Question for 225,250,300 4.2 series Yamaha outboards

[Bluefin66]

How are you test running these new motors out of the water?
The book tells you to only use the hose connection and not run the engine. But there are times you need to run the engine like: warming the engine to change oil or test after water pump change, etc. Do I have to build some type of tub to set the motor in, or are there some ears that will work on it? I have never had an outboard motor that I could not test run in the driveway before....

 

[Megabyte]

If you do it on muffs, buy the type with two water inlets (one on each side) and use two seperate hoses.
The big block motors don't move a lot of water at idle, so they need all the help they can get.
Even better would to go to your local farm supply store and get a tub that you can immerse the lower unit into.

Even in the water, my 225 OX66 will sound an overheat alarm if I spend too much time at idle (600 rpm) while the motor is in gear.
My service manager told me that my motor needs about 800 rpm while in gear to cool itself properly and not cause an alarm.

 

[Kris360]

I use a plastic 55 gal. Drum that is cut in half. It is the best way to run the engine out of the water, it give the engine the back pressure it needs to run as it was designed to. When you draine the bucket you will be amazed by the salt and debris that is left.

Megabyte, your engine should not overheat at idle when in the water, the ox 66 is temperamental on the muffs for sure but not in the water.

 

[Megabyte]

Megabyte, your engine should not overheat at idle when in the water, the ox 66 is temperamental on the muffs for sure but not in the water.

Does not overheat at idle while in neutral.
But it will sound an alarm after about 20 minutes at idle while in gear (slow trolling).
Dealer tech said this is normal for big block Yamahas. He says that in gear, they need to be 800 rpm or above to move enough water to keep her cool.

 

[warthog5]

55gal drum cut in half.

Are you cutting it lengthwise and laid on it's side?

My DF-300APX foot will not even come close to fitting in one that stood normal and cut in half....The diameter of the drum is not large enough.

The DF-300APX has a low water pickup on the front of the nosecone, so muffs will not cover that.

I set a 172qt cooler on 2 milk crates and lower the foot into that and run it.

 

[TimC2520]

I use one of these. Picked it up at my local Agway dealer. My 225 OX66 fits nicely in it (and the neighbors are happier now also).


http://www.zoro.com/i/G0299065/?utm_sou ... 7AoddGQASQ

 

[Kris360]

55gal drum cut in half.

Are you cutting it lengthwise and laid on it's side?

My DF-300APX foot will not even come close to fitting in one that stood normal and cut in half....The diameter of the drum is not large enough.

The DF-300APX has a low water pickup on the front of the nosecone, so muffs will not cover that.

I set a 172qt cooler on 2 milk crates and lower the foot into that and run it.

No, not length wise. If you took the drum and put it next to your boat with it sitting on the trailer normally mark it or measure up to the point where it is just under the transom mount bracket and cut the drum. You want to be atleast 2 inches over where the lower unit bolts to the midsection that way the pump will pick up the water easier.

 

[warthog5]

That is kinda my point....The foot is so Big on the DF-300APX....it will not fit inside a 55gal drum. It's longer than the diameter of the drum.

 

[Robert Cibran]

when I had my Yami 250 HP, I used exactly the same as what timC2520 posted, I still use it on my Suzi 175 its the 70 gallon one,,lower unti fit perfectly, paid $100.00 at feed store

 

[POGE]

Try dual side muffs on main pick ups with good hose pressure on each side pick ups and duct tape on lower pick ups to block air being sucked in. This works just fine for maintenance or other test runs on the hard.

I also use a large rectangle chest style from Rubber Maid to place the prop in to run in-gear test too.

 

[Robert Cibran]

another thing I did was get a hose that is 3/4" at HD instead of the cheapy 5/8 green type hose,throws out a lot more water

 

[Bluefin66]

I purchased the 70 gallon tank from Zoro and Timc250 suggested. Just use it today. That is the perfect solution, works fantastic. Thank you.