new boat please help

[garychenoweth]

Hello i just bought a 1976 16.5 invader w/ 1979 evinrude 85hp. my problem is 2 things , one took the boat out yesturday and at wot it just seems to be lacking in power. boat wont plane almost like bogging. also this boat has a manual tilt where should that be set for max speed? any help would be great.

 

[tashasdaddy]

Re: new boat please help

a boat that age could be waterlogged. when was it last run, could have dirty carbs. whats the compression, did you check spark. new or old gas. the tilt has to be experimented with because of load.

 

[garychenoweth]

Re: new boat please help

not water logged, yes new fuel spark...when hit throttle it starts to pick up and then backs back down. i would guess i should get at least 35-mph? but right now much slower.

 

[garychenoweth]

Re: new boat please help

well i dont think it is water logged...there is no visable water in the hull, or bilge.

 

[iwombat]

Re: new boat please help

Let's start with a compression test and a spark check with a proper spark tester set to 7/16". Once we can get some data we can go from there.

 

[ezeke]

Re: new boat please help

As iwombat said, you have to start with the spark and compression tests.

If that boat is the 16.5 Intruder model, the 85 should be plenty to get it on plane if the setup is right.

Find a scale [lots of dumps have them] and weigh the rig with and without the boat. The intruder weighed 1050 lbs without the motor and gear. The 20" motor weighed 288 lbs with no fuel tank and manual Tilt. If you find the boat is much heavier, the flotation may be waterlogged.

I would start with the second set of holes from the transom for the thrust rod.

It would be good to know what propeller you have.

http://www.iboats.com/Invader_Boats__Intruder__1976/bp/64b45356r2

 

[garychenoweth]

Re: new boat please help

do not know what kind of prop....how to tell if waterlogged have no way to get tp bottom end. also does water logged mean junk

 

[ezeke]

Re: new boat please help

The quickest way to tell if the boat is waterlogged is to weigh it. You can also get some idea when the boat is floating empty and still, by the way it sits in the water. You tell what OMC prop you have by removing it and reading the numbers on the back end of the hub.

The orignal propeller choices are listed on the gearcase parts list at the BRP parts catalog for your motor:

http://epc.brp.com/default.aspx?brands=ej&lang=e

 

[garychenoweth]

Re: new boat please help

ok so update..just noticed boat rus running with man choke on.. took it off now boat does not run. checked spark strong blue spark on all 4. none of the carbs are leaking and all 4 bowls had fuel..why woul it run with choke but not with it off.. please help. i dont know anything about boat engines..

 

[garychenoweth]

Re: new boat please help

also just noticed. well let me try to explain. when you engage the throttle to foward there is a thorttle control up close to the fly wheel and one that open the butterflies on the carb. when at full the flys are open but the control by the fly whell only goes about half way "being stop by an adjustable screw..shouldnt this also be open all the way?

 

[JB]

Re: new boat please help

Don't overcomplicate things, Gary.

If it runs bad with the choke on and not at all with choke off you have a fuel problem. Probably dirty carbs, but could be a fuel supply or fuel pump problem.

Fix that, then worry about things you can't do correctly without a Service Manual. You will need the Manual eventually anyway, so why not go get one?

 

[garychenoweth]

Re: new boat please help

i understand but this year evinrude does not have a fuel pump....new tanks new lines ect. but wouldn't getting not enough spark advance cause a bad running motor? i guess that is what i am asking if running at full throttle but half advance = poor running. like i sais man choke down however if use electric choke starts right up while running if hit electric choke dies which seems to be the way it should work right?

 

[Joe Reeves]

Re: new boat please help

Gary.... The engine runs better with the choke on because that is causing the engine to pull fuel into the crankcase that cannot otherwise travel thru the passageways and jets within the carburetors.

The carburetors are fouled, gummed, and clogged. The cure is to remove, clean, and rebuild them with complete carburetor kits.

And that engine absolutely incorporates a fuel pump. Follow the fuel hose that enters the engine to the first component it connects to..... that would be the fuel pump.

And yes, a sticking timer base would result in a poor running engine. If this is your concern, watch the timer base (engine not running but in forward gear) under the flywheel as someone else moves the throttle from the idle position to full throttle.

Now...... clean and rebuild the carburetors.

 

[garychenoweth]

Re: new boat please help

i'm sorry i was told that that motor worked off of suction...anyway what type of price range am i looking at. i have sunk all of my play money into this already so i am just trying to get this working with out the wife killing me you know. and i am sorry if i seemed rude i am just trying to learn

 

[Joe Reeves]

Re: new boat please help

You're not rude and we understand. We've all been there. Carburetor kits are about $20.00 each. The rest is labor. It doesn't take rocket science mentality to do that job BUT it does take a service manual if you attempt it yourself.

When one knows exactly what they're doing, start to finish on that carburetor job (2 carbs), it takes about 3 hours.

Inquire here to see if you can obtain a service manual for that specific engine, and if not, inquire further.

 

[iwombat]

Re: new boat please help

You can also check your local library for a service manual. You won't need the exact year to do a carb rebuild.

And, the fuel pump works off suction so you're partially right.

 

[garychenoweth]

Re: new boat please help

going back to the carbs.. is there a way to see if gas is geeting into the carb with out the motor running?? like if i open the trottle "with engine off" should i be able to see if fuel getting through the jets?

 

[ezeke]

Re: new boat please help

You should not see fuel flowing through the carburetor jets with the engine off.

The fuel pump and primer ball work to fill the float bowls. When they are full, the float rises and stops the flow of fuel. When the engine is running, the pistons create vacuum and pull fuel through the carburetors from the float bowls and then the process repeats itself.

You can see the capillaries on the floor of the carburetor barrel through which the fuel flows. If you were to remove the idle jet covers from the sides of the carburetors, and blow gumout through the jets, you would be able to see that liquid coming through the capillaries. It would in no way be a satisfactory method of repairing a carburetor.

 

[garychenoweth]

Re: new boat please help

ok one more question. can any one tell me the correct firing order? also when standing behind the boat looking at the motor which coils go to what cylinders? the reason i ask is the more i mess with this i dont think it is firing right.

 

[ezeke]

Re: new boat please help

Firing order is 1,2,3,4. Cylinder are numbered in order from top to bottom.

There are two powerpacks. The port [left from rear] pack services 2 and 4, The starboard pack services 1 and 3.

Each powerpack has one orange and one orange and blue lead. The orange and blue lead feeds the top ignition coil on each side. The solid orange feeds the bottom coil on each side. The ignition coils are arranged adjacent to and slightly above the respective cylinders.