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mlts22's avatar
mlts22
Explorer II
Jan 12, 2016

Worth seafoaming a Yammy 3000 iSE before replacing carb?

Due to real life events (layoffs, friends and relatives in ICU) , I have not had time last year to do the usual upkeep on things as I should normally.

Pulled out the generator, starts at full choke after a number of pulls, and surges at no load. Add 750 watts... still surges. Add 1500 watts, smooths out, and after 2-3 hours, when the load is removed, the generator works fine (econ switch on or off.)

Had a friend of mine rebuild the carburetor. Not sure how thorough a job he did, though. Since I started a new job, and in the process of cleaning a lot of stuff out, (not to mention a renaissance faire), I don't have the time and table space to rebuild the thing myself, which is why I'd just buy a replacement, Onan-style, rather than try a rebuild.

So, before I pay the three C-notes to buy a new carb assembly, is it worth tossing four ounces of Seafoam in the tank with a gallon of gas, and letting it run, or would that just waste fuel?

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  • Sam_Spade's avatar
    Sam_Spade
    Explorer
    Jan 29, 2016
    mlts22 wrote:
    For a real cure, it takes pulling the carb, soaking it in solvent, and blasting open the jets with compressed air.


    Very often that is not the case.

    IF you use a real cleaner with real proven solvents in it.....instead of a product designed to be a stabilizer and just happens to have mild cleaning ability.

    Berrymans B12 Chemtool is a good cleaner. Seafoam is not.

    You must do what you think is right but tearing the carb apart often is NOT required if you just use a good cleaner.
  • mlts22's avatar
    mlts22
    Explorer II
    Jan 29, 2016
    I do appreciate the advice. If the repair place can't get if fixed, why throw good money after bad?

    If the SeaFoam treatment doesn't do the job, I'm probably going to recommend fuel additives be used stabilizers, to prevent varnish, as opposed to something which can actually do something about it. For a real cure, it takes pulling the carb, soaking it in solvent, and blasting open the jets with compressed air.
  • John_Joey's avatar
    John_Joey
    Explorer
    Jan 28, 2016
    Sam Spade wrote:
    John&Joey wrote:

    I was actually hoping mlts22 would do a follow up.


    The odds of him making a reply would have been MUCH higher if you would have addressed the question TO HIM.....or quoted his post. ;)


    Appears not to be the case.
  • Sam_Spade's avatar
    Sam_Spade
    Explorer
    Jan 28, 2016
    mlts22 wrote:
    it is wise to have the shop get the generator starting on the first pull (or twist of the starter)... then go, item by item, down Yamaha's checklist.


    Yes, correct.

    My point is that it is NOT wise to do it the other way around; that is, give them a list of the things you want serviced without mentioning the basic problem.

    You might be surprised at how many people do that, often from advice garnered in places like this, and then go back to pick it up only to say "But it is still hard to start and surges".....with a bill for several hundred dollars only to find something like a cracked head or that it needs a valve job or rings and is not worth fixing. But you still have a bill for the service that you requested.
  • mlts22's avatar
    mlts22
    Explorer II
    Jan 28, 2016
    I do have written notes about what I did and their outcomes. This way, I have a decent checklist of what is done, what wasn't, and what went neglected the past year.

    The issue is fairly straightforward (hard to start, surges), but since the generator has so many hours on it, it is wise to have the shop get the generator starting on the first pull (or twist of the starter)... then go, item by item, down Yamaha's checklist. The Yamaha 3000iSE (well, right now, it is functioning like a 3000iS until I replace the starting battery) is not cheap, but that generator has "earned its bones", so having it overhauled is a good thing.

    I rarely see generators get used for more than a few hundred hours, so 2500 hours on a genset is pretty surprising. It also has been remarkably quiet.
  • Sam_Spade's avatar
    Sam_Spade
    Explorer
    Jan 28, 2016
    mlts22 wrote:

    It will be assumed that they do the usual diagnostics to fix the issue,


    BAD assumption.

    You need to explain the "issue" and tell them you want that fixed.
    Then if you want additional routine maintenance done, tell them that TOO. The two may not be related at all.

    YOU MUST BE SPECIFIC or there is a good chance you will end up disappointed with the results.
  • mlts22's avatar
    mlts22
    Explorer II
    Jan 27, 2016
    The reason for the cylinder decarbonization and such done by a real shop is that the Yamaha manual states it needs to be done.

    It will be assumed that they do the usual diagnostics to fix the issue, but the manual specs some additional items like valve lash that need adjusting. Especially with the long hours the generator has run.
  • Sam_Spade's avatar
    Sam_Spade
    Explorer
    Jan 25, 2016
    mlts22 wrote:
    I did similar to this with the B12 (where I also ran it through, shut things off for an hour, then restarted), with not much difference made.


    The cleaner needs time to SOAK.

    I suggest that you get it hot again and then leave it sit for 24-48 hours before you give up on the cleaner.

    The odds of Seafoam helping when B12 did not are about ZERO.
  • Sam_Spade's avatar
    Sam_Spade
    Explorer
    Jan 25, 2016
    mlts22 wrote:

    The problem is that it used to always start on the first pull. Now, it seems to not like life.

    have them pop the heads and have them do decarbonization of the piston, and other maintenance tasks that I can't really do myself,

    Again, what killed it was the fact that I wasn't able to fog it,


    Is it safe to assume that you have checked the operation of the choke to be sure it is doing what it should ?

    If so, I think that you TELLLING the shop what to do is a mistake.....because they will do exactly that whether or not the real cause of the problem is on your list. It is usually MUCH BETTER to let them diagnose the problem and tell you what needs to be done to fix it.

    And lastly, your failure to squirt a little extra oil into the cylinder before it went to sleep for a few months likely has NOTHING to do with your present problems.

    Changing the plug first is a good idea.
  • Ron3rd's avatar
    Ron3rd
    Explorer III
    Jan 25, 2016
    mlts22 wrote:
    Ron3rd wrote:

    My 11 year old Honda EU2000 was doing the same thing and Seafoam cleared it up. Worth a try fist. Keep in mind the Seafoam might need some time to work, like a day or two.


    Should I toss in SeaFoam, run a tankful through, drain the carb bowl, and when I come back next weekend, check the results? I did similar to this with the B12 (where I also ran it through, shut things off for an hour, then restarted), with not much difference made.


    I would give it a double dose of Seafoam in the fuel, run it for 10 or 15 minutes, then let the Seafoam/fuel sit in the carb overnight and see what happens. Keep at it and you'll probably get it cleared out. Mine didn't resolve itself right away.

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