'60 Merc 300 Awakening - No SPARK

Hi,

I have begun trying to wake up a 60 Merc 300 and have worked my way thru getting the electric start working well with various issues from wiring to a starter that did not retract etc. Luckily with some great help in this forum I have avoided buying any parts(came really close to getting a $75 starter solenoid but found out it was just hot wire connection issue).

Now for the newest stumper......No Spark at all. I removed the magnito and cleaned the points, set the gap at .20 and fixed a nearly severed ground line to block etc. and crossed my fingers
and turned it over but still nothing.

One thing I noticed the second I took the cowl off is a bunch of melted brown tar running down the head and my first thought was the stator( I saw that same thing on another motor I had one time...85 Evinrude) Some knowledgeable with a barn full of old Mercs and boats told me that sometimes they overdue it on the sealant on the block or something but I am thinking it is stator or something melting. I didn't get to pull the flywheel yet as I ran out of daylight and I need to get the right sized socket(what size is it btw...1"?) and 3 bolts to fit into my puller(what size are those fine threaded ones ?).

Any hints and tips would be greatly appreciated. I was pretty excited about diagnosing and getting the electric start to begin working correctly only to be brought back
to reality when I still have no spark. As for the plugs...they are the correct Champion 6J6's(clean and not burnt or anything btw) and when I went to the local marine place today they had nothing in stock(looked up motor/yr and said they referenced B6S...and didn't have).
In any case I find it hard that all 4 would be bad and not even cough if one or two were still working.

Thanks for any thoughts on how to continue.

SIncerely,
Tim

Re: '60 Merc 300 Awakening - No SPARK

Don't pull the flywheel, atleast not untill you ohm test the stator.
It pretty simple, test for reistance on the two yellow wires from the stator. if there is a low resistance, (under infinity) then test to see if there is continuity between either of the stator wires, and the block (ground).
If there IS continuity to ground, anything less than infinity, then the stator is no good. I run J6C's in my 800. Should be ok in yours too. As for no spark
test your ignition switch, I had no spark, turned out the switch was NFG.
Next test your wiring harness, for old merc syndrom. Basicly the wires get old, corroded, and either short, or open. Hope it helps.

Re: '60 Merc 300 Awakening - No SPARK

Hi,

Set you points at .09 to .10 thou. (unless you have a dwell plate to set them up on) If you sanded them polish the with 1200 or 2000 grit wet or dry sandpaper and wipe them with white paper to make sure there is no grit left on the contacts. I do this when the point contacts are closed by dragging it between the contacts. Double check the condenser and ground out wire to make sure they are not touching the point base plate causing a direct short to ground.
If you coil cover is soft replace it. Also look the bottom of it to
make sure it is not shorting out to the dist body.
Remove the 4 little screws that hold you plug wires into the dist cap.
Take a side cutters and cut the plug wire where the screw indentation is and put them back in the cap being careful to get them all the way in and put the set screws back into the cap. You may have to pull a little wire back towards the dist cap do to shortening the wires.
Clean the cap if it has carbon tracks in it.
Make sure you do not break the center carbon when putting it back together.
Leave the wires off the dist stud when you try it out for spark. It is a magneto and the wire may be grounding it out. That is all it is for, to ground out the spark. If you have two wires on the stud one is for a mercury switch the grounds out the dist if you hit something in the water and the engine flips up.
Champion J6J's are fine for your motor, use them.
Don't worry about your stator they never went bad.
Don't worry about the brown sealant. That is normal. If you see a clean area then you have a crankcase leak.

Re: '60 Merc 300 Awakening - No SPARK

Wow thanks for the quick responses. First to Fuzzyboy and then I will go back and read the second.

I will test the yellow wires on the stator as you suggested and YES I am encouraged about your ignition switch idea. The switch was nearly totally froze up after all the years in that barn and it took me a while just to get it to be able to turn the key(it still will not come out and won't drop back from start to on). I have an extra set(harness with key and choke) a friend lent me so I will try that again. It took me forever to get the original harness to even first engage the choke and then to drive enough power to the solenoid.

Thanks and I will keep you posted......might even go out and fire up the spot lights now

Tim

Re: '60 Merc 300 Awakening - No SPARK

Corm,

Thanks for taking the time to respond.

