cylinder problems

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gwarden97
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cylinder problems

Post by gwarden97 »

i bought a 1985 Honda spree about a month ago, when i first purchased it it did not run. First thing i did was buy a new battery and it started right up, i changed the spark plug, cleaned the gas tank changed the oil and cleaned the carburator. about a week goes by and now it will not start. i bought a new petcock assembly because i noticed that there was no fuel going from the petcock assembly fuel line to the carb. theres was a very small amount of vacuum suction going on so I'm guessing the cylinder needs to be replaced. before i buy a new kit though i wanted to know what other people thought could be the problem. Also would a big bore kit be worth the money if it was a cylinder problem ?

i appreciate any help given to me :thumbwink:
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vintagegarage
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Re: cylinder problems

Post by vintagegarage »

Low vacuum at the intake pipe can also be caused by an air leak in the bottom end, for example, worn out crankshart seals. I had a Spree that had low vacuum pressure and the left crankshaft seal had come completely out of it's seat in the engine case. My guess at the time was that perhaps a previos owner had sprayed starting fluid into the carb, and a bottom end explosion resulted, blowing out the seal, but that was just my unproven theory. Any chance you used starting fluid to try to start the engine when it first wouldn't start? Let me perfectly clear that I am not suggesting you use starting fluid.. just the opposite. I've found the easiest way to prime the engine is to remove the carb slide and put a few squirts of gas/oil mix into the top of the carb, reinstall the slide and then hit the starter button.
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patthesoundguy
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Re: cylinder problems

Post by patthesoundguy »

If you are wondering about the condition of the top end of your machine, pull the cylinder head and have a peek. It won't take long and you will know for sure. Before doing so get your hands on a compression tester and see what you get for a reading. Id also pull the vacum line from the intake and apply a little vacum to it with the drain screw cracked on the the float bowl of the carb with a container under the carb. If you get fuel flowing freely the petcock is good and you can trouble shoot further. Vacum line should be pulled and suction applied to it to with a finger over the oposite end see if it leaks Sometimes after you re-install a carb the motor can be hard to start from lack of fuel in the carb. Also on the 84 and 85 sprees you have no kick start and if the battery is a little low it will seem to crank over fine but its no enough to start the motor even of it shows spark. Also the idle air mixture screw could be out of adjustment after cleaning the carb. If it started up before you did a bunch of stuff one of those repair things may be your reason for a no start.
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