Mariner dies when shifing into gear.

Even local tech at a loss! My 1989 Mariner 115 hp, 4 cyl., 2 cycle doesn't like the water!
Started working on it 2 months ago. I replaced oil reservoir and the warning module. Replaced poppet valve and thermostat.
Compression: 120 all four cylinders. New battery. Spark only on #4. Replaced four spark plugs. Replaced rectifier. Stator tested ok on low speed, just a few volts off on high speed windings. Replaced one weak coil. Replaced pack, spark on all four. Cleaned all four carbs using 80# air. Inspected reed valves without disassembling. Inspected cylinders, all smooth, no scratches or burns. Rebuilt fuel pump. Replaced both fuel filters and fuel/water seperator. Replaced soft gas tubing clamps. Replaced primer ball. Installed new water pump kit. Had added oil to gas in tank, not sure if oil pump worked. Drained fuel tank, added sea foam and new gas. Timed carbs and timming per oem manual. adjusted carbs on water hose and it ran great. Took boat to lake and started it in water. Engine starts, sounds great from 750rpm up to 5000, but stops dead when popped into gear. Could only keep it running in gear using enrichment valve to rev engine then pop it in.

If I punched the enrichment valve, it would smooth out and rev up some, then go fall back. This is essentially the same problem I began having last summer before the pack failed. I believe it to be a problem in the fuel system, but can't identify it. The only things I didn't do, or check, on the fuel system is the two check valves at the crank case fed by the enrichment valve, which obviously work because the enrichment valve does feed them. I didn't clean the pulse hole behind the fuel pump when I rebuilt the pump, but the pump is obviously working. Even removed lower unit to make sure nothing had jamed. When I pop it into either gear, it's like someone jams a wedge into the gears. It stops that quick. This is my first post, so someone please help me out here. What else can I do? "The Mongose is Sea SICK!!"

Re: Mariner dies when shifing into gear.

Often after rebuilding carbs at home, novice outboard mechanics adjust the idle mixture to 'Best' idle speed while running the motor on the hose. This is way too lean as once the boat is in the water and has back-pressure on the exhaust, the motor demands more idle mixture fuel to run at 'Best' idle speed. Then again, two stoke motors do not have accelerator pumps, so yet again, the idle mixture must be even richer than this 'Best' idle while in the water, and IN gear.

Turn the idle mixture screws IN to very L I G H T L Y seated, then back each out 1 and 1/2 turns. This should provide enough fuel to get the motor started and IN Forward gear once launched. Now very SLOWLY adjust each mixture to 'Best' idle speed while IN gear and IN the water. If idle speed gets too high or low, you may have to adjust the idle speed setting.

Once set to this loaded idle on the water you still need additional fuel for crisp acceleration. Further open each idle mixture screw just the width of the screw driver slot. Test acceleration/holeshot. ANY bog, lean miss, or hesitation indicates a need for more idle fuel.

Again adjust the idle mixture screws just the width of the blade slot. Retest acceleration. Repeat adjustment and testing until perfection.

Note; a heavier laden boat may require even more idle mixture to accelerate then the same boat lightly loaded. A couple of loaded coolers, or pulling a tube may require another slight adjustment to the idle mixture.

Also, your motor is special, is does have an accelerator pump that gives a shot of fuel to the lower two cyls as the throttle is opening to assist them to begin firing and make power. Ensure the accelerator injector nozzles are clean and functioning, spraying the fuel correctly when the pump stokes is made.

Re: Mariner dies when shifing into gear.

Thanks for the come-back. The idle jets were adjusted to 1 1/2 turns each on #1 and #2. Only other adjustment on the hose was a 1/4 turn richer. In the water, I tried opening each #1 and #2 idle jet up to 2 more turns, and it still killed the engine.

I didn't get to do the "loaded" adjustment because it stalled when put in gear. This step is very interesting. I knew there was more load on the engine in the water, but failed to realize how much. I will try to get the boat wet in the morning, and, using the enrichment valve, get it running in gear to do the adjustment you priovide. (this time I will hang the screwdriver on wire to prevent the fifth one from sticking in the lake bottom with the other four).

Been doing a little of this since the late 50's, but never heard, or considered the acceleration/holeshot adjustment!...cool.

What is the best way to clean the injector nozzles? remove? or spray under pressure?

Re: Mariner dies when shifing into gear.

Remove injector nozzles from motor, reconnect fuel hoses.

