Help identifying nitro engine

[chrisio]

Hi.
Can anyone help with identifying who makes this engine please. I need a new pull start for it. I bought a box of bits to make up a car and this engine was amongst the bits and pieces. Been assured its a runner and I don't want to condemn it for the sake of a pull start.

Googling the zx-21 brings up a whole host of random types of race engines etc none of which seem to look like this one.

Thanks in advance.
Chris

 

[ninnon]

It's got a black version of the cooling head off a Thunder tiger pro 21B Se:

 

[chrisio]

It's got a black version of the cooling head off a Thunder tiger pro 21B Se:

Cheers.

So do you reckon the pull start kit from that engine would work

Cheers
Chris

 

[olds97_lss]

Looks like there is more than one backplate for that engine too:

A lot of references to "Avioracing ZX-21". Most not in English.
Looks pretty old.

 

[chrisio]

Looks like there is more than one backplate for that engine too:

A lot of references to "Avioracing ZX-21". Most not in English.
Looks pretty old.

That's the one. its a different pull start to mine but its the same engine. If I can't get a pull start for that engine is there a generic pull start that will fit?

Specs of the back plate are
14mm one way bearing
28mm (ish) between the fixings.

Cheers for your help
Chris

 

[olds97_lss]

Wish I could help more. Would be nice if mfr's would list that kind of info on their parts, but they don't usually.

 

[chrisio]

Wish I could help more. Would be nice if mfr's would list that kind of info on their parts, but they don't usually.

I have spoke to a few model shops today and they are all saying the same thing basically there is nothing I can do! Looks like I will be binning the engine for the sake of a pull start.

 

[olds97_lss]

Considering it's age... might not be a bad thing.

 

[chrisio]

Ok.
The engine is an effective write off due to age and spares availability.
I am not willing to spend lots of cash on this project at this point in time so I don't want to buy a new engine but I have found one on Ebay (link below)
http://www.ebay.co.uk/itm/281909418053?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT

1st question - Is it an ok engine for the money (assuming its in a running condition)
2nd question - how do I remove the clutch/flywheel from my old engine - removing the clutch bell and shoes is easy but how do I remove the rest.

Thanks very much
Chris

 

[olds97_lss]

This in the description makes me a bit wary: Overall I think it's not been run in yet.?

Considering the anno worn off/falling off the head, the general cleanliness of the engine, the fading of the slide boot... it's clearly seen a bit of use. For $40, if it runs, it's probably worth it to you. A buddy of mine had one of those engines in my big block t-maxx 10'ish years ago. Wasn't a bad engine. Hot Bodies, powerhouse .26. I don't know the longevity of it as after I bashed with him for one season, he kind of lost interest and we never ran again. But the power output put my OS21RG to shame and it seemed to tune/hold a tune well.

To get the bell off, there's usually a screw or e-clip holding it on, then gently slide the clutch shoes off the pins with a finger on the back so the springs don't go flying. Then fold a paper towel up (if you care about the look of the flywheel) and grab the flywheel with channel lock pliers to hold it so you can remove the flywheel nut. Use a quality socket on the nut as they are usually pretty tight. Then put the tip of the crankshaft on a piece of wood and gently tap on the back of the flywheel to break it loose. There should be a cone shaped bushing (collet) behind the flywheel, be careful not to damage it. Usually the flywheel is held tight by the friction with the collet and a cone shaped recess in the back of the flywheel. As you tighten the nut, the collet grabs the crank and friction keeps things from spinning.

To put it back on, make sure the crank, collet and cone part of the flywheel are clean from oil, hold the flywheel with the channel locks again and tighten the nut. It should tighten/hold onto the crankshaft.

The photo of your engine looks like there's some sort of spacer behind the flywheel. It kind of looks like a pully that would spin something. I've never seen a flywheel like that before. I've also never seen a flywheel that far from the engine before... you may have a tough time getting the newer engine to line up with things properly, but I guess you will figure that out if/when you buy it.