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72 65hp Johnson/65ESL72

Z

zmany2k

Regular Contributor
Took the boat out for it's maiden voyage with the new floor, carpet, and seats on Saturday. I replaced the #coil first as I've been having issues with the wire arcing to the motor and making it hard to start. She ran like a top all day long. Burned about four gallons of fuel pushing my light aluminum boat all over the Puget sound. Got it home, hooked it to the muffs, fired it up and disconnected fuel line from the motor to let it run the fuel out while pumping fresh water through the engine. Then I rinsed the boat off really good.

Yesterday, I dragged it two hours out to Port Townsend hoping for Halibut and Lingcod. Again, she ran like a top at first. About three miles from the harbor, while running at WOT, she died. Not a slow sputtering death either. I had one cylinder that fired a few times after the other two cut out but I doubt it fired more than two or three times. It was fairly sudden. Tried cranking it back up, nothing. Checked fuel supply, plenty of fuel, pulled the hose off the motor and checked flow, no blockage.pulled the filter cap and checked flow there too. No issues. Tried cranking her again after manhandling the primer bulb a bit and she coughed a bit. After about an hour tinkering while drifting slowly back towards the US side, I got her running by steadily forcing fuel through with the primer bulb. This was tricky as I either had it just right, or I flooded the engine. My buddy drove while I sat in the back pumping away and we were able to get her back in. Just before we got back into the marina, I stopped pumping the bulb to see if maybe it was a blockage that I had worked out by then. She ran fine for about 30 seconds and then suddenly died again. I couldn't get restarted this time so I ended up paddling it back into the marina.

Pretty sure that the symptoms screamed fuel pump, so I pulled it off and tore it apart (It's the old original one that was discontinued a long time ago). Didn't anything apparently wrong with it. The diaphragm looked wore out, but I think I found one spot where it was leaking by the upper spring. I ordered the replacement pump and it should hopefully arrive this week. My question to everyone is this: Anything else that I may have overlooked? The vacuum line appears to be in great shape and none of the fuel lines are leaking. I'm fairly certain that the new fuel pump will fix her right up, just anted to bounce that off of you all.
 
Yes, sounds like a diaphragm problem. Let us know if the new pump cures the problem.

(Running Engine Out Of Gas)
(J. Reeves)

If the engine has but one carburetor, it's unlikely that running the engine out of gas would do any harm. When the carburetor runs out of the fuel/oil mixture, the engine stops running.


However, a engine that has more than one carburetor should simply be shut off. The reasoning is that the top carburetor will run out of fuel first due to gravity and the engine will continue to run on because of the still existing fuel in the other lower carburetors.


This results in having at least one aluminum piston running up and down a steel cylinder wall with improper or no lubrication. Not a good idea!


Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay auction at:

http://shop.ebay.com/Joe_OMC32/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
 
A repair kit would be cheaper and they are available to fit that pump.----Running the carburetors empty of fuel does no damage to the engine and cylinder walls.
 
Last edited:
zmany2k said:
New fuel pump fixed her right up.
Click to expand...

Glad to hear that the new fuel pump cured the problem. As far as running the carburetors dry each time you're thru boating for the day... if it causes the powerhead to fail due to a lean mixture, "racerone" will be there to help you with the rebuild I'm sure. :cool: Ha, snicker snicker :rolleyes:
 
Most folks are not aware of how the lubrication in a 2 stroke engine works;------Oil that is coating all the internal parts does not instantly disappear when one carburetor runs out of fuel !!!!!!!!!!!!!!!
 
I know it doesn't unless it's run for a short while. I'm not sure whether or not it's good for that vacuum powered fuel pump though. Can't think of a much better way to clear most of the ethanol out of my carbs though.

Granted, I've been doing that since you told me about it a couple months ago. Seeing how she runs now with the new pump, I think that pump has been on its way out for awhile now. She fired cold with no choke whatsoever. Ran a little rough until she warmed up, then purred like a kitten. I'll have her out at port Townsend tomorrow for halibut and Lingcod.
 
