Classic AquaSport

Aquasport Mechanicals - things that need a wrench, screwdriver or multimeter => Engines & engine woes => Topic started by: foreverstrung on August 28, 2012, 10:34:17 PM

Title: Engine run and staring problems
Post by: foreverstrung on August 28, 2012, 10:34:17 PM
Hey All. Been a bit. Got a problem here and would appreciate your thoughts.
I've got a '01 Mercury 200 salt water, carbed 2 stroke. The last couple times out I was only at about 60% power. 28 MPH full throttle. should be 45 MPH full throttle. Have not started it for 2 weeks and today it would not spark at all. Checked primer bulb and gas was flowing though bulb never got hard. New plugs 3 months ago. Rebuilt carbs and fuel pump as well.
     Could it be the fuel lines cracked and getting air? How would I check and locate this possible damaged area? If so, why would I not get any spark? Some gas appeared to be getting to the motor.
appreciate ya
Title: Re: Engine run and staring problems
Post by: saltfly on August 28, 2012, 11:19:58 PM
Unplug your cable harness. Then check your spark. Put a remote switch on your power and the other end on
your coil  to use it in place of your harness switch.  If you have spark, which I think you will. Change your starter switch. Think about it. When you turn off your motor. You ground it out. So you get no spark. When a switch goes bad, it either burns open, which won't turn over your motor, or shorts to ground which will let it turn over, but won't give you spark.  If your stator were to keep you from getting spark. The whole stator would have to burn out. Which can happen, but is unlikelly.
Title: Re: Engine run and staring problems
Post by: fitz73222 on August 29, 2012, 02:33:55 PM
Quote from: "foreverstrung"
Hey All. Been a bit. Got a problem here and would appreciate your thoughts.
I've got a '01 Mercury 200 salt water, carbed 2 stroke. The last couple times out I was only at about 60% power. 28 MPH full throttle. should be 45 MPH full throttle. Have not started it for 2 weeks and today it would not spark at all. Checked primer bulb and gas was flowing though bulb never got hard. New plugs 3 months ago. Rebuilt carbs and fuel pump as well.
     Could it be the fuel lines cracked and getting air? How would I check and locate this possible damaged area? If so, why would I not get any spark? Some gas appeared to be getting to the motor.
appreciate ya


Didn't you have this issue a couple of months ago? I thought it was resolved?
Title: Re: Engine run and staring problems
Post by: wingtime on August 29, 2012, 02:43:43 PM
First thing you check on an outboard is spark and compression.  You may have lost a switch pack and were running on only one bank of cylinders.

As for the primer bulb.  Make sure you hold it with the arrow up to be sure the check valves are fully seating.  They don't have springs and rely on gravity.

Salts suggestion of ruling out the key switch is great advice too since they are prone to failure.
Title: Re: Engine run and staring problems
Post by: foreverstrung on August 29, 2012, 11:38:14 PM
Well I went out there today and confirmed I had spark. I'm still not real sure how to check for compression. Never the less, I checked the fuel lines. Hadn't been started in 2 weeks or so and it's been hot as sin here in Texas. The primer bulb wasn't gettin firm so I checked my filter and fuel lines, check valves etc. I think there may have been some blockage in the fuel line between the tank and primer bulb. Disconnecting the primer bulb and pumping it straight from the tank, I was getting little to no gas. I put a hand pump on it and it started flowing. Hooked it back up and it started pretty nice. Let it idle for a half hour or so as I tidied up and decided to take it out and open her up. She stalled 10 minutes out. Sounded rough. Started up again and headed back, (never did get to open her up), stalled again. Started again, sluggishly both times and limped home. My tank is low, I'll go out tomarrow with a portable tank and see what happens.
     If this is the idle/start issue, which I believe it is, great. But I still expect to be at 60% power or so. I do need to check the switch pack, but checking for spark as I turn it over is a 2 man job right? Unless someone has a way they would care to share. Also, How do I check the compression?
Title: Re: Engine run and staring problems
Post by: slvrlng on August 30, 2012, 09:33:16 AM
Sounds like you have crud in the tank. I had a old boat that would crank fine, rev up at the dock, but as soon as you hit a wave of any size all the sludge would get mixed up and it would shut it down. Then wouldn't crank until I cleaned the filters.

