need a good radial guy

[avbug]

Be careful what grease you use; don't mix greases, and don't overgrease.

Prop governor without a pilot valve? I haven't opened the propeller in question, but all the woodward (and other) governors I've dealt with that controlled ham standard props used a shaft and pilot valve.

The propeller uses counterweights, which is why I said check them...but the counterweights are there to balance against aerodynamic twisting force, the make it easier for oil to do it's job on the prop. That oil is routed by the govrnor, which uses flyweights moving a pilot valve against a speeder spring, which is in turn compressed by the pilot using the propeller control.

 

[svcta]

So for the update....

Here's where I am: I've got a low RPM limit (at barometric pressure as you described) of 1125. I was able to adjust the high RPM stop on the governor to achieve the 2250 with minor adjustments both there and at the throttle quadrant to assure proper clearance of hardware there. So that problem is fixed and I flew the airplane for about an hour today and it ran flawlessly again. What are your thoughts on the low RPM limit? Is that number acceptable in your opinion? The low RPM limit can only be manipulated by changing the geometry of the pushrods and control arms involved(there's not an adjustable stop on the governor), which will turn in to one of those day-long-in-and-out-of-the airplane-cranking-and-shutting-down over and over kind of jobs. What are your thoughts on the 1125 RPM that I've got?

Question for ERJ-145(or anyone else, of course): The covers over the counterweight bearings
or how to get to the covers off, really. There is a clevis pin with a cotter pin acting as a safety on the cover. When the cotter pin is removed the clevis pin just slides right out and then what? I grappled with that thing for a half an hour before deciding that it must not thread off the way I had assumed. They're knurled around the circumference so I assumed that they thread on/off. Both were impossible to move with what I consider to be 'reasonable' force. What's the trick to getting those covers off?


Thanks so much for all the advice so far, the steers have been dead on thus far.

Still looking for a good radial guy to keep in the rolodex in the southeast. Anyone have some names?

 

[avbug]

If I undersand correctly there are no power issues and there's no vibration, and your RPM has been recovered by the methods you described. Sounds like there's no more problem.

Low RPM limits sound find. I wouldn't mess with them. Sounds like it's riding on the high pitch stops, and that's all you can ask. Ballpark number at barometric ought to be about twelve hundred; your number is good. remember that the RPM gauge is generally wrong anyway...not much in the cockpit ever gives you more than aproximate information anyway. (Much as we'd all like to believe, anyway).

I'd leave the counterbalances alone. Lube and grease as required, but if you had a single balance weight issue, you'd have RPM fluctuations and vibration.

Are you seeing the performance you normally expect in flight, now?

 

[svcta]

Thanks for the opinion on that....leaving it alone at this point seemed like the best course of action to me, too. The numbers are back where they need to be and it's running great. In flight and off the ground it seems to be right where it should be, so I think we're done here.

Re: the counterweight bearings, the military Mx manual calls for grease after every flight. Therefore those covers I asked about must(one would think) be easy to remove(and they are supposed to be for proper distribution of the grease), but I can't seem to get them to budge. I'm just curious if there's something that I don't know about them. I was able to get grease in through the slots in the back side of the assembly, but it says to do it from the other side.

 

[bell47]

another prop trick..... we used to turn the prop verticle and pour STP oil treatment around base of the blade where it goes into the hub. leave overnight and it will run all the way through. You need to wipe off the excess( a rag with av gas works well) , then grease your hub and weights. As the STP goes through the hub it really seems to flush out dirt and other stuff in there. Be sure to place a drip pan under the bottom blade! Seems to make it really smooth.

 

[avbug]

What this generally does is lube the outside of the doughnut seals...doesn't go right through the hub. Some operators use motor oil too, and the main function is to slightly swell the seals to help prevent leakage. We used to do it on an Ag Cat, too. However, I'm not convinced it actually does anything.

If it's going through your hub, you have serious problems.

Were you meaning to say it flowed through a spinner, instead?

 

[bell47]

Avbug, No I meant hub. When you pour the STP down the top blade it will run through the hub and leake through to the bottom blade. Now I'm not sure what it does or where it goes in the hub but it seems to lube it nicely and tends to flush out dust particles. I assume we're talking the same prop, I'm talking about the counterweighted props that you have to grease the counter weights and hub. I've done this on probably 5-7 different props over the years and they all dribble through. Also helps during run up to cycle prop a bunch after doing this and the clean the windshield before you fly it, as the STP really slings everywhere.

 

[bugchaser]

I have also seen the STP trick done in the past. I too am not sure about the results. One thing for sure is that is will make a mess all over the airplane. We also had a wooden prop "wrench" that fit over the blade so that one could twist the prop back and forth. We would do this after greasing on particularly sticky props. You mentioned something about getting the covers off to apply grease. Do you not have any grease fittings? There is also a product that clamps over the prop blades and supposedly forces grease into the hub. I think that is was called a King greaser or something like that. Again, the only result I ever saw from that was a big mess all over the airplane. On a side note, do you guys run the engine up prior to shutdown and pull the prop back. This protects the prop cylinder as well as having the prop control in the proper position for starting a counterweight prop. Of course all of this could be avoided with the installation of a hydromatic propeller.

 

[Frozen Ronin]

Wow, be careful loading up a hub with STP or MM oil. It acts as a great cleaner and lubricant, but will continue to clean even after you re-grease the hub if it doesn't all get out. That leaves you with rapidly spinning parts without proper lubrication.

We use the 1340 on the single Otter, not sure if the prop set up is the same. Doubtful. But I haven't seen sticking issues in service up here.

So much to learn!

As far as a great Radial guy in GA, have you checked with any of the Yak or CJ guys? There are several in Atlanta (Delta guys), and they might have a lead on a round motor mechanic.

Love to help you, but the run to AK might be a little expensive!

Ronin