Rough running

[Kelly]

Are you all tired of hearing about my problems? No? Here, I'll try a little harder...

After much discussion, testing and help, and a little bit of "resistance", my coil problems have been solved. At least I think so. Multiple engine running tests at the dock for 3/4 of an hour without any issues led me to schedule a family outing on the boat. One of the largest maritime festivals in Europe takes place every four years here in Brest so the timing was right.

The first time out we decide to just motor around the docks and ogle all the beautiful sailboats. This entails running the A4 pretty slowly, like around 1000rpm for nearly an hour. I was of course very nervous but happy to be out on the water. As we come back into the harbor the engine starts to run roughly and sounds like it's going to stall so I run it in neutral above idle and pretty much coast to our slip. We dock without incident but as I'm securing the lines, the engine stalls.

I was able to restart the engine with no hesitation albeit with subsequent rough running and stalling. After each stall, restarting is easy so I don't think this is coil related (down boys, down). Here's what I've tried since:

During rough running I've removed the spark plug wires one by one and notice a drop in performance each time. All plugs seem to be firing.
Checked the fuel in the Racor filter/water separator: no water and very little particulate matter settles out to the bottom. The gas is clear and yellow. I've never used gasoline with ethanol.
Replaced the secondary fuel filter for good measure.
Removed, cleaned and rebuilt the carburetor using the Moyer Marine kit.
Checked the recent Moyer (Autolite) plugs and all look good (dry with dusty white appearance on the tips).
Adjusted the idle mixture both leaner and richer with continued rough running.

I'm not sure what to do next. I've been wondering about the performance of the generic electric fuel pump (age? functioning correctly?) so I've ordered a new Facet pump for a replacement. I will also replace the distributor cap and rotor as I don't know the age of the cap nor what a bad one looks like. The last thing I can think of is a blocked fuel tank vent. I'll check that this evening.

I'm open for comments. Sure would like to be sailing...

[Dave Neptune]

Kelly, you may be on the right track as a "whitish" plug is a lean one. Re the rough running were you loosing power or was it just running rough? I'd also look at the centrifugal advance to make sure it is free and not stuck. A stuck advance could cause rough running but not usually a stall.
I'll say it again here a cheap fuel preassure gage in front of the carb will eliminate a lot of "GUESSWORK" and wasted "money" as all you need to do is look! Did you try the "playing with the choke" trick?
Kelly, Im heading down to Long Beach this afternoon to get a look at one of my favorite performance projects that I have been following for many years now~the "Hydroptre DCNS". I missed it at Catalina lask weekend when she went for a cruise to the Isthmus and I was just a couple of miles up the island. I had a few friends who were in the isthmus when she was there and they had no idea what or who she was. When I told them they were very impressed especially those who went on line to see what she is about. So cool!

Dave Neptune

[Kelly]

Hello Dave,

Thanks for your ideas and insight.

I'm not sure about "losing power" and "rough running". For me these are pretty much the same. When running rough, changes with the throttle make the engine cough and seem to want to stall until eventually it DOES stall. Playing with the choke didn't seem to help with the rough running but did make the engine change it's "attitude" a bit. This means that I could hear a difference but not an improvement.

As for changing the pump, I don't consider this wasted money for the reasons I stated. I would rather keep an eye on something new during my watch than always wonder about an accessory for which I have no history. I am considering the pressure gage as another add-on.

Hydroptre DCNS: The DCNS is a big employer here in Brest so we're familiar with their projects. One they are pushing now is an underwater nuclear reactor- unlimited cooling water available!!

France's favorite sailing son, Eric Tabarly, worked for a while on the hydroptre project before his untimely death (fell off of a sailboat at night). During our recent maritime festival we had the privilege of seeing all his boats gathered together. They are the Pen Duick series boats. They are all pristinely restored and have amazing stories: Tabarly was a man of "firsts".

