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No top end.

Since it used to run fine there is no need to change jetting. You need to index flywheel and check timing on each cylinder as a slipped hub magnet can cause this and its a common problem.
 
Well i bought boat used 96 290fs stratos with evenrude 225 and i have noticed that there i a peice of wire with 6 jets on it and is wraped to a hose on the carb. The boat was new in WV and went to Harrisburg PA and now i have it in the mountins of PA. Im 3rd owner. But last fall I had it out 1 time before I put it away and the boat ran great. Wot was 52mph and 6200 rpms. All winter i was looking to buy different prop and i got it out this spring and cant get more than 47mph and 4800 rpms . If i trim more i only rev to 5100 rpms. Changed power pack. But not much change. Did some oms tests can seem to find the problem.
 
Ok looking at the motor from the rear where is #1 cylinder. Top right or top left. And do they run 1,2,3 down or 1 left, 2 right, 3 left 4 right to 6?
I found that if i put timing marks to tdc the top right cylinder is tdc. Shouldnt it be top left?
 
What are the compression numbers is the first part of troubleshooting and please check the jet sizes. Harrisburg is close to sea level you may have the proper jets already in it but there is a reason the extra jets are there. My guess is the previous owner was running at different elevations as well. Get a can of seafoam spray and give it a good decarb after you do the compression test and see if the numbers improve. After 1 year running rich the cylinders and rings are likely loaded with carbon buildup just look at the top of the pistons and see if they are black?
 
Ok the #1 cylinder is right top and is correct for timing marks TDC. The cylinder that I was having trouble with was #5 with old power pack. New power pack seems to have helped that plug. And now is brown in color. But still no top end. I used a scope to look i all cylinders and they all look good with very little carbon.
 
Ok, you have all 6 firing, that potential problem is ruled out.

Remove the throttle cable from the engine linkage (3/8" nut) so that you can operate the throttle at the engine and watch the mechanism.

Engine off, slowly advance the throttle linkage watching the operation. You will see that two things happen....throttle butterflies open, and timing advances.
When you get to WOT, the throttle butterflies must be horizontal in the throttle body throats, AND the timing must be fully advanced.

Timing is advanced as the timerbase rotates counterclockwise under the flywheel.

At WOT, the timer base movement will be halted by the WOT stop screw and rubber stop bumper. You can visually see all this under the stbd side of the flywheel.

It is a very easy task to visually inspect the timerbase movement and make sure it is advancing all the way. It could be sticking, and if so, you will never get full RPM.

WOT timing spec is 18* BTDC if you want to hook a timing light up and check it at WOT.
 
Ok will check linkage. I do know that butter flys are all closed and at wot they are all perfect horizontal.
Dose the fuel pump suck enough pressure to maybe suck fuel inline shut on a weak fuel line bend at wot? Is there that much sucksion?
 
Yes there is enough suction to collapse a fuel line. There is a vacuum switch on the incoming side of the pump to set off a warning for just that issue.
 
Sure. Can happen. The OEM fuel lines on that engine were pre-formed lines with proper bends that should not collapse.
But weak line walls over time, someone replacing lines with non-OEM line, all that can factor in.

The pre-formed lines generally are not available anymore, so be careful when engineering a replacement that you do not create a restriction.

From the fuel distribution manifold to each carburetor I use that yellow Tygon fuel line, for example.
 
Only the fuel line coming from tank to the fuel pump seems to have a weak wall just inside the engine cal on a 90 bend about 5" from fuel filter. I think I can get away with just cutting that section out if there is enough extra line. All other fuel lines look to be in really good condition.
 
Remember....suction / vacuum problems will ONLY occur on the fuel tank side of the fuel pump.
The output of the fuel pump is pressurized fuel supply, and will not collapse a line.

You should seriously check that fuel vacuum switch while you are in there. It is located on the fuel pump (VRO) bracket, is usually white body, and has a fuel hose going to it, as well as a connector with a black wire and a tan wire. Tan wire will have a color tracer. Don't remember the color....sorry.
 
Nope. There is no way to "push it in" or manually operate it.