You said"
Hi,

Set you points at .09 to .10 thou. (unless you have a dwell plate to set them up on) If you sanded them polish the with 1200 or 2000 grit wet or dry sandpaper and wipe them with white paper to make sure there is no grit left on the contacts. I do this when the point contacts are closed by dragging it between the contacts. Double check the condenser and ground out wire to make sure they are not touching the point base plate causing a direct short to ground.
If you coil cover is soft replace it. Also look the bottom of it to
make sure it is not shorting out to the dist body.
Remove the 4 little screws that hold you plug wires into the dist cap.
Take a side cutters and cut the plug wire where the screw indentation is and put them back in the cap being careful to get them all the way in and put the set screws back into the cap. You may have to pull a little wire back towards the dist cap do to shortening the wires.
Clean the cap if it has carbon tracks in it.
Make sure you do not break the center carbon when putting it back together.
Leave the wires off the dist stud when you try it out for spark. It is a magneto and the wire may be grounding it out. That is all it is for, to ground out the spark. If you have two wires on the stud one is for a mercury switch the grounds out the dist if you hit something in the water and the engine flips up.
Champion J6J's are fine for your motor, use them.
Don't worry about your stator they never went bad.
Don't worry about the brown sealant. That is normal. If you see a clean area then you have a crankcase leak.
__________________
Have Fun,

As far as setting the points to .09 to .10 thou....the copy of the service manual I have says to "Set the breaker point gap to .008"(0.203mm) for an approximate setting of 48degree dwell. Then I found this online entitled Troubleshooting Outboard engines with Magnito Ignitions:
Before leaving the points,
make a visual inspection of the gap
in the open position. A typical
specification would be 0.020 inches.
That is what I set it to ...I have an old set of plug gap tool that I assume is in mm's and set it to 0.020.
Suggestions?

I didn't have any wet sandpaper that fine so I just carefully scrapped the points with a carpet knife(making sure not to go thru to metal) and cleaned with solvent.

I didn't test the condensor and will when I pull it again.

As for the coil cover...I assume you meant that waxy brown thing beside the points and condensor? Yes it was soft...again like wax...with the "breaker arm" coming out of it? (sorry but I have only had experience with OMC engines with coils that look way differernt. What is with the plastic screw.....does this adjust the tension on the breaker arm or something? How should it be adjusted?


All the stuff about the plug wires and cutting them off..I need to digest it a bit to understand. As for the confirmation that the brown stuff is only sealant(what a messy job if so) and that the stator is probably good.

I will get back at it when the sun comes up and thanks again to you both for your assistance.

I may even have this thing running in time for vacation in two weeks with your kind help.

Tim

Re: '60 Merc 300 Awakening - No SPARK

Hi,

As far as setting the points to .09 to .10 thou....the copy of the service manual I have says to "Set the breaker point gap to .008"(0.203mm) for an approximate setting of 48degree dwell. Then I found this online entitled Troubleshooting Outboard engines with Magnito Ignitions:

Click to expand...

That is correct. For most people a tight .09 or .010 is a good .08. The older engines with worn cam lobes ran better at .010

Before leaving the points,
make a visual inspection of the gap
in the open position. A typical
specification would be 0.020 inches.
That is what I set it to ...I have an old set of plug gap tool that I assume is in mm's and set it to 0.020.
Suggestions?

Click to expand...

Buy a feeler gauge in thousands somewhere they are cheap.
Any auto store or big box store should have one.

I didn't have any wet sandpaper that fine so I just carefully scrapped the points with a carpet knife(making sure not to go thru to metal) and cleaned with solvent.

Click to expand...

You want to polish the contact so you do not create any pitting from the rough surface. If you managed to keep the surface smooth your good to go.

I didn't test the condensor and will when I pull it again.

Click to expand...

These Merc condensors rarely went bad. Just make sure the wire end is not grounding out on the base plate. If you have a way to check by all means do so.

As for the coil cover...I assume you meant that waxy brown thing beside the points and condensor? Yes it was soft...again like wax...with the "breaker arm" coming out of it? (sorry but I have only had experience with OMC engines with coils that look way differernt. What is with the plastic screw.....does this adjust the tension on the breaker arm or something? How should it be adjusted?

Click to expand...

When the coil cover gets soft it allows current to leak out of it reducing the coil output or just plain shorting to ground. When we would run them on a Merc-O-Tronic they would actually glow blue from the leakage. If you take it out look for any holes burnt through the covering. That is where it will be arcing to ground. The Plastic screw nut just holds the arm in place so it contacts the post on the dist cap to allow the spark to flow to the rotor, then to the dist cap posts which are connected to you plug wires through the screws.

All the stuff about the plug wires and cutting them off..I need to digest it a bit to understand.

