67 3hp Yachtwin timing

1967 Yachtwin 3hp, folding leg model purchased two weeks ago. I know nothing of its history, other than it won't run, and it appears someone tried to rebuild it. When I first got it home, I set it up over a barrel and got it to fire, it did not run very strong, but it did run. It didn?t pump any water so I stopped.

Next weekend I replaced the impeller and tried to start again, got only a weak response, it would sort of run with drill spinning it, but could not sustain itself.

Today I set points using the VOM, first with the throttle lever at WOT, got nothing, discovered that the points just open as the piston starts to go down

It appeared to be timing too retarded, so I redid the points with the throttle in the stop position.all to the left. With this setting it will almost run. With the drill spinning it will go along firing but it still seems that the spark is happening too late. I checked the piston travel and the points open just at the piston reaches TDC, not while it is still in compression stroke. The plugs were warm when I pulled them after this latest failed attempt to start.

It appears that someone previously did a rebuild, everything is clean and new, I only needed to replace the float and the impeller. The person I bought it from bought it non working and passed it on w/o making any efforts to get it going.

It really seems that the timing needs to advance a bit more. Beside using the VOM I set the points at .020, and even .030 to no avail. Is there some other way to advance the timing a few degrees that I, being a complete outboard noobee, am unaware of?

Thanks for your help
Mike

Re: 67 3hp Yachtwin timing

jmo, but you should set the points at wot. have a look at leroys ramblings.

Re: 67 3hp Yachtwin timing

There is no timing per say but::
Be sure the breaker point cam is installed with side marked top up.
You need to check the crank and flywheel key ways for damage and note if the key is damaged.
When assembling; the crank and bore need to be clean and dry.
There is a timing fixture to set the points so they open exactly alike.But the motor will run fine with carefully adjusted points.
Flywheel nut tightened to 30-40ft lbs.Coils should be installed with the ends of the laminations even with the bosses on the armature plate.

Re: 67 3hp Yachtwin timing

http://dl.dropbox.com/u/7758645/keyway.jpg

maybe this is the answer, I saw another photo that didn't look mangled like this one. Is this a major problem or repairaable?

thanks

Re: 67 3hp Yachtwin timing

It really doesnt matter where the throttle is when adjusting the points.

Anyways, is there spark? Have you tested it with an inline tester set to 1/4"? If present will it jump the gap with a bright blue ZAP!!?

What is the compression?

As stated, the timing is not adjustable. There are 3 air gaps to adjust though, plug gap (030), point gap (020) and coil air gap (as described above).

Also ensure that the throttle plates open at the correct mark.

BTW, what is going on with the breaker point cam? Can you take a pic with it off?

Re: 67 3hp Yachtwin timing

I just bought an inline tester from the local NAPA dealer, a made in China affair, I get a bright orange spark.
The coils seem to not have any adjustment. I have taken them out and replaced them a dozen times. I can only get all three screws in with it in one position. Plug and points have been set as (you) described.
I do not have a compression tester, am borrowing from a friend this week

I will try to get the breaker point cam off tomorrow and post the photo.

Re: 67 3hp Yachtwin timing

The coils are definately adjustable. Minor adjustments can make a difference.

If you look at them, you will see the shiny bosses on the armature plate beneath them. Run your nail along the edge of the coil lamination and boss, and pull the coil fore and aft until it is perfectly smooth and your nail doesnt catch. I have a pic of this somewhere on my hard drive, Ill find it.

There is a tool that a member on here makes (F_R) that helps with this, PM him if you are interested.

Re: 67 3hp Yachtwin timing

Armature plate? Here what the coils screw to
http://dl.dropbox.com/u/7758645/outboard/top 1.jpg
http://dl.dropbox.com/u/7758645/outboard/top 2.jpg
http://dl.dropbox.com/u/7758645/outboard/top 3.jpg
photo's repositioned to change the shadows. Is this the armature plate?

COIL:
http://dl.dropbox.com/u/7758645/outboard/coil.jpg

Crankshaft
http://dl.dropbox.com/u/7758645/outboard/shaft 2.jpg
http://dl.dropbox.com/u/7758645/outboard/shaft1.jpg

breaker point cam, top and bottom. The slot is damaged, the little pice to the side came out with the cam. The cam doesn't wiggle and can't be positioned but one way.
http://dl.dropbox.com/u/7758645/outboard/timing cam 1.jpg
http://dl.dropbox.com/u/7758645/outboard/timing cam 2.jpg

and just in case it shows something, here is the side of the engine
http://dl.dropbox.com/u/7758645/outboard/side 1.jpg
http://dl.dropbox.com/u/7758645/outboard/side 2.jpg

