

We installed new spark plugs and set the spark plugs to .035. We removed water from water lift muffler. Cleaned the carb. Changed the racor. Cleaned the flame arrestor. Changed the oil. We have fuel getting to the fuel pump and the fuel pump is working. We shut the water valve off to start her. She turns over, but refuses to catch. We tried the starting ether, but that didn't change anything. Two of the plugs are at 90 and one was at 110. We can't adjust the timing of the plugs because we can't figure out how to access the flywheel; we have a catalina 30 which has very poor access and we weren't smart enough to buy a handcrank. Based upon what I've read here, it seems that it's a spark problem
We really appreciate everyone's help.

[Mo]

OK, If you have a spare set of plugs try them first....try restart after each intervention. Then points and condensor if you have them on there. It's a pretty inexpensive propositition. Then try it again. If it still doesn't fire up right away, look to the coil. Also have a look at the wires around the distributor /coil and ensure nothing is chaffed there. The little black wire that comes out from under the distributor...ensure it is not pinched and chaffed as well.

After an attempted start have a look at the plugs....see if there is any wetness or droplets on them. Wet looking is gas...Droplets indicate water. What I'm driving at here is that perhaps a progressive manifold leak could have caused the stall...long shot but could happen...you should have noticed a miss...check the plugs and post a phone pic of them if you can.

[hanleyclifford]

Do you have electronic ignition or points?

[Flaky Puff]

Carol's husband

Off the boat having dinner will post pics of the plugs when we return shortly.

[Flaky Puff]

1979 stopped running

We have electronic ignition. Attached is a picture of the old and new plugs.

[Flaky Puff]

Fuel valve needle

Thanks for everything so far should our fuel valve needle look like this? Or should it be an actual point? Does the black need to be removed or should it be there?

[hanleyclifford]

That black stuff is the seal for the needle. It belongs there. Next time call me; I can be on the harbor usually within minutes.

[ndutton]

Just a couple of observations on the direction of this thread:

• Guessing is not troubleshooting. Several posts in and it hasn't been determined yet if the problem is fuel, spark or both. Sooner or later, usually later, by throwing a bunch of parts at it you'll fix it but it can be a confusing and frustrating journey.
  
• About throwing parts at it, I heard another forum member refer to it as "parts therapy" or "change therapy."

Examples of troubleshooting without the parts:

Upon shut down the entire ancillary ignition system could be eliminated by trying to run with a simple jumper wire between batt+ and coil+. If it ran properly with a jumper, the problem is in the ignition wiring and you could stop looking elsewhere. If not, you can eliminate the ignition wiring and proceed downstream to check for a good hot spark across the plug gap.

For fuel, remove the main passage plug and see if any fuel comes out. No? You have a fuel delivery problem that could go as far as the float valve. Fuel comes out but it's cruddy? There you go. Fuel comes out and it's clean? That issue is eliminated. An open float valve would flood fuel all over the place so that's pretty obvious.

Both examples attempt to either indicate a general area that's wrong or eliminate what's right. It's a matter of homing in on the problem(s). BTW, the EWDS monitors fuel inlet pressure and coil input voltage. It would have alerted instantly and indicated which of those dropped below minimum levels had either been the case.

[CVachon]

Point well taken

Neil, thanks for your very honest assessment. At this point, we've removed the carb again because after being taken apart and cleaned on Saturday, it was leaking. We just ordered the rebuild kit from Moyer. So, unfortunately, we won't be able to perform the ignition wiring test until the carb is reinstalled. The gas that came out of the just-cleaned carb was dirty.