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Old 05-13-2008, 10:42 PM   #1
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Default Internal engine troubles

Ok, once my piston hits the top of the sleeve it kinda locks itself there. then I can move the flywheel back and forth about 1/4 of a rotation both ways.

The little piece in the engine that the piston arm hooks onto seems to be loose inside the piston arm or something, is this fixable or what? whats wrong?

My engine ran fine, then it stopped and I tried to start it but it wouldnt start, and it sounded very weird when I was pulling the PS. I finally got it to start and it would hardly move at all. At one point I was WOT and the car just stood there.. idling.

If that description is as bad as I think it is you guys will need a video, which will be posted tomorrow.

Thanks
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Old 05-14-2008, 12:22 PM   #2
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Ok, Ive got the video, now how/where do I upload it?

Turns out its something wrong with the conrod I think, but Id LOVE your guys opinion on what it is and how to fix it... if it is fixable.
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Old 05-14-2008, 12:27 PM   #3
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It's your con rod. There is slop in the bushing that causes that play at top dead center. DONT try to start it anymore. You will just cause more damage. Order a new rod. But first open it up and look at where the rod connects to the crank. See if that is the case. If it is not then look at the top where the rod connects to the pin. Hope this helps!
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Old 05-14-2008, 12:33 PM   #4
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Originally Posted by slaytanic View Post
It's your con rod. There is slop in the bushing that causes that play at top dead center. DONT try to start it anymore. You will just cause more damage. Order a new rod. But first open it up and look at where the rod connects to the crank. See if that is the case. If it is not then look at the top where the rod connects to the pin. Hope this helps!
Yeah I think it is the conrod. It also causes play when its a BDC. Ive already driven it around wrecked like this, a little bit, which def contributed to the damage.

How/where would I order one for a LRP .28 Zspec3, can it be any conrod or does it need to be the EXACT size.

NVM^^, Im hoping this will work, http://cgi.ebay.com/LRP-38231-ASSOCI...2em118Q2el1247

ps: How do you get the crank out, or the bearing out? How do I get the conrod off the piston? If my engine doesnt have much compression left, should I replace the sleeve? or just get a whole new engine?... Ive only had about 3 gallons through my engine, but they were 3 hard gallons, I just found out ive been running super rich the whole time It is only a 170$ engine... where most "decent" engines cost 300-500$ so did I buy a lower quality engine or was I too hard on it or what?

and what are these cool blue things that go into the carb insert? what do they do? http://cgi.ebay.com/LRP-Z-28R-28-Spe...2em118Q2el1247
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Old 05-14-2008, 12:44 PM   #5
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I believe with the LRP z28 your best option would be to get the piston sleeve rod combo. Less trouble anyhow.

For break down.

1. Take off your back plate, Head and head button.

2. put a zip tie into the exhaust port. NOTHING METAL!!

3. Rotate the engine. the zip tie will push the sleeve up so you can remove it.

4. With the sleeve out put your piston to top position. You should now be able to pull the rod off the crsank pin easily.

5. Pull the piston and rod out the top.

Finished! Repeat in reverso to install new set. While you are at it I would go ahead and seal your back plate!

Those pretty blue thingys are carb restictors. The will restrict airflow to help improve runtimes. You will probably need to lean your engine a bit if you use one. Mainly for racing. If you are bashing then run the biggest one you got! Which is usually stock. Hope this helps!
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Old 05-14-2008, 12:49 PM   #6
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awesome, thank you so much for the help, unfortunately I already knew how to do all that stuff you posted

Im curious how I get the crankshaft out now, not that I would/need to, just the curiosity is killing me.

have you ever seen the piston/sleeve rod combo? where can I get one?

I am bashing, and stock is no carb restrictor... is that what I want?

How do I seal my backplate? whats the purpose of that?

My engine was practically filled with a black sludge, which I believe was a mixture of unburnt gas, and "green goop" that I put into the PS one way bearing. That black sludge was all over the engine, backplate, PS, everywhere.

Thanks
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Old 05-14-2008, 12:58 PM   #7
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Once you have all that stuff out the cranke will slide right out the back.

As far as sealing your engine. Do a search and you will find it. Would take too long to type. Too put it short use th red hi temp gasket in a tube stuff. You can find it at the auto parts store, Put a small bead around the case where the back plate goes on. There is alot more you can do though it all is pretty much the same process for different parts of your motor. I seal ALL my motors before I even fire them up just in case. Can save you tuning headaches.

Run whatever restrictor it came with. Or none if it came with none.

I didnt look for a psr combo for that mill. Just assumed they had one as most "budget" mills do have those. Not banging the z28 though. It is a raped ape for sure
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Old 05-14-2008, 01:08 PM   #8
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Quote:
Originally Posted by slaytanic View Post
Once you have all that stuff out the cranke will slide right out the back.

As far as sealing your engine. Do a search and you will find it. Would take too long to type. Too put it short use th red hi temp gasket in a tube stuff. You can find it at the auto parts store, Put a small bead around the case where the back plate goes on. There is alot more you can do though it all is pretty much the same process for different parts of your motor. I seal ALL my motors before I even fire them up just in case. Can save you tuning headaches.

Run whatever restrictor it came with. Or none if it came with none.

I didnt look for a psr combo for that mill. Just assumed they had one as most "budget" mills do have those. Not banging the z28 though. It is a raped ape for sure
Ok, Ill try to slide it back, see if that works.

I dont know if I need sealing, I never have tuning issues and it runs awesome, ridiculous power.

It didnt come with a restrictor, I dont use one, I would like it to go a little faster though

I dont think im gonna be able to find the things I need to rebuild a LRP .28... I might just buy a whole new LRP .28 or a diff .28 engine, it HAS to be PS though....

raped ape = very fast motor?

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Old 05-14-2008, 01:54 PM   #9
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Raped ape = Violent power fun in it's place. Almost uncontrollable. I had one I bashed with and it was FUN. Would hang with anything out there.
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Old 05-14-2008, 02:08 PM   #10
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Quote:
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Raped ape = Violent power fun in it's place. Almost uncontrollable. I had one I bashed with and it was FUN. Would hang with anything out there.
Ok, I thought so because it does have insane power, especially in a buggy. Ive also got a 18t clutch in it so it is ridiculous. Like you said, almost impossible to control, very fun though when youre doing 95% throttle, then you go to 100% WOT and it STILL spins the tires!
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