Ok, after running her a bit today, I have discovered that it wasn't just the fuel pump acting up. It started right up, ran like a top, smooth enough to balance a quarter on the cover once it warmed up (didn't run this well before the fuel pump). Ran it almost a mile out and it died again just like last time. Very sudden, almost like I killed it at the switch. Thinking that maybe it was water in my fuel cans (makes no sense as both tanks were bone dry before I put the five gallons of fuel in them that's in there now, two weeks ago). Fiddled with it a bit, got it running again and cleared the ferry lane before it died again. Thought maybe it was the plugs (NGK-R plugs, roughly one year old), pulled them, they looked a little dirty, but not bad. Cleaned them back up, put them back in. Fiddled with the low speed jets, cranked her a bunch while doing this. She would occasionally cough every five minutes or so.

Went to pull the plugs again to air out the cylinders and make sure fuel was making it into the cylinders. Pulled the #1, it was wet, burned it dry, put it in hand tight and then promptly dropped my only spark plug socket into the 30' deep water that was about 56 degrees. Needless to say, I'm just a "wee bit" frustrated by this point. I tightened the plug as well as I could with a pair of pliers.

There's more to this story of woe and despair, but it doesn't help you confirm what I believe is wrong with it. Me and my buddy (both of us Diesel mechanics) decided that it was probably the plugs. I rowed the whole mile back to the marina with a bit of help from tide and wind (and got a tow from a sail boat with his tiller outboard for the last few hundred feet). Went to load it, realized I left the lights on in my truck, and the truck was dead. Eventually got the boat to a NAPA and got some new plugs for it. This is when I discovered that I wasn't getting steady spark. Tried to pull the flywheel, but couldn't because NAPA didn't have any tools I could use and the ones for sale would've cost me over $100 just for a breaker bar and socket (only had the socket in 3/4" drive). Took it to a Les Schwab around the corner and they let me use an impact, socket and puller to yank the flywheel.

Stator is leaking melted resin on the three big magnets. I'm assuming I need a new stator. Will a bad stator cause me to lose spark if my battery is strong and fully charged (cranked the motor at speed and served to start my truck). What about the timer base? Or power pack? I know someone (was it Joe Reeves?) had a good build for a spark tester.

I'm open to ideas, but taking a break before I test how well it stands up to 300 rounds of 62 grain 5.56mm.
 
Thanks for posting that Diagram for me. Think you posted that for me back in February. Can you explain the DVA adapter to me again? Is it a tool that I need to buy or make? I think you explained this awhile ago, I'm searching for that thread right now.
 
Oh yeah, I'm running a large deep cycle AGM. It's a group 27 size. I'm not running much for accessories either. Just a depth/fish finder and transducer.
 
Thanks a lot. I'm not going to tear into it tonight. Still too mad at it right now. All three charge coils are leaking on the stator. Would like to get this damn boat right before the last day of Halibut season next Sunday. I still have not been able to fish for Halibut. I've tried twice, and both times the boat broke down on me. Granted, I'm pretty sure the stator was an issue the whole time. I noticed the brown epoxy looking resin on the block awhile ago and didn't think anything of it as the boat was still running ok then.
 
So the schematic you posted is the the adapter he made in the video correct? Am I testing A/C voltage coming straight out of the stator? Looks like I need to find a radio shack.
 
Ok. I'll see what I can find. Should have made one when you first told me about it. I'll order the stator tomorrow as it is obviously going or is gone. I'm really hoping to get this back on the water before next Sunday. My son flies in on Saturday for the summer and I'd really like to take him out for Halibut.
 
What causes stators to fail? Is it excessive heat? This motor takes a 6A stator. That's about all I really know about it. I have a dim understanding of the magnetic field generation for the charge coils. Do I need to run more accessories to use the voltage being produced to help ensure a longer service life from my stator?

The stator, timing base, and power pack on my engine are all aftermarket from CDI. The Timing base has a production date sticker that isn't marked. The youngest it could be according to the sticker is dec 31, 2009. Oldest is Jan 1, 2003. I do not know if all three were replaced at the same time, but that's possible. Either way, that's neither here, nor there. The engine is mechanically sound. Block, bore, pistons, crank, carbs, ect, all good to go. Have great compression since I replaced the head gasket back in February. Have perfect fuel supply since I replaced the fuel pump last weekend. Carbs are good and jets tuned right, so I've got air covered as well. Fuel, air, and heat are all you need, I've got no heat.

Mainly, I'm trying to get a good idea on how this system works. I believe the stator uses magnetic field charging to create VAC, which it sends to the power pack/rectifier. The timing base sends voltage from the stator, to the coils via the power pack correct? Those three leads are where I should be checking for A/C voltage correct? At 450VAC? Is 14VDC to the battery how you test the regulator/rectifier?

