Seafari 20 Power

cdavisdb · #1 01-16-2015, 05:45 PM

You should get better than 2 mpg with the 150. I had a 20 seafari with a 150 black max of about 1978 vintage. We loaded the boat very heavy(3 divers, 9-10 tanks, 100-150 lb ice) most of the time. I don't remember exactly what my fuel consumption was, but for sure it was a little better than 2 even when loaded heavy. 45 gallons was enough(barely) to run 40 miles offshore and back, plus idle around for 6 hours or so. When it was light, fuel consumption went way down,

Bushwacker · #2 01-17-2015, 08:17 PM

Quote:

Originally Posted by cdavisdb

You should get better than 2 mpg with the 150. I had a 20 seafari with a 150 black max of about 1978 vintage. . .

I agree that any of the smaller V-6 Mercs will burn less gas than the old cross-flow OMC's, so would be a good choice if you can manage corrosion issues. I bought my V-4 in 1975 because there were lots of 20 year old Johnrudes running around then but I never saw any Mercs more than about 5 years old.

GameOnSalmon · #3 03-05-2015, 02:33 PM

Northbay,
Don't know if you got this up and running yet with the cold snap going on. Denny hit the nail on the head. That 150 is Notorious for carbon build up.

If the motor has not been De-Carbed and has been sitting for awhile its time to knock it out. I would suggest a couple of things to really help that.

First off Use Seafoam and do a Super deep De-Carb. I actually take the Airbox cover off and fire up the engine on the hose and shoot Seafoam straight into the carbs several times. Then Load it up good and kill the motor. Let it sit for about 15 mins. Fire it up on fresh fuel from an auxillery tank and run it for a few.

I will do this 2 to 3 times. Once you have done that.

Pull all 6 spark plugs and check your compression then? If you have good even compression I would then suggest Rebuilding the carbs before you run it out much. Just my 2 cents and no change required.

Good Luck.. One of my Favorite Engines you have there.

Robert

NorthBay · #4 03-12-2015, 07:55 PM

Thanks for the reply Robert. The decarb did not solve it unfortunately. Actually, after retest of compression, I can't get numbers as high as the originals. I decided to go with the yamaha f115. It passed a leak down test and is running well. picked up a lower unit and tested it yesterday. It is mounted on a novurania 18' RIB that is in pretty poor shape and I am getting the seastar steering and controls/instruments as well. I am basically going to strip the Novurania down and get rid of it. I have a lot of work to do to the seafari before the motor goes on...mostly cleaning, painting and rigging. Looking forward to it!

GameOnSalmon · #5 03-13-2015, 01:03 AM

Quote:

Originally Posted by NorthBay

Thanks for the reply Robert. The decarb did not solve it unfortunately. Actually, after retest of compression, I can't get numbers as high as the originals. I decided to go with the yamaha f115. It passed a leak down test and is running well. picked up a lower unit and tested it yesterday. It is mounted on a novurania 18' RIB that is in pretty poor shape and I am getting the seastar steering and controls/instruments as well. I am basically going to strip the Novurania down and get rid of it. I have a lot of work to do to the seafari before the motor goes on...mostly cleaning, painting and rigging. Looking forward to it!

Northbay,
Dam that sucks... was really hoping that Decarb would do the trick for you. The yamaha will be a great engine. You did exactly what I do. Buy the whole boat... pull the engine, and part out the boat and trailer.

If u are installing steering... The 4.2 No feedback Cable is more than enough for that 115. I could not fathom a reason for installing a Seastar Hydraulic steering if its not needed. Just more things to go wrong on the water.

I have run the No Feedback Set up on a Johnson 225 ocean runner and it worked great. If you like eating Spinach forget the Hydraulic for a 115 not needed....

Keep us posted.
Robert

NorthBay · #6 03-15-2015, 07:07 PM

You are likely right about the steering...I have always preferred cable. I may be able to reuse the steering from the Johnson but I haven't got to check it out yet. It is missing the steering wheel so that does make it tough to turn! The seastar is in good shape but I would need longer hoses so either way I am going to be spending something.

I might have to give that solas 4 blade a try...the prop on the motor now was pushing a really light boat and looks to have a lot of pitch. I have no experience with 4 blades.

I hope to get started stripping the boat down next weekend. Thanks for the suggestions guys! I appreciate it.

NorthBay · #7 03-15-2015, 08:19 PM

I've got another question I've been meaning to put to you guys...my Seafari has bennett trim tabs and the small hydraulic tank (it looks rough and is bone dry) but is missing controls. Do most folks use trim tabs with the seafari? Should repairing/replacing be on my immediate list when i put her back together? Thanks!