Seafari 20 Power

Bushwacker · #1 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 · #2 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 · #3 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 · #4 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 · #5 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 · #6 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!

Bushwacker · #7 03-15-2015, 11:39 PM

Quote:

Originally Posted by NorthBay

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!

Although the Seafari has more weight forward and is generally better balanced than the CC models, even with the heavy 4-stroke you're planning to use, yes, you will definitely be glad you have trim tabs on the boat! I installed mine in 1978 after my 1st Bahama trip and it was the best $300 I ever spent! Made the boat think it was at least 3' longer! Bennett is a first class outfit with outstanding product support and that 38 year old hardware still works just fine, although I have had to replace the dash control a couple of times. I originally had the joystick-type switch but have switched to the waterproof rocker switch, as I think they are more durable. Spare parts are readily available; and you can download installation instructions, wiring diagrams and troubleshooting directions from the Bennett web site. I would suggest pulling the screws holding the tabs to the transom to insure they are bedded correctly and not leaking into the core, which will also cause crevice corrosion on SS screws. Use a polysulfide caulk like Life Caulk which cures underwater but remains pliable instead of getting brittle with time. The pump/solenoid valve assembly is very durable but make sure the connector in the wiring harness is not corroded. Might be worth sealing with Liquid Electrical tape. And you can use Dexron transmission fluid for hydraulic fluid.

Most folks just think of trim tabs as only being useful for pitch control, i.e. helping stern heavy boats get on plane easier and for helping them stay there at lower speeds as well as help hold the bow down. While all this is true, they are also very useful for roll control, not only to compensate for more weight on one side, but also to adjust the angle of heel to improve the ride. Since I installed the bracket and 25" shaft motor, I find the motor trim is very effective at controlling pitch/running angle, so I mainly use the tabs for roll control.

A deep-V hull will tend to lean into the wind. Reason is wind tends to blow you off course, so when you steer to windward to correct your course, the boat naturally leans into the turn. When the wind is coming from any point forward of the beam, I will often use the tabs to roll the boat in the other direction, away from the wind and waves, which basically increases deadrise of the hull relative to the oncoming waves. If the wind is aft of the beam, I will use the tabs to roll the boat into the wind, again to increase deadrise relative to the following seas to improve the ride. Just a few degrees can make a big improvement in ride. It just takes a subtle tweak of the tabs that not many skippers I've ridden with seem to have figured out, but it's worth experimenting with, as your boat will ride like it's several feet longer!

As for priority, obviously getting the motor running, and fuel and electrical system checkouts will be top priority, but once you start running the boat any distance, you'll definitely want to have those trim tabs working when the water starts getting choppy!