Nitro engine maintenance & disassembly

[Dr. Robotnik]

Hi guys,

How do you take the crank shaft and piston out of a nitro engine? I have the piston sleeve out and everything else is disassembled but...

Cheers

Ed

[Halgar]

I found that smacking the curb just right does a fine job of removing parts.

Sorry, I've never tore down a nitro that far. when Maxx would toast an engine, it was time for a replacement, not a rebuild.

[GAMMACRUSH]

youtube.com is awesome for tutorials... i typed in nitro engine rebuild and got a couple of videos, here is one that is helpful, there are more!

http://youtube.com/watch?v=dP6l3Pmt0Bw&feature=related

http://youtube.com/watch?v=yZpItkhrReQ&feature=related

[Dr. Robotnik]

Perfect. Top marks Gamma. I haven't been able to take my end plate off and had begun to think it was one piece. According to this tutorial it's not so that's my problem...

BTW I will be taking those pics for you tonight. I would have done it sooner but I have been very ill.

[Eau Rouge]

Hi guys,

How do you take the crank shaft and piston out of a nitro engine? I have the piston sleeve out and everything else is disassembled but...

With the sleeve out and the case back plate off, you should be able to remove the rod and piston from the crank wrist pin by pulling it off the crank pin at BDC. From there, the crank can now slide out the back side of the engine case. It might need a bit of a tap from the clutch shaft end to coerce it out. It looks complicated, but it's a pretty simple movement of pieces.

Getting the case bearings out is a different story.

[klavy69]

Yep, Just like Eau Rouge said above. Its pretty easy stuff once you've done it a couple times. The most important part in the whole shebang IMHO is in the reassembly. Make sure you put the connecting rod back on with the 'oil hole' on the bottom facing towards the carb. Experience speaks here.
Todd

[Dr. Robotnik]

Thanks again guys.

This is my first nitro engine and I have no instructions and have never seen one come apart. So when I disassembled everything and the back plate wouldn't come off. I began to assume it was all one piece, but with that tutorial video and your comments I know once I manage to remove it I'll be able to see the connecting rod and other parts. It should then be easy to disassemble from there onwards.

Thanks

[uzzi]

remove the rod and piston from the crank wrist pin by pulling it off the crank pin at BDC.

BDC? don't you mean TDC? at BDC the rod would be in the groove in the crank case.

To remove the backplate try twisting the the backplate and exposing the corners. Once there, you should be able to lift the backplate off by holding the corners. Heat the crankcase if it still does not budge.

Do not use any use silicone based lubricants on the internal of the engine...to lube use light oil. Use extreme care when dealing with the sleeve and piston as a scratch will render it useless. When reassembling, ensure that no dirt gets into the engine.

Hope this helps!

[Eau Rouge]

remove the rod and piston from the crank wrist pin by pulling it off the crank pin at BDC.

BDC? don't you mean TDC? at BDC the rod would be in the groove in the crank case.

Nope, the only way to get enough flex and movement in the piston/rod is to pull it out from BDC or close to it. If the piston and crank are in the top-most position, there isn't enough room to even move the rod around let alone get to it. Plus, not all engine case bottoms are grooved for rod clearance (i.e. long strokes).

[uzzi]

He does have the sleeve removed already...so there should be plenty of room.

[Dr. Robotnik]

BDC, TDC it's all a moot point as I can't get the plate off, it doesn't twist, or move in anyway...I'll have to wait for my girlfriend to visit and then nick her hair dryer when she is not looking to heat this bad boy up....

[uzzi]

What you can do at this point is to place the backplate section into a vise (backplate facing the ground). Tighten it to a point where it just holds in the vise...do not squeeze it any further. You have to be careful as there is not alot of 'meat' for the vise to hold on to. Try twisting it off then...if you need more leverage...bolt the head back on. If it still will not budge....tap it slightly with a mallet. Use a rag to protect the engine components.

[markt311]

soak the whole motor in old nitro or alchohol to help loosen stuck parts, tdc or bdc isn't so much important. you'll get the feel of it

[badhoopty]

Hi guys,

How do you take the crank shaft and piston out of a nitro engine? I have the piston sleeve out and everything else is disassembled but...

Cheers

Ed

dude, take a pic.


with the sleeve out you should have no problem getting the rod off the crankshaft once the plate is removed. at least on the engines i have. did you try rotating the crank slowly while trying to get the rod off?

[GJW]

ed try putting the whole crankcase minus the carb if it has plastic parts in the oven at around 100 degrees for 5 minutes.. wearing gloves remove it and try twisting that end plate it should move just be gentle this cast stuff is fairly fragile if the wrong pressures are applied in aggression trust me, you can also bang the main large bearing out on some soft timber when the crankcase is hot then access to the front bearing is achieved also,, if they need replacing... the rod can be removed from the crank with a long thin cable tie wrapped around it i put some material in the opening tucked in combustion chamber if the rod is really tight like on new motors, just take ya time.. re-assemble with synthetic oil i use mobile 1 and keep all parts very clean.. good luck brother