300ex question

**mojave** · 09-28-2003, 06:59 PM

i have a 250x with a 300ex engine when i got it it had a bent valve so i peplaced the valve and got it back together and now when i start it the exhaust gets real hot in just a few seconds after about 5-10 seconds my reverse cable was melted to it. is this normal if not what would cause this when i turn it over with my thumb over the spark plug hole it blows fairly warm air. thanks in advance

**ATC crazy** · 09-28-2003, 08:50 PM

Did you set the correct clearances and timing?

**mojave** · 09-29-2003, 10:54 AM

i went to exriders and found a post and set everything how they said

**mojave** · 10-02-2003, 10:29 AM

anybody

**200xman** · 10-02-2003, 12:32 PM

Sounds like it is really lean or the ex. valve is hanging open. Does it idle down or rev really high? Also, are you sure it was at top dead center when you adjusted the valves?

**mojave** · 10-02-2003, 03:14 PM

i replaced 1 valve it was staying open and it didn't have enough compression to start it i went to exriders and found a post that said with the piston all the way to the top the cam lobes should be going down so thats how i did it. when i got it back together i turned it over with my finger over the sparkplug hole and it was shooting out heated air. then i put the plug back in and without the carb on it i shot starting fluid in the intake it started an ran for a few seconds and died so went to put the carb back on and touched the exhaust pipe and it was already extremely hot.

**200xman** · 10-02-2003, 06:00 PM

You are lucky it didn't blow up running without a carb. That is your problem. It should be fine when you put the carb on.

**mojave** · 10-02-2003, 06:03 PM

should it blow hot air out the plug hole like it did without the plug even being in it.

**Lots_Of_Nothing** · 10-02-2003, 06:34 PM

Yes, its the engine saying to you "

, stop running me without a carb, and spraying starter fluid in me".........lol, yes, the engine will get hot as hell quickly without a carb and just spraying trailprotrailprotrailprotrailpro in there to keep it running, not smart....

**84250r** · 10-02-2003, 07:14 PM

I heard putting starter fluid in a motor,it causes it to get hotter then its surpose too. I would just be careful on how much you put in there at one time.

P.s. get that carb back on there.

**mojave** · 10-02-2003, 08:45 PM

well i put the carb on started it it still got very hot but i noticed the carb leaking gas and right around the primer where the bowl bolts on i'm afraid i'm goung to have to get a manual and set everything right.

**84250r** · 10-02-2003, 11:39 PM

Have you had the carb taken apart? When you put back together,did you put new gaskets in? If your running hot,you need to reset the mixture screw. Hows your airfilter?

**mojave** · 10-02-2003, 11:59 PM

no i hadn't had it apart before not until i noticed the gas spewing out every time i hit the gas. i took it apart now and the carb has a crack in it right at the primer. i've never had it running before when i got it the guy told me all it needed was a starter so i got one and thats when i noticed the compression was really low and it needed the valve. its actually a 87 250x with a 97 300ex engine. i think part of the wiring harness is missing i have to jump it at the selenoid because the start button doesn't work.

**mojave** · 10-03-2003, 12:01 AM

i'm really thinking about selling this engine and putting a 350x engine in. has anybody ever done this. how hard is it.

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300ex question