TOPIC: New member- '68 merc 1000 need help

I have a 1960 P-14 runabout made by highway products in Canby Oregon. It has a 68 merc 1000 on it that WAS running great. So far I've replaced a lot of the wiring, fuel lines, rebuilt fuel pumps. The boat used to start hard, but once going, if I pinned it the boat would literally jump out of the water and scream. Now it starts awesome when cold, idles smooth in and out of gear but is slow to plane. Once it struggles to WOT everything seems fine. If I shut it down, it's game over. Either I wait for 30-40 minutes, or crank and crank until it barely catches. Everything I've read points to the stator, which looks Almost brand new. It's not shorted to ground. Any ideas of what might be suspect? Should I pull the flywheel and inspect the stator? The yellow stator wires, where visible were badly cracked, so I cut them up under the flywheel where the insulation looked good and soldered in new wire. I also don't suspect vapour lock, since a lot of the time I was running without the engine cowling when I was fiddling/testing it. Would really like to get this boat back on the water since it always drew a crowd at the boat ramp and when it was in its prime was the fastest boat on the lake.

Here's some photos of the boat I took a year or 2 ago.

Sounds like mag issues. Check magneto from top to bottom, clean,re set points and wic gap, check all bearings replace if bad. Let us know what Mage you have and model #

I can't remember what year it is exactly. Maybe 69? The serial number plate came off and is floating around my shop or storage somewhere. It does have a distributer... so it shouldn't have a magneto, right? Should I look into the distributer and coil? I do have a manual but it isn't very good. I usually look online to find simplified procedures for testing

no magneto on the 6's either duel point dis or electronic dis. points have 2 black coils look like a car coil. electronic has 1 large orange coil.

Yep it's got the one large orange coil.

Jimmy,

My bad thought it was like my 650's. The 68's are much more advanced and look to be electronic.

No worries! I think its gotta be the coil or stator at this point. Leaning more toward the coil. Theres no good way to test it unless its hot and acting up is there? I don't really feel like going to the lake and rowing back to shore after 30 minutes to say "yep, the coil is bad". I see some NOS coils on eBay for $60, might just pick one up. I already have a NOS switch box that I'm saving for a rainy day. My grandpa tried hot wiring the old 1150 merc and fried the switch box. Said it was a $800 part and basically gave the motor away. Kind of ironic since i bought the brand new switch box for less than $100 and since then have been keeping my eye out for a motor with a bad switch box that is going for cheap. If I told him to check on eBay for a switch box he would have given me a funny look and asked if Ebay had something to do with a computer...

If the stator has just two yellow wires (yellow/blue stripe?) they are a.c out to the rectifier. That is just a lighting/battery charging stator. Not your issue unless your battery id dying and it didn't sound like it was.
Sounds like a coil breaking down when it's warmed up. That distributer may have a driver coil in it too.
I would if I was guessing try the ignition coil first (big orange one).
my .02 cents :<D

I agree on the coil being the culprit. The stator does have the yellow wires running to the rectifier. And I've never had a dead battery issue. From what I've read the stator has 2 sets of coils, one for charging the battery and one for power to the switchbox. It would make sense to me that the heavier gauge coils in the stator charge the battery, and the smaller coils power the switchbox. So in the case where heat damages the stator, I would think that the coils that power the switchbox would go first, and testing the yellow AC wires would not show any damage to the stator. Is that right? What I'm getting at- is there a way to test the coils that power the switchbox?

As far as my issue at hand, I'm in the market for a new ignition coil. It's on the list of parts and tools to buy. But, that list is very long so maybe in a few weeks

The ebay item id given is invalid, no result has been sentThe ebay item id given is invalid, no result has been sentAs previously posted, this stator only charges the battery. The stator has no interconnections to the ign system.

The switchbox is powered by the battery and has (2) 12V inputs, one, the red wire on the Stbd side of the switchbox, has power applied to it as soon as the battery is connected.

The other, a white terminal on the same side of the switchbox, is only powered when the ign key is in "ON" or "START".

If you don't have +12V at the white terminal on the Stbd side of the switchbox, you won't have spark. It is extremely uncommon for these big ol' CDI coils to go bad, so I'd bet you either it's an issue with the wiring, or the switchbox.

There is a test that you can do which will bypass the trigger assy in the distributor, and narrow-down the problem to coil or switchbox.