Click to expand...

On a lot of old Mercs with a lot of run hrs on them the plugwire burns away inside the casing where the screw point runs into it. Causing the spark to have to jump to get to the wire. The less jumps it has to make the better off you will be in the long run.

As for the confirmation that the brown stuff is only sealant(what a messy job if so) and that the stator is probably good.

Click to expand...

I have never seen one go bad. All it does is charge your battery. All you need you battery for is the starter and lights. Unless someone ran 12 volts through it at sometime. Then it is toast. Before they had alternators I just charged up the battery every other time or everytime if I was starting and stoping it a lot.

Re: '60 Merc 300 Awakening - No SPARK

Thanks again for the detailed instructions. As I am running against the clock for a usable boat/motor for my vacation in Canada with my boys in 3 weeks I have given up on the total classic 66 Whaler restore and now working on a temporary solution of having a working fishing/playing boat and motor combo.

Today I picked up a nice old'59 Big Twin Evinrude 35 HP(borrowed from a friend) that has the biggest head imaginable on it but it is really clean and I managed to get it loaded on the boat and started up nicely but is not peeing so as I had already planned...will put a new water/pump kit into it.

As for my favorite(the 60 Merc 300) that will match up with the 66 Whaler when I get back from vacation...I will try to continue with your tips and hope to get it restored and working nicely soon(time permitting).

THanks again for taking the time to help.

Tim

Re: '60 Merc 300 Awakening - No SPARK

ya the evinrude 35 is really big from exp

about the merc ur doing good on i would check out ur wires makes sure that there ok the spark plug wires and boots and springs.

on the electric start i had problems on my 61 merc500 basically same motor. ya i had to replace the coil on mine and just replaced the condensor for the heck of it. make sure u dont lose anything in the melted coil.

if ur having electric start problems im like a expert on this heck of motor jeeze its so compact!!! hard and annoying. well yup so if u r i guess start off by jumping ur starter with cables to see if its good

Re: '60 Merc 300 Awakening - No SPARK

I will check the plug wires again...they looked fine. I am going to pick up a ignition rebuilt kit and a new coil soon and do it all at the same time. Question though....is the coil underneath that wax round thing inside the Magnito case? Very weird compared to OMC coils I'll say.

As for jumping to the starter....I got all my starting problems worked out and it is turning over nicely.....no I need spark.

Thanks,
Timmy

Re: '60 Merc 300 Awakening - No SPARK

timmeraw said:

it Question though....is the coil underneath that wax round thing inside the Magnito case?

Click to expand...

That is the coil. It is held in by the two allen screws.

Re: '60 Merc 300 Awakening - No SPARK

Ok before I start throwing parts at this spark issue(just found out the coil is like $80).....could the fact that I mistakenly set the points incorrectly to .020 instead of the proper .080-.090 as mentioned by Corm I think....could this cause absolutely no spark or just cause it to fire at improper times?

In the mean time, I am trying to locate a dealer to buy a ignition tune-up kit(points/condensor). I also have a water pump/impellar ordered and it should arrive today so I will then attempt to replace it in the Merc 300....though it certainly sounds to be much more complicated than any I have replaced in OMC's. Actually just found a good explanation by Corm way back in 2000 to a guy working on a mark 25...which I assume is similar. (btw i am also trying to get my hands on a repair manual(have some copies of various chapters) ....got outbid at last second on a good deal on e-bay on the weekend so it is back to the search.
Thanks

Re: '60 Merc 300 Awakening - No SPARK

Hi,

I would re set the points and try it before tossing any real money at it.
You can spin the dist shaft, with the cap installed, by hand and the plugs grounded to see if you get spark. The coil, even in poor condition should give you a little spark. Don't touch the little stud on the side of the dist while doing this. Leave the wires off it too. The Merc points have a lot of tungsten on them and don't need replacing unless they are pitted up.

Re: '60 Merc 300 Awakening - No SPARK

YESSSSS!!! The old 300 is awake and purring like a kitten. I cleaned and reset the points properly(~.08-.09) and cleaned all the contacts in the distributor cap....thru it back together and boom she fired but quickly died. I was extatic. So I made sure the gas tank had more fuel...the ball was hard....removed 3 of the 4 plugs(I what a pain that bottom one is) cleaned the contacts and replaced. Then she fired right up and roared like a lion(had thottle set to high by hand) ...but she was running. Unfotunately in running so hard it expelled too much water out of the can so I shut it off and lugged more water to it. Fired it up....turned down idle and she ran along nicely while I intently watched the tell-tale for proper impellar/thermo function and sure enough after about a minute she was peeing like a 4 year old at the church picnic on the flowerbed. I did get a new waterpump kit which I will install some time soon but for now there are other priorities like:

Now I have to scramble to get the wooden console built to install the steering and controls so I can give it a real test on the water.