Believe I just found a local business I can go to tomorrow to get the parts to make a DVA adapter or possibly just buy one.
 
Very briefly, the three charge coils on the stator generate ~300VAC, which is fed to the power pack. A rectifier within the pack changes that to DC and stores it in a capacitor. When it is time to fire a plug, a sensor generates a weak voltage which is sent to one of three SCR's within the power pack. As SCR is an electronic switch. When it is turned on, the storage capacitor discharges it's 300VDC to the proper spark coil. The spark coil increases the 300VDC to whatever it takes to fire the spark plug (thousands of volts).

Your melted charge coils is an obvious indication of the problem here. No way we can say that is the ONLY problem, but you are only spinning your wheels till you replace it.

Check your battery charging rectifier too. They tell me that if blown it can cause overheating damage of the ignition charge coils over time.
 
I didn't know there was another rectifier in the power pack. I'm waiting on a new stator to arrive, hope to have it by Tuesday, Thursday at the latest. So there's no way to test the rest of the circuit until I get the new stator?
 
New stator showed up on Wednesday. Been way too busy to mess with it after work. Should be able to put it on today and hopefully get some water under her as well. Will report what I find.
 
All three (3) large coils on the stator are melting down? Don't bother testing it, just replace it.

The stator on that model would only melt down for two reasons... One being that it is the old type stator which does not have any of the coils insulated with a fiberglass blanket of sorts.

The second reason being that the rectifier has shorted out. This would create a scenario whereas the AC voltage has no access to the rectifier and that voltage would simply back up at the stator resulting in excessive heat. Check the rectifier as follows (remove one lead from the battery to avoid accidental shorting).

(Small Rectifier Description & Location)
(J. Reeves)


On most 2,3,4,6 cylinder engines, the small rectifier is located on the starboard (right) side of the engine just in front of the engines electrical wiring strip. There are a few older V4 engines that have the wiring strip on the rear portion of the engine and the rectifier would be located just under that terminal strip. The smaller horsepower engines usually have the rectifier located on the starboard side of the powerhead close to the carburetor area.


The rectifier appears to be a round object approximately one inch (1") in diameter and also about one inch (1") high. The base of it is sort of triangular in appearance and is attached to the engine with two (2) screws/bolts..... usually one screw/bolt is larger than the other. The rectifier, depending on which one your engine uses, will have either:


One Red wire, one Yellow wire, and one Yellow/Gray wire, or One Red wire, and two Yellow wires.

Note that either of the above rectifiers could have a fourth wire which would be Yellow/Blue

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay auction at:

http://shop.ebay.com/Joe_OMC32/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
********************
(Small Rectifier Test)
(J. Reeves)


Remove the rectifier wires from the terminal block. Using a ohm meter, connect the black lead of the ohm meter to the rectifier base (ground), then one by one, connect the red lead of the ohm meter to the yellow, yellow/gray, then the red wire (some rectifiers may also have a fourth yellow/blue wire. If so connect to that also). Now, reverse the ohm meter leads and check those same wires again. You should get a reading in one direction, and none at all in the other direction.


Now, connect the black lead of the ohm meter to the red wire. One by one, connect the red lead of the ohm meter to the yellow, yellow/gray, and if present, the yellow/blue wire. Then reverse the leads, checking the wires again. Once more, you should get a reading in one direction and none in the other.


Note that the reading obtained from the red rectifier wire will be lower then what is obtained from the other wires.


Any deviation from the "Reading", "No Reading" as above indicates a faulty rectifier. Note that a rectifier will not tolerate reverse polarity. Simply touching the battery with the cables in the reverse order or hooking up a battery charger backwards will blow the diodes in the rectifier assy immediately.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay auction at:

http://shop.ebay.com/Joe_OMC32/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
 
Got the new stator on and the flywheel hand-tight. Can't find my damn torque wrench. Think I loaned out awhile back and never got it back.
 
Uh huh.... I have friends that get mad at me because I won't loan tools or equipment. I still have all of my tools and equipment. :)
 
I went out and bought a new one. Got it torqued down. Forgot to charge the battery back up and now it's charging. Already have the muffs on. Just need to turn on the water and crank it once the battery has a charge.
 
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