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75 hp Johnson Stinger 1977

Hi thanks for you’re reply. Compression is 119 on the nose for all 3 cylinders. Did test after running it in driveway on muffs for 15 minutes. It does not come back when pumping primer bulb. I have used ethanol fuel in past but this year rebuilt carbs and replaced fuel lines and used no ethanol since. Have not ran it on water without co yet. Gotta get it out and run it soon! I live in Michigan and that’s were I bought the gas. I did not replace high speed and low speed orifices
 
Hey Joe probably shouldn’t have done this but I lifted the timer base off the block without marking its location. Anyway the plastic white ring on the bottom is cracked. Is it supposed to be? Also does the lip of the white ring sit flush on the motor?
 
Siniscta said:
Hey Joe probably shouldn’t have done this but I lifted the timer base off the block without marking its location. Anyway the plastic white ring on the bottom is cracked. Is it supposed to be? Also does the lip of the white ring sit flush on the motor?
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The timer base will only go on one way... no special location, the linkage takes care of that... think about it.

The white spacer, bushing sits in the groove of the timer-base with the smaller ridge portion down. The ring needs to be compressed when installing the timer-base so that the ring seats in the top housing of the powerhead.

Cracked? Is it cracked or not? You need to be the judge of that. The ring is a "Split Ring" and is designed that way.

Lubrication.... a slight bit of grease on the brass bushing..... a light coat of oil only on the white ring.
 
Yep Joe had em also plus all the mircoficshe for motors back to the late 50"s, along with Mercotronic tester,steven flywheel magnetizer and growler and ton of old special tools that went up is smoke......
 
faztbullet said:
Yep Joe had em also plus all the mircoficshe for motors back to the late 50"s, along with Mercotronic tester,steven flywheel magnetizer and growler and ton of old special tools that went up in smoke......
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Yeah, that's all true bullet... including the smoke. After I left and went with a different dealership, the manager of the first marina where I started my career quit and moved to Florida. Strange it was that the day he left, the entire place burned to the ground, taking all its financial records with it. What a coincidence!.... lots of smoke!.... BUT... How did you know? Hmmm!
 
I think Pappy is another one of your followers. You guys "been there" for sure. Only dream about those good old days now, but this 77 Stinger is fun to work on for sure. The one I did carbs on today has 55D's, I didn't take out the low speed jets to clean, just ran "CRC Throttle Body Cleaner" through with correct size welding tip cleaners. milled flat the float bowls as the previous "hack" had ground them up with some kinda "rotary" power tool while cleaning the bowls.....what a mess, then over tightened the 4 screws. Sync was way off......I guess it was at some 65 dollar per hour shop, that put in the new floats and gaskets, then hacked up the rest.......WTF? Tomorrow I will rebuild the CMC trim/tilt......full of rust, motor frozen up. I think I once heard the owner ask me if I had time to "tune up" his pontoon boat? Gonna be a $1200 "tune up". "Professional" shops won't work on anything older than a 2000 model year, so that loads up home based "shade tree" mechanics and welders like me. There were 3 others like me here in Duluth, one taught school too.....excellent mechanic, Mr. Fairchild, but they are all retired now. I send work to Gene's Marine in Cloquet, but they are 3 to 4 weeks out right now. This marine business is awesome right now for anybody that's honest and skilled. A chance to work at home for great pay.
So did you perform those diagnostics with your new DVA? Sounds like you changed your trigger/timer already? I found a good used one here today, then set it down, now I can't find it....dah! No, you shouldnt have to replace the orifices unless they are messed up. Make flat the float bowls with 180 or 220 good quality wet/dry paper and lubricate, (soapy water, gas, whatever), as your milling on a nice sturdy flat surface. Set floats a FEW degrees above parallel to carb body when holding upside down the carb body. Allow adequate float drop so the float can just barely meet the bowl bottom when it is observed with carb in operating position. Easy to measure but be sure to consider gasket too. Now keep away ethanol and run all fuel out of engine when storing boat for over 1 month. Michigan is "on the fence" yet for mandating E10. Ask your retailer whats in their tanks. For now only Minnesota, Missouri, Montana, Oregon, Pennsylvania, Louisiana, and Washington have mandates in place. Florida and Hawaii have "bailed" (no longer mandated but many retailers still may carry it), and Maine has "banned" the stuff.
 
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Hi Timguy.

No I have not performed the DVA test yet because I took the carbs off again. Some people are convinced it's fuel related so I decided to look over the carbs again. I'm new to all this so I 'm learning by he minute. I have a service manuel and that's been helpful but still I lack all the experience others have. I decided to replace the low speed and high speed orifice plugs but I guess I probobly could've take them out and soaked them in carb cleaner. Probobly wont make much of a difference new or old clean ones. They all looked good except the one low speed orifice that got suck. UGGGGGG! Yes I have the special tool! I don't think it's a fuel problem. I rebuilt carbs, new fuel lines, fuel pump, and primer bulb. The timming base is not sticking. Anyway how far in do I put the "screw plug" in the carb (the screw that goes in after the low speed orifice plug)? Also how tight do I screw in the low and high speed orifice plugs. I'm guessing just snug them up. Correct? I have to wait on some parts now before I test her out.

Thanks Tim
 
Just snug in the orifices reasonably and then when you put in the plug cap screw with gasket tighten that up snuggly as well.
 
faztbullet said:
Not a follower but that is what happened to me!!!!Didnt know you had the same ordeal !!!!
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Ok. Using a highly recommended ignition troubleshooting site online I performed this test. Remove 2 yellow wires from rectifier and if you get a good spark the rectifier is bad. I did this and cranked the motor 2x. First time no spark and the second time strong spark that jumped a 1/2 inch. So is the rectifier good or bad? Would this cause my problem? Happy 4th to all!!
 
racerone said:
The compression would be " good " if it showed 140 PSI----What does your gauge say ??
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joereeves said:
If pumping the fuel primer bulb constantly by hand, acting as a manual fuel pump, causes the problem to cease... the cause of the problem would be in the fuel system, not the ignition system (faulty fuel pump?), however...........

Do a close visual check of the stator under the flywheel. If it should be dripping a sticky looking substance down on the timer-base and powerhead area, that would indicate it has encountered a meltdown problem. That would result in a AC voltage drop to the powerpack capacitor which, in turn, when hot, would result in weak, erratic, and eventually no spark.

A stator in the early stages of this type failure may very well function properly when cold, but when hot loses its voltage production power.

Also, check the timer-base to see if it has a tendency to stick, more likely to take place when the engine is hot rather than cold... BUT... when cold is also possible.

Fouled carburetors will also result in having the engine fall on its face, so to speak... BUT... carburetors do not come and go, back and forth. If they're faulty, they stay that way... so this being the cause is unlikely.
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Pull the flywheel and check the trigger (timer base)
 
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