[roadnsky]

Originally Posted by Kelly

...As for changing the pump, I don't consider this wasted money for the reasons I stated. I would rather keep an eye on something new during my watch than always wonder about an accessory for which I have no history. I am considering the pressure gage as another add-on.

Kelly-
Sure sounds fuel related.
I agree with you on your feeling of replacing the Fuel Pump.

I'm also with Dave about adding the Pressure Gauge.
Not sure of the availability in France, so I thought I'd point you to a gauge that's worked for me and it's easily ordered at Amazon.

http://www.amazon.com/gp/product/B00...pf_rd_i=507846

Of course I'm not trying to tell you how to spend your boat bucks, just trying to help.

[Kelly]

Originally Posted by roadnsky

Kelly- Of course I'm not trying to tell you how to spend your boat bucks, just trying to help.

Hi Jerry,

Dang, I thought you were going to send me one of those Nevada accessories that never seem to rust- or so it would seem in all the photos. I'm embarrassed to post any photographs of my engine these days. Everything would just look sepia toned.

I'm still looking for the gage...the one you propose doesn't seem to ship to France.

Thanks again!

[roadnsky]

Originally Posted by Kelly

I'm still looking for the gage...the one you propose doesn't seem to ship to France.

Wow, Amazon won't ship INTL?!
Hmmm, damn!
If you're not having any luck finding one, lemme know.
Maybe we can swing something where I order it and ship it to you if it doesn't make it cost prohibitive?

And there are rusty places on my boat.
(Just not as many as some)

[JOHN COOKSON]

Kelly

Are you 100% certain the choke is all the way open? Also is the flame arrestor free of blockage? Just an idea - not calling your abilities into question here......

Here's a way to test to see if you are idling or running rich at low speeds: When the engine starts to bog down shift into neutral and rev it up for 10 or so seconds. This will burn off or "unload" the fuel from a slightly too rich condition. You may see a lot of smoke out the exhaust. This will be a temporary cure until the engine "loads" up again. I used to do this all the time till I got a little less lazy and rebuilt my carb.........

TRUE GRIT

[Kelly]

Thanks for the offer Jerry. I'm off to the boat for some more evening testing. I'll let you know about the results and the gage.

[sastanley]

Jerry...since we are on the Mr.Gasket fuel gauge subject..do they make adapters for the gauge with different sized fuel hose 'barbs'? I just blindly ordered the one you linked to but it is for 3/8" hose, and I am pretty sure I have 1/4".

I get plenty of time to think about it during the day, but a lot of Amazon's content is blocked at work, and then little things like this slip thru the cracks of my holey radar when I get home and have things like slowly-failing/in-need-of-service A/C unit at the house that I am babying until a HVAC guy gets out to see me with 102°F forecast tomorrow.

Kelly, good luck with your testing..should be about 5:00PM your time time give or take an hour and my ability to remember the spread and DST and all that.

Edit - looks like the only one they make..and this item is not returnable..if anyone has 3/8" fuel hose and needs this adapter...mine's for sale...cheap!

link --> 3/8" hose adapter for Mr. Gasket FP gauge

[hanleyclifford]

Kelly - I got tired of wondering if the polishing filter was getting plugged so I moved the pressure gauge around to be right at the carb.

[roadnsky]

Originally Posted by sastanley

Jerry...since we are on the Mr.Gasket fuel gauge subject..do they make adapters for the gauge with different sized fuel hose 'barbs'? I just blindly ordered the one you linked to but it is for 3/8" hose, and I am pretty sure I have 1/4".

Shawn-
Hmmm, I feel bad since I pointed you there.
Is it worth cobbling together a step-down arrangement?

I have one other thought...
Do you want my old Actron gauge? (It does BOTH pressure and vacuum)
I used it for my vacuum gauge until I got the much better MMI gauge.
I'm not sure of the fittings on it but will be down to the boat tomorrow and can look...

