2005 Mercury 9.9 four stroke

[bluechevyy]

Re: 2005 Mercury 9.9 four stroke

I already cleared those 4 tiny holes. i used a set of fealer guages that just barely fit in those holes and made sure they were all cleared. There was no obstruction and the motor runs the same after that.

The fuel pump is working great. i opened the pump and inspected the diaphram and all is clean and operable. I installed a clear hose from the fuel pump to the carb and it's pumping fuel with no air what-so-ever.

As I was asking before what is to be thought of the top spark plug coming out slightly wet and very carboned up compared to the bottom plug?

Curt

 

[Star]

Re: 2005 Mercury 9.9 four stroke

Bluechevy,
This engine will idle all day long on one plug!!! My engine ran fine on the water and went over 20mph. Could not idle no matter what I did. Therefore I don't think it is a fuel pump problem. The only other thing is the air bleeder goes through a restrictor that may be plugged.
preasure it backwards from that same brass cap you removed. You may have to remove the meter jet to create enough presure to blow it out. If it is plugged you don't get flow to carry the fuel through the idle circuit. The four hole that are under that plate are for the main fuel circuit. Contrary to what you may all think I know this engine and fuel system.

 

[bluechevyy]

Re: 2005 Mercury 9.9 four stroke

I removed everything on this carb, every screw, jet, gastket, everthing, etc. I used the same feeler guages and check as far in as I could on all holes and crevises. I then verified all holes would freely flow carb cleaner through them. I have exhausted the carb. Like I said earlier I cleaned this carb better than anyone could or has. It can't be the carb. It has to be some other function of the engine. Electrical or something. I know it's easy to go back to the carb, but, I promise I have cleaned it THOROUGHLY.

Any other ideas welcome and needed! Thanks again,

Curt

 

[gwukena]

Re: 2005 Mercury 9.9 four stroke

Have you checked your valve clearance?

 

[bluechevyy]

Re: 2005 Mercury 9.9 four stroke

No, and I'm not sure how to do this.

 

[CharlieB]

Re: 2005 Mercury 9.9 four stroke

Check both these links for a service manual

http://forums.iboats.com/showthread.php?t=309079&p=2072211#post2072211

http://1manual.com/Mercury manuals/Service_Manual_Index.html

 

[CharlieB]

Re: 2005 Mercury 9.9 four stroke

The spark plugs should appear the same, the fact that they are not should be checked out.

Using an inductive timing light verify that both plugs are firing.

Switch the plug positions, run the motor and again inspect the plugs to see if the dirty plug cleared up and the 'new' upper plug changed color/condition.

A poor plug or poor ignition coil could cause intermittant firing of as cyl.

Test and repost your findings.

Never ASSUME you know which electrical part may be at fault and replace it without retesting and PROVING the fault as there is NO RETURN on electrical parts.

 

[bluechevyy]

Re: 2005 Mercury 9.9 four stroke

Well, after being told it is for sure my carb on the last 4 or 5 posts from everyone, I did complete a carb dip all parts (completely disassembled) that were not plastic for 22hrs there is absolutely no improvement. So as I have been saying it is NOT my carb. It's as clean as it can get. This is about the fourth time I've taken it out and was sure every time all holes etc were flowing completely unrestricted carb fluid.

The engine starts only at high throttle still and once going smoke pretty badly and surges in rpms pretty bad (I'm guessing around 2k rpms to 3.5k rpms or more all by itself every few seconds.

Any help OTHER than it's my carb would be greatly appreciated.

Thanks,

Curt

 

[CharlieB]

Re: 2005 Mercury 9.9 four stroke

Get the service manual.

Check cranking timing with the spark plugs out and the wires grounded to see what timing is idle and again at WOT.

Advanced idle timing or erratic timing will have an effect on engine speed. In the two strokes, idle speed is adjusted with base/idle timing advance. The 4 strokes are mostly all set electronically, if there is a problem with the ignition module it 'could' affect idle speed.

Again, NEVER ASSUME any electrical parts is at fault without PROVING the fault as there is NO RETURN on electrical parts.

