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Pra4sno

93 echelon warm start and idle issues

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Pra4sno

First long run of the year today, which is sad!  Made sadder by the echelon giving me my first headache as well.  

Boat:  93 echelon carb'd 350 Merc. With 550 hrs.  

Boat started up awesome this morning and the two times I ran it on the fake a lake in the driveway this spring. 

After pulling my wife slaloming and running some gas through on a longer leg, I switch out and my wife tows me.   When she eases off the throttle for the pick up the motor shudders and dies at idle.  I notice temp gauge never goes over 120.  Sticks there and doesn't move.  Check hoses and water is definitely over 120, but not hotter than normal operating temp.  100% confident this isn't an overheating situation but our skiing is over for the day.  

I get it started again with throttle, but the motor must have quarter throttle and wants to die at idle.  Head back towards launch at a 2k rpm.  Smells very rich.  Get to no wake zone and motor kills out even at a high idle and won't start.  Open box and let it air out for 10 min. 

Through copious throttle and lots of cranking she sputters to life.  Puffs black smoke and then makes the last 200 yards to the dock at half throttle.  Really not happy doing that but needed to get to the dock on my own power as the only other boater in the area refused to help. 

Side note: in over 25 years of boating, giving 10+ tows (some several miles) we got shot down the first time we need help...trying to get 200 yards to the same launching dock.  New 23+ ft "Supreme" surf boat.  Said they couldnt help as they only had an hour to get their kids to soccer practice.  

Motor dies 20 feet from the dock as soon as I come off throttle and I swam the boat the rest of the way.  Load it on trailer.  Engine temp felt normal and not heat soaked.  End up passing the Supreme people up as they are shammying their water spots in the inspection lane.  

I'm leaning towards a very rich condition/flooding issue and am looking for suggestions on what to check.  Going to test my temp sensors as I just replaced the thermostat. 

@Woodski @oldjeep

Edited by Pra4sno

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MadMan

I'd start the boat on the trailer, remove the flame arrester and look down the carb for gas coming out of the bowl vents.

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tex599

Sounds like a carb issue, time for a rebuild. 

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Pra4sno

It starts and runs great until at operating temp.  This indicates to me I don't need a full carb rebuild, but that I have an choke control issue, or an ignition issue.  I'd like to start small as the carb has been flawless and I usually look to myself as the cause of issues first.  I replaced the thermostat and had the housing apart so it's likely I messed up a sensor.

Btw, Distributer and wires are newer.  Points are good.  I certainly have fouled my plugs though so will be replacing.

I think it's the electronic choke control, maybe as simple as it not getting signal from the temp sensor.

Edited by Pra4sno

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oldjeep

What kind of choke is on the carb?

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Pra4sno
1 minute ago, oldjeep said:

What kind of choke is on the carb?

Going to go check, and get a picture right now 

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oldjeep
1 minute ago, Pra4sno said:

Going to go check, and get a picture right now 

If it is an electric heat choke, make sure that you have voltage at the wire on the choke when motor is running. 

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tex599

Another thought, have you checked your ignition coil?  When they start to go out, it can cause intermittent issues, especially when hot. You stated black smoke, which still leads me to believe carb issue. Could be choke as stated above or a stuck float flooding engine. Since you have points, I would also take a piece of sand paper and clean the contacts, check gap and timing.  

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Pra4sno

Ruling out the electric choke, I don't have one :lol:

 

There's a vacuum diaphram control valve.  I took photos but need to upload.

 

Boat firing immediately without issue on fake lake, idling smoothly.   

Went through the entire cooling system just to feel better about it.  All good.  

I'm going to focus on ignition first, checking points tomorrow

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mikeo

I had a '93 Echelon, it was an awesome boat. (someday I hope to see it again) I had my carb rebuilt at ~900 hours, but after some ongoing issues I'm not sure it really needed it. As long as you have a timing light and know how to time an engine, pull the distributor and check the distributor shaft for excessive play. The distributor shaft in my engine had bronze bushings that had worn in to an oval so the rotor wouldn't contact the points correctly. I was trying to order a new distributor shaft when the guy at the local Napa offered to remove the old bushings and press on a new bushing. I was back up an running the same afternoon for less than $2. I figured this out when I was trying to troubleshoot a rough idle with the boat at the dock. Every time I moved from one side of the boat to the other the engine would sputter and then recover. If I didn't rock the boat, the engine would idle smooth. I never had any problems with the boat on the trailer because of the inherent stability.

The engine in my Echelon had 1200+ hours on it when I sold it. There were a few things that weren't perfect, but it ran strong. I replaced the head gasket, heads*, distributor shaft, had the carb rebuilt, new thermostat, and put new springs in the water circulation manifold. All of these were things done in the driveway. 

