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Thread: 2.5r Issues

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    2.5r Issues

    I recently bought a 2.5r on the forums that looked like it was in good condition (I replaced the front bearing with an Avid revolution). When I got it the compression didn't seem too high. I tried pinching the sleeve twice, but that seems to have made no effect. I have taken a video of the engine running. Good streak of smoke during acceleration, no bogging or anything. Temps are a bit warm but no too shabby. Is it kapput?

    http://s1189.photobucket.com/albums/...t=MVI_6494.mp4
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    Marshal Double G's Avatar
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    If it is running, then use it! Given the amount of time you ran it, it wasn't long enough to see if it stalls when it gets warm.
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    Quote Originally Posted by Double G View Post
    If it is running, then use it! Given the amount of time you ran it, it wasn't long enough to see if it stalls when it gets warm.
    That's the thing, no matter how high the idle it wants to stall? And when it does stall, the engine floods itself and wont restart. Oh and in the video, at the end, the engine would die unless I stayed on the throttle.
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    Which way is the cutout of the piston facing? It should be towards the carb; same thing with the oiler hole on the rod.
    The Super Derecho

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    Quote Originally Posted by Double G View Post
    Which way is the cutout of the piston facing? It should be towards the carb; same thing with the oiler hole on the rod.
    Yes they are.
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    Quote Originally Posted by Double G View Post
    Which way is the cutout of the piston facing? It should be towards the carb; same thing with the oiler hole on the rod.
    Oh, just realized I never answered your question. When I reassembled the engine, I made sure the piston cutout faced the front of the engine, same with that little oiling hole in the con-rod.
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    It sounds like your LS is too rich. I would retune. Pinch test for about 3-4 seconds after it is warm, then adjust your idle.

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    Quote Originally Posted by chris6414 View Post
    It sounds like your LS is too rich. I would retune. Pinch test for about 3-4 seconds after it is warm, then adjust your idle.
    +1 if that LSN is not right it you will chase that tune forever....
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    What does pinch test? I'm new to this

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    Quote Originally Posted by Cowboyzzz View Post
    What does pinch test? I'm new to this
    It means how much compression your engine has.
    Matthew 7:7

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    Thanks a lot

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    Quote Originally Posted by 1979chevy. View Post
    It means how much compression your engine has.
    The pinch test is as follows. With the engine running and warmed up. Pinch the fuel line. Within 3 to 4 seconds the engine should rev up and die. If it runs longer it is too rich. If it stalls quickly it is too lean. It sounds like your LSN is to rich. Make very small adjustments, 1/16 turn at a time.
    Chevy, The pinch you are refeering to is the engine pinch. The amount of resistance/clearance when piston is TDC. How tight it is.

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    Quote Originally Posted by Powerman View Post
    The pinch test is as follows. With the engine running and warmed up. Pinch the fuel line. Within 3 to 4 seconds the engine should rev up and die. If it runs longer it is too rich. If it stalls quickly it is too lean. It sounds like your LSN is to rich. Make very small adjustments, 1/16 turn at a time.
    Chevy, The pinch you are refeering to is the engine pinch. The amount of resistance/clearance when piston is TDC. How tight it is.
    Meh. I've completely given up on this engine as with my 3.3. The con-rod bushing failed twice in a row, I assume due to the engine not starting. There still is a bit of pinch when warm, but I guess it's just not enough. At this time, I'm really just debating between selling my stuff or buying yet again a new engine.
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    Quote Originally Posted by maxidodies View Post
    Meh. I've completely given up on this engine as with my 3.3. The con-rod bushing failed twice in a row, I assume due to the engine not starting. There still is a bit of pinch when warm, but I guess it's just not enough. At this time, I'm really just debating between selling my stuff or buying yet again a new engine.
    You test the compression with a cold engine not warm....
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    Have you checked your glow plug? If you are destroying connecting rods something is wrong. Its possible that you are too rich and trying to start against a flooded engine. Try taking your glow plug out and turning over engine with car upside down. That will push out any fuel. Make sure your glow plug is good. Set you LSN and HSN back to factory settings. Prime the engine until fuel gets to the carb. Be carefull to not over prime the engine. Also try to preheat your engine with a heat gun or hair drier.
    Also check your rear bearing prior to all the above. When you are fixing your connecting rod. Sometimes when the bearing goes bad it will cause the pushrod to oscilate at a angle. That will cause damage to the connecting rod.
    We have all been to the point of wanting to give up. Hang in there. Keep posting your findings and we will help you get thru it.

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