I appreciate all the help you folks are offering me. Thanks
Mike

Re: 67 3hp Yachtwin timing

Hi Mike. These links can walk you through and entire ignition rebuild and set up. Holler if you get stuck.


http://forums.iboats.com/showthread.php?t=506678&page=2&highlight=spark+plug+wire

http://www.outboard-boat-motor-repa...on 3 HP 1952-1967 Ignition System Tune-up.htm

Re: 67 3hp Yachtwin timing

thank you kfa, I've spent a lot of time all ready with the second link, and the Clymer manual. Up to this point I am working with parts of unknown age, but they all look new/never used. it appears I am not the first to struggle with this outboard. I may order new parts next weekend, but I have spark, i (appear to) have compression, and fuel. It sure looks to me like the spark is firing too late.

Re: 67 3hp Yachtwin timing

Yes that is your armature plate. If you look at the outer 2 mounting screw holes for the coils you will see the vertical flat edge just past them. Those are the edges that you need to make sure the edge of your coil laminations is lined up with.

Do you have a pic of after you installed the coils/condensors/points?

Re: 67 3hp Yachtwin timing

no picture at the moment, everything is still in pieces. But I did just do a check of how I have been placing the coils and I have been doing it correctly, they lie flush.

After cleaning the breaker cam i find it has a very small amount of play, my guess is it is about the thickness of a typing paper or less, .004, but I would think no play is desired.

When the lever is in the off position, the carb is shut and the armture plate fully retards the spark. When the lever is all the way WOT the timing advances along with the carb opening. Am I misunderstanding something here? Even with the WOT setting the piston is at TDC when the points open. Shouldn't they open a few degrees before?

Of course, no compression would also give no power, so I am trying to find a tester to confirm what my thumb over sparkplug hole says is OK.

Re: 67 3hp Yachtwin timing

THE ANSWER
borrowed two compression testers, they both say #1 25#, #2 50#

it looks like rings at minimum are in order. Shame whoever started all this didn't check that first, me too, for that matter. Anyone have part #'s for the rings or do I need to know more?

thanks again folks

Re: 67 3hp Yachtwin timing

That will do it. We have all been there, thats why we reccomend checking compression as the first thing you do when you first get an outboard.

What you do now is pull off the bypass covers and inspect the rings. Maybe they are stuck, maybe broken. Stick a little screw driver in there and try to push on them, see if they bounce or not. Then pull the head if need be. It is also possible there is a rip or something in the head gasket around the bottom cylinder. That would be an ideal situation for you. Dress the head and install a new head gasket. But wont know till you have a peek.

Let us know what you find.

Re: 67 3hp Yachtwin timing

Now I know how many pieces are in a Yachtwin power hear.

Looking in through the exhaust port the rings seems stuck so I started taking things apart. Pulled the piston out, and like everything else on this engine, it looks good, and the rings were not stuck.

However what passed for the crankcase gasket looked more like tin foil and it wasn't very thick at all, so the problem maybe was fuel mixture being pushed out there rather than into the cylinder.

I now have a basket case and am off in search of a new set of gaskets. All of them do not look as new as the rest of the engine, so whoever did this may have tried to reuse the old ones and that came back to bite him in the....

Part numbers anyone?

thankyou

Re: 67 3hp Yachtwin timing

GO to www.marineengine.com for parts list.

The crankcase halves dont use a gasket, I use 3M 847 on them. You likely just needed to do the head gasket, but ah well, you have her apart now

Dress the head to ensure she is flat before reinstalling.

Re: 67 3hp Yachtwin timing

Another possible problem

The crankcase casting, one of the bolt holes in a corner is broken a bit better than in half, I don't see how that is going to allow a good seal. I left my camera on the boat so I can't get a photo, but I am thinking this was a great exercise and I should pick up another 3hp yachtwin I was offered for $50 and put it on the folding lower.

Re: 67 3hp Yachtwin timing

I bought a new, but older, 3 hp non folder to get the crankcase casting from. Here is a picture of how mine broke, that way when I took it apart. None of the bolts attaching it were tight, by comparison with the older engine, so I think it may have been leaking around the crankcase. There had been a tin foil gasket applied to that joint.

I contacted marine engine.com, as suggested, they do not have an online parts chart for my folder, but Joe did give me a price for all new gaskets and a head gasket. He did not respond to the question about the water return gasket, see here, here and here The older engine has a straight copper tube, this one, as you can see, is a 90? angle and is somewhat damaged, though is still carries water. I am guessing the ethanol in the fuel will not do this any good. Are there any options for replacing?

I am thinking this folder may not be repairable, awaping a working power head might be the answer.

Anyone?

thanks
Mike