Corroded Fuel Line

[HOG WILD]

Hi I am a new Jet Boat owner. I recently purchased a 2005 Duracraft 165xj Tunnel Hull. It has a 60/40 2 stroke merc Jet.
I purchased this boat via private party, from an older gentlemen. The boat appeared to be in excellent condition, and from what I gathered it sat a lot. He claimed he always put stabil, topped the batteries off monthly, etc etc. From all I could tell it was in excellent condition.

Fast forward a couple weeks... I was cruising along at Wot, and all of sudden my rpms quickly dropped to about 4,300 and the engine didn't sound quite right. I slowed down and cked for weeds, in my intake and didn't see anything. I limped on back to the ramp.

After some trouble shooting and hours of browsing forums. I replaced the plugs. No change. I tried sea foam... a little better but no big change. I cked compression. 120 on the first 125 on # 2, and # 3. I cked spark, shocked the s out of myself. So I assumed this was good. I decided to drain the tank, and I noticed a bunch of little orange pieces falling out... Ah hah! I thought I got it fixed. Turned out to be a corroded fuel line. I replaced the fuel line, fuel filter and installed a water separator. I took it out, and ran a lot better, but I still was unable to get to wot throttle with out it bogging out. It seems right around 4300 I can get nice hum, and it appears to be a sweet spot. At around 2000 I get a little backfire or cough not sure which every now and then. I adjust the slow idle speed screws, and it seemed to improve but still does it. It will also sometimes dog out, when cruising at 4300. I adjust the carb mixture again, and was able to get 4,400 rpms, but no more.

I am a noob and am unsure what to do next. I am leaning towards testing the fuel pump, but am unsure as to how to go about this. I also noticed some fuel on the out side of my carbs not sure if this is normal, it was by no means an excessive amount.

I think most of my problems are isolated to the top cylinder. When I replaced the plugs, the top was black and oilie.
When I had it hooked up to a hose out front. I pulled each wire while idoling, when I removed #1 there was little to no change... When removed #2 or # 3 the engine would almost shut off.
Today at the ramp with cowl of I was able to hear a knocking, while it was in idle.

I also think my throttle cable might be stretched and in need of replacement, but I don't believe this is the root of all my issues.

I also wonder if I should drop the impeller and inspect it/sharpening.....it looks ok from a visual perspective.

Any tips or direction would be greatly appreciated.

 

[sixgun86]

I had a similar issue where ethanol had eaten the lining of my fuel line. Those pieces found their way into my fuel pump. Had to pull it apart to remove the debris. Afterward it ran great. If I had to guess some of those pieces found their way further upstream. Be sure the next fuel line you buy is rated to withstand use of ethanol fuel.

 

[Lil' Blue Rude]

Clean out the carbs and fuel pump. Not sure about mercs but I know the omc have a screen filter inside the fuel pumps. STOP running the motor until you do this. The motor is running lean and will blow up if continued. You'll probably need to readjust thhe slow speed idle screw after the cleaning.
If the impeller looks sharp and the gap between the liner and impeller isn't bad then it should be fine.

 

[HOG WILD]

Ok sounds like I'm on the right track. I have been trying to keep my outings, limited to when I change something to see if it makes a difference. Probably going to go tear into it now and See what I can find.

Edit: Ok, I found quite a bit of debri, in my fuel pump, and cleaned it out. Hopefully this will take care of it.

 

[gajet31]

Great post. Reminded me to check my fuel pump for the same thing. I hope you can figure out the problem. These jets can be fickle at times...

 

[HOG WILD]

So I finally got it out for a test run today.

Much improved, I was able to get up to 5,200 rpms.
Ran much better, I did notice how ever there was a little room left on my throttle and if I went for 5,300 or 5,400 is just didn't quite get there and the motor would bog. But like I said there couldn't have been more then a 1/4 inch from full throttle at 5,200 so maybe this is just where this motor is meant to run at. I also haven't tuned the impeller yet, I'm sure that may help a little as well.

I however I am not completely convinced she is running at a 100%

A week or so ago, when I changed the plugs, I noticed cylinder 1 was black and oily. I also did the removal of plug wire test when idling. When I removed plug 1 wire there was no change in the idle, if I removed plug 2 or 3 wire, the engine would die or almost die.

Today when I was adjusting the slow idle adjustment screws, Carb 1 screw seemed to do nothing. I could turn it all the way in or out with no effect. When I adjust # 2 or # 3 carb, there were noticeable changes. I ended up setting all screws at 2.5 turns out. Sound right?

Since I havent owned the boat or motor very long, I'm not sure how its supposed to run. I thought there was a minor bit of delay in power though, when getting on plane. There was a bit of backfiring out of cylinder 1 at around 1500 to 2200. This seemed to disappear once I readjusted the slow speed idle adjustments. The biggest symptom or thing I noticed was once up on plane and cruising speed, it seemed after 30 seconds or so, there was a burst of power. The engine would quiet a bit and lurch forward and seem to accelerate a bit. I am guessing this might be the #1 cylinder coming in. Is it possible that I have a cylinder cutting in out. If so how would I know? I also was wondering is it possible that not all 3 cylinders are supposed to be firing while under idle. I ran it for a good 10 or 15 minutes in the sweet spot. Which was around 5000 rpms, it seemed that the motor performance was improving as time went on. However if I idle down off of plane and got back on it, the engine would be louder once again, and once on plane at cruising speed, and after a little bumping up and down on the throttle I would hear and feel something kick in, the engine would quiet a bit. and I would gain a small minor amount of rpms with out touching the throttle, and feel like I would gain a few mph.