Compression is pretty easy to check, basically crank the motor over 4 times without the plugs in. Here is a link to an exact description.
http://forums.iboats.com/showthread.php?t=391323 (http://forums.iboats.com/showthread.php?t=391323)
Title: Re: Engine run and staring problems
Post by: fitz73222 on August 30, 2012, 05:17:44 PM
How did the engine run on a remote 6 gallon tank including a different fuel line? Are you fueling with ethanol based fuel? It is common for older fuel lines to delaminate  internally and break apart causing fuel starvation problems. It may not show up in the filter because the chunks are to large to get into the filter and will lodge at a fuel line connection points and shut the fuel supply off. Your engine does not have switchboxes in the ignition system like older models. The ignition system uses a combination coil and CDI module for each cylinder which was introduced in the '97-'98 model year and has proven very reliable. I doubt compression is the issue. If the engine runs fine on a remote tank with known good fuel then you have a vent problem or a fuel delivery problem in the main fuel system. Lastly, you could have water laden fuel from one of several causes.
Title: Re: Engine run and staring problems
Post by: foreverstrung on August 30, 2012, 10:14:58 PM
I'm not sure of the firing order, but 4 of the 6 cylinders had 60 PSI and the 2 furthast aft, on the motor, left and right, measured 70 PSI. (I pulled all 6 plugs out and checked the compression one cylinder at a time).  I didn't have the right tool to measure the spark, but while idleing, all six plug wires, when removed from the plug, one at a time, gave a nice audible "clicking". Very bright out today. Couldn't see the spark, but I could hear it. Ran it off a porable tank. Dueched the carburater jets with carb cleaner. Put her all back together and let her idle for a half hour or so again. Took her out and on the bay, top speed was only 28 MPH, should be closer to 40 MPH. She stalled. Took about 3 minutes to start her back up and just took her home nice and easy with no issues. Didn't open her up again, but she ran at about 5 MPH with a steady purr, but very reluctantant to hit the gas. Obviously gas is part of the problem, maybe all of it. Does it sound like I might have run some foul gas through the carbs? Maybe let it sit too long, (gas in carbs and fuel lines)? I'm thinking I probably need to rebuild these carbs again and be more careful with my fuel use. Appreciate the help
Title: Re: Engine run and staring problems
Post by: GoneFission on August 30, 2012, 10:39:48 PM
60-70 PSI compression is low for that 2.5L motor.  Should be over 100 PSI - around 120 would be good.  The '91 model 200 2.5 V-6 is considered a desirable motor - the go fast guys find it easy to build up and - as the web site says - scream and fly!   :thumleft:

Sorry to say this, but you've got some problems if 60-70 PSI is an accurate compression number on all 6 holes.    :pale:
Title: Re: Engine run and staring problems
Post by: fitz73222 on August 31, 2012, 05:40:15 AM
I'm kind of suspicious of your compression readings. I personally haven't seen readings that low and relatively even on all six cylinders. Was there an o-ring present on the compression tester where it screws into the cylinder head? Did you hold the throttle wide open when you were doing the test? If in fact your compression is that low, you have a serious problem. Are you sure this engine isn't overheating? Your hot horn or warning module may not be working. When the engine stalls when you are trying to run at high speed, does it just slow down and stop? When you go to restart is the engine turning over slower than normal? Unless your are ready to pull the cylinder heads and physically inspect each cylinder bore for scoring or excessive carbon build up on the piston domes it may be time to get a second opinion from a certified mechanic. As mentioned, carbon build up can also cause low compression like this because the piston rings are stuck and not seating properly against the cylinder walls. This was a huge problem in the 80's when oil companies were experimenting with various fuel dispersants and lots of powerhead failures from coking as a result but its been many years since the problem was widespread.
Title: Re: Engine run and staring problems
Post by: foreverstrung on August 31, 2012, 06:40:32 AM
There is no o ring on the tester, but the presure stayed consistant until I relieved the pressure manually from the gauge. I did not hold the throttle wide open. I hit the kill switch and just turned her over until the gauge quit climbing
Title: Re: Engine run and staring problems
Post by: foreverstrung on August 31, 2012, 07:01:02 AM
Wanted to add.......This stalling issue is new. The last few times I took her out, the top speed was under 30 mph and she never stalled. I've been distracted here for a bit and she sat, unstarted, for 3 1/2 to 5 weeks. Then she wouldn't start and I noticed the fuel line issues and realized my tank was under a 1/4 full, probably pretty nasty. Stalled 1st time with this nasty gas. Stalled yesterday on a portable tank after running at idle speed for near an hour, opened up to 28 mph for about 3 minutes and then it was like the bottom just feel out of it. Started bach up pretty easy within a couple pf minutes and ran at idle speed all the way home, 20 minutes. If it had ovrheated, I'd be surprised that it started so quick after stalling. I'm hoping that I just didn't do the compression test correctly
Title: Re: Engine run and staring problems
Post by: foreverstrung on August 31, 2012, 03:39:08 PM
Someone else asked about "Throttle wide open", when doing the compression check.  If I have the motor in gear at all, which is also my throttle, the key will not engage. Am I missing something here? Can I open up the throttle on a Morse SL3 controler?
    OK Found the manual for the  Morse shifter/throttle. There is a a safety button in the center of the handle which allows throttle without engaging the gears. Used for warming up etc. I'll go run the compression check again this afternoon with this new knowledge and report back. Appreciate the help. Sorry for the appearence of "Stupid". Gotta start somewhere I suppose.
Title: Re: Engine run and staring problems
Post by: Capt. Bob on August 31, 2012, 03:49:27 PM
Quote from: "foreverstrung"
Sorry for the appearence of "Stupid". Gotta start somewhere I suppose.