Thanks so much for everyones help ....this place is priceless and only made possible by the kind volunteer efforts of those that take the time to respond and help out others.

Have a great day.

Tim

0h yea...gotta ask a couple more questions. When I first checked the lower unit gear lube it was thick as mollasis(and looked like it) so I let as much drain out as possible and then filling with 90 weight oil forced it back up thru until it went from black to pretty much new stuff. Question...I am going to change again but I though I saw somewhere that these old lower units used a different oil than the new 90 weight. Is that true and what should I be getting? Also...fuel mixture....I have seen various opinions but I figure somewhere between 24-32:1 will work for both this and my 54 Johnson 25hp. Is that correct?

Update....I just got home and before I went into the house thought I give it a shot to listen to it run....boooo...turning over again but no fire. Well I only tried it for a second but now I am concerned...check it tomorrow

Re: '60 Merc 300 Awakening - No SPARK

Hi,

The Merc has all needle and ball bearings so 50-1 is fine for a mix.
It will work with the Evey mix you have to. I may be a good idea to run that mix the first tank anyway.
They ran 105 Merc Special in the gearcase but 90 is ok. I use to mix the two even though they do not mix that well like you would think.

Re: '60 Merc 300 Awakening - No SPARK

I tried again this morning for a few minutes to start the motor and it is not even trying again. Very discouraging after having it running for a while yesterday really well. Any thoughts on why after running it seems dead again( I didn;t have any time to really get into it). I did stop by a Napa store I was going by today and asked for some J6J plugs but they didn't have any. The guy talked me into some J6C plugs and now when I get home I looked at my notes and see that the alternative champion is J6M. Will the J6C's be ok?

I will get back at it tomorrow but any hints would be gratefully appreciated.

Thanks,
Tim

Re: '60 Merc 300 Awakening - No SPARK

Hi,

J6C is the same plug. Just a different electrode material.
If you points did not close up and your condenser wire is not grounded
then your coil may have given up. If you have no spark that is. If you have spark then it is a fuel problem.

Re: '60 Merc 300 Awakening - No SPARK

Ok...she's back awake. I put in the new plugs....gave em each a squirt of mixed fuel, engaged the choke and she is running again. One thing I noticed......I don't have the shifter cables hooked up and it jumped into forward when i was adjusting the idle turning the magnito. I put it back into neutral and manually attempted to test reverse slowly engaging with the arm. It began to grind so I stopped. I need to change the gear lube again after only one replacement of the "molassis" that was in there before I attempt running in any gear beyond neutral. Would it normally grind a bit going into reverse if not doing so quickly with controls?

Thanks.
Tim

Re: '60 Merc 300 Awakening - No SPARK

Hi,

You have to shift them quick or they will grind.
Shifting by hand into reverse is a little hard because you have to engage the reverse lock system while shifting. The control box gives you added leverage
to do it smoothly. I would not be to concerned with the gear lube for a few runs.

Re: '60 Merc 300 Awakening - No SPARK

On to the next job....replacing the impellar. I purchased a water pump repair kit and even though it is pumping water... one should always replace an impellar on any
new-2-you used outboard.

I have been doing some research here and in other places and it does not look nearly as easy as it is on an OMC motor(which I have done many times). It appears that to start I need to take it apart up near the head and not just above the lower unit as normal with OMC engines. Then apparently I may need a special tool to remove the water pump housing.

Any instructions and tips are greatly appreciated. I am still trying to get a manual having missed one on e-bay and do have some copied pages from one but it does not go into detail on how to start.

Thanks as usual...this place is the best.

Re: '60 Merc 300 Awakening - No SPARK

ok this is one the hard parts of the motor. ok take lower unit off should be four bolts. where driveshaft comes out of lower unit. there a cover with four holes in them. if u cant get a spanner wrench then use a hammer a punch a adeuate size. spray with a wd-40 or any other item and let sit for a while then righty tighty lefty loosy the cover off. try to punch flush with the cover so ur hammer uses its full potential to move it. use hard punches the less the better. then take wearplate off and such 2 screwdrivers to take impeller out if stuck in there pretty good may neeed a dremel to take out