TOPIC: 1971 Merc 1350

This post is related to the '74 Marlin that I brought home last weekend. The seller found the boat documentation, but did not find the keys for the boat. He was going to spend some time looking for the keys and mail them to me once he found them. If he doesn't find the keys, then I will just put in a new switch and key.

In the interim, is there an easy way I can turn the engine over and check spark, or actually start it and check everything? To allay your fears, I am not thinking about switching careers into a life of crime, but knowing how to hotwire a boat might be handy for when I am being chased by terrorists or during the zombie apocalypse!!!

Seriously, anything I can do to check the engine without keys?

Pull the switch out. it will normally have only 3 terminals. One is the battery positive, or hot, one powers the ignition/accessories, and the other goes to the starter. Find out which one is the hot with a test light or meter, then attach a jumper to that and touch the other end to one of the other terminals. If you just see a little spark, and the motor doesn't crank, that's your ignition. If it cranks, that's you starter. So then make a semi-permanent connection to the ignition, and temporarily jump the starter to crank.
Now you know how easy it is to steal a boat

Edit: If the boat has magneto ignition, the "run" wire is shorted to ground to stop the engine, otherwise it doesn't connect to anything while running.

Guess I'll stop on the way home and pick up some small alligator clips.

So to summarize, I want to have in effect a splitter wire. One wire from the hot with a connection that stays clipped to the Run terminal when I am using it, and another wire from the hot end that can be touched to the starter till it fires off?

The switch is mounted in the dash along with a separate choke switch and T&T switch. I will take some pictures to post in Member Projects. I am hoping there is enough room for the alligator clips behind the dash so that I don't have to pull off the switch. If I go that far, I may as well just replace the switch.

I know the last OMC switch that I wired had about 8 wires coming out of it. I still need Cal to come over with his manual to make sure that one is set up correctly. Might have fried the starter solenoid.

I think that the 71 has a switchbox, so no magneto to worry about.

Merc gurus - any of you have a diagram of the switch so that I don't fry anything messing around?

This ignition has a whole lot more than three wires.
If you know how to reassemble the control box, you can open it up and look for the key number on the side of the ignition switch.

OR

To start and run safely without an ignition switch turned on,...

a) Remove the prop for safety.
b) turn on the water to the muffs or fill the barrel with water.
c1) If no control box is attached, manually shift the motor into Forward gear and be prepared to manually move the top end of the vertical throttle linkage forward just enough to see the carburetor butterfly linkage begin to move a bit.
c2) If controls are connected, leave in Neutral gear and advance the Neutral throttle lever forward.

Then:

1) Dis-connect the (2) yellow wires between the stator & the rectifier & tape off the ends.
2) Connect a set of battery cables between the starter's ground terminal - or any good engine ground point, and be prepared to connect the red (positive) battery jumper cable in a few minutes.
3) Connect (2) small jumper wires (#14 or #16 is big enough)between the positive battery post and one goes to the red terminal on the starboard side of the switchbox & one goes to the white terminal on the starboard side of the switchbox. (leave the existing red & white wires connected to these dame terminals while doing this)
4) Prime up the prime ball on the gas hose to firm. If the carburetors start leaking fuel - stop and fix this before proceeding.
5) lift the manual choke knob.
6a) IF you can safely connect the large red jumper cable from the battery positive to the large terminal on the starter solenoid without risk of it touching ground, connect it, and proceed to Step 7a.
6b) If you can not safely connect the large red jumper cable to the large red jumper cable from the battery positive to the large terminal on the starter solenoid without risk of it touching ground, go to Step 7b.
7a) Connect a small jumper wire to the small terminal on the starter solenoid that has a small yellow wire on it. (later model solenoid wire is yellow with a red tracer - not to be mistaken for the (2) yellow that may have a red tracer coming down from the stator on the 1350 - 1500, etc)
and when you are ready to attempt to start the beast,...
Touch the small jumper wire's other end to the big red jumper cable coming from the battery and the beast will begin attempts to start.
7b)When you are ready to attempt to start the beast,...
Touch and hold the large red jumper cable coming from the battery to the lower terminal on the side of the starter that has typically a large yellow cable connected to it from the starter solenoid.
As you do this, the starter should begin starting the motor.
When the beast starts - move the large jumper cable away from the starter, and make sure it is in no risk of touching engine ground, etc.
8) To kill the engine disconnect the small jumper wire between the positive battery terminal and the white terminal on the starboard side of the switchbox.
DO NOT Disconnect the large red jumper cable to the battery until AFTER the engine has stopped or you will instantly kill the distributor (trigger).
doc F