[sastanley]

Jerry..I have the Actron gauge..which is fine for now..I still have rubber hose so it bounces around & I use it to measure vacuum.

Don't feel bad about the adaptor..it is there in plain english that it fits 3/8" hose.

I still plan to use the Mr. Gasket fuel pressure gauge and I will put it in between the polishing filter & carb like Hanley..A 1/8" NPT nipple & a 3-way female "tee" with two barbs on it and I should be good to go. I already have those parts laying around. That is next on my project list. I finally "finished" the FWC on Monday evening by draining out the plain water, Permatexing any fittings on the HX that were leaking (most of them), shortened up a few hoses and filled with 50/50 antifreeze. So, it is finished at least until I figure some way to modify it again.

Should be getting dark over in France about now...we should be hearing from Kelly soon..we did a good job of hijacking his thread!

[Sony2000]

Possibly the small jets in the venturi for idling are blocked, or timing is too early, and the points are too close.

[roadnsky]

Originally Posted by sastanley

I still plan to use the Mr. Gasket fuel pressure gauge and I will put it in between the polishing filter & carb like Hanley..

Ok, cool! Whew!

Should be getting dark over in France about now...we should be hearing from Kelly soon..we did a good job of hijacking his thread!

Awwww, let 'em eat cake!

[Kelly]

I'm back. Gorgeous weather here so it's kind of embarrassing to be testing at the dock as everyone else returns from a spin on the water...

Here's how it went last night: engine started up nicely, as usual, and I could immediately hear the rough running I've been suffering lately. I opened the gas tank fill cap with little hope as the rough running was immediate and sure enough, no change.

Then I decided to tweak the idle mixture screw a half turn toward rich (this brought me back to 1.5 turns out from the stop) and the engine seemed to appreciate this by smoothing out noticeably.

Then I ran in gear to get the temperature up and started to mistreat the engine by dropping repeatedly to idle from higher RPM but was never able to repeat the stumbling and stalling episodes I suffered.

I then let the boat pull against the dock lines at low RPM while I washed the deck and then repeated the speed changes. Everything was fine.

So, as usual, I'm at a loss but am wondering if I didn't live through an episode of stuck/sticking valve. Other than some dirt finally working its way through the fuel system, only the sticking valve would seem to be a problem that could "fix" itself.

Comments?

[Dave Neptune]

Kelly, just to be sure, which way did you turn the idle screw, "out" or "in"? Remember in is rich and out is lean, the idle screw controls the amount of air not fuel! Too rich or too lean can cause a rough running engine at idle or very low speed. When I have R&R'd my carb and reset the idle I give the idle screw a slight tweek to lean (1/8 turn or less out) each "new" cold start until I need the choke to keep idling for a couple of minutes until the engine will idle smoothly (around 1000~1100 RPM's)during the rest of the warm up. I find that doing it in this "slow" fashion gives me a rock solid idle @ 700RPM's after a few cold sarts, then I leave it until I need to R&R again. I have done this many times playing with jetting and air correctors quite a few times. The last time was almost 3 years ago and I have not touched the carb since!!!
If it were a "sticky valve" it would be a definate miss when it is sticking~I doubt this to be your issue.

Sounds like you found the problem.

Dave Neptune

[Kelly]

Originally Posted by Dave Neptune

Kelly, just to be sure, which way did you turn the idle screw, "out" or "in"? Remember in is rich and out is lean, the idle screw controls the amount of air not fuel!Dave Neptune

Hi Dave,

I made doubly sure I was getting this right and turned the screw "in" or to the right to have a richer mixture. I like your adjustment routine and will try as you say to make small adjustments until it feels right. Currently, I can stop choking the carb almost immediately after starting.

Originally Posted by Dave Neptune

Sounds like you found the problem.

I wouldn't even dare to think so. I've been chasing problems for so long now that I don't own a sailboat, but rather an A4 testing grounds. Things are brighter though...I motored over to the fuel/pump out dock at lunch today with the engine sounding as smooth as it ever has. Given my history it was a white knuckle ride (I was alone) but everything went well!

