Originally Posted by ChampioNman
1998 Ranger R93
1998 Mercury 200 EFI
"Life, liberty, and the pursuit of happiness."
All carb bowls replaced and carbs rebuilt. Motor purrs like a kitten on muffs and shows no signs of leaks. Water testing it one day this week.
Water test did not go as planned. After the carbs were rebuilt the motor ran great on muffs. I let it idle for a couple minutes and hit the throttle a few times and everything sounded good but when I put her in the lake the motor wouldn't stay running. The only way I could get it to stay running is if I gave it about a quarter throttle. Once the motor was put into gear it would die and if I let the rpms get down to idle the motor would die. My question is: if it ran great on the muffs after the carb work, what could have happened between then and when I put it in the lake to cause the motor to not run/idle? Looking for areas to troubleshoot
Muffs are only good for flushing. No exhaust back pressure is provided, that simulates being in the water. Timing should be checked, idle rpms, etc. You should also make sure your linkages are all properly set and the carbs are opening at the same time the timing arm begins to advance. They need to advance and open at the same time. If the idle adjust screws were messed with they should be reset to 5 turns out from bottom.
No idle adjust screws on a 1992 right?
Correct. My mistake coffee hasn't kicked in yet.
Make sure the mid and idle orifices haven't gotten swapped around.
In aviation we have a strict "no troubleshooting before your second cup" policy!Correct. My mistake coffee hasn't kicked in yet.
1998 Ranger R93
1998 Mercury 200 EFI
"Life, liberty, and the pursuit of happiness."
Going to pull them today and check the orifices. Will report back with findings/results.
Ok, so I took the boat over to the guys shop who did my carbs and we spent about 4 hours testing and troubleshooting. He is a retired boat mechanic and has about 50 years of experience but I we are both a little stumped. he suspected that he may have left an orifice out or put 2 in one carb by accident but we pulled all carbs and went through them carefully and they appear to be all correct. he said that everything is set as they were before. We suspect that it may be a coincidence that this problem started shortly after the carb work since it ran great on the muffs after rebuilds. Now it won't run on muffs at all unless under throttle and it doesn't sound smooth. Compression checked at 100psi on each cylinder, plugs look good. The power pack was loose. The motor will start and run for a few seconds than die unless the hot foot is being applied. One time it went into high idle for about 8 seconds and then idled rough until it slowly sputtered out. My tech seems to think the left side of the motor is getting a weak or incorrect ignition signal based on an old school spark test machine. He thinks the motor is going into limp mode. Could this be a power pack or oil injection issue? Does this sound like limp mode? Seems I'm back to the drawing board.
High idle is normal on your motor, it is QUICK start kicking in. Happens every time you start the motor and on cold start will stay in QUICK start until the motor reaches 105*F then will idle back down. Have him test the QUICK start circuit or disconnect the port side temp switch. The QUICK start wire is the white/black trace the tan wire with it is for overtemp. If bad replace the sensor, if test good replace the pack. If he has a test pack have him try that. Make sure the ground on the pack is tight.
Thanks Champion, I am taking over the troubleshooting on my own since the mechanic is an hour and a half away. We disconnected the temp switch yesterday while troubleshooting but got the same result. Ground on the pack is tight also. How do you test the QUICK start circuit? Are there any tests to confirm it is a power pack issue? It looks like packs aren't cheap so I want to rule everything out before purchasing them. The mechanic also suggested emptying out my oil reservoir and cleaning for debris or milky oil in the bottom.
Also wanted to mention that when we started looking at the power pack all 6 screws had backed out quite a bit. Not sure if this is pertinent info but thought I would include.
Download this manual it is factory and all the tests are in it. The test procedures are in the manual. https://www.selffixer.com/outboard.m....PN.508146.htm It will cost you about $15.00
Ok will do, thanks.
Just had another guy come out and check everything out. His diagnosis is that I have an air leak in my fuel line. If you watch the clear piece whee the line goes into the motor you can see air bubbles constantly. He was holding rags in front of the intakes to starve it if air and it would perk up. I am going to replace the water seperator and fuel lines and see if that fixes the issue. He was convinced that the power packs were not the issue and that at some point between when the carbs were done and I put it in the water the fuel line developed an air leak.
OK. Make sure you use BRP Hyplon hose.
will do. Should I use that line for everything from the tank to the motor?
Where is the best place to order it from?
Your local dealer should have it in stock you want 3/8" ID. I would also replace the primer bulb with a new BRP bulb also 3/8" it has yellow ends.
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