1969 T100c Running Rich

Discussion in 'Technical Help' started by Shabuti, Dec 27, 2022.

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  1. Shabuti

    Shabuti Well-Known Member

    Dec 27, 2022
    28
    68
    USA
    Developed a new oil leak...and its leaking oil at a much higher rate than ever before. But, bike runs good and doesnt smoke so Ill take it haha.

    Should the new head gasket and rocker box gaskets fix this leak or is there somewhere else I should be looking? Its never leaked up through the bolts before, and its under pressure coming out

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  2. Iron

    Iron Elite Member

    Dec 29, 2021
    2,574
    943
    Bob Ross Studios
    I suspect it's those welds in the rocker boxes, the new gaskets will hopefully help.
    Looks to be good oil pressure there but with gas escaping too. Is the engine breather pipe clear and blowing/pulsing when running?
     
  3. Shabuti

    Shabuti Well-Known Member

    Dec 27, 2022
    28
    68
    USA
    The breather pipe is under the rear fender right? Yes its pulsing.

    Also, its leaking ALOT from the head gasket, so much that Im glad I only have a 1 mile commute to work because this is what it looks like after a mile. It never leaked like this until this last rebuild, must have done something wrong.

    But, shes still starting and running good and smooth somehow. Still no smoke.

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  4. Iron

    Iron Elite Member

    Dec 29, 2021
    2,574
    943
    Bob Ross Studios
    Good grief....
     
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  5. Shabuti

    Shabuti Well-Known Member

    Dec 27, 2022
    28
    68
    USA
    So aside from those welds and the gasket you dont think theres anything else that would cause that?

    It was never leaking oil before, so hopefully its just the gaskets. All 4 rocker box headbolts are leaking, and Im guessing the head gasket is leaking and pushing air and oil back up through the headbolts.

    I was joking with this guy telling him that the problem before must have been that it wasnt leaking enough oil haha. Because now its running pretty good leaking all that oil
    She likes it rough I guess.

    Im also going to invest the $100 for a whole new wire harness, as Im guessing I will run into more electrical issues with this old wiring down the road until I replace it all. Iv already rewired half the bike at this point.
     
  6. Shabuti

    Shabuti Well-Known Member

    Dec 27, 2022
    28
    68
    USA
    #46 Shabuti, Jan 18, 2023
    Last edited: Jan 18, 2023
    Ok so this is my final rebuild of this engine for a while, Im tired of doing it haha. I think Iv tore it down and rebuilt it about 10 times in the last 3 months, at least. But on this rebuild, I decided to be very slow and very meticulous doing everything by the book, literally, and making sure every nut bolt and surface was clean and clear of any oil before installing the new gaskets.

    Turns out, I couldnt find a non copper head gasket. So I got a brand new copper head gasket for this rebuild, I handled everything as close to a lab as possible ensuring not to even get the oils from my skin on anything haha. I used the copper spray a gasket stuff that was recommended evenly applied both sides and very carefully installed everything and torqued all the head bolts down proper cross pattern 18 lb-ft that my workshop manual asked for.

    I used new non copper gasket for the rockers, its not paper some kind of alloy not sure. Fought with the damn pushrods a few times, mainly the intake side because the stupid frame is in the way of the headbolt so to get it on I have to move the rocker box and in doing so a couple times must have slipped off the pushrod. Be nice if they made the BOTTOM pushrod seats magnetic and NOT the top. Making the top magnetic makes it alot harder, not easier. But anyway, got it all sorted.

    As of now, she runs alot quieter and smoother. My compression gauge must be broken because it was reading 30psi after install. But anyway, using the old fouled plugs (picking up new ones today) it doesnt take off very smooth but once its going it shifts smooth and even is smooth in low rpm, before it would be jerky.

    Some pictures during rebuild. Still think its a little rich, if new plugs dont fix it may go down in jet size. Because once summer hits it will really be rich if its rich now.

    Doesnt appear to be leaking any oil as of now. Drove it around for a few miles, seemed fine.

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    Long story short I think, amung other issues Im confident that low cylinder pressure was my main cause of the rich condition. Now I think Im down to just fine tuning, as now my tuning screws actually do something!

    I also need to point out that I did NOT anneal the new head gasket. I had done more research, and as I suspected they say its NOT a good idea to use a torch to anneal a copper head gasket as it wont heat it evenly. I guess theres a special oven used to do so. So my recommendation, dont anneal your head gaskets with a torch either have a shop do it or just get a new one and use the spray. Seemed to be my issue.

     
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  7. Shabuti

    Shabuti Well-Known Member

    Dec 27, 2022
    28
    68
    USA
    So update....Bikes still running like new, one to two kick start every day. Problem now is, it appears to still be leaking a slight bit of oil through the head gasket on the left side. Iv noticed, that through every rebuild Iv done, the left side seems to be the one with the most build up.

    Took the bike off the island for the first time today, 10 miles up the road at 50mph at around 4k rpms to the place where I bought it. Rode there and back great, fuel level didnt even change any noticable amount. But, afterwords a little bit of oil in the usual spot appearing to come from the left cylinder where the head gasket is.

    No oil anywhere else, everything else is spotless dry. So Im wondering if those welds on the rocker are the issue. I cant find replacement rocker boxes anywhere.

    So the question is, do I leave the oil leak alone since its so minute, or should I attempt to have the rockers re-welded to try and fix it? Will the oil cause any other damage aside from excess build up over time? It isnt burning any that I can see, if so its very minor. No smoke.

    On the up side, the guy I bought the bike from round the original exhaust the bike came with. So I plan on cleaning that up and installing it, as I planned on eventually putting the standard T00C scrambler exhaust back on it anyway like it should have. Maybe sell the T100R exhaust that was put on it.

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