1972 Mercury 1400 140 hp outboard motor won't start after towing it home

[raesha59]

My husband and I bought a boat with a 1972 Mercury 1400 140 hp outboard motor some time ago. It worked just fine (started without trouble) when we went and looked at it/bought it. We brought it home (about a 250-300 mile trip) and my husband has not been able to get it to start since bringing it home. We took it out to the lake and NOTHING! It wouldn't start! What a disappointment. So we brought it home and he has tried to figure out what is wrong with it. He is mechanical and fixes all our vehicles, lawn equipment, tractors etc but boat motors are new to him. (He is a truck driver so has very limited time that he can work on it) I know he has checked all the normal areas to check (I, however am NOT mechanical) so I thought I would try to see if I could possibly get some suggestions on what else he should look at/do. He has wondered about some sort of safety shut off switch, but have no idea what it would look like or where to look for it. (He has tried!) Does anyone possibly have any suggestions for me to share with him the next time he comes home so HOPEFULLY THIS YEAR we might actually be able to take her out onto the water and get some fishing in? Thank you.

 

[Barnacle_Bill]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

We took it out to the lake and NOTHING! Does that mean the starter wasn't even turning over or it was but wouldn't fire? There may be an emergency kill switch on the remote. If tripped the motor will turn over but not start.

 

[raesha59]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

As I remember, it did turn over, it just would not start. All it would do it crank and crank. So if there is an emergency kill switch (which is what my husband suspects) where would he look for it and what would it look like? Once found, can it be reset or does it have to be replaced?

 

[raesha59]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

I did find and purchase a repair manual for him online. Still waiting for it to arrive.

 

[Chris1956]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

He should test compression and see if he has spark on each spark plug. Post back with results.

 

[raesha59]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

I believe he already did that, but I will pass the info along when he comes in. Thanks to everyone for all the replies and assistance. At least now we have something to work with instead of just looking at the boat sitting in the back yard and wondering what to do! (That would be me! LOL) I can't wait to get her out on the water and spending some good quality time with my hard working honey!

 

[merc850]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

Here's how you start it : pump fuel line bulb until it's hard, lift small black lever on inside of control box to about 3/4 full position - turn key and hold down black choke button while cranking motor. There is a neutral interlock in the control box so make sure engine control is solidly in neutral (straight up). I suggest removing all cowlings so you can see what is happening.

 

[CharlieB]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

The stacked 6 cyl motors LOVE fuel, they require a LOT of choke to start.

Slow cranking speed can contribute to hard starting, make sure all battery cable connections are clean bright and tight, both ends, including the starter cable.

If all else fails, rig a windex type spray bottle with pre-mixed fuel and give a straight shot into each carb. It should not need this if the choke is working.

 

[raesha59]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

Ok people, thank you for all your suggestions. I am talking on the phone to my husband and he said there is no fire to the plugs. He has already tried all of the above suggestions. Does anyone have any other suggestions? He's thinking it has something to do with the kill switch that was mentioned, but still doesn't have any idea what it looks like or where to locate it. Any ideas?

 

[CharlieB]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

Most O/B have some type of switch on the control that some type of clip and lanyard are attached, when pulled off the ignition dies.

If this is still on and still no spark then he will need to troubleshoot the ignition.

CDI Electronics has one of the best Troubleshooting guide, free

ISSUU - CDI Electronics Practical Outboard Ignition Troubleshooting by CDI Electronics

The early Merc battery CD ignition (distributor) uses a CD module. The red wire should be 12V always, white should be switched 12V by the ignition switch. The guide will tell him which wires to disconnect and ground to test the module and coil, If both pass the spark test then most often the trigger in the distributor is suspect.

New trigger is available from CDI Electronics thru their website.

Because there is NO RETURN on electrical parts, make SURE he repeats all tests. Any problems, questions, repost, please post his results as others may be having the same problem and may benefit from your progress.

 

[calvinator]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

On the throttle control box there may be a kill switch by the key.

For example, here is my Mercury Commander 2000 control box:



See under the key there is that metal shield... Under there is a kill switch. It must be in the up position for the ignition to fire.

 

[Chris1956]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

If he has the original MerControl, it does not have a kill switch built in. Someone may have added one to the boat, likely on the dashboard. CharlieB has the right approach to troubleshoot the ign.

 

[merc850]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

This is the 1972 control box, no kill switch unless PO put one in - no spark means electronics not workingthis diagram is similar except for tach wiring, 12v+ power on red and white on switchbox, the trigger test is done on the wires on the other side(black,white,brown).Take the distributor cap off to check for corrosion etc. but do not try to pull rotor off shaft.

 

[kazek]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

I am not sure if 1972 year mercs had tilt kill switch on the distributor side just above switch box to prevent engine firing out of water.1975 merc 850 has one on the side of engine and neutral interlock switch.if switch on the side of engine exist,then disconnect it from distributor side of switch box.other ways trigger needs troubleshoot procedure.how is electrical wiring?older mercs are know for wires going bad

 

[raesha59]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

Thanks to everyone for their input! I will definitely pass all responses along to him when he gets in off the road. (Fingers crossed he'll be able to figure it out with all of your help and we'll be on the water before we know it!) I will definitely post what he finds after implementing all this advice. Thanks to everyone for their generosity of sharing their knowledge. It is greatly appreciated!

 

[raesha59]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

Just to let everyone know, hubby is home and out working on it to see if he can get it figured out right now! (Keeping fingers crossed!) Thanks again for all the input. I sure hope SOMETHING works!

 

[raesha59]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

Ok, update on this motor. The manual that I ordered for it came in. After going through all the tips and hints everyone gave, studying the book, testing this and that and a lot of research my husband discovered that the wiring harness is bad. Step 1! Wiring harness has been ordered, came in today, but hubby is still on the road so now we have to wait for him to get home and put the wiring harness on and see what happens. However, he took his manual with him in the truck and has faithfully been searching and studying it. HE FOUND THE 'KILL' SWITCH! (In the book) So, now my question to you is this....I have been trying to locate the "Mercury Tilt Stop Switch" online in an effort to try to not only locate one (just in case, lol) but to get an idea of what it might cost. I'm not having any luck so far. Any suggestions?

 

[turtles11756]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

very important to hook up the battery cables positive to positive. neg. to neg. check over every wire from inside the control box (key switch) to the last one at the choke on the motor.the insulation merc used was not the best and they all rot. i think you are looking for the "merc switch" which is a safety item that would cut out the motor if it struck something underway and tilted up to an unsafe position . i don't think this is why you have no spark. keep at it it will fire and when it does hold on ! then go over all your fuel lines if they are the originals they will need some work. all the service manuals have useful info, cymler, seloc, glenn's, the mercury being best and can be found cheap used on ebay. marineengine.com lists a parts diagram for old motors going way back

 

[Chris1956]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

That Mercury "Tilt Stop" switch will be located on the starboard side of the top cowling support, very near the switchbox. It should be blue plastic, about the size of a standard ignition condenser.

 

[CharlieB]

Re: 1972 Mercury 1400 140 hp outboard motor won't start after towing it home

I rely on the Merc parts site (with Pictures) you need the model and serial #'s

The #1 web site for genuine Mercury Mercruiser engines, parts and propellers

You can find every part, position, (available or discontinued) and last dealer price. Once you have the factory part # you can cross reference it on iBoats and all the other suppliers. As far as fuel primer bulbs and quick-disconnect fuel fittings, a lot of owners won't use anything other than factory, the aftermarket often do not have the quality of those two items. Most everything else is fine.