Ok Thom - you have sufficiently terrified me enough to not try hotwiring it!!! Key in the mail or new switch it is.

Heed the good Dr. well on this one. That ignition system has many sensitive and expensive parts that can be damaged in a heartbeat if the components are not treated correctly and with great care. Not for amateurs, hot wiring one of these. And if you do not consider yourself adept at the art of soldering wires find someone who is before you attempt that switch replacement. It requires a lot of patience, steady hands and the right tools to do the job, it is not something you can do over a few beers.

key ### is on a sticker on the switch housing.

I'm sorry, I guess I wasn't too clear. I meant for you to leave all the wires connected to the ignition switch while jumping. Of course there are more than 3 wires... but just 3 TERMINALS on the switch. You will be doing nothing more than mimicking the switch when doing it this way. Ignition on, then momentarily touch the starter terminal. Leave all wires, including battery cables in place just like they would normally be. But yeah, if you can get a key code, then by all means go that route! Simplest solution.

a good mercury dealer.. may have a set of master keys.. and be able to match up the key.. i know we did in the old OMC dealer i worked at..

When I worked at a Honda bike shop in my late teens, the parts manager had a simple hand tool for making keys. All he did was dial in the key code on a set of small levers on the head of this thing, slip in a blank, and squeezed it just like a big pair of pliers. Snap, in one motion the key was cut. Never seen another one like it. He kept it locked up tight, never would let me touch it... don't know why...

Don't worry everyone - Thom scared my straight. I spent the night working on my lighting in the garage and took some pictures of the switch,dash, and my newest headache - a leaking T&T! The garage is lit up like a Polish church, and here are the pictures:





Is that the key code?







T&T pictures - guess that was why it wasn't working right. Probably no fluid left in the lines

Just got a call from a local dealer 5 minutes away. He has key 134 at $2.10 apiece. Yessir, I will take 3!!! Going to run there right now and then test it on my lunch break!!!

Keyless no more!!! 3 Keys - $6.70. Brought them home and it works in the switch. Got the battery charging and hope to have some video for you guys later tonight regarding "first fire".





Just need to get my ducks in a row so I can try starting it before the Packer game. Man has got to have his priorities straight!!

Somebody help the ignorant - is there a way to set a warm up idle setting with this throttle? I have forward / reverse, and you need to push in the button to get it to move anywhere. I had a buddy with a ski boat where you would hold in button to set the idle. Is this one the same?

It started and ran fine, but I am used to my OMC products where I can adjust the early idle for warmup.



BTW - My daughter and I spent some time cleaning her up yesterday - she is going to shine!!! I will post some pictures under projects when I have more time.

Not familiar with the shift, but maybe like my Force, where you pull out the lever a bit, and then throttle only.

Or, pushing in the button disconnects the shift linkage so you can advance the throttle for warmup. Try holding the button in and advance the throttle, then let loose of the button. If it stays in, and the motor starter engages with the key, should be it. Button should pop back out when lever goes back to Neutral.

AHA!!!! Read the Panel Control text! www.boatinfo.no/lib/mercury/brochures/1967mercuryacc.html#/6

IN NEUTRAL PUSH THE BUTTON IN AND HOLD IT IN WHILE ADDING THROTTLE.