Not hardly.
The "detent" function of a control comes up quite often on this and every other boating forum on the net.
Now you know. :idea:

Good luck.
Title: Re: Engine run and staring problems
Post by: wingtime on August 31, 2012, 05:37:54 PM
Are you doing the compression test with the motor cold or warm?  You should do it with the motor warm since that will give you a true idea of the compression with the motor at operating temps.
Title: Re: Engine run and staring problems
Post by: gran398 on August 31, 2012, 07:43:18 PM
For peace of mind...as Fitz advises, take it to a shop with certified mechanics. At least you'll know.

You can worry, you can fidget, you can make suppositions, and you can spend money on what is suggested on the internet....Or, you can take it to a trusted local professional and be done with it.

"You can't beat a man at his own game"
Title: Re: Engine run and staring problems
Post by: fitz73222 on September 01, 2012, 06:35:16 PM
I just re read your posts from March. You have the same issue going on or very similar. I was believing this was a fuel issue but since you said you ran it on a remote tank with the same problem plus the low compression it is time to spend some money with a shop. You may wind up ruining this engine fiddling with it for months on end for the sake of $500 assuming the compression reading is false. Take it in and let us know what the problem is!
Title: Re: Engine run and staring problems
Post by: foreverstrung on September 01, 2012, 11:13:46 PM
This is the current plan, takin it in to the shop. I'm just asking for speculation here, but If I had to have this motor rebuilt, what would be a fair price that I might expect from a qualified mech.? I'm figuring at least $500 just for the basic, look see. To put it through it's paces and dial a few things in, If I was lucky, this would be great if that was it, but what would you think worse case senerio would be? In my mind, would be a complete rebuild, how far do I open my wallet?
Title: Re: Engine run and staring problems
Post by: fitz73222 on September 02, 2012, 05:52:54 AM
Quote from: "foreverstrung"
This is the current plan, takin it in to the shop. I'm just asking for speculation here, but If I had to have this motor rebuilt, what would be a fair price that I might expect from a qualified mech.? I'm figuring at least $500 just for the basic, look see. To put it through it's paces and dial a few things in, If I was lucky, this would be great if that was it, but what would you think worse case senerio would be? In my mind, would be a complete rebuild, how far do I open my wallet?


The word "rebuild" is such an ambiguous term these days. The shadetrees consider it a couple of pistons and rings, hone, some new bearings, seals and gaskets and $1500 later you got what you paid for.... As opposed to a blueprinted, line bored, decked, complete machine work, maybe using your rods and crankshaft if in near perfect condition, magnafluxed, assembled and dyno'ed (wouldn't that be nice) for  $3500. You have to decide where to draw the line and where that tipping point is between building a new powerhead and spending $7000 on nice used 3-5 year old engine that may actually have some warranty left on her. The good news is the 2.5 Merc you have is the 350 Chevy equivalent when it comes to parts and expertise out there to really get a good rebuild if you find the right shop. Your engine is still seriously raced and Tennessee seems to be a hot bed of engine builders who really know these engines and can build you a bulletproof 2.5. These guys advertise heavily in Bass and Walleye Boats magazine, which to me is the best publication out there for boat and engine testing ( check it out on line) these guys get into some serious detail where 100 mph is a Sunday drive. Not saying you need to build something that will twist @7500 rpm but you get a rebuild that will last many years backed by a decent warranty. For now, get an assessment of what's going on with this engine from a reputable Mercury dealer (another ambiguous term) and lets make some decisions from there. I can't get my head around your compression readings unless this engine was run without oil or baked alive from overheating. My $.02
Title: Re: Engine run and staring problems
Post by: GoneFission on September 02, 2012, 10:01:11 AM
What the Fitz said...    :thumleft:   Time to call in an expert.
Title: Re: Engine run and staring problems
Post by: GoneFission on September 10, 2012, 03:48:17 PM
Quote from: "fitz73222"
The word "rebuild" is such an ambiguous term these days. The shadetrees consider it a couple of pistons and rings, hone, some new bearings, seals and gaskets and $1500 later you got what you paid for.... As opposed to a blueprinted, line bored, decked, complete machine work, maybe using your rods and crankshaft if in near perfect condition, magnafluxed, assembled and dyno'ed (wouldn't that be nice) for  $3500.

