Topic: 1964 28HP Evinrude starts and dies – Page 2

This topic has 47 replies, 8 voices, and was last updated 2 years, 9 months ago by bob-d.

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June 3, 2022 at 9:01 am #260907
fleetwin
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Like Bill says, I would go through the sync steps again, perhaps the carb butterfly is held open slightly at low/idle speeds. Will the engine continue to run if the throttle is advanced somewhat?

It is easy enough to flip that fuel pump “right side up”, hopefully the fuel lines are long enough. I would install/orient the pump correctly, why take a chance?
June 3, 2022 at 9:43 pm #260947
bob-d
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Ok the saga continues.

Thanks Frank, Bill and Don for the suggestions.

Went through the sync steps again. The new cam roller opened the butterfly a tad early, I adjusted that. The economizer link was way off. Adjusted according to the big Red Johnson manual. Could this be the smoking gun???
Dug into the ignition, and the condensers were reading high at .33 vs the .25-.29mfd range. Ordered new ones as well as new CDI coils , just to be on the safe side. I never tested the original coils when I first got the motor, because it initially ran well, and threw a decent spark on a tester. As part of the restoration I also put in new original J4J’s plugs.
I tried to flip the the Sierra fuel pump to the correct orientation, but when the throttle was wide open it hit the top of the pump? I guess that why the previous owner mounted it upside down. After I see how the rest of the new parts work, or don’t work, maybe I will spring for a new OEM pump. $100….ouch.
Since I was getting backfiring through the carb when I reved up, I decided to look at the packing washers again and add a 2 more to the original 2 on the low speed needle, between the two plastic washers. Good idea? I did notice that the metal needle valve bushing came out with the needle when I unscrewed it. Could this be the source of a air leak, and if so should I seal it up with something like red Locktite?
The motor did run well when I got it last year, unfortunately I messed something up over the winter with my total restoration, where no part was left untouched.
I just haven’t found my mistake yet!
When I get the new ignition parts, I will crank it up and report back.

Bob D
June 4, 2022 at 5:31 am #260952
billw
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Well, when it’s finally fixed, you’ll have a good motor. They were kind of uncommon; but it always seemed like they punched above their weight. You’re doing a great job on it. That is one lucky motor!

Long live American manufacturing!
June 5, 2022 at 12:41 am #260983
fleetwin
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OK, well if that economizer linkage is off, opening the carb way too early, this could be why it coughs/backfires at mid throttle settings.
June 7, 2022 at 10:12 pm #261140
bob-d
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Ok, so I got new coils, new points, new condensers, new OEM fuel pump, checked compression, changed plugs, and took carb apart ( cleaned it with carb cleaner and made sure the float was installed correctly). I adjusted the fuel saver rod, and checked all linkage.
Still have the same old problem. Starts and dies about 5 seconds later. One upgrade I didn’t mention before was that I did change the fuel bowl to the one from an electric start 1965 33HP, so that I could have an electric choke. I used all of the other internal parts from the 28HP carb with the new bowl that had the casting for the choke solenoid on the bottom.
Before I rip the carb off again let me know if this could possibly be a solution. I looked at the parts breakdowns between a 28 and 33HP carb and there were two different part numbers for the nozzle inside the carb bowl. The float part number is the same, as well as the needle and seat. The only difference is the nozzle. Could the 33HP nozzle be mated to the 33HP electric choke fuel bowl, and I have upset the bowl fuel flow by using a 28HP nozzle with a 33HP bowl? This could be a long shot, but I’m running out of ideas.
Thanks,

Bob D
June 8, 2022 at 6:03 am #261161
billw
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Boy, this seems like a GOOD one. I guess if it were me, my next ideas would be:

Pull the fuel inlet hose off the carb and check for smooth, easy flow into a catch container, through all the plumbing, when pumping the primer bulb. (I am thinking about a hose collapsing internally.)

Start the engine, leave the choke on and see if it continues to run. I may be wrong but isn’t it designed to hold a fast idle as long as the choke is out? This would give some idea of whether you’re going lean from low speed circuit flow problems.

If the general mounting stud pattern is the same as the 33, I would temporarily put the entire 33 carb on it and see if the situation changes any.

If there is a run-away vacuum shut down unit on it, I would disable that feature temporarily and see if it stays running.

Without being disrespectful to you or your obvious talents in ANY WAY, how about a picture of how the float is installed? Like I said, I have put them in upside down a few times in my life in a state of total brain-fart and it does very much like what you describe.

Long live American manufacturing!
June 8, 2022 at 12:07 pm #261184
fleetwin
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US Member
Well, not familiar with the similarities/differences between the 28 and 33hp hp carbs, but you can’t even get the engine to run continuously at low speeds, where the nozzle/jet/needle is not an issue. The only other thing that concerns me is whether or not the 33hp models of that vintage used an adjustable high speed needle, or a fixe high speed jet. BUT, I’m guessing you would not have been able to thread your adjustable high speed needle into that carb bowl, if it was meant for a fixed high speed jet.

Have you tried to continually pump the fuel primer bulb while the engine is running to see if that will keep it running? I’m thinking this issue is something relatively simple. Tell us again what you did to this engine mechanically. Needless to say, the cosmetic work you have done looks amazing. I’m also assuming it has never run correctly after the work you have done to it. Did you run it before doing the restoration work? If so, did it run “OK” then? I’m thinking you have checked float orientation and that is OK, but that could certainly explain things.

Anyway of doing a video the next time you run the engine? I’m hearing you say that the engine seems to run “OK” while it is running, but dies after 5-10 seconds of run time.
June 8, 2022 at 2:10 pm #261189
bob-d
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US Member
Thanks Bill and Don for the suggestions.
Ok I went back to basics, (and everyones suggestions) and squeezed the primer ball as I tried starting it, and it kept running for about 30 seconds. As I pumped, it kept the fuel filter filled up with gas. Good sign!
Since the fuel pump, and all related internal fuel hoses are new, I’m going to pick up a new hose, primer ball, and some new connectors, before I dig anymore into the carb.
Maybe getting close?
Thanks,

Bob D
June 8, 2022 at 2:13 pm #261190
dave-bernard
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US Member
could it be the thick round gasket on the center tube? I have found that new ones are to thin.
- This reply was modified 2 years, 10 months ago by dave-bernard.
June 8, 2022 at 2:18 pm #261192
bob-d
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US Member
Here is a picture of the internal fuel plumbing. Let me know if anything here looks incorrect. Hopefully the new OMC fuel pump is oriented correctly?

Bob D
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