I like Wally World Super Tech Carb Cleaner, cheap yet one of the best solvents I've found, fill the fuel hoses and the injector pump and repeatedly stroke the pump to squirt chemical thru the system and injector while watching for a good conical spray pattern.

The injectors have a check valve to eliminate weepage and won't begin to spray until there is 3 - 4 psi then 'pops' open releasing a fine spray.

Re: Mariner dies when shifing into gear.

Thanks Admiral. Just finished cleaning the injectors, and they are pristene. check works with mouth pressure and vacume. No discussing stuff on pipe cleaner through hole. Also cleaned the pulse holes for the fuel pump, which were ok anyway.

I like your idea about filling the tubing. I'll try to get some from Wallie World this evening and fill all the tubing with it after removing the gas/oil. Then purge the system before sending in the gas.

I cant get the boat wet in the lake this afternoon because it's cover is getting VERY wet from above right now. Will try tomorrow, and let you know......

Crapies are tearing it up, Stripers hitting big time, Cats are everywhere, and Bass are on the bed in the flats........I'm stuck on shore!!!!!!!! Mongose

Re: Mariner dies when shifing into gear.

Well Admiral, I got the boat out yesterday afternoon and in the lake. Same problem. Even after using your sugestion, with the idle jets out a full 4 turns, same thing. Same thing after trying to increase idle rpms with the idle timing adjustment. I could only get it in gear by punching the "choke", then as the motor reved up, pop it into gear and increasing the throttle slightly. I say slightly, because if I went far enough to crack the bottom two carbs, it would bog down and stall. The last time I did this I was running the boat up to the trailer, and I heard the reed valves start to "slap". I quickly turned it off and hand loaded it. That proves to me it is still starving for fuel and lube.

Next step is to try the clear tube to see if there is air getting in now that wasn't last week. Then, every tube, port, and check valve will come out and be washed with carb cleaner and blow dry, and check for any leaks I couldn't find before. While I'm at it, I think I will bypass the water/fuel seperator to see if the China made thingy inside is restrictive. I think I have covered most of this before, but not all a the same time. What do you think?

If you have any other ideas, I shur would like to hear them......thanks again......sad mongose

Re: Mariner dies when shifing into gear.

When you 'bump' the key in hitting the enrichener (choke) and performance picks up that is pretty much proof that you still have a fueling problem.

Still, just to drill, you should verify spark and compression to rule out all other possibiliities. It doesn't take long and prevents you from chasing phantom problems. Remember, when testing spark always disconnect the throttle cable and to slowly move the throttle (and timing) WOT and back, this moves the trigger wiring, if one is broken you would see a failure in spark on that cyl as the wires are moved.

Now, once done verifying spark and compression, get back to the carbs.

Do you have a copy of the FACTORY service manual, it is/will become your BIBLE. Check these links

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

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

WOT timing then carb link and synch is critical as well as the accelerator fuel pump shot and cam adjustment so to begin firing the lower two cyls as the carbs begin opening.

There is an air gap in the fuel pump that is taken up as the throttle is advanced. Note that as the throttle is advanced it advances the timing a bit before actually opening the carbs, this accel pump gap should be near identical so that the pump squirts the injectors at precisely the same moment that the carbs begin to open.

Once everything is dialed in exactly as spelled out in the factory manual the transition from two to four cyls is near seamless.

Re: Mariner dies when shifing into gear.

Cleaned all four carbs using 80# air.

Click to expand...

Did you rebuild the carbs or just blow them out with high pressure air??

Re: Mariner dies when shifing into gear.

On the carbs: I removed them all, dissembled (except the high speed) inspected all parts with a 3 power jewelers loupe and found no problems with the parts. Replaced gaskets and checked adj. of float.

I plan to get back on the motor this afternoon and follow through with your suggestions, and check that the timing and pump are very close to each other....hadn't done that before.

I have the OEM factory manual, and followed it in setup, but there is one place that is not very accurate...that being when you alighn the cam mark with the "center" of the roller. That can be off in eather way, and could be a perspective problem.

I now see why the measurement between the acc. pump and the cam is so important. Has to be close because of it having to open the pump with the timming advance.

thanks again.....I'll let you know........Hopeful Mongose

Re: Mariner dies when shifing into gear.