* I replaced the heads because I thought one was cracked, and I didn't investigate enough before I spent the money (and then it took me longer than the return window to do the work). It was just a leaking/failed head gasket that was causing vapor lock and cooling water to drip down the side of the head. It looked like a crack because the corrosion of the paint, but once I pulled the heads and cleaned them up, there wasn't a crack. Live and learn.

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Michigan boarder

I'd say check your carb linkage, it sounds like a choke is stuck and air is resticted.  Maybe try disconnecting the choke all together?  I haven't had a choke on mine since 2015, the first start is a little tough but then it's fine all day. 

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96Response

To rule out the choke, wait till its a operating temp, take off flame arrester and look to see if the butterfly is wide open. if it is, then not choke related. As far as the coil goes, I have seen them many times go bad and only cause a problem when they get hot. The coil has a tendency to short out when they get warm. Cheap swap out. You can just use any GM 350 Engine coil and pick one up at any local parts store. They are like $20.00 

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Woodski

@Pra4sno:  You pinged me, the comments above are all spot on things to go through to troubleshoot your rich condition. 

Just for clarification - 350 Merc: points and not a Thundervolt IV distributor?  What brand carb?  I would expect Weber (which is similar to Carter AFB or Edelbrock 1409/1410) but could be a Holley?

For some additional troubleshooting - run w/o you spark arrestor for easy viewing that the choke is opening as the engine warms up (it could be the spark arrestor causing the problem also).  You should be able to swing the choke plate easily with your finger, worth checking.  Have you checked point gap and/or dwell, that determines spark strength and timing and would be a substitute cause for what would be a bad coil and poor spark.  If still at a loss, a wild shot, but you might want to then make sure a main fuel jet has not fallen out.

Note: reading back over how the problem was created, was it a sudden throttle cut and a quick slow down followed by the problem, I know you said ease but...(Don't ask her as that may be your last slalom pull, just sayin'?  If yes, maybe a carb float is now sticking due to fuel slosh, shot in the dark but worth a quick look.

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justgary
13 hours ago, Pra4sno said:

It starts and runs great until at operating temp.  This indicates to me I don't need a full carb rebuild... <snip>

OK, how about a "partial" carb rebuild?  Several people have suggested that your carb is dumping fuel.  This is due to one or more of the following: bad float valve, bad float, poor float adjustment, bad accelerator pump, bad bowl gasket, etc.

The engine starts and runs cold because the fuel condenses out of the air and onto the intake manifold walls while everything is cold.  The choke provides extra fuel so that the engine can run properly while this extra fuel is getting robbed from the air mixture.

So at least take the top off of the carb and peek inside.  You'll find a bunch of built up varnish, gunk, and probably even some water in the bowls.  If I'm wrong, just put the lid back on and ignore the fact that you still probably need a rebuild since you are obviously dumping fuel.

Regards,

- Just Gary

 

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Dcurran

I had the same exact problem with my Echelon. Replaced all ignition parts and had the same problem, so I decided a carb rebuild was next (I also had no previous carb issues). When I unbolted the carb I noticed the main gasket had been pieced together by the previous owner so I decided to replace the gasket and bolt it back up. It worked, that was 4 years ago and still running strong.

 

Good Luck

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Pra4sno

Hey All, just reporting back with an update as in my search for answers on the internet I'm always finding threads where the people never reported what their solution was!   Disclaimer: I'm going to leave long posts, and then come back once we track down what is going on to delete out extra stuff to leave relevant info only.  

We have been in the middle of a house remodel and the boat has really taken the back-burner, but I managed to get out with two guys in our skiing crew that know a lot about carb'd boats to start sorting out these symptoms.

1.  First off, we are EASILY able to duplicate this issue.  Super thankful for that.  Boat fires up great when cold, idles perfect, goes into gear and low idles out of the no- wake area really well.  Does first run up to 3k rpm to get us out to our ski spot smoothly, and then starts cutting out as soon as the motor is hot and we try to come back to idle.  Even elevated idle it want's to cut out.  Turning it off and back on after a few minutes requires full throttle to start (flood starting procedure).  We ran it with the engine cover open and spark arrestor off, a well as the engine cover on and spark arrestor on and got varying degrees of this issue, but in both cases we are pretty confident its not vapor lock as fuel lines on motor are cool enough to touch.  Ignition coil was getting very hot, and is original OEM.  They are cheap so I'm going to replace it anyways.  