Proper way to check it is key on, apply vacuum to the small fuel line nipple on the switch, alarm should trigger when max vacuum spec is reached.

Again, I cannot remember the spec off the top of my head. I remember fuzzy somewhere around 7....now 7 what? 7 inches of mercury, 7 inches of water...I would have to look up the spec.

When alarm triggers on a '96, the only thing that will happen is the check engine light on the tach will come on.

ON A 96 and above Systems Check engine, the audible warning horn WILL NOT SOUND unless the engine is running. If engine running, then the horn sounds for about ten seconds, shuts off, and the operator is supposed to check the tach for the warning light.
 
I checked it and engine light came on and alarm so i guess its working proper. I put new Champion QL77JC4 plugs in and I checked linkage for timing advance and made sure it was working. I cut 6" OFF fuel line to elimnate bad 90 deg bend. Now I have to wait till tuesday till I can test on water. I dont need a speed boat I just want it to work proper! Uggg tired of playing with it. Just want to fish. Waleyes are on like fire right now at my lake. I fish then mess with motor. But sould be fishing more.
 
Went for a test run today. Not good. 1996 Evenrude 225 still no top end rpms. The engine ran with a miss and suger all day. I backed it into a dock to check spark plugs. As it sat there ideling ruff and chughing once in awhile I noticed something different. The exaust ports on each side of water discharge (pisser) that water would chug out of the exaust port holes the black smoke for a second. Can anyone tell me that this is normal?. Or do I have a head gasket or cracked block problem. How to check without take off head? I have done a compressing test on all cylinders and all check out to be 100 to 116 psi. Help!!
 
You need to get the compression numbers more even first off. A good decarb may take care of it the numbers are a little over 10%. Have you done a spark gap test with a open air spark gap tester? It must jump a gap of at least 7/16 inch brite blue snap on all the plug wires. Confirm the compression is even and the spark is correct then you can go from there. Call seaway with your model number and see what jets they recommend and you can also try different plug gap, all motors are a little different depending on application. I recommend the champion plugs and just change them at least yearly. NGK suck in my opinion. We now know the compression is unacceptable troubleshooting allways goes in order compression, open air spark gap, sync and link, then fuel is allways the last. If everything is correct then you look at the boat trim, water in the doublebottom, dirty hull/prop and prop pitch
 
That was to be 100 to 106 comperssion on cylinders. Typeo.
Can anyonetell me about the exhaust holes if water should be coming out while ideling at 1000 rpms. It would chug then water comes out then black smoke. Is this normal.
 
I tested fuel for water. No water in fuel. I did spark test at 7/16 gap and all were the same nice long blue arc across gap. But the arc did seem to be a little thin.in the sun light. I did TDC for each cylinder and did timming light on each one at 1000rpms and #1 showed 4deg after TDC and looked to be the same for all cylinders. Did not get a chance to do stator volts test.
 
Update. I tested the stator and tests show low volts on one of the brown wires and orange wires show low too. So I did want to spend money but I ordered a new STATOR. I did a spark test at 7/16 gap and spark very light and thin arc on all cylinders so I tested the stator. Make sence that not all fuel is being burned at top end there for low rpms. I hope this works. If not at least I wont have to think its the stator or power pack or plugs. Stator isto be here on Friday. Hope to have it instaled and test run on Saturday. Will update after test run.
 
It is recommended you replace the regulator/rectifier with a new stator but not absolutely necessary. What kind of battery are you using? The old style lead acid battery is the best for the charging system. Do you have a volt meter on the dash if not is a good upgrade. Over voltage at high rpms is the most common cause of stator failure wether it is a bad battery or rectifier. Real time monitoring can prevent costly repairs in the future. Hope the stator cures the ailment.
 
I put new stator on today and checked to compair. Old stator on brown wires showed 124-126 on one side and 129-130 on the other brown wires and 50 on orange wires. New stator showes 138-139 brown wires and 138-140 other brown wires and 80 on orange wire. This should increace my spark and alow pulgs to burn all fuel. I started it on water muffs and I have noticed a big change while idel. Seams much smother and not as much smoke from exahust. Will be able to test run monday morning. Hope this was my answer to no top end.
 
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