moespeeds

moespeeds

Well Known Member
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I've got a small leak that's coating my windshield over about 1.5 hours of flight. I have determined it's engine oil, as it was clear right after an oil change, then got darker as I put more time on it.

It crept up as I was breaking in 4 new cylinders, running hard and varying RPMs. I can't seem to find the root cause though. It is coming from somewhere far forward, as it's all over the front lip of my cowl, right behind the spinner.

We installed this new WW 300RV prop in Jan, and since have put about 70 hours on it. I just noticed this very annoying leak in the last 8 hours.

What's baffling me is everything up there is dry.

Crank nose seal - dry
Back of spinner - dry
Prop blades - dry
Ring gear - dry
Rear of prop hub - dry
Front cowl vertical surface - wet
Case top mating surface - leaking since I got the plane (200 hrs)
Oil pan gasket - leaking since I got the plane (200 hrs)
Possible small leak at the base of #1 cylinder (there was a nick here in the case we noticed during cylinder install)

Pulling the spinner tonight to inspect the hub.

-Don't judge my sloppy RTV job, it was a rush job to get the plane in the air the next morning!
-The #2 fuel line leak has been fixed.
 

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I know you said it’s oil, but it sure looks like grease from the Whirlwind prop hub to me. Mine was spitting grease several years ago and it had the same look and dispersal pattern.
 
I'm confident it's engine oil, as the tint matches my oil perfectly. Started out clear, and got darker as the week progressed (put 12 hours on in the last 7 days breaking in cylinders).

My old prop, WW200 was spitting grease after overhaul. I agree the pattern looked the same. I was sure this was the issue until it got darker.
 
moespeeds said:
-Don't judge my sloppy RTV job, it was a rush job to get the plane in the air the next morning!.
Click to expand...

Everything is relative, just look at mine and you'll feel great about yours again :D:D Some of us just want to fly. I'm cleaning it up a little today though.
 

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Front baffle is for sure leaning forward. No cooling issues though. Would this cause the leak? It's been that way for about 100 hours with no issues.
 
You'd be amazed at the way air churns around in there. It's not out of the question that it's coming from your leaky sump gasket and blowing forward and up to the spinner area.
 
I'll change the orientation there, but it's been that way for a long time with no issues. No harm in changing it though, and it looks like it's supposed to lean back anyway.
 
Turns out my front baffle does lean backwards like it's supposed to. It was just popped forward in that Pic.

So I pulled the spinner and there were big globs of grease near where each blade exited. Also had grease all over the big C clips that hold it all together. Called Whirlwind and was told that if it continued, I'd have to send it in to be resealed. Ironically, I had to send my WW 200 RV back for exactly the same thing after an overhaul.

So it looks like it is prop grease. I'm going to try to put more time on it next week before it goes in the shop for a G3X install in 2 weeks.
 
I’ve had 2 WW300 props that leaked since new. Both have been back to California for a re-seal. One continues to spray oil all over everything and the other is sitting on a plane that’s been out of service so I haven’t checked that one to see if it still leaks after a rebuild.

I’d love to participate in a resolution, but I’m not willing to spend $300+ in shipping unless there’s some sort of plan to change *something* rather than continue to just try again with the same materials and processes.
 
I just finally solved a problem JUST like this, but with a hartzel on my 10. It started with the aeroshell 6 separating and leaking oil but that stopped (no longer had streaks on the prop blades) but still getting tiny drops on the windscreen. took a while to figure it out.

I had oil ONLY on the right face of the cowl ring behind the prop and then it migrated to the inner area of the cowl inlet then up to the top of the cowl and on to the windshield, hugging the area where the cowl flat area meets the half round area. Nothing on blades or spinner.

The key was finding very slight black streaks coming from the prop hub ring gear interface. They looked WAY TOO small to be the source. Don't trust that feeling

Pulled the prop and replaced the o ring and the problem is gone. I believe the o ring leak was VERY minor and only allowed oil to pass when under pressure. Therefore any oil that makes it out is quickly taken away under heavy centrifugal force and leaves very little trace behind.

The marks on your cowl look just like mine did. My streaks didn't make it to the bell shaped portion of the ring gear, but I can see the streaks on yours in the pic. It is apparent fro the pics that yours is a larger leak than mine was.

Yoiu have my # and are welcome to call to discuss further.

Larry
 
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Larry this describes my problem exactly. The oil was built up thickest on the 9-12 o'clock position of the cowl ring, when facing the airplane from the front. My hangar mate and I both noticed faint streaks on the ring gear, but it felt dry to the touch so we ruled them out as insignificant.

I did clean the gear up with avgas and I'll fly it some more to see if the streaks re-appear. I'll order some new O-Rings from WW this week.

Thanks again for helping me out, I'll give you a call later today.
 
WW now uses different grease

My 300-72 started to spit grease a little over a year ago. At that time they were resealing them in northern Ohio. (They still are but use an independent prop rebuilder) I took it in and they showed me the grease they were using (5 gallon bucket) with pockets of very thin oil laying on top. They now have switched to a new type of grease (I believe it is the same grease MT uses). I think what set off my grease separation was it sat in paint for 4 months and started throwing grease shortly after. So far the resealed prop has not shown any sign of grease spitting.
 
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