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Big Engine Problems

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lilhd

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K guys
I don't know where to go. My "AS" Mach 26 engine is not starting properly anymore. I don't know what happened. When I go to spin start my truck, wholly it takes minimum 5 min for it to turn over and start. But wait, when it's started, I have to make sure I continue to rev it or, lol I'm right back where I started!!!

:Things I've tried/ Checked
-Checked the glow plug (os 8 hot) and it's fine. Tried a cool plug, just for the sake of it and still same thing!
-Checked, carb, cleaned, tightened all parts and replaced carb to a new one
-Checked engine shim (running 20% nitro 12% oil) Nothing different from months of running fine!
-Checked engine clutch and bearings, and replaced with fresh new ones!
- Opened engine and all bearings are good and everything has checked out.

Guyz, my engine is apart and every time I put it back together I get the same 5min of bull$h!@ spinning with signs of turning over, but not until it's ready, I'm stumped LMAO any help/ideas???????? :surrender
 
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When you checked inside the engine did you look at the one way bearing for any cracks. It happened to me a few weeks ago and i didn't catch till i took it apart the 2nd time.
 
Why are you using a cold plug? These type engines normally run a medium to hot plug.
 
Jman30808 said:
When you checked inside the engine did you look at the one way bearing for any cracks. It happened to me a few weeks ago and i didn't catch till i took it apart the 2nd time.
Click to expand...

Yeah, I have checked the bearing and it's good! Still the prob is there :-(

ohmygahitscoby said:
Have you checked your needles? This happened to me before.
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Hey ohmygahitscoby, when you say check the needles what do you mean?

jon2 said:
Why are you using a cold plug? These type engines normally run a medium to hot plug.
Click to expand...

Hey Jon, nice to hear from ya again :-)
As to the cool plug, the os "A5" was just a little cooler for the really cold tempertures we have down here. I "sometimes" run them in crazy cold weather and I fine my truck runs nice with them. However for the most part the os 8 is what I run majority of the time. But when your looking to diagnose a problem, I'll try anything. That's why I tried the cool plug....hahaha
 
engine is either way, way out of tune
or you need a rebuild how many gallons have you ran through it???
the 26 usually lasts like 3 1/2 to 4 depending on how you take care of it...
 
sounds like a tuning issue to me as well, you said you replaced the carb, did you set the needles back to factory settings?
 
bnrpat09 said:
engine is either way, way out of tune
or you need a rebuild how many gallons have you ran through it???
the 26 usually lasts like 3 1/2 to 4 depending on how you take care of it...
Click to expand...

Do you mean once the engine has went through 4 gallons, the engine is done. Wholly, yeah right! I don't even want to believe that! I've went through about 5, and I know I take very good care of my engine. Now when you say rebuild, what parts would you be refering too?
-as far as tuning, I fully agree, I just want to know what else I could try or do since I'm soooo stumped. lol

beason said:
sounds like a tuning issue to me as well, you said you replaced the carb, did you set the needles back to factory settings?
Click to expand...

I put the new carb in for the hell of it cause I wanted to make sure it wasn't the problem, but yes, it was at factory settings.
 
i get more then 6 gallons out of mine and they still run, just not soo good..if you have good glow, your carb settings are right with no air leaks, will eventually start but runs like a three leg'ed chicken, then it kinda sounds like compression. but its hard to tell, try putting a couple of drops of after run oil in the top of the head, and work it around. that should give you a temparary seal around the piston and sleave. if it starts up, then your motor is shot and its time for a rebuild. it will only run till the oil burns out
 
itsalifeworthliving said:
i get more then 6 gallons out of mine and they still run, just not soo good..if you have good glow, your carb settings are right with no air leaks, will eventually start but runs like a three leg'ed chicken, then it kinda sounds like compression. but its hard to tell, try putting a couple of drops of after run oil in the top of the head, and work it around. that should give you a temparary seal around the piston and sleave. if it starts up, then your motor is shot and its time for a rebuild. it will only run till the oil burns out
Click to expand...

NIIIIIIIIICE, now that's something I havn't tried!! Mon I will get right on that and see how it goes. Thx buddy! I'll post the results.

K, I tried it and no real results, so I think I'm just going to rebuild the engine. So I'm looking to get a piston and sleeve, is there anything else I should know since this is my 1st rebuild.
 
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Have you checked your fuel lines?. Might be the line from the tank to the exhaust is split so the fuel is not being fed into the carb properley. Also, your OWB might have oil on it. OWB Lube is good, a couple of drops of it on the bearing and slipping is gone.

If you have a fuel filter check that to see if there are any blockage in the mesh.
 
For the cost of that engine, a rebuild is money in a hole. Typically, a rebuild is at least a piston/sleeve and con-rod. Then your stuck with an old carb, old bearings and old OWB for starting. That's a lot of dough to throw at a $110 engine. You'd be time/money ahead to get a new engine or at most with the current engine, get the sleeve pinched.

Piston/sleeve $44
Con-Rod $34

So, $78 into a $125 engine and you still stuck with old parts.

Doing a $25 pinch (www.rayaracing.com) may be a more affordable solution to eek out a few more gallons of running.

I knew my M26SS lost a lot of pinch by gallon 4. It still ran fine, but liked to be started at about 50% throttle with the pull start. Once running, it was fine. I take care of my engines and average 9-10 gallons before pinching or replacement is needed. I rarely buy engines that cost more the $150 new. Sold it to a buddy for $30 right around gallon 4 as he was in need of an engine that ran reliably. It was all I had. I applied that $30 to the $180 I spent on a new LRP28S3 at my lhs... now talk about an engine that puts a smile on your face ;)
 

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