Some model 9.9 4 stroke carbs used an electric coil operated 'enrichener' instead of a choke. As the motor warmed the charging system energized this coil, closing the fuel passage cutting off the additional fuel and the engine slowed to a normal idle speed. Are there any wires to your carb?

 

[carholme]

Re: 2005 Mercury 9.9 four stroke

There is not a free manual available online as yet for the 209cc. The P/N you want is 90-982248 for your s/n as seen in your previous posts.

Here is the Parts List for your engine:

http://www.crowleymarine.com/mercury-outboard/10750.cfm

Gerry

 

[BoatNoobie]

Re: 2005 Mercury 9.9 four stroke

I still say fuel pump.

Or maybe just bad ground. Check all the ground bolts on your block and make sure they make good tight contact.

 

[Mi duckdown]

Re: 2005 Mercury 9.9 four stroke

Not a four stroke person. BUT in your first post you mentioned changing fuel filter to larger size., and it does fill all the way.
Just a thought.
An OEM MERC MANUAL would be my first purchase.

 

[bluechevyy]

Re: 2005 Mercury 9.9 four stroke

Can anyone tell me what my resistance readings should be on my ignition coil. I measured mine using the resistance from the manual that CharlieB posted above ,but, I realize they may not be quite the same. I have a manual coming but of course it will probably be another week or so. My resistance readings for the coil plug wire to plug wire was 8.3 Kohms which is very high compared to the manual posted above and from the ground wire to the orange wire I get a reading of 0.7 ohms which again is very high?

 

[CharlieB]

Re: 2005 Mercury 9.9 four stroke

Rule of thumb for all plug wires is no more than 1K per foot

Many of the 4 stroke twins use a 'dual output coil which fires both plugs together, the arc from one is from center post TO ground as the arc on the other is from ground TO the center post. Both plug fire at the same time, one firing during the exhaust stoke while the other cyl is near TDC of its compression stroke. A poor plug wire can cause strange idle.

If there is room, trim both ends of the wire 1/4 to 1/2 inch and retest as wires can burn a section out if they have been pulled on too hard and cracked the conductor inside. If this cures your readings and idle problems, order new wires.

 

[bluechevyy]

Re: 2005 Mercury 9.9 four stroke

I gave up and took it to a shop (more than likey to get screwed out of a lot of money like always.). Hopefully I will be able to afford to get my boat back when it's fixed.

 

[stormmnv]

Re: 2005 Mercury 9.9 four stroke

get a book on your engine, as this is a possibility.
I had a friend bring me his Nissan ( same engine), one day it ran fine, next day it would not start without primming the carb and opening the throttle, after full set of tests found the valves were out of adjustment.. .No idea how, but adjusting solved the problem '
'

 

[bluechevyy]

Re: 2005 Mercury 9.9 four stroke

Well I'm reporting back with the find that the marine service center found. First I would like to point out the they found the carberator PERFECTLY clean as I reported.

What they found is that there is a casting flaw in the carberator that is causing the float to stick. They attempted to replace the float with 3 others with no improvement. They reported to me that they can fix the problem by hitting the carb and knocking the float loose and it will run like normal. I am replacing the carb with a new one.

I can't beleive I'm having problems with this engine and it's only 6-7 years old. I have to say not impressed with this motor.

 

[Star]

Re: 2005 Mercury 9.9 four stroke

Hi Bluechevyy.
After reading their reason for your carb problem I question their explanation. Carb float systems are very simple, they either are open or closed depending on fuel levels in the carb bowl. Once the bowl is more than half full the engine will run, maybe not well but good enough. It will run until the gas is used up about 1 minute. Yes I have seen float needles stick in the seat if you like to leave your tank hooked up on a hot day with the vent closed. It can deform the rubber tip that is pressed into the brass seat. Under this condition you don't get any gas at all. Your engine always started but wouldn't run at idle. If it sticks open you have gas running out the bowl vent port. Have them give you the bad carb, I bet they won't and I would love to hear their reason.