powerhead swap need finishing touches

caphank

Cadet
Joined
May 10, 2004
Messages
18
posted June 02, 2004 03:25 AM <br />--------------------------------------------------------------------------------<br />I finished the engine transplant and ran the engine. It sound real good. This weekend I plan to test it out in the water. I'm bringing a timing light to set the timing and a voltmeter to read the charging voltage. Anything else I should bring? A couple of observation I noted while running the engine. When I rev it up I noticed a small mist of fuel coming from the upper jet screw(?) area. Is this normal? When I snychonize my linkages, should the motor be running? The manual doesn't really give me a starting point but, do I line up the the mark on the cam to carb's throttle lever first and then set idle screw or do I set the throttle cable adjustment first? Or should I leave it along if it runs okay? Thank for any info guys. Talk to you later. Caphank
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: powerhead swap need finishing touches

Yes, possibly. Well, maybe. But then again.....<br /><br />What motor is this anyway?
 

caphank

Cadet
Joined
May 10, 2004
Messages
18
Re: powerhead swap need finishing touches

Sorry about that. It is an 1985 Evinrude 40hp electric/remote with vro. I had a bad #2 cylinder so I swapped powerhead with another identical engine that had a blown lower unit. I rebuilt the carbs, new plugs and wires, fuel hose, and fresh gas. I'm ready to make final adjustments. Timing light and voltmeter I have. How will I know if I need to adjust cables and linkages? Thanks for helping.
 

caphank

Cadet
Joined
May 10, 2004
Messages
18
Re: powerhead swap need finishing touches

Need more advice and suggestions. I got a 1985 rude 40hp vro(disconnected)electric remote. I swapped a good used powerhead and every component that was attached to it to my engine that had a blown cylinder. Took it out for first test run. Engine started easily after priming and a few cranks. Tried to make all necessary linkages and timing adjustment according to the manual. Engine idle fine and sound smooth. So far so good. Shifted into gear and started out at 2500rpm. No problem. Taking my time I got out of the harbor(thirty minutes)and I gradually open her up. Throttle up to 5000 rpm but I wasn't going fast. Then I pushed(forced)the throttle further and the boat just took off. I saw the tach hit 7000 and I backed it down to 5500rpm. I'm cruising now for a few minute @5500 thinking I fixed the problem and I fishing again until the engine started to "surge", tach needle wavering, engine power bucking. Get the picture. Double check all settings and tried different timing settings. No change. But before I came in I remember what you said and when I squeezed the primer bulb the power always return and engine would run smooth for a few minutes. I did this procedure all morning and it never failed. Fuel filter always full. Power restored each timer after pumping bulb.<br />As suggested by several masters of Iboat here's what I did beforehand. Portable fuel tank w/fresh gas, 50:1 mix, can of Sea-Foam, new fuel line w/ bulb, new fuel hoses in engine compartment,and new spark plugs. I took apart four carbs to inspect and clean, using solvent and a thin wire to clear the passages and needles. Believe me, there nothing in those carbs now. I took apart one fuel pump for inspection and it look brand new, held vaccuum and manually I can pump fuel out. As I mention above, the coils and power pack and wiring etc. all came with this engine.<br />What scares me is this might be the same problem I had two years ago that might have lead to the damages to my original powerhead. I don't want to go through this again. How can this be? Original problem still there yet every component got inspected, replaced or swapped. Where or what did I miss? Caphank
 
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