OK - if anyone wants it done, I've got a magnetic particle (MT - often called magnaflux), liquid penetrant (PT - zlyglo), eddy current (ET), and ultrasonic (UT) setup here in the shop.  I could crack check someone's rods, driveshaft, or whatever if you want to send it to me and pay for return shipping.  I can do PT or ET on aluminum; and MT, ET, or PT on steel.  UT is a possibility for any metal, but it's harder to do, takes longer, and does not do a lot better job of finding surface cracks than some of the other methods.  Only downside is you will have to wait until I'm home long enough to get to it.   :shaking2:  No charge to Aquasport members - I don't do this for a living anymore - it's more of a hobby and educational thing for me these days.   :thumleft:  And yes, I know I have some nerdy hobbies...   :tongue:  Send a PM if you got something you want checked.
Title: Re: Engine run and staring problems
Post by: Capt. Bob on September 10, 2012, 06:10:15 PM
Quote from: "GoneFission"
and does not do a lot better job of finding surface cracks than some of the other methods.

Does it work on skulls?
Might help with the sanity rumor going round about Scott and the fleet he's acquiring.
Ya'll goin' to be meeting up for Octoberfest. Some of Lewis' grape elixir should help, if it's uncomfortable.  :scratch:  

I'm just sayin' :wink:
Title: Re: Engine run and staring problems
Post by: GoneFission on September 12, 2012, 08:40:36 AM
Quote from: "Capt. Bob"
Quote from: "GoneFission"
and does not do a lot better job of finding surface cracks than some of the other methods.

Does it work on skulls?  Might help with the sanity rumor going round about Scott and the fleet he's acquiring.
Ya'll goin' to be meeting up for Octoberfest. Some of Lewis' grape elixir should help, if it's uncomfortable.  :scratch:  
I'm just sayin' :wink:

 Not to mention the Life of the Party Margaritas!   :drunken:  We might have to keep Lewis away from those this year...   :jocolor:
Title: Re: Engine run and staring problems
Post by: gran398 on September 12, 2012, 08:52:55 AM
Quote from: "Capt. Bob"
Quote from: "GoneFission"
and does not do a lot better job of finding surface cracks than some of the other methods.

Does it work on skulls?
Might help with the sanity rumor going round about Scott and the fleet he's acquiring.
Ya'll goin' to be meeting up for Octoberfest. Some of Lewis' grape elixir should help, if it's uncomfortable.  :scratch:  

I'm just sayin' :wink:


I'm just now seeing this.

That last one, I picked up for a friend.

Got it?

 :mrgreen:  :mrgreen:
Title: Re: Engine run and staring problems
Post by: Capt. Bob on September 12, 2012, 09:02:17 PM
Quote from: "gran398"
Quote from: "Capt. Bob"
Quote from: "GoneFission"
and does not do a lot better job of finding surface cracks than some of the other methods.

Does it work on skulls?
Might help with the sanity rumor going round about Scott and the fleet he's acquiring.
Ya'll goin' to be meeting up for Octoberfest. Some of Lewis' grape elixir should help, if it's uncomfortable.  :scratch:  

I'm just sayin' :wink:


I'm just now seeing this.

That last one, I picked up for a friend.

Got it? :mrgreen:  :mrgreen:

Well a little birdie told me that a trip out west might be in order to stabilize the fleet then. :wink:

Might want to give the "Icemanbryan" a jingle. :idea:

I'm just sayin'
Title: Re: Engine run and staring problems
Post by: gran398 on September 12, 2012, 09:34:42 PM
Quote from: "Capt. Bob"
Quote from: "gran398"
I'm just now seeing this.

That last one, I picked up for a friend.

Got it? :mrgreen:  :mrgreen:

Well a little birdie told me that a trip out west might be in order to stabilize the fleet then. :wink:

Might want to give the "Icemanbryan" a jingle. :idea:

I'm just sayin'

 :lol:

A trip to the Pacific coast for our AS crew would be "dechit".

We could all meet in ATL, and the group fly out together.

And as you know...it ain't BS :mrgreen:
Title: Re: Engine run and staring problems
Post by: foreverstrung on September 26, 2012, 10:13:09 AM
OK, so here's the update. Pulled it out of the water and scrapped 100 days worth of growth off. Took it into a pro and found that the compression and every other component of the motor appear to be spot on. ( I had a bad compression gauge, obviously). So the growth on the hull was the problem with the speed, Took her out last weekend and she cruised at 40 mph with no problem. The stall issue I believe was a block in the fuel line and a faulty primer bulb, both repaired and no issues.
Title: Re: Engine run and staring problems
Post by: Capt. Bob on September 26, 2012, 01:05:43 PM
:thumleft:  :thumleft:
Title: Re: Engine run and staring problems
Post by: GoneFission on September 26, 2012, 05:06:49 PM
Glad to hear it was not a big mechanical issue.  It was hard to believe that motor would even run with 60 PSI compression.  So take her out and, as the website says, Scream and Fly!
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