1973 evinrude 65hp slow on water ???

[busted-bayliner]

i have a 1973 evinrude 65 hp the boat is a 16 ft glasspar tri hull. On the muffs out of the water this motor runs great heres a video
http://s532.photobucket.com/albums/ee327/lukepatten/?action=view&current=VID-20120420-00001.mp4
in the video the steerin cable was detached hence the motor moving when reving up.
But in the water wide open throttle seems to not get very fast no plane no nothing really just about 15 mphs no bogging or missin from the motor any clues? or point me in the right direction prop maybe? thanks in advance
oh and all throttle linkaage is in spec

heres a pic of what was going on behind the boat full throttle

 

[Rudemen]

Re: 1973 evinrude 65hp slow on water ???

Will the motor run at high rpm's when in water and in gear or does the motor run slow?

 

[Bosunsmate]

Re: 1973 evinrude 65hp slow on water ???

Check that the prop isnt slipping in its bushing by marking a straight line across the bushing and prop and then taking it for a run and seeing if it slips
A 65 should have that on the plane in a flash

 

[busted-bayliner]

Re: 1973 evinrude 65hp slow on water ???

posted a pic of behind the boat

 

[busted-bayliner]

Re: 1973 evinrude 65hp slow on water ???

Will the motor run at high rpm's when in water and in gear or does the motor run slow?

that video was it in gear on the revs

 

[Bosunsmate]

Re: 1973 evinrude 65hp slow on water ???

Have you checked all three cylinders have a firing spark?
Just two firing will get it running like that on the hard with muffs on but it will struggle on the water

 

[busted-bayliner]

Re: 1973 evinrude 65hp slow on water ???

Have you checked all three cylinders have a firing spark?
Just two firing will get it running like that on the hardwith muffs but it will struggle on the water

no i have not whats the best way to do the test and i will go check it right now

 

[Bosunsmate]

Re: 1973 evinrude 65hp slow on water ???

Personally i pull out each spark plug in turn and hold it against a good grounded part of the head with INSULATED pliers and check theres a spark. Theres a few ways to check that its a strong spark ie jumping a large enough gap which there are a lot of posts on this site about but doing the above will at least confirm you a getting spark.

 

[boobie]

Re: 1973 evinrude 65hp slow on water ???

What's the compression on it ??

 

[Rudemen]

Re: 1973 evinrude 65hp slow on water ???

When the boat is in the water, motor in gear and under a load, will the motor rev up to high rpm's and boat not moving much? If so, the prop has been spun and is slipping and will need a new hub or replace the prop all together.

If the motor and boat is in the water in gear full throttle and motor rpm's are low points to a dirty carb and will need to be taken apart and cleaned.

 

[busted-bayliner]

Re: 1973 evinrude 65hp slow on water ???

What's the compression on it ??

havent checked compression will do tomorrow

When the boat is in the water, motor in gear and under a load, will the motor rev up to high rpm's and boat not moving much? If so, the prop has been spun and is slipping and will need a new hub or replace the prop all together.boat

If the motor and boat is in the water in gear full throttle and motor rpm's are low points to a dirty carb and will need to be taken apart and cleaned.

ill clean carbs tomorrow boat does go into high rpms in water

Personally i pull out each spark plug in turn and hold it against a good grounded part of the head with INSULATED pliers and check theres a spark. Theres a few ways to check that its a strong spark ie jumping a large enough gap which there are a lot of posts on this site about but doing the above will at least confirm you a getting spark.

just checked spark on all three cylinder spark is strong

 

[Rudemen]

Re: 1973 evinrude 65hp slow on water ???

If motor runs at high rpm's and the boat doesn't travel very fast tells me you spun the prop.

 

[busted-bayliner]

Re: 1973 evinrude 65hp slow on water ???

did a compression check all three cylinders were between 110 an 115

 

[busted-bayliner]

Re: 1973 evinrude 65hp slow on water ???

ok guys im starting to think maybe it wasnt going at WOT on the lake i had 2 kids and a wife asking daddy why arent we going very fast prop seems fine no slipping but what i did discover today while out side tinkering there is a wire harness coming from under the fly wheel that allows a piece to move with the throttle im thinking this is a trigger wire ? if not let me know please well i noticed the wire goes through a clamp on the block to keep the harness secure some one had it so tight around the harness that it wasnt allowing it to advance the trigger? to it stoppin point ill post a pic would that make the bout sluggish on the water ? pic below
click the pics

 

[Bosunsmate]

Re: 1973 evinrude 65hp slow on water ???

If your timing base isnt free to advance it could well cause your problem.
Hopefully it hasnt crush damaged any wiring in that harness but it looks like quite a good insulating layer on that harness

 

[busted-bayliner]

Re: 1973 evinrude 65hp slow on water ???

If your timing base isnt free to advance it could well cause your problem

is that what that is called

 

[Bosunsmate]

Re: 1973 evinrude 65hp slow on water ???

thats what i call it, and so do quite a few others

 

[busted-bayliner]

Re: 1973 evinrude 65hp slow on water ???

thats what i call it, and so do quite a few others

thanks for your replies feel like a dummy not knowin the terms but im learning thanks again ima try and get out on the water tomorrow ill post results

 

[carterslade]

Re: 1973 evinrude 65hp slow on water ???

I had a similar problem. Discovered that the screw to the linkage to my top carb had fallen out and I was only running on one carb. Just something to check.

 

[Rudemen]

Re: 1973 evinrude 65hp slow on water ???

ok guys im starting to think maybe it wasnt going at WOT on the lake i had 2 kids and a wife asking daddy why arent we going very fast prop seems fine no slipping but what i did discover today while out side tinkering there is a wire harness coming from under the fly wheel that allows a piece to move with the throttle im thinking this is a trigger wire ? if not let me know please well i noticed the wire goes through a clamp on the block to keep the harness secure some one had it so tight around the harness that it wasnt allowing it to advance the trigger? to it stoppin point ill post a pic would that make the bout sluggish on the water ? pic below
click the pics
View attachment 142343View attachment 142344

Because of your Timer Base not traveling all the way to the stopping point on the block explains your whole problem Yes, that wire harness on the right is the Timer base Trigger/Sensor wires, Stator and Charge Coils on the left, two wire harnesses with 4 wires each 8 wires total, 4 wires for the three triggers and the other 4 wires are for the Stator and the three Charge coils. You should be good to go once you give that timer base wire harness a little slack