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Aaaaahhh! Engine won't turn over!

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Lessen

Lessen

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Ok, I'm starting to get a bit disgruntled. Here's the deal. Not too long ago I sent my O.S. RG piston and sleeve to get pinched. I've finally got around to "attempting" break in today. Well, simply put... it won't turn over. It get's stuck every damn time no matter what I do. I'm using an AE starter box and I had it hooked up to my car. I heated the engine with a hair dryer, I loosened the glow plug (various degrees), I made sure that when the starter wheel made contact the flywheel could turn as much as possible before compression is reached. I made sure the engine had ARO oil for lubrication. Nothing. I did this like 5 or 6 times today and it get's stuck everytime. And yes, I tried it with my car running. Actually on that attempt (final attempt) the racheting sound I heard was the starter box belt that started skipping. I have no idea what to do... I need help.
 
Only thing I can think of is maybe pulling the plug, dropping a bunch of ARO in there and hitting the box for awhile to lap it down a bit. Sounds to me like the pinch is really tight. Maybe try that with a hair dryer or heat gun blowing on the head?

That, honestly, is about the only thing I can come up with. I'm sure someone has a better idea, but thought I'd throw this out there all the same.
 
I had the same problem with my Ninja. I ended up heating the mill up to about 145 degress to get it to start. The hotter, the better. Make sure you have already primed the fuel up to the carb. Keep at it.
 
145. I'll take note of that temp. When did you take that temp Rob? After my final try I took the head completely off and took a direct temp of the piston. At that point it was only around 107 or so but that was after I had taken the engine off to manually turn the flywheel then reinstall it. So I'm guessing I only had it up to 120 or so. I don't have a heat gun, just a hair dryer.. will that be sufficient if I just heat it for like 5 minutes or something? Honestly, I was suprised how quickly it got warm with a hair dryer. Guess i just need to heat longer... I'll try again tomorrow probably. Thanks guys!
 
I used a hair dryer for at least 10 minutes directly on the crankcase. I measured the temp at the plug like I would while running. I also had the truck sitting in the sun and it was about 85 degrees out that day.
 
Who did your pinch Lessen,

If nothing works it could be Overpinched, and RayAracing can fix it. http://www.rayaracing.com/faq.htm In the first FAQ they say they can fix over compressed sleeves, I know not what you wanted to hear. I hope you can figure it out, I would hate to have to send my stuff out again.
 
OS Rocket will also releave it for free if he's the one who did it. I found that out after the fact.

I took my engine off, took the bell/flywheel off then hooked it up to a 120v drill on the crank where the clutch bearings sit. My 12v cordless wouldn't turn it over either. Then I sat and had it run on the drill with the engine in one hand and the drill in the other running the drill as fast as it would go. I ran it like that for about half an hour while spraying wd-40 down the carb neck every 30 seconds or so. I had taken the carb off to avoid damaging the seals with WD.

That was an OS 21 RG-X. I couldn't get it to turn over with the pullstart when the engine was temped at 150 by putting it in the oven.

End result, an engine that would still get stuck at TDC and require a screwdriver prying at the flywheel to get it over. It did that for over a gallon. It still has decent pinch 4 gallons after the pinch. It's a spare engine.
 
oye, a mishap in the pinching process. I'd imagine that'd put a bit of stress on the rest of the parts, no?

curious to learn who pinched it for ya.
 
REVOTMAXX.18TM said:
I heated my OS .18TM to 145 with a hair dryer, try heating head only not the crankcase?????
Click to expand...

You want to heat the crankcase because it's the sleeve/piston you want to preheat.



IMO I think you need to send it bad to the person that did the pinch so they can relieve it, sounds better than fighting it for who knows how long.

Good luck with it!
 
Bustedgears- No, the rod is fine. It gets stuck at the exact same place everytime. I can tell by my "BDC mark" on my flywheel. Plus when I manually turn it over (with a crecent wrench around the flywheel.. yeah, I know... :shrug:) it shows compression is both direction.

Robmob- 10 minutes... wow. I bet I was only giving it like 2 minutes. I'll set my standards a bit highter today If I have time to try.

Revotmaxx.18tm- I think you might have that backwards bud. It's important to heat the crankcase, not the head. Heated the heat is virtually useless, you gotta get the heat in the sleeve... which is directly inside the block.

rccars411- maybe they overcompensated.. it was really loose when I sent it in. Also, I'm not ready to throw anybody under the bus quite yet. I'll give it a more thorough heat the next time I try and see what happens. However, relieving info was given in the above posts.


smaxxin- If I can't get it started with 10 minutes on the hair dryer it's definately goin back. I'm not gonna start doin all sorts of crazy out of the ordinary things to get this thing running. First off, starting an engine shouldn't be this difficult, freshly pinched or not. Secondly, I simply don't have time to spend dickin around with it. I'm lucky to find 30 minutes here and there just to heat cycle it.
 
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My latest two mills have been Nova's, a P5X and a 528XR. I use an actual heat gun and then just let it turn over on the box for a while. A heat gun will get you temps of 200+ which is close to normal operating temp.
 
it was rainy and just generally ugly out today so I didn't try. If the hair dryer doesn't get it hot enough I can borrow a real heat gun from work.
 
Well, this is still a no go. Hair dryer creates sufficient temperatures but it's keeps getting stuck. I'm done as of right now (baby woke up). I took the head shim out when I came in, I'll try it again later when my wife gets home. If it still won't start I'm sending it back in.
 
Taking the shim out will give you more compression. How hot did your hair dryer get it to? Did you try just letting it turn over with no glowplug and a warm block?
 
jetmechG550 said:
Taking the shim out will give you more compression. How hot did your hair dryer get it to? Did you try just letting it turn over with no glowplug and a warm block?
Click to expand...

right, right... duh. heh. Plug saw 170ish, the side of the block where the heater was directed saw 200. No, I didn't try taking the plug completely out but I did loosen it quite a bit. I truly don't believe it's NOTa compression issue. I believe it comes down to friction. It's just too tight. I have to use a channel wrench to get it unstuck. I'm not even gonna bother later on. I already sent OSRocket an email letting him know I'm sending it back tomorrow. Hopefully, he can relieve some of that pinch.
 
I missed the OS Rocket part, I've seen others state that he over pinches once in a while. He should be good for it though as far as relieving it.
 
jetmechG550 said:
I missed the OS Rocket part.
Click to expand...

I never mentioned it before... didn't want to throw him under the bus before I gave it a thorough try. yeah, I've read that he's good for fixing them as well.
 
I have never sent any in for pinching, but one would think they would at least check to make sure they didn't over do it. Simple measurement with calipers should do it. But what do I know.
 

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