Here goes:

MERCURY BATTERY-POWERED CDI TEST FOR DISTRIBUTOR MODELS

This test is for the 332-2986 switchbox used from 1967-1978 on all the inlines.

This test assumes your coil is good (problems with CDI coils are rare).

DISCONNECT BATTERY

1. Turn off ignition;

2. Disconnect all 3 distributor wires on the Port side of the switchbox (and the “mercury switch” if present);

3. Remove the HV lead from the ign coil to the center of the dist. cap (remember it unplugs from the coil and unscrews from the cap);

4. Reconnect the HV lead to the COIL only;

5. Position the free end of the HV lead approx. 3/8" from ground (block, shrouds etc), and find a way to hold it there;

6. Jumper the brown and white terminals on the dist. side of the switchbox to each other.

RECONNECT BATTERY

7. Check that you have +12V at the red terminal (even with the ign off);

8. Turn on ignition and verify +12V at the white terminal (same side as the red terminal);

9. Ground the black terminal on the distributor side of the switchbox - this should cause a spark each time you touch ground.

If you get spark with the distributor bypassed, and it won't fire with the distributor connected, the trigger is bad and the entire distributor housing assy must be replaced.

If you get no spark using the test, the switchbox is probably bad. In that case, be sure to check for correct power on the switchbox, check all connections, and check the coil's resistance to make sure it's OK.

One thing I would do is check for spark after you run for 30 minutes or so and the motor quits. If you find there is no spark, be sure to check voltages at the switchbox. You can also do a quick "CDI Test" while it's hot.

Another thing of note is that these battery-powered CDI systems have a voltage threshold, below which they won't fire. I can't recall exactly what voltage, but typical for an electronic system would be around 9V or so.

If your rectifer/stator aren't putting out, the battery will run down and even if the starter will crank, more than likely voltage will be drug down so far that the CDI system won't spark.

You can check the charging system with a meter, you won't see much voltage output from it at idle, but when you raise it to a fast idle (no higher than 2000 rpm in Neutral), you'll see voltage go up. If it goes down, you're not getting any power from the charging system.

You can do resistance checks on your ign coil and inspect it for cracks or arc marks. The 332-2983A 5 coil is NLA but can be upgraded with the newer-style 332-4895A 5 coil.

Merc sells a kit but it's quite $$$ at around $270.

You can find serviceable used coils and switchboxes on eBay, just search for the "core" number of the coil, i.e. "2983 coil" or "4895 coil"

Here are a few search strings, the first one pulled up a new old-stock replacement coil for around $68 shipped:



New-style coil search:



Note that the later-style coil is smaller and you'd have to figure out a bracket and place to mount. But functionally identical to the older, large coil.

HTH and let us know what you find........ed

Like CW stated,...The stator on a 1000ss only has (2) yellow wires coming out of it. Those two wires both go to the rectifier with a sole purpose of charging the battery in the boat.
The power to the switchbox comes into the s-box in the red wire and when the key is on 12vdc also comes to the white terminal on the s-box.
The red & white terminals on the starboard side of the switchbox.

The big red (orange) coils rarely fail, but anything is possible.

Follow the sequence below to test the trigger (distributor).

MERCURY BATTERY-POWERED CDI TEST
FOR DISTRIBUTOR MODELS, Courtesy of Clams Canino & added clarifications by Dr. Frankenmerc

This test is for the 332-2986 switchbox used from 1967-1978 on all the inlines.

This test assumes your coil is good (most all are).

DISCONNECT BATTERY

1. Turn off ignition (temporarily for safety)
2. Disconnect all 3 wires on the distributor side of the switchbox.
3. Remove the HV (High Voltage) lead from the coil to the center cap (remember it unscrews from cap)
4. Reconnect that HV center lead to the COIL side only. (this will leave the end with the brass threaded end free to put in position as per step #5)
5. Position that HV lead about 3/8" from ground (block, shrouds etc)
and find a way to hold it there. (I gently grip the insulation of this lead about 2" away from the brass threaded end with a small pair of vise-grip pliers. The weight of the pliers can aid in positioning the brass threaded end about 3/8th inch gap from engine ground - the block)
6. Jumper the brown and white terminals on the dist. side of the switchbox together. (leave them attached to their terminals and add a 'jumper wire' that connects these two colors together)

RECONNECT BATTERY

7. Check that you have +12 V at red terminal.
8. Now,...Turn on ignition and verify +12V at white terminal that is on the red terminal side of the switchbox - (starboard side)
9. Touch the black terminal on the distributor side of the switchbox to ground (the metal case of the switchbox should be a good ground source and a metal screw-driver shank can be used to briefly make this terminal to ground contact) - This temporary contact should cause spark between the brass threaded end of the HV lead and engine ground each time you briefly make the black terminal to ground contact.