Dropped the LU tonight and took off the top of the water pump. Everything looks solid to me. Tried to get impeller off, and it is on there solid. Any trick to getting it off without damaging anything else? I will be looking at the manual next.

Here are some pics:

use a small chisel and split it near the key way.

Chisel works, also since it's a stainless shaft it's possible the impeller might move if you immobilize the driveshaft then give the impeller a good twist back-and-forth with a set of pump pliers on the O.D. A bit of oil down the center will help too.

Ended up getting it off with a channel lock with the driveshaft in the vice. Came off no problem. Getting the new impeller oriented in the water pump correctly and back on the drive shaft pin was a separate issue, but that was resolved. Getting the LU back on by myself was not happening, but we got it on the next day with an extra set of hands to guide the water tube into the right spot.

Everything ended up working well for cooling, but I was having some stalling issues when shifting into gear. I ended up increasing the idle speed up until it didn't stall, but the idle seems a little high. I need to fix the tach, so I don't have a specific number for what it is running at, but my ear says its a little too high.

Sounds like maybe an idle mixture adjustment on all three carbs would fix that issue. First, get it idling in gear warmed up, then adjust the carbs one-at-a-time.

For each carb, turn the idle mixture needle slowly in (CW) until the motor wants to slow down and stall. This is the "extreme lean" range of the needle. Then turn the needle out (CCW) to richen the mixture until it starts to "blubber" and run rough.

Be sure to allow a little time for idle speed to stabilize before making another adjustment.

Once you find the extreme rich & lean settings on one carb, set that idle mixture needle to the middle of those ranges.

Repeat for each carb. You'll probably find that it's idling fast and "clean" but I expect will bog upon acceleration. That's cause there are no accelerator pumps so you have to run these a bit on the rich side.

So, after you have all three carbs setup as above, move each mixture needle approx 1/8-turn to the rich side (CCW).

See if your hole shot is OK. If so, you're good to go. Adjust idle speed if necessary, then readjust the throttle cable so it has the right amount of pre-load on the cable (i.e. enough to push the throttle arm firmly onto the stop when you lower the fast idle lever).

If the motor still bogs after the first adjustment, try another 1/8-turn CCW on each carb, to richen things up a bit. This should do it, in extreme cases you might have to make one more adjustment, but then you're getting quite rich and it'll start to be cranky.

Anyway, see if that helps,,,,,,,,,,,,,,,,,,,ed

Ed - I did mess a little with the mixture as I noticed that the center carb had the idle need turned out more than the other 2. I adjusted it in (leaned the mix) until they were all the same and I thought that the RPMs picked up a little. I will need to fix the tach to verify the numbers. I will probably post some pics of the tach wiring under Member Projects so you can see what I am working with on the dashboard and the controls up there.

I would not say that the hole shot knocked me out, but with how stiff the cables are it was hard to make any rapid movement of the throttle. I did not take off the carbs or the fuel pumps for cleaning - just bypassed the dirty old gas with a 6 gal tank full of fresh pre-mix and a healthy dose of sea foam. So the dirty carbs might have something to do with how it is all working. I am just hesitant to take too much apart when it seems like I am close. I should probably bite the bullet and give them a good cleaning. If I did, what would the initial idle setting be?

One other thing - when I am priming it pretty typically is dripping gas out of the front of the carb and into the little catch tray at the bottom of the cowling. Is that typical for the Merc's or do I have to work about dirty and needle and seats on all the carbs?

Is it OK to adjust the carbs on the hose, or should I have it in water so there is pressure on the prop? Or get it as good as I can on the hose and then take it to the dock for some fine tuning?

Thanks for your help!!

Sounds like the float/needles aren't adjusted properly or the needle/seat/float needs replacing. Maybe a combination of the above.

If it's not pouring out of the carb when it's running, at least you can test it, but normally you shouldn't get a lot of fuel pouring out the carbs just by squeezing the primer bulb, unless it's already rock-hard and you're squeezing even more (which may over-pressurize the needles, causing leakage).

