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PostPosted: Thu Apr 30, 2009 12:10 am
by peter
Hi Guys...I've had an interesting couple of days trouble shooting the motors....Glen, I switched the tiny tacks, but no change in the readings...still get 6000 easy on the rt. engine, and 5500 maybe 5600 on the left....checked throttle full open, thanks Tyler....However as I was retuning the rt engine, and it would excelerate great and idle great, it wouldn't run steady up around 5000 rpm.....just sort of surging, not much, but you could hear it.....this is not right, I'm not going to fly with that engine like that, so I took the carb off and to my small engine man, and after a new diaphram kit, ( the old one turned out to be in poor shape), and adjusting the was not in the level,...and blowing out the jets etc., I've got a motor that runs a heck of a lot better....although the left engine seemed ok I had him do it I have the peace of mind of knowing the status of both the carbs.....anyway, they're back on the plane, and idleing around 1800....thanks again for straightening me out on that low speed setting.... and ready to go.
Don...the tiny tack picks up the impulse fromthe extra magnets, and that makes it count double the actual rpm, although once it gets past 10000, it doesn't seem to be consistant.....the left engine seems to pick up a extra 100 or so rpm on electronic, but I don't see much difference in speed on the rt. one....All in all I think I'm going to be happy with my arrangement
Thanks to all for your thoughts and suggestions

PostPosted: Fri May 01, 2009 8:02 am
by Shannon
Hi Pete,

My advice is to continue working on the poor running engine to see if you can get it operating to an acceptable level. Having one exceptional running engine and one poor running engine really really bites. I personally would not be happy at all with a 5500-5600rpm running engine and would not fly it. Personally I don't think "running good enough" is something we can't apply to our 185s because we are underpowered from very the start.

My next step would be to get new rings, head, and base gasket for the engine and change them out. During rountine ring change I lightly (I mean lightly) run a smooth stone 3-leg hone in the cylinder briefly. I then crosshatch with a "stone" hone before putting in new rings. Keep in mind opinions vary on the "best" approach here.

Being that you have no detailed history on the engine a simple ring change would be the logical next step. The good news is a ring change is an easy 30 minute job once you know what your doing.

I have an idea doing this may get the engine running up to par. If not then you move on to other things like crank bearings, wrist pin bearing, seals, ect.

PostPosted: Fri May 01, 2009 8:58 am
Does anyone know where I can buy head and cylinder gaskets and possibly rings for the 185. A phone number would be very much appreciated.

PostPosted: Fri May 01, 2009 9:12 am
by Shannon
Everything is readily available for the engines. Ask salesman for parts for a "Mark 3 portable fire pump" with Rotax engine at these locations. In Canada may be better to contact Bob Robertson (I think that's the guy).

Need to know if your cylinders are standard or oversize bore so you can get the right rings. I usually order from GA or OR dealer. Be ready parts are very expensive.

Part Numbers:
915 240 Standard Rings
915 241 1st Bore Oversize
930 045 Head Gasket
230 068 Cylinder Base "Flange" Gasket

Old Part Numbers
R-327 Piston Rings Std. Bore, R-331-0 First Oversize
R-238 Head Gasket
R-235 Flange Gasket

United States
Walt Bladh
950 Riverside Parkway, Suite 50
West Sacramento, CA United States 95605
Tel: (916) 372-9004
Toll free: (800) 426-5207
Fax: (916) 372-9006

United States
Jack Makin
16311 NE Cameron boulevard
Portland, OR United States 97230
Tel: (503) 257-7900
Toll free: (800) 426-5207
Fax: (503) 257-7979

United States
C.J. Geiger
1070 Nine north Drive-Ste. 300
Alpharetta, GA United States 30004-2958
Tel: (678) 566-3473
Toll free: (800) 426-5207
Fax: (678) 566-3476

PostPosted: Fri May 01, 2009 9:44 am
by peter
Morning Shannon....the slow engine is a smoother sounding/running engine compared to the other...not so much pop or shake at idle speed....I've suspected that the timing is a bit slow, and that might account for the lower speed?....Here's something interesting,...I started the motor yest. and the idle stabilised about 1765, and while watching the tack, switched over to electronic and the speed increased to 3900, and then up around 4000....that's an increase of 200 rpm or wot the tack goes to 10000 and increases up to a reading of 800 or doesn't go over 1000 and the other engine doesn't either....It makes me wonder if the fast engine slows down on electronic, and in fact at idle speed does drop a little, and the slow one speeds up.....I guess the only sensible thing to do is take them both off, replace points and condensers, get the timing dead on, and do the rings least then I'll know for sure about that aspect of the engines
We've had a whack of rain here in sw Ontario and its going to be another week or so before my strip is dry enough to use...Hate to take the motors off again, but it's a good chance now to do it.....Anyone know of a good fast supplier of 185 parts in Ont.?....or is Wildfire the only source?....Like to get at this.
Thanks once again....Pete

PostPosted: Fri May 01, 2009 9:56 am
by peter
Thanks Shannon...Just read your post for parts....Looks like Bob Robertson is my man....Appreciate it.....Pete.....I think I've seen Shorty recommend him

PostPosted: Fri May 01, 2009 11:27 am
by Shannon
Pete I don't think you can go wrong with a comprehensive approach to fixing the engines. You have already gone through the carbs so you are pretty much assured everything is correct with them. If your adjustments are in-line with the manual procedures then you know that you are in the proper range for good results.

The ignitions also need to be worked over and dialed in to assure that they are not a source of problems. New points and condensers are a great idea. It's just better to get rid of all of that old stuff and start fresh. It is imperative that the ignition timing be tuned with a multi-meter and top dead center gauge. There is absolutely no way to get wanted results when setting the timing using "ball park" feeler gauge methods. Any good two stroke mechanic should have no trouble setting the timing up very precisely BTDC using the TDC-Meter method. The needed TDC gauge needs to be equipped with an 18mm adapter for our engines. Most TDC gauges are sold with 14mm adapters.

For now I would disregard any readings you get with Electronic ignition. I would strictly use the readings you are getting on points-condenser for tuning and evaluation. The point ignition is the "control" for your experiment. First get the engines running with "known" values of point ignition. We already know how the engines are supposed to run with points.

It may be a bit of struggle and expense to get the motors running correctly. Historically speaking the failure of an individual to understand and master the engines will dictate the quickness of failure with his Lazair flying endeavour. In the long run it's cheaper to do what it takes to get the engines running correctly.

As a footnote I've seen guys who initially knew very little about engines build up the knowledge and confidence to completely master the 185s inside and out. One guy that comes to mind by his own admition had never touched an engine with a wrench. He went on to learn with my help complete carb rebuilding, top-end overhaul, and eventually "complete" overhaul (bearings, seals, ect). He was really impressed at what he learned to do and how his engines eventually ran.

PostPosted: Fri May 01, 2009 1:14 pm
by gdewsbury
I called Bob Robertson a week or 2 ago. He has some parts left but indicated that he was not going to continue supplying parts once stock is gone. He indicated that because of a lack of business for the 185s he had to let go the man that was doing the rebuilds.

Is there any one else in Canada to get parts from?
I need one lower piston ring and Wildfire will not sell with out complete piston.

PostPosted: Fri May 01, 2009 1:55 pm
by Shannon
Glen did you contact a Canadian or American location of Wildfire ?

PostPosted: Fri May 01, 2009 4:39 pm
by gdewsbury
Canadian Wildfire