1982 mercury 80 hp timing and idling and stalling in gear

mickyryan

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so I have a issue with this merc, I have cleaned carbs, set floats, checked needle and seats, fuel tank rebuilt fuel pump , replaced fuel lines, adjusted the carbs, compression is 125 on all 4 cylinders within 3 across all 4.
I checked to be sure pointer lines on properly with 0
can get it to start and idle but putting into gear it stalls , I have attempted to adjust timing as per instructions ,
not hi speed but the low speed, however I cant get it to go any lower then around 7 btdc (starts running like crap)even though the sticker on the cover says initial timing 4 degrees atdc.
the engine is new to me so not much known on what some one might have misadjusted before or whatever,


I took steps to adjust 1st pickup by looking at where the carb starts opening with the sliding action on the lever, then I set the throttle idle
screw just before that
then I took and set timing for 7 degrees because I had read that the first pick up and the advance at that point should be 7 degrees, engine was revving about 1500 so I backed idle off while in water to 900 it ran fine but then I had to advance timing again because it was running rough so I did it by ear when everything seemed smooth I was around 1100 rpm, I tried shifting it just stalled ... I'm at a loss and I think I am doing this wrong . the fast timing stop is set at 23 degrees as it should be.
 

mickyryan

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still cant figure out why I cant get it to even go below 5 btdc there is no way for me to get it to atdc.
 

Chris1956

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OK, Let's start small. Your motor has 4 coils and no distributor, right? Carbs open to 1-1/2 turns from lightly seated.

If so, remove the prop and spark plugs 2-4. Ground plugs in their wires to the block. Put timing light on #1 spark plug wire. Put motor in gear, and jumper starter solenoid. Now with engine cranking, advance throttle until timing light says 4-6* ATDC. Adjust throttle arm primary pickup screw, so carbs are just ready to open.
Now advance throttle to max. Crank motor and observe timing. Set max spark advance screw to 21* BTDC, and lock screw..

The next steps are done in the water, with all spark plugs and prop installed. Start and warm motor. Set idle speed to keep her running in gear. Adjust idle mixture screws for best RPM and smoothness. Now set idle stop screw so RPM is about 850-900.

Try to accelerate. Motor sill likely stall or bog. If so, open top mixture screw 1/8 turn and try to accelerate again. If she still stumbles, open bottom carb mixture screw 1/8 turn and try to accelerate. Repeat sequence again until she accelerates smoothly and idle's acceptably.

Remember, the idle stop screw and possibly the throttle cable are adjusted to change the idle speed. You may need to adjust the idle speed after the carbs are set properly. Try to keep the neutral idle RPM under 1000RPM.
 

mickyryan

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ok so i checked the timing marks once more but this time i did it with my dial and found true top of rod , the marks weren't even close so i took the top bolts loose on the flywheel and rotated it after i had true tdc , it lined right up,(appeared to be one bolt off) next i attempted to adjust for 4 degrees atdc it wouldnt even run , went and turned pickup timing till it fired and stayed running checked it was 7 degrees btdc... no clue why but it don't want to stay running under 1k 1100 it runs 1k and under it slowly dies out. max timing is fine this is the low timing and idling I'm having problems with , the carbs seem dead on i started at 1.5 turns turned in slowly till it started bogging backed out 1/4 on both carbs.
 

racerone

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Maybe there are issues with reed valves.--Or issues with crankcase compression.
 

mickyryan

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I was wondering myself about the lower seal since folks say typically this is the end result of it going is cant idle low, thing sounds great above 1k but when put it into gear it just stalls , I feel I should be able to slide into gear without giving it gas and it idle along , right?
 

Chris1956

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A leaking crankcase lower seal would cause water on the lower spark plugs to put out the fire. You will see a real clean (steam cleaned) spark plug, or even water droplets on the plug. Do you see this evidence on the spark plug?

If not, I still think you are timing her wrong, somehow.
 

mickyryan

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the bottom plug is a ton cleaner then all 3 others pullede the powerhead the seal looks like it might have been replaced its shiney and the shaft is clean but then it could be damaged so i will replace anyway since i am there,
but then heck the bolts looked like they had never been removed before and the old impeller pieces inside the water jacket there so luckily i was able to get all of those out. not sure if i go any further folks keep mentioning reeds might be bad but how would you tell , it seems to run strong at 2k rpm no stutters its just idle thats issue and going into gear , when i slip into gear with idle at 900 it stalls
 

Chris1956

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Factory reed valves rarely fail.

Since the #4 spark plug was real clean, it is very likely the lower seal is bad.

With 4 cylinders firing, maybe you can get timing specs correct.
 

mickyryan

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well i took carrier out , i lifted engine off out drive by bear hugging it , it isn't that heavy thank god :), anyways there was no rubber piece that was laying down where the shaft went through the lower unit so i am guessing i might have found my problem :) the metal piece was still intact and don't look like it had ever been replaced
the shiney thing previously mentioned was drive shaft , doh looking at things with daylight instead of flashlight gives much different perspective :)
 

racerone

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Not sure what rubber piece or shiny piece you are talking about.--But do this---Remove 3 bolts and pull the seal housing off the bottom of the engine block.-----Replace the 2 crankshaft seals and inspect bottom bearing !!!
 
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