Break in after rebuild

redstrat

Petty Officer 1st Class
Joined
Dec 29, 2011
Messages
202
After two year on my bench I'm finally ready to start my Force 125. All I have left is to clean and mount carbs, mount the control box, and lync/sync. (Thanks Frank) What is the easiest way to ground spark plugs while setting the timing? I have an extra head that I could ground to the motor but I'm thinking there might be an easier way. After that I'm planning to start it in a 20 gal tub just to see if it runs. After that I'm thinking I will take it to a quiet ramp I have behind my house and let it idle on the trailer for 1/2 an hour, then re-torque the head. After that I'm not sure. What do you guys think about mix ratio, and for how long? RPM limits? Any input will be appreciated. I don't chime in to often but I'm constantly reading what you guys have to say. Thanks

IMG_5564.jpgIMG_5526.jpg
 

pnwboat

Rear Admiral
Joined
Oct 8, 2007
Messages
4,251
Re: Break in after rebuild

This is the rig that I made to ground the plugs when checking spark or timing.

IMG_0775.JPGIMG_0762.JPGIMG_0769.JPG

You can also use a piece of wood and drill some holes for the spark plugs, but you need to run a length wire to each hole to make the ground connection.

For break in, it's recommended to double the amount of oil, 25:1 ratio. I just take it easy for the first hour or so. I don't take it above 4000 RPMs out on the water. I'm sure everyone has their preferred method.
 

Frank Acampora

Supreme Mariner
Joined
Jan 19, 2007
Messages
12,004
Re: Break in after rebuild

AHHH! A white Force. Much nicer than those ugly blue or black monsters. A lot cooler to the touch too on a sunny day. OK--Now put a decal on it, preferably a mermaid.

Well, A couple of six gallon tanks of 25 to 1 and don't consistently go above 3/4 throttle for a couple of hours running time. No hole shots, but a short burst of full throttle while at cruise now and then won't hurt it, as long as you have run it enough to get decent residual oil into the engine. Usually, after a rebuild, I do go full throttle for just 30 seconds or so to confirm timing.

I don't get fancy: To ground plugs, I use a piece of home wiring (romex) ground wire. I wrap it around each plug and put a loop into a plug hole or around another good ground.

AND---Answer me--What is the white pipe like thing sticking out in front of the steering tube?
 

redstrat

Petty Officer 1st Class
Joined
Dec 29, 2011
Messages
202
Re: Break in after rebuild

IMG_5460.jpgIMG_5462.jpgIMG_5552.jpg

Thanks Frank, always helpful. This boat came with a Merc ride-guide dual cable steering. I thought about using a single rack, but then decided to add another steering tube. I had the parts so... what the hey. The tricky part was getting it to tilt far enough to get the travel bar attached. I have to turn the wheel to the left a bit. I'm also planning to make my own angled transom saver. I'm still not sure it will all work smoothly.
 

Frank Acampora

Supreme Mariner
Joined
Jan 19, 2007
Messages
12,004
Re: Break in after rebuild

Ah! Well, I think that hull is rated for a LITTLE MORE than 125
 

redstrat

Petty Officer 1st Class
Joined
Dec 29, 2011
Messages
202
Re: Break in after rebuild

Thanks again pnwboat. Mine is not as slick as yours but I think it will do the trick and I was able to use what I had lying around. Yes Frank the hull is rated for 150hp. It's a 1973. Funny thing is, a couple years later they dropped the rating to 115 I believe. Probably some lawyers got involved.

IMG_5567.jpg
 

redstrat

Petty Officer 1st Class
Joined
Dec 29, 2011
Messages
202
Re: Break in after rebuild

OK, I ran the motor in the tank and she fired right up, I backed it in the water and ran it for 20 min at idle, pulled it out and re-torqued the head. Then, off the trailer and ran it between idle and 1500rpms for 2 hours. The plugs looked clean as a whistle and I re-torqued once more. I then took it out and ran for an hour between idle and 3200rpms. All went smoothly except.... at one point I eased the throttle down and immediately lost a cylinder. I pulled back on the throttle and after about 5min it cleared up and ran smoothly again. I tried again with the same result. I'm thinking I am probably fouling plugs.
So here's my question. I have the carbs set to 1 1/4 turns now. Should I go through Frank's carb setting procedure now, or wait until I go through a couple tanks of double oil mix? Thanks for all your help.

IMG_5568.jpgIMG_5573.jpgIMG_5590.jpg
 

pnwboat

Rear Admiral
Joined
Oct 8, 2007
Messages
4,251
Re: Break in after rebuild

You could probably try to set the idle mixture on the carburetors now, but regardless if you do or don't, you should do the final tune after you've gone through the break in procedure. Also double check the timing just to be sure.

By the way, looks like you've got a nice clean looking rig there.
 

redstrat

Petty Officer 1st Class
Joined
Dec 29, 2011
Messages
202
Re: Break in after rebuild

Thanks pnwboat. I'm taking baby steps here. I don't want to cook this thing after all my hard work.
 
Top