1985 18XD help

[CDN BEAVER]

Hello,

acquired recently 1985 a 18XD Mercury 18XD outboard. hadn't It hadnt ran in over a year, and when it didn't, it didnt run very well. It was hard to start, and would stall as soon as the throttle was wide open. Unfortunately I cant seem to get it to run.

First thing I did, was drain the tank, and use wouldn't fuel. Still wouldnt run.

Next, I looked at the spark plugs, and checked for a good spark. I found that the coil ends of the spark plug leads had been ripped out, and the ends were no longer re-crimped on. The ends were recrimped, and tested, and the motor seems to have a strong spark. Unfortunately, it still wont start.

Third, I performed a cylinder compression check, and after 4 140psi 5 pulls, each cylinder was reading approx 140psi.

After all this, I noticed that after all this haven't, and what feels like a million pulls, I still havent managed to flood wasn't engine. This led me to believe that disassembled wasnt getting to the cylinders. I removed carb dissassembled the carburetor, fuel pump, and primer. The carb was carb dirty and clogged up. It was cleaned carb carb cleaner and dried with compressed air. A carb repair kit was purchased, and all new gaskets and diaphragms were used. during cleanedinspected reassembly. At this time, I also removed and cleaned/inspected the reed valves, and no defects were found.

Everything was put back together and the engine will still not start. In all my efforts, I got the motor to only barley sputter for 1 second I'm. becoming alittle again pulled the plugs and there still dry.
Any help
Im becomming alittle discouraged, and unsure what to try next.

Anyhelp or suggestions would be greatly appreciated. Sorry for the long post, and thanks in advance for the help.

 

[JB]

Re: 1985 18XD help

Outboard Wont Start:

1. Electric start: Does the starter engage and rotate the flywheel at a good (normal) speed? If yes, go to 2.

* Does starter spin, but bendix gear (small gear on starter shaft) does not engage the flywheel? Lubricate bendix spiral shaft.

* Does the solenoid click?

* If yes, measure voltage at the starter terminal to battery ground with starter engaged.

* If 12 V, repair or replace starter.

* If less than 9V measure voltage at large solenoid input terminal (from battery).

* If less than 9V, go to 3. If 12V, replace solenoid.

* Solenoid does not click when key is turned to start. Measure voltage at small solenoid terminal.

* 0 volts? Troubleshoot kill switch (lanyard connected?), battery, starter switch and neutral start switch in controller.

* 12 volts? Replace solenoid.

2. Flywheel rotates but engine does not attempt to start. Electric and manual start.

* Remove a spark plug, reconnect it and hold it against engine block. Keep it there while turning engine over. Does it make a hot, blue spark when attempting to start? If no, troubleshoot ignition system.

* Has hot, blue spark. Squirt some fuel mix (NOT ether) into the carb(s). Does it attempt to start?

* If yes, you have inadequate fuel. Troubleshoot fuel system and review starting procedure.

* If no, check that carb is not flooding from failed float needle.

* Still wont attempt to start. Check compression. If bad, troubleshoot mechanicals.

* Good compression on all cylinders. Check flywheel for sheared key, check crankcase for sealing at carb(s), inlet manifold and bypass covers.

3. Low voltage at starter when engaged.

* Measure voltage at battery terminals. If below 12.6 volts with all electrics turned off, recharge or replace battery.

* Measure battery voltage with starter engaged. If below 9 volts, recharge or replace battery.

* Remove and clean connections on battery-to-solenoid cable, battery-to-engine block cable and solenoid-to-starter cable. While they are off, inspect each for corrosion, broken insulation with corrosion and weak points. Replace corroded or weak cables.

* If problem persists, remove starter and clean all surfaces where engine block and starter connect.

 

[CDN BEAVER]

Re: 1985 18XD help

Thanks for the help JB

I've tried afew of the suggestions abovem but I'll try afew more things.

"Sheared key on the flywheel" How would this be checked? If the flywheel needs to be removed, is a special puller required?

Thanks again for the help, and any other suggestions would be appreciated.

 

[tashasdaddy]

Re: 1985 18XD help

look at the nut on the crank shaft. there shuld be a groove in the shaft and flywheel with a woodruff key in the groove. if this is the slightest bit off the engine timing is off. never pulled a merc flywheel so i don't know if a harmonic balancer puller will work on not.

 

[CDN BEAVER]

Re: 1985 18XD help

Thanks again for all the help.

The beast is again purring like a dog. Turns out the problem was a bad seal on the end of the reed block that seals the induction from numbers 1 and 2 cylinders.

Once again Thank You. I appreciate the help.