shaunknee

Got a quick question for all of the DA-50 owners. I've run just about a liter of fuel through the motor now and there seems to be a little bit of play in the connecting rod. At the end of my 22" prop I can see maybe 1/100 of an inch movement back and forth. I can hear the play when I move the prop back and forth.

Anyone else ? Is this normal ?

Thanks

Shaun

DKjens

My Feedback: (50)

When was this engine purchased new? Desert Aircraft has come out with a crank upgrade, which the new DA50R engines all have now. I have been told, that the upgrade is different material or treatment of the crank, resulting in a more wear resistant crank. I have a friend locally, whose DA50R broke the connecting rod while running. Another friend locally had a DA50R that started getting so loose it had become quite noisy. Both engines were covered under the DA warranty. Basically, a tight gas 2-stroke engine will not make as much power as a loose one, so loose is good, to a certain degree. What I would do in your case, is find out where the nearest DA service is, find out if they have a new crank in stock. If they don't, when will they get, or ask the next DA service place. You are really in no big hurry to get the crank replaced, the engine will run a long time still, so try to time the down time to be the shortest and at a time where ou don't need the engine so much.
DKjens

H. Wayne S

My Feedback: (18)

Don't fly it !!! It will explode and kill someone!!!! AND you will loose your plane! Put it in a box and send it to me, I will properly dispose it for you. Go buy another one.

rmh

The DA50 -like all the engines of this size -type -- use a bearing at each end of the connecting rod -- not a bushing.
these bearings are -essentially, a little metal shell with small hardened pins packed all the way around the inside.
Ideally -the bearing -in the rod -- pushes easily onto the crankpin.
NO slop.
If you are stationed in Timbukto- and have to do your own repairs -make certain the crankpin is smooth with no small lines around it - also the at the assembly allows easy rotation but does not have even a hint of roughness or looseness when rotating the rod on the crankpin.
The .001 movement you mentioned - is about normal but I wonder how you measured it .
If the engine is dry and the prop is at TDC, you will feel looseness - which really is almost zero clearance.

JohnVH

My Feedback: (38)

Shaun, why dont you call DA and talk with them???

MustangFan

I had a problem with mine ... sent it to DA ... they promply changed the crank and bearings before they sent it back.
My problem turned out to be the electronic module. But they did the other work also.

I would sent it to DA !

I'm sure they will take care of it for you.

shaunknee

Thanks all for the prompt replies. Dave at DA wrote me back and indicated that some of the early DA-50's had a loose tolerance at the lower bearing. He said most were fine. He offered to fix it, but suggested I fly it a little longer. I think I'll fly it this summer and send it down in the fall. Just to clarify the problem, hot or cold there is a small "tick" when the prop is moved back and forth with the piston mid-stroke. Engine has only a 1/4 gallon through it. I wasn't sure if this was normal or not.

Thanks again for your responses !

Shaun