Engine Question !!!!!!!!!!
 

Hi,

Hope someone can give me insite to this question !!!!!!!!

Im buliding a SuperSportstar 40 ive just added a new OS46LA engine into it, but my question is concerning this as its a brand new engine, when ive connected the spinner and prop when i turn the engine without a glow plug in, it makes like a clicking noise, a click each turn, seems to be comming from the washer (thrust washer area), as it happens when you push the spinner towards the engine aswell, its kinda like a click as it seems thiers a bit of a gap thier. The spinner and washer and nut have been done up tight but the cranckshaft moves just a little in and out which i think is causing this noise.... it seems to have a small bit of play in it......

Is this normal ? as i wanted to check this first before i atempted to start the engine....... and if its not what can i do to recitify this !!!!

Any help would be grateful, many thx

Engine Question !!!!!!!!!!
 

Pretty normal for it to have a touch of play there, but not too much. Go to the local club and get someone to help you start it and he can look and makes sure it is not excessive. It will also help you by having him teach you the correct way to break it in and check out the plane and help test fly and teach you to fly. If you try yourself, you will crash it.

Have a blast. Its a fun hobby.

Engine Question !!!!!!!!!!
 

the LA's tend to have more play (Shaft moves in and out) than the FX engines.

They will rattle at idle speed. So on this engine it is perfectly normal.

Engine Question !!!!!!!!!!
 

They rattle at any speed :p

Engine Question !!!!!!!!!!
 

I bought an slightly used 46LA on eBay a while back. Having heard so much negative about them, I really wondered if it would be worth the $40 I paid.

Well, I mounted it in my old, fairly abused Super Sortster Bipe, and have been quite impressed with the way it pulls the bipe around. :D Certainly not unlimited vertical or anything, but I think the 46 LA's are getting a bad rap.
Dennis-

Engine Question !!!!!!!!!!
 

That movement is normal with any engine that doesn't have ball races to locate the crankshaft, not just the LA. If it doesn't have any movement then something's wrong.

Engine Question !!!!!!!!!!
 

Just like the old FP's. People were always complaining about them, too. The 40 FP I had was a really good engine, it rattled, too.

Phil in MN

Engine Question !!!!!!!!!!
 

I have a couple of FPs and to me the are the old reliables. There is nothing wrong with bushing engines they just don't produce as much rpm .If you want a .40 size that produces more than 14,000 rpm with a 10/6 than look elsewhere. I think 2 strokes sometimes are judged by how they scream. the higher the Pitch the better.

Engine Question !!!!!!!!!!
 

I just had the exact same problem with my OS65LA... in fact there was so much play that the connecting rod was rubbing against the inside of the crankcase causing a very noticable clicking noise.

As the engine would attempt to fire the whole thing would just seize up and stop. I took off the back crank case cover plate and noticed that some actual gouges had been taken out of the inside of the crankcase as the engine attempted to fire.

To solve this, I replaced the crankcase cover plate and made sure it was on very tight which did limited the amount of play in the crankshaft... I will try and start it up tomorrow and see if that solves my problem.. if not I think I will send this back and get a replacement...

that play goes with the LA
 

This is hearsay because I have very little experience with the LA series of engines, but a club member told me a similar story about this kind of play. After a while, he couldn't get the engine to start with an electric starter, and could only start the engine by hand. I suppose it still worked.

Engine Question !!!!!!!!!!
 

It's possible for some bushing engines to have the crank rub the backplate. It's not good for the engine, but usually the prop pulling the crank forward prevents this from being a problem. However, because of this, you should go light on the electric starter, and never ever run a bushing engine in a pusher arrangement, it will eat the engine in no time flat.

Engine Question !!!!!!!!!!
 

I his last post, Montague reminded me of something when he said "go light on the electric starter."

The proper way to use an electric starter is to press the starter cone against the spinner and then hit the switch. :thumbup:

Never jam a running starter against the spinner. :thumbdown This is hard on any engine, but, especially a bushing engine like the LA.
I've also seen prop nuts spin loose that way.

Phil in MN :)

Engine Question !!!!!!!!!!
 

All modern bushed engines have a steel shim thrust washer fitted between the crankcase and the prop driver. Sometimes this gets lost or overlooked if the prop driver is removed and then the crankshaft can move further back than it should when the electric starter is used. This extra movement can make the crankpin contact the back plate.

Always be certain that this shim is lubricated before using an electric starter and never try to start a bushed engine without priming it first. At least then you've got some lubrication for the crankshaft.

Engine Question !!!!!!!!!!
 

Dr. Dave,
I have 3 40 FP's. Wonderful little engines that almost always start with one flip. (About the only engines I own that I flip before using a starter. :D ) I've moved up in size, so my FP's are just sitting right now. :(

Montague & Phil,
Thanks for once more pointing out proper starter use. I see so many at fields (and here) who are advocates of spinning up the starter, then slamming it against the prop. :rolleyes:
Dennis-

Engine Question !!!!!!!!!!
 

I see guys do that a lot, too, that's why I mentioned it above. In fact not too long ago I saw a guy do that and the prop spun right off the shaft without ever turning the engine over. :rolleyes: I looked kinda funny.

Phil in MN :cool: