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Old 10-01-2009, 05:26 PM   #1
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Default Have I damaged my engine....

I have been trying to tune it (my first tune) and it seems to have lost a lot of its pinch. Where before I started today I wasn't able to turn the flywheel over completely using my hand, now it is very easy to do so.

Have I damaged it?
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Old 10-01-2009, 05:28 PM   #2
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if there was a drastic change yea you probly did. did u follow the break-in precedure?
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Old 10-01-2009, 05:38 PM   #3
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Is this a new engine or one you put together? How hot did it get? I ask this because recently I forgot to put the silver shim in my v-spec and ruined the rod in the progress. Does it kinda feel "sloppy" at the top? If so I am willing to bet that your rod just got sloppy witch is better then some things that could of happened.
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Old 10-01-2009, 05:42 PM   #4
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Quote:
Originally Posted by Garet Jax View Post
I have been trying to tune it (my first tune) and it seems to have lost a lot of its pinch. Where before I started today I wasn't able to turn the flywheel over completely using my hand, now it is very easy to do so.

Have I damaged it?
very hard to tell without a teardown but i would venture to say yes if it was a new engine


if its very easy to turn over by hand i would venture to guess its an OS engine
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Old 10-01-2009, 05:45 PM   #5
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Just because it lost its pinch does not mean it is shot. Metal pinch goes away on all engines and they last a very long time after that. Compression is what matters, not pinch. Did you have the glow plug out when you turned the flywheel? Its much easier to turn over with the plug out. Start your engine and run it, if it runs good with good power and idles good your fine
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Old 10-01-2009, 06:14 PM   #6
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Did it get hot, real hot, did the filter ever fall off, is the head loose, glow plug loose? Check everything twice, you get it nailed down
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Old 10-01-2009, 06:56 PM   #7
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Easyryder do you have a scoot????? Cool name BTW.
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Old 10-01-2009, 07:27 PM   #8
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very hard to tell without a teardown but i would venture to say yes if it was a new engine


if its very easy to turn over by hand i would venture to guess its an OS engine
Nice, smooth, low key Vspud bash. I give it an 8/10.
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Old 10-01-2009, 07:59 PM   #9
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Was it hot when it was easy to turn over?
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Old 10-02-2009, 12:20 PM   #10
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OK - Here is an update.

The pinch is definitely reduced over what is was yesterday before I started. even cold with the glow plug in, the pinch is almost non-existent.

I have taken apart the engine and the top of the piston looks to have some marks on it. If you look at the picture, there are 3 concentric circles around the top of the piston. The area in the picture is smooth around those circles where it is ridged everywhere else on the piston.

I have looked to replace just the piston head, but don't see anything but the connecting rod.

I am driving a Werks B7 Pro and wwould appreciate any help in finding a new piston head.

I felt the engine had been broken in sufficiently using heat cycling so I moved onto tuning it.

I started by adjusting the high speed needle and making it leaner until it was hitting a pretty good high end. I may have made it too lean causing the temps to rise.

I then continued by adjusting the low speed needle and the idle screw until it was pretty good at the low end.

While adjusting I was checking temps at the glow plug. The temp readings were never above 230. I have a feeling that this is where my mistake was/is. I believe the temps got too high and I wasn't reading them properly.

If my temps indeed got too high, would the culprit likely be a high speed needle that was too lean or would it likely be something else?

Thanks.
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Old 10-02-2009, 12:59 PM   #11
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Nice, smooth, low key Vspud bash. I give it an 8/10.
just a fact zero , the big bore short stroke design of the vspec will run with VERY little compression .


in case you haven't noticed i don't do too much bashing
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Old 10-02-2009, 02:34 PM   #12
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I run werks engines and if you didn't over heat the engine then put it back togather put a tune on it and run the crap out of it!!!As long as you are blowing smoke out of the corners your good!
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Old 10-02-2009, 08:50 PM   #13
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Quote:
Originally Posted by Garet Jax View Post
I have been trying to tune it (my first tune) and it seems to have lost a lot of its pinch. Where before I started today I wasn't able to turn the flywheel over completely using my hand, now it is very easy to do so.

Have I damaged it?
you are using vague terms, "lost a lot of pinch" and "very easy" to turn over by hand. was there a point where the plug burned out? was there always smoke from th pipe? were you driving up and down a street or on a track? tuning to th street and tuning to a track are totally different. the motor may "feel" bad but if it idles clean and has good power and speed and stays clean on the outside, i say its just finally broken in and the mechanical pinch is gone. if you hold the flywheel and hold the motor horizontal, how long does it stay up before the weight of the motor takes it past tdc? if its less than 10 seconds the piston or sleeve could have gotten scrathced/scuffed, usually due to dirty air filter, they can only hold so much.
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Old 10-02-2009, 09:27 PM   #14
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Quote:
Originally Posted by Garet Jax View Post
OK - Here is an update.

The pinch is definitely reduced over what is was yesterday before I started. even cold with the glow plug in, the pinch is almost non-existent.

I have taken apart the engine and the top of the piston looks to have some marks on it. If you look at the picture, there are 3 concentric circles around the top of the piston. The area in the picture is smooth around those circles where it is ridged everywhere else on the piston.

I have looked to replace just the piston head, but don't see anything but the connecting rod.

I am driving a Werks B7 Pro and wwould appreciate any help in finding a new piston head.

I felt the engine had been broken in sufficiently using heat cycling so I moved onto tuning it.

I started by adjusting the high speed needle and making it leaner until it was hitting a pretty good high end. I may have made it too lean causing the temps to rise.

I then continued by adjusting the low speed needle and the idle screw until it was pretty good at the low end.

While adjusting I was checking temps at the glow plug. The temp readings were never above 230. I have a feeling that this is where my mistake was/is. I believe the temps got too high and I wasn't reading them properly.

If my temps indeed got too high, would the culprit likely be a high speed needle that was too lean or would it likely be something else?

Thanks.
agree with blaze , the piston looks pretty scored like a plug filament had a party in the combustion chamber and then took it to the after hours party through the rest of the engine
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Old 10-03-2009, 06:15 AM   #15
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If there is scoreing in the sleeve or on piston you could have sucked dirt or ran a too lean condition and scored the piston due to broken filament.If this is the case you need to replace front bearing, its cheap so change it just in case.when you have front bearing out check the lateral movement of rear bearing with crank in.If it seems sloppy or gritty when spinning change it also.
Then send it in to rayaracing for a resize.I use him and he does great work and fast turn around time.
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