Idk its kinda hard to explain, and I'm a little confused myself, as I am not to familiar with 2 stroke outboards or my boat yet. Let me know what you think.

 

[Lil' Blue Rude]

Check compression. You might have a fuel issue on #1. might have leak some where or it might still be clogged up somewhere. There's alot of small orifices for things like low speed and they're easy to over look when cleaning. You might have a chipped reed or something like that on clyinder #1. Tough to saya put I'd start with checking the compression. Chasing down problems like these can be agrivating some times. Good luck

 

[HOG WILD]

Check compression. You might have a fuel issue on #1. might have leak some where or it might still be clogged up somewhere. There's alot of small orifices for things like low speed and they're easy to over look when cleaning. You might have a chipped reed or something like that on clyinder #1. Tough to saya put I'd start with checking the compression. Chasing down problems like these can be agrivating some times. Good luck

If you look at my first post I already checked compression and it appeared to be good.

 

[HOG WILD]

I will be checking the carbs today, I really think cylinder 1 is running rich. Being that my plug was black, and it only cuts in at higher speeds, plus the backfire.

I think the corroded fuel line problem is resolved.

 

[HOG WILD]

Update:

I have rebuilt fuel pump, replaced air box seals, still no luck, but have seen improvment. Does anyone know if this 2005 60/40 2 stroke mercury outboard, is supposed to only run on 2. The last time I took it out, it seemed to be drastically improved upon accelatration, but still idled very poorly. I have done some work on the carbs, and ran sea foam, and carb cleaners through the carb but still havent had to much luck. I noticed gas seemed to be spitting out of it and am now thinking it may actually be running rich, or have weak crank compression. I will be cking the floats and needles again, tomorrow and possibly replacing them.

 

[jerseyjimk]

I read some where on this forum somebody else was having the same probelm,it ended up being his stator,just a thought.I'm no mechanic myself,but you might want to look into it.Is your #1 plug sparking.That might be why it looks wet.

 

[HOG WILD]

Rebuilt carb, replaced the needle, and cked float. Carb appears to be in good working order. Upon my test run it appeared that the gas spitting out of the carb intake was reduced, but air flow was still coming out. The other bottom 2 carbs are taking air in. The top carb is blowing air out. This cylinder was backfiring a significant amount. I read in the manual this can damage the air valves. If one of these valves became damaged or stuck would this cause air to be blown out the intake. How hard is it to get to the reeds and valves?

 

[Lil' Blue Rude]

I'd say the reeds are the problem. If the reeds aren't sealing that would cause it to spit back out he carb.
The reed shouldn't be to bad to get to. Just remove the carbs and the plate the carbs bolt to house the reeds. Pull the plate and check to see if the reeds are closing. Should't be a very much of a gap betwwen reeds and the plate, might have a chipped one. Get in touch with Chris Carson Marine for a set of reeds. He makes some good fiber reeds and they're cheaper then Boyseen and run better then them to.

 

[HOG WILD]

Yep a whole reed was missing, couldn't find any remains, hopefully my piston has survived. Order CC replacements, gaskets and wash tabs, just waiting on parts now. Hopefully this will resolve the issues. I'm afraid I missed some prime fishing this week.

 

[Lil' Blue Rude]

If it was me I'd pull the motor apart just to be safe. it Could have made it throught the engine without causing damage. I've heard of this happening with another guys merc. It might be stuck some place. Who knows. Hopefullly it did make it through the motor fine put I'd look it over the best I could. You might try to pull the spark plug and see if you can tell if there is any damage from the reed.
I'm not tryin to freak you out about it just showing some concern.

 

[Sawdust Farmer]

You might try to pull the spark plug and see if you can tell if there is any damage from the reed.
I'm not tryin to freak you out about it just showing some concern.

X2

Better to find it now than let it show itself later. What material(s) are the stock reeds made of?

 

[Lil' Blue Rude]

Most stock reeds should be stainless.

 

[Sawdust Farmer]

Most stock reeds should be stainless.

That's what I thought. I think I'd look for it.

 

[HOG WILD]

Its the top cylinder, what would I have to pull apart to look for the reed, I check the crankcase side, and didn't find it. The reeds are pedal style, its about the size of my thumbnail. I guess it could be in the combustion chamber still. Are we talking like pulling the piston out and making sure it isn't wedged in between.

The motor does have low hours on it, Ive ran it quite a bit, testing after I rebuilt something. I kind have a sick feeling I might have broken the reed now thinking in the hindsight. When I first got the boat about a month ago, and noticed it wasn't running right. I think I may have tried to push the red straw on a can sea foam through that reed. I really can't recall, if there was a hole there or a reed. I really had no idea what i was doing. It doesn't make sense that an outboard with low hours, from an old man would have a broken reed. I think it makes more sense that I had one too many beers and busted it. Either way its broken now. My gaskets should be arriving tomorrow and my original plan was to just fix the reeds and put everything back together hook it up to the hose and if it ran fine, I would ck the compression again, if I got the same readings as my previous one. Then I wasn't going to worry about it anymore. However I'm starting to second guess this plan.

 

[HOG WILD]

double cked everything, I can't find it anywhere, the only signs I see of it are some minor scratching on the front of the crankcase, very minor and I don't think this would effect anything. Shined my light thru the spark plug hole for like the third time, took a piece of this weed eater line and poked around inside the chamber, didn't feel or hear anything. Couldn't see anything.

Its either outside the engine or wedged in piston somewheres. But I dont' see any scoring on the cylinder walls. What normally happens when a metal reed breaks off?