1967 650 wont run under load

[coloradorookie]

Hello all, <br /><br /> I need help,i have a 1967 650 65 hp merc type I ignition, magneto and points, that wont run under load, heres whats been done:<br /><br />carbs rebuilt by reputable well recomended dealer,<br /><br />new fuel tank, line fittings, primer hose etc, filter as well<br /><br />linkages checked by pro, adjusted as well<br /><br />leak down down by shops as well, <br />they said less than 5percent on all 4<br /><br />but i just cant get it to max out under load.<br /><br />prop is fine as confirmed by three separate local prop shops, only a "12"<br /><br />boat not all loaded, 16'5" bow runner,fiberglass<br /><br />but i just cant get it to run fine on the boat, test tank she blows the water out, has 3 mechanics confused. i know cars not boats, but i suspect the coil and or points, does this sound about right, is there a way to test the coil if i pull the magneto assembly? bought a seloc manual no real help.<br /><br />hate to scrap it but is it worth paying to rebuild it or am i missing the obvious?<br /><br />thanks all!

 

[WillyBWright]

Re: 1967 650 wont run under load

Welcome to iboats. <br /><br />You can see if they're all firing with an inductive pickup timing light. Clamp the pickup on each plug wire on successive test runs. Tape the trigger on and place the light where you can easily see the flash. If the light is flashing, it's getting spark.<br /><br />It sounds like you've taken care of the likely external sources. Internal problems may be all that's left. The reed blocks have grooves that hold oil when the motor is running. This provides a seal between the two cylinders each reed block serves. When they wear down, it loses that seal and gasses slip by. It would require a powerhead teardown to replace them.

 

[Clams Canino]

Re: 1967 650 wont run under load

And if the thing will idle OK, then your reed blocks are *not* worn enough to be a real <br />factor. Willie, please mention that when you go about singing gloom and doom via reedblocks? I don't have the time to catch them all and correct them. <br /><br />When you say 12" is that a 12 PITCH?<br /><br />That boat may be heavier than you think, I had a 17' bowrider and a known good 80hp Merc and it could not plane the boat out unless you moved to the front. Is the motor trimmed all the way down (in) ??<br /><br />60hp is a bit small for a runnabout unless it's real light. Is the motor trying to spool up?<br /><br />-W

 

[coloradorookie]

Re: 1967 650 wont run under load

the leak down test was done twice, and i was told the cylinders were in excellent shape. i am really leaning towards te coil and points, wires, ut before i spend 200 dollars i need to know it wil work, thus i am trying to find out how to test the coil.<br /><br />as far as weight, there is nothing in the boat at all but me, gas and battery, and a 28 lb trolling motor can push t easily.<br /><br />the prop is a 12 inch pitch, but the motor will not rev up in gear at all, i suspect less than 2000 rpm max in gear, i even had the gearcase checked to make sure the gears were correct, all ok. <br /><br />no luck.

 

[coloradorookie]

Re: 1967 650 wont run under load

i am really concerned that i am throwing money at a dead horse, i have three motors, and need one to get me on the water, a 40 hp, maybe small for the boat, this 65 hp, which i would love to have run, and an 85 hp chrysler not run in many many years, may be too heavy for the boat.<br /><br />i want a decent family fish boat,but NNNEEEEEDDDD to get out on the water, so my put the 40 on it for now.<br /><br />thank you all for your help, and if anyone could tell me how to test this coil, it would be appreciated.<br /><br />remeber, runs perfect in neutral and on/in a test tank kicks the water right out. nothing on the water though, feels like you were not giving it throttle, and the throttle stop screw and cables were checked, as well as the control box rebuilt, it was ok too.<br />has several mchanics stumped.

 

[Clams Canino]

Re: 1967 650 wont run under load

Sounds like something is not letting it spool up. I don't think it's terminal. See my timing and synch post on this board and verify it all yourself. Your max advance outta be 34-35 degrees. With a motor that old it's hard to find someone who really knows the critters. were it here I'm sure I could get to the bottom of it pretty quickly. Since the compession and leakdown is OK, it's worth fixing. If the plug wires aren;t sparkling in the dark and pass an ohm test they are OK. Ohm the plugs too, I've seen them break in the inside. <br /><br />Also know that my 80hp on a 17' boat was also empty. But I'd think with a 12 pitch prop the thing really outta spool up in your case.<br /><br />-W

 

[coloradorookie]

Re: 1967 650 wont run under load

i can do that, just so i know what would be good compression, what ohm's should the wires be, and how would i know if the coils is bad, is there an ohms' test for it?<br /><br />i saw your profile, couldn't hapen to hav a good magneto for my mtor would you?<br /><br />LOL<br /><br />thanks so much for your help, wish I was closer to you so we could get it going.<br /><br />thanks again, by the way the manual doesnt have coil or compression stats to go by.Socom that is.

 

[coloradorookie]

Re: 1967 650 wont run under load

found it ...<br /><br />bad coil, had burn in shielding, sparking to the magneto.<br /><br />thanks to all for your help, new to boats<br /><br />thanks million clams, you the man.!