If you get a nice spark to jump about 3/8" between the brass threaded end of the HV lead and engine ground in the above test, but when everything is re-assembled and you do NOT get spark to jump at the spark plugs while they are resting against engine ground, suspect the trigger is defective as the switchbox and coil have just proven they are okay.

doc F

Very good information thank you for clearing up my confusion with the stator. And thanks for saving me the time and money I would have spent buying and installing a new coil. The wife is taking the kiddo camping tomorrow so I have a lot of time the next few days to get man stuff done. I'll do those tests you guys outlined tomorrow and report my findings. Thanks again.

Jim

That is a very good system on that engine, and quite reliable. But, being electronic it is prone to fail just from age. Capacitors in the switchbox leak, wires deteriorate, contacts corrode. Do the testing by the book and to the letter and you will find the culprit, but the coil would be the last thing I would suspect to go bad, I have never needed to replace one. Something tells me it is not ignition trouble you are experiencing however but a fuel supply problem. If you have an inboard tank check for proper venting and a restricted or leaking supply line, common on older boats, but get back to basics and check the compression as well, and don't forget to read the plugs, especially for signs of aluminum throw off which is a sign of preignition or detonation. Have you messed with timing or disturbed the belt? Leanouts can also destroy the engine as well, hit the choke when the problem occurs while running to see if it improves things. If so, start looking at fuel issues.

I'm pretty confident that it isn't a fuel or carb issue. I replaced all the fuel line with new brass fittings. New floats and needles. New gaskets on the fuel pumps. And it definately supplies enough fuel to the carbs. Could be possible that one of the quick connect fittings leak but I'm sure I checked those when did the fuel lines. When it dies on the water I can smell the fuel. I tried choke too but I think that I flood it trying to restart over and over. I can start it in the barrel let it idle for 15 minutes, come back an hour later and bump the starter and it fires right up.

Jim

And yes I also did a link and sync after cleaning carbs when it started acting up. Made it idle and start much easier, but didn't affect the problem

And I always try to run it a bit on the rich side to be safe.

OK. But check the basics first before you start replacing stuff. Ignition parts for these engines can get pretty pricey, so follow the procedures carefully. Two things to look at on the ignition side of things that give all kinds of grief are the ignition switch and the mercury tilt switch, so check that first. You can check for a bad harness or switch by disconnecting the tilt switch and running a temporary jumper wire to the switchbox red terminal from the battery 12V positive post. Make up a long jumper with an on/off switch and inline fuse, connect it and wait for the problem to occur. As soon as it does, flip on the juice and see if there is any improvement. Wiring on these old gals was never one of their strong points.

Jimmy, reading this late. I have a complete distributor,coil,switchbox from a 68 1000. Let me know if you need anything. $200 plus shipping for the whole shebang. Wiring harness included.

Jimmy55002000 wrote:

I'm pretty confident that it isn't a fuel or carb issue. I replaced all the fuel line with new brass fittings. New floats and needles. New gaskets on the fuel pumps. And it definately supplies enough fuel to the carbs. Could be possible that one of the quick connect fittings leak but I'm sure I checked those when did the fuel lines. When it dies on the water I can smell the fuel. I tried choke too but I think that I flood it trying to restart over and over. I can start it in the barrel let it idle for 15 minutes, come back an hour later and bump the starter and it fires right up.

Jim

You need to check spark right after it dies, so you can capture that event. If you find it's not sparking when hot but OK once cooled down, that's a positive clue.

Otherwise I'd bet on a fueling issue, and it may well be too much fuel not enough.

That being said, I can probably count on one hand the number of times I've actually fouled an Inline Six! In fact, every time I thought my 1350 was flooded, it needed more fuel not less!!

The culprits there are either carb issues or fuel-pump related. But we'll see!