On the idle mixture, you can only get it close on a flusher. The final tuning has to be done in the water, warmed up, and idling in gear.

Basically the correct idle speed is the lowest speed the motor will idle in gear, and not stall when shifting into gear. If you can get it to idle at 800, that's pretty good. Or even 900-1000.

But 1200 rpm, for example, is a bit on the fast side and it'll clunk when shifting into gear. Hard on the L/U.

A tach is nice, but you don't have to have one to get it set. It's really gonna be what the motor wants.

The most important thing about the carb mixture adjustments is to get each carb mix set the same, then when you make any further adjustments after that, all needles are turned the same amount.

One thing that I've done and you can do, too, is to run the motor in a large plastic barrel and then you'll be able to put it in gear and get a pretty decent adjustment out of it.

You might have to tweak it a bit once in the lake, but it'll be pretty close, especially if you let it warm up a bit. You may need to put some plywood on top of the barrel to keep the water in, and recommend running the hose at a good clip, to keep the barrel filled.

Don't rev it up much or you'll see how fast 50 gallons of water can come out of the barrel! :0

Ok - T&T questions:

#1 - The starboard cylinder is the one that is leaking. I have attached a picture for the cylinder from the 1500 parts list, and I assume that it is pretty similar to the one on the '71 1350.




Looking at the image, it only appears to have a set screw at #5 that could be loose and causing the leak. Are there any other spots - besides the hose connections - that could be causing a leak? I would rather make sure everything is tightened down before assuming all the O-rings are bad and pulling the cylinder apart. I am working on bigger issues right now, but the T&T is next on my list. Would it be faster to take off the starboard cylinder on the 1500 and swap it onto the 1350? No idea if that one is good, but at least I would know it is an option.

#2 - The "Up" button on the 3-way T&T switch doesn't seem to do anything. The "In" button works and pushing both the "Up" and "Up / Out" at the same time works. Pushing just the "Up" switch doesn't do anything. There is not a reference in the service manual for how the "Up" switch works by itself. Just a guess to the gurus - does the "Up" switch bypass the limit switch and allow the tilt to lift up the motor to its max travel height? If not I am wondering if I need to test the solenoid to make sure it is working correctly?

Sorry to ask such basic questions, but it is hard to figure out what needs attention if you don't even know you are operating it correctly!!

63LStriton wrote:

Ok - T&T questions:Looking at the image, it only appears to have a set screw at #5 that could be loose and causing the leak. Are there any other spots - besides the hose connections - that could be causing a leak? Would it be faster to take off the starboard cylinder on the 1500 and swap it onto the 1350? No idea if that one is good, but at least I would know it is an option.

#2 - Just a guess to the gurus - does the "Up" switch bypass the limit switch and allow the tilt to lift up the motor to its max travel height? If not I am wondering if I need to test the solenoid to make sure it is working correctly?S

There are a couple of allen screws which are bleed points, if those are loose you might get a leak. As I recall the #5 screw is a bleed point as well and has an O-ring under it. So if the O-ring is deteriorated it'll leak.

The cylinders are pretty much the same except for the shaft size (as noted in the diagram) but you should be able to swap-in your other cylinder if you can't fix the leak.

On the PT&T, the middle button is used to trim the boat "UP" underway. The limit switch prevents the motor from trimming too far up. So maybe the limit switch isn't working or isn't adjusted properly. You could press on the limit switch button to see if that makes any difference. Or test it by disconnecting the 2 limit switch leads at the pump and, with the motor tilted up so you can get at the switch, press the button on the switch and see if you get continuity with a meter.

Thanks Ed! Wiring and carbs first, but the next time the kids are working on sanding and buffing I will spend some time on the T&T.

As it is I will drop it in for sea trials II this Saturday. Just need to pull the carbs and clean them in the next 2 days. I am thinking that it will perform much better after cleaning and tuning!!!