2.  After checking the ignition system I found some areas of improvement, but none that are causing this issue (but are making it a little more noticeable).  Spark plugs were almost fouled.  Distributor (thunderbolt 12v) looked good, but had very light oxidation so I cleaned the contacts and rotor and used a new gasket.  Spark plug wires are new.  Ignition coil I swapped with a new coil to test that.  I was told by Malibu's support that the coil shouldn't get hotter than the thermostat housing, and mine was really hot.  I haven't run the boat on the new coil yet, but am taking it out tomorrow.  Malibu's staff didn't really recommend any other fixes and said to try the coil first and also hinted towards a carb rebuild.

3.  One of the most technically knowledgeable guys I ski with referred me to Ron Tanis, (owner of Skiboatpartsonline.com and Tanis R&D) and Ron was unbelievably helpful and knowledgeable.  To those who said its a carburetor issue, I hope you know I wasn't intentionally blowing anyone off, just trying to eliminate easier/cheaper items first.  I too am convinced after speaking with Ron that its a carburetor issue.  He said he sees this twice a week in boats of this era and motor combination - the cause is almost always old fuel line not designed for ethanol.  Specifically non-USCG approved stuff without a  E-15 certification on it.  The Ethanol fuel breaks down the inside of the lines into bits of rubber not visible to the naked eye, which he said is attracted to the needle valves and attaches over time. 

4.  When the motor is choked and fuel is cold the motor will run "ok" but when it heats up the needle valve won't seat properly and fuel will flood past right after coming off a run, partially flooding the motor.  When you cut the throttle and go look for fuel flooding in, you many times won't see it happening.  He said to run the boat with the engine cover off and the spark arrestor/air cleaner off, and immediately when coming off throttle after a longer run watch for the fuel trickling out and running down the inner walls of the carb. 

5.  He agreed symptoms are eerily similar to vapor lock or coil issues, but is confident its the carburetor and that a rebuild is necessary.  Cleaning the needle valves isn't a solution he said, as E-15 also causes swelling of the valves over time, so they need to be replaced.  Fuel line from tank to engine hard lines should be replaced with USCG approved line rated for E-15, which fortunately is under 10 feet as it isn't the cheapest fuel line out there.  Switching to non-ethanol fuel without replacing the fuel line won't help if the old fuel line is already degraded, it will just happen again to the rebuild carb after awhile.  My fuel line was replaced by the previous owner a few years ago but NAPA brand non E-15 rated stuff. This advice from him may save a lot of people with ski boats with non E-15 rated fuel line a lot of headaches and money over the years.  

6.  Plug for skiboatpartsonline and for Ron - he's a stand up guy and spent 15 minutes on the phone with me troubleshooting.  Obviously loves what he does and talking about ski boats.  I went over and looked at his website and man I wish I'd seen his prices on ACME props before replacing mine last year.  Insanely good pricing, I haven't seen anyone lower.  He also said he started carrying the new approved fuel line after seeing all of the issues with the old stuff, and its the best price I can find on it.  

Will continue to update and delete non-relevant content from this thread so hopefully if someone has this issue they can find it and trace it through to the solution.  Thanks everyone for the help.  

Edited by Pra4sno

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formulaben
On 6/21/2018 at 4:36 PM, Pra4sno said:

...

Really not happy doing that but needed to get to the dock on my own power as the only other boater in the area refused to help. 

Side note: in over 25 years of boating, giving 10+ tows (some several miles) we got shot down the first time we need help...trying to get 200 yards to the same launching dock.  New 23+ ft "Supreme" surf boat.  Said they couldn't help as they only had an hour to get their kids to soccer practice. 

What a DB move.  Could have been an excellent lesson to the kids in selflessness, but...

 

1 hour ago, Pra4sno said:

Turning it off and back on after a few minutes requires full throttle to start (flood starting procedure).  We ran it with the engine cover open and spark arrestor off and are pretty confident its not vapor lock as fuel lines on motor are cool enough to touch.

You do understand that running it with the cover open could alleviate the heat that causes vapor lock?

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Pra4sno
1 hour ago, formulaben said:

What a DB move.  Could have been an excellent lesson to the kids in selflessness, but...

 

You do understand that running it with the cover open could alleviate the heat that causes vapor lock?

No kidding.  Priorities, right?  

 

I phrased that incorrectly - we checked the hard lines with the cover having been on as well as off.  I just updated the original post :thumbup:

 

The only "too hot to touch" component was the ignition coil (outside of normal stuff like exhaust manifolds, etc).  We let the boat cool for 45 minutes and ran it with the spark arrestor off and the engine cover completely off and duplicated the same hot-start issue, just less pronounced.  

Edited by Pra4sno

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Pra4sno

Got it running great.  I want to say I know exactly what it is (I believe it was the coil as the old coil was very hot after pulling a skier but is now cool to the touch on the same run).  Here is all of what I did:

New ignition coil.

New plugs.

Replaced fuel hose line.

Cleaned distributor. 

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