Ok, I removed the tubing to the accelerater pump and injectors under cylenders 3 and 4. cleaned and inspected again, and checked the restrictor in the return side of the hose and it was clear. Took the accelerater pump apart and will order a new one, because the diaphram looks like it may be "dry rotted" with small cracks. It hasn't started leaking however because no gas has started comming out the bleed hole in back, so I'll keep using it until I can get a new one. Started the motor on hose, took the fuel intake hose off the fuel/water seperator and stuck it into a glass jar filled with Wallie World carb cleaner and sucked it into the carbs and all the fuel hoses on the engine. When it started smoking, shut down the engine and checked to make sure all the tubing and carb bowls in the engine had cleaner in it. Waited 10 minutes then hooked up the intake hose back to the fuel/water seperater and cranked the engine. I ran the engine until the smoke cleared, and it sounded ready to go. Took it to the lake and started it in the water. It would start right up, and hold idle at about 900 rpm in neutral. Pop it into forward and it died. The only difference now, instead of stopping suddenly, it will at least fire a few times as it dies, then smokes a lot when I re-crank it.

I took it to a suggested mech that has a rep of knowing about Mercury. Gave him a list of what I had done and the results. Since his place is limited on space, he said he would call when he got room for my boat inside, because it's too nice to sit in the weather. He called two days later and said according to my list, there was nothing more he could do than what I had already done, so there was no point to paying him to re-do everything. I respect that!!!

I found another thread you took part in back in early 2011 with a guy that thought the 2 + 2 was such a bad idea, even Mercury wouldn't explain it in their manual. I don't know what manual he has, because mine does explain it. You gave a really good description about how to time the carbs and the results. I have printed it and other information I glean from forums and am forming a book!

Back to the engine.....I have a very distinct picture (in my mind) showing the position of the cam lever and follower, and the timming screws (idle, max, and low speed), and the adjustments I have now, using the manual, are far removed from what they were. I understand that there could be subtal differences, but I don't think they should end up that far off. For instance, the alignment of the mark on the cam is now in the center of the roller of the cam follower. Before, at idle, the mark was higher than the outside edge of the roller, and the roller was right at the corner of the half hole in the lever. The excellerater pump plunger was off the back of the cam about 1/16 inch, and now is pressed tight to it, which makes it open the instant the throttle opens. The idle adjustment screw on the throttle arm was about half way out, and now is only 1/4 of an inch from all the way in. The same for the low speed timming screw.

Putting all this information together in my mind and visualizing it as a mental "movie" of what is happening, I am now thinking I might be going the wrong direction trying to increase fuel flow the the engine. I might, in fact be flowing more fuel to the engine than it can use until advancing timming takes over...........yesss, closely watching all the actions on that side of the engine, the carbs are opening before timming advance occurs, and with the added spray into the cylenders by the injecters may be more than the engine can use at idle rpm.

My next approach will be to back out all the timming screws so they wont influence the carb linkage and cam adjustment, THEN adjust the max open carb shutter stop screw, then the cam follower, to see if the result is closer to what it was in the beginning, then go from there with the ignition timming.

If you have any other suggestions, please let me know.........Mongose

Re: Mariner dies when shifing into gear.

You're on the right track.

There should be an air gap between the carb linkage roller and the actual throttles, this give space for the timing to advance before the carbs actually open.

There is also a smaller gap between the accel pump and cam, here again this space is closed so that the accel pump begins to pump 'just' as the carbs open.

Back off all linkage adjustments, sync the actual carb linkage, then follow the directions spelled out exactly in the order prescribed by the manual.

Re: Mariner dies when shifing into gear.

Ok! I'm going to get this done Sunday afternoon if it doesn't rain again. If everything goes as planned, I'll have it ready to water test on monday. As always, thanks for your input. Sure feels good having someone around that knows about the subject..........Mongose

Re: Mariner dies when shifing into gear.

Got it all done, and guess what? The cam setting looks the way it did when i first started this whole thing. The manual doesn't give any info on what the timming should be when you first start sinc-ing the carbs. By backing off the high speed timming, the idle timing and the idle set screw it gets these out of the way to do the carbs right. Cranked it on hose and started with the first push of the "choke", and idled at 750 rpm. You can hear two cylanders firing strong with only an occasional miss. As the throttle are is advanced slowly, the engine smothes out with no miss and continues to climb until the plunger on the accelerater pump is touched, then all hell breaks loose, and the rpms shoots rapidly up to 4500 to 5000 rpm and it wakes up the neighborhood!!! No skip, no miss, no faltering, just screams like a banchee.