Thanks to everyone for all the help.

[sastanley]

Originally Posted by Kelly

...I motored over to the fuel/pump out dock at lunch today with the engine sounding as smooth as it ever has. Given my history it was a white knuckle ride (I was alone) but everything went well!

Thanks to everyone for all the help.

Kelly, You are not alone on this one..every outing is a white knuckle ride for me..I never know when it's gonna quit, although this year she's been quite reliable..:knockwood:

[Dave Neptune]

Fortunatly I was raised to be a mechanic and have worked on all sorts of engines all my life.
I have had 26+ years of service from my A-4 since I got it running. Granted I have fixed a few thing along the way however I have only been stuck once when my "Racor" bowl cracked and I thought I had a fuel pump problem. I wired my extra electric back up FP into the fuel line and still no fuel. By this time the marine hardware store was open so an hour later (2 hours after the initial start and then dead) I was on my way with NO WORRIES. All I had to do was look at the FP gage and not tinker with anything!!!
I take off across the channel at least 15~20 times a year and all I worry about is the beer never the unbelievably reliable A-4 with electronic ignition.

Dave Neptune

[roadnsky]

Originally Posted by Dave Neptune

...all I worry about is the beer never the unbelievably reliable A-4 with electronic ignition.

Well, one must have their priorities in order!

[Kurt]

I'll chime in on the hijacking of this thread as it is interesting stuff! I have never found the A4 to be a white knuckle experience - frustrating a couple of times, but that is about it. During 4 years of hard use and a few long motoring cruises, my A4 only quit on me one time - but then started right back up. That was my fault as I was working on the timing prior to going out and screwed it up. I have had much more experience with old diesel marine engines (growing up on my dad's Newport 41 and actively chartering two different sailboats) and they ALL quit on me and could not be revived at sea. This all being said, I actively maintained my A4 at the dock. I did preventative maintenance work on it frequently (i.e. changing things out that were not bad yet, but towards then end of their useful life) and continually upgraded the engine. I think there is a lot to be said for frequent and diligent maintenance on these old engines. I'm with Mr. Neptune on this one - diligent maintenance = no worries. Most reliable, older marine engine I have ever used - I can't afford the new stuff!

[ndutton]

What year was your Dad's Newport 41?

[Kurt]

Neil - pretty sure my dad's Newport was a 1974 (maybe 1975). It was a Newport 41S - one of the tall-rigged models designed by C&C, but built by Capital Yachts. Although my family did some cruising, my dad and his buddies pretty much used that boat as a race boat. It was named Picaro and was based in San Diego (I think it still is in San Diego, but under a different name now). I pretty much grew up on that boat.

[ndutton]

Ahh, takes me back. Westerbeke 4-107 under the dinette seat, water jacketed exhaust, shaft and prop off center out the port side of the boat, split cockpit, stubby wheel pedestal, double spreader Sparcraft mast. All the 41's built by Capital were 'S' versions.

Capital was located on a residential street in Harbor City, Cal and believe it or not, we loaded the finished boats on the truck with manual labor and two railroad jacks. There was only one location in the shop where the concrete was thick enough to carry the weight of the 41 so that's where it was assembled. The one forklift we had didn't have the capacity to lift the keel so we'd hang 5 or 6 guys on the back of the lift as counterweights. Even then the steering wheels were bouncing, could barely steer the thing so we piled on another couple of guys for stability (?).

Your Dad's boat was built after I'd moved on to Jensen. I was involved with the first three or so 41's built by Capital. Actually that boat was the reason they hired me in the first place. I had pedestal steering experience and up until then none of their other models had wheels.

Good times, yessir!

[roadnsky]

Hey Neil-
Were you at Jensen when they were building Rangers, or had they moved on to Florida by then? ('77-'79)