Didn't have time to take it to the lake for the water test and ajustments. Today the wind is howling at 35 mph and is 40 deg., so I think I will to accounting this morning and take it later if wind lays, or tomorrow if it doesn't. I'll let you know.....keep your fingers. crossed.........Mongose

Re: Mariner dies when shifing into gear.

You notice how idles speed is adjusted with idle timing, which has no effect or change on WOT timing.

Initial throttle cable movement first starts increasing timing which increases idle speed up to the point the carb linkage roller makes contact, from there the carbs open and timing keeps increasing until you get to maximum timing, from there on it is only carbs continuing to open.

Re: Mariner dies when shifing into gear.

Well, CharlieB, had the boat in the lake (still on trailer), and still the same old story. Spent an hour tweeking. Went all the way out to four turns on the idle jets a quarter of turn on each between atempts to start. Only a slight change in sound of idle, re-set idle at 1 1/2. Tried idle screw adjusting and got idle to 900 and no help, only a bad clunk in gear shift. Reset idle to 700. Checked clearance of less than .020 between idler roller and cam. Plunger of accelerator pump off back of cam about 1/16 inch, and wide open cam is within .030 of pump housing. I did get it to run in forward gear once, but when I tried to slowly open the throttle, it bogged down and almost died. I eased the throttle open a few more times and finaly it started increasing rpm's. It increased stedily as I opened the throttle up to about 2000 rpm, then without moving the throttle any more, it suddenly screamed up to 5000 before I could get off it. I'm glad I hook the winch strap under the bow roller, because the boat would have gone through the back window of my explorer! TVA will probably want to know who washed out the end of their boat ramp!!! After all this, I could start it right up, but it wouldn't run in gear.

You know, I've cleaned all four carbs 3 times, but as yet, I haven't removed the high speed jets in #3 and 4. They are glued in with something red. Would you advise going there if I mark each to return them to where they are now? or not? What will take off the red "glue"?

Next step is to change out the spark plugs....again, and read the DVA specs for the stator and trigger, and if they are ok, I might just feed it a very large red fire cracker! It wouldn't take much more of this to make me put a remanufactored long block on there, but it would be my luck that something in the carbs, etc are still the problem, and I would just end up with a more expensive problem the same as now!

I've gone to two tech (heh! mechanics (?)) here, and they couldn't help. Know of any real merc techs near Atlanta? That would be well worth the 2 hour drive!.............Mongose

Re: Mariner dies when shifing into gear.

You know, I've cleaned all four carbs 3 times, but as yet, I haven't removed the high speed jets in #3 and 4. They are glued in with something red.

Click to expand...

Those are not high speed jets and leave em alone....... Get yourself a plastic barrel and cut it so you can run this engine with back pressure on it and redo your sync and link.

now of any real merc techs near Atlanta? That would be well worth the 2 hour drive!

Click to expand...

You near choo-choo?

Re: Mariner dies when shifing into gear.

About 1 1/2 - 2 hrs depending on traffic on mtn river rd.

Know someone there that might help?.......mongose

Re: Mariner dies when shifing into gear.

Thanks again...........I didn't think about the plastic drum I bought last year for a gutter drain!!! I will cut the top off today and start from scratch with the motor in it. I'll save the $20 in gas and more in time doing it this way. @=z*& wow! Thanks for giggling my brain........mongose

Re: Mariner dies when shifing into gear.

Ok guys. Thanks for all the help. Been very busy in my shop last three weeks and couldn't work on the boat. Yesterday, checked all the adjustments and they were right. Couldn't find any way that the shift/throttle lever would advance the spark when put into gear, so went back to my "Mariner Bible" and just started reading. Way in the back of the book, is instructions on how to set up the gear shift and throttle on a new installation. I figured no reason not to try, so I started from O and set up the two connections as per the book. Got the advance you talked about, so I filled my drum w/the motor in it, cranked it, warmed it up a couple of minutes then popped it into gear......didn't even slow down! Tried reverse, neutral, forward several times and it ran smooth as ever. Took it to the lake with my grandson this morning to try it out. Two people, 350 pounds, two 115 amp batteries, 18 gallons of gas, tournament load of fishing tackle, storage lockers full, front locker full of life preservers, and who knows what else, gave me 55 mph! Just 2 mph less than it would 23 years ago when it was new!
This adjustment might be something to remember when helping others with my problem. If the shift lever is not set up correctly to the shifting slide on the motor, the remote controll wont produce the spark advance necessary to keep the motor going with the back pressure of the water. Thanks again for all your help, and hope to see ya on the water>>>>>>>>>>>>>>> Mongose.