And to state the obvious.....confirm you have an accurate oil pressure gage before changing relief valve tension. I had to buff the plunger a couple of times on my 1/2 VW when OP got a bit erratic. Cold oil can also impact pressure.
And to state the obvious.....confirm you have an accurate oil pressure gage before changing relief valve tension. I had to buff the plunger a couple of times on my 1/2 VW when OP got a bit erratic. Cold oil can also impact pressure.
My worst case came on a ~35 degree day. The headrest of my airplane is a half-circle of plywood, fitting on the end of a truncated cone, covered with vinyl.
The guy who built the plane made the plywood slightly larger diameter than the metal bits. When I was sliding down into the cockpit, the edge of the plywood, under the vinyl cover, acted like a hook. It grabbed my leather jacket, it grabbed my sweater, it grabbed my shirt.
Which meant I sat down with my bare back pressed against the frozen seatback. Yeouch!
Ron "Bareback mountain" Wanttaja
How about using oil with lower viscosity during could winter period ?
It was the same problem in the heat of summer, so it's not a function of oil weight.
The opinions and statements of this poster are largely based on facts and portray a possible version of the actual events.
Don't need the scarf with a turtleneck either...but like you say, one HAS to wear a scarf.
My wife even found me a replica WWII RAF scarf, dark blue, with white dots. That's what I normally wear.
http://www.bowersflybaby.com/stories/scarves.html
Ron Wanttaja
My Mom knitted me a new scarf that is twice as wide as the one she originally made, as the thinner one won't stay up to cover my lower face.
I drove down to Birmingham and picked up new oil pressure relief valves. The pressure is still way too high, and I'm going to have to cut down the rear spring some more to allow the stopper/piston to relieve some of it.
The concern, of course, is that I wind up taking a bit too much off of the springs, and so I needed a fresh set in case I have to start over.
The rear piston thingie looks like it's the wrong one, having a set of small grooves around it horizontally. They're perfectly spaced and go all the way around, which hints that it's the wrong one for this engine. The one for the single oil pressure relief engines is made like that.
I worked some fine grit sandpaper in the tube that holds the relief valve, and didn't feel any roughness in it.
So tomorrow it's up to the airfield to once again drain the oil,* pull the oil cooler off, and go through the whole adjustment process again.
My goal is to replicate the normal oil pressure operating range of 10 pounds per 1,000 RPM, as the hot rod springs in favor are designed for high RPM's and temps. At a max RPM of 3300 and a cruise of 2500, I'm not really taxing it. Indeed, I've yet to bring the oil up to operating temperature range in flight, even with blocking off the oil cooler to just a small window. And yes, the sensor and gauge are working, as when I was adjusting timing without the prop it heated up just fine.
The joys of running a VW have me singing its praises today. Cost of two new oil pressure relief valves and springs? Five dollars and forty five cents. And the oil is bog standard 20-50 and five quarts can be had for the price of one quart of aviation oil.
* I'm pleased to report that the oil, after running two hours in the newly rebuilt engine, came out looking pretty darned good and metal free.
The opinions and statements of this poster are largely based on facts and portray a possible version of the actual events.
The ongoing saga:
With the improving weather, scarves and the like are proving to be nothing more than fashion accessories (knock on wood, it's still January). Springs cut, replaced, and I took her up and around the patch, leather coat, flying helmet, goggles, but no mittens and no scarf (though I did have long johns under my pants). I was comfortable the whole time.
It boggles my mind that one can't find NOS oil pressure relief springs for a Type I Bug engine, and that all that is available is after market "improved" ones that have too much tension for low RPM/low temperature use. If I could find a "pull a part" junkyard with some bugs in it I'd be crawling underneath with a screwdriver and a hammer.
Went up the day before yesterday and it was much improved. At full RPM's (around 3300) I got a little oil out of the spinner, but I'm okay with that, as it's at the full 3+ quarts (there's a about a pint or so in the oil cooler and hoses to it). Oil pressure at cruise (2500 RPM) was 40, and after an hour, on landing, it was 20 at idle. Roughly twice what it really should be, but it won't hurt anything. I may just have to keep the oil halfway or a quarter above the add line on the dipstick.*
I double checked that the venting for the engine case was clear, and it is, so no over pressure there.
A little oil on the cowl and a few drips on the bottom of the upper wing, the right wing, and right elevator, but none on the left. Easily wiped off and not a problem. The decision to use exterior house paint on the plane has really paid huge dividends.
I also learned that when a handheld radio battery gets low it will continue to receive loud and clear but won't transmit. The TX light is a lie. Having the spare battery thingie that can take six AA batteries saved me a lot of troubleshooting, as - fortunately - it was the first thing I checked. ICOM makes a fine product, but why they omitted a feature to show battery charge level is beyond me. Yes, it does have a little icon that will show up SECONDS BEFORE THE BATTERY IS COMPLETELY DEAD, but that's not exactly helpful.
It sure was nice to fly for half and hour the other day. Pretty bumpy, owing to the front having moved through and the sunshine heating everything up (Wednesday = freezing and snow, Sunday = 65 and sunny), but getting pushed around is just a function of what the airplane is. I had to keep the flight short as I had around an hour in the tank (three or so gallons) and am a bit skiddish about pushing the minimums - and both my Jerry cans were empty, so no filling her up beforehand.
I improved the engine baffling, making up some strips of leather folded over flexible cardboard and putting them along where the aluminum sheet projects to the cowl. It seems to work just fine. There's some spots along the firewall where the cowl doesn't quite sit flush against it that I'm going to mark up and fabricate some sort of soft blocking of it. It may be as simple as some duck tape folded part way over itself and attached to the firewall.
Culver is cutting me a new propeller, as the one the sent me was 60x27 instead of 62x27. It doesn't really matter - I don't think that extra inch of length on both ends will really improve anything - but when I mentioned it to them they immediately said they'd cut a new one for me and send me a shipping label for the current one when it's done. Now that's customer service! It'll be interesting to see what finish Alaina up there will put on it (I just leave it up to her with the instruction to "make it pretty.").
Next up is improving the combing around the cockpit and adjusting the gun. I did the combing in the most get-it-done manner I could, slapping some scrap faux leather over a bit of garden hose and pipe insulation and wrapping over with a long boot lace to keep it in place. It looks way better than it should, but it's not really as secure as I'd like it. So I procured some leather from a recliner someone was throwing out (they put it on the curb for the trash man and in short order the back panel of it was cut away - always, always carry a knife!), and it has a nice section on the bottom with the pile part of velcro where it attached to the bottom of the chair. That section will be used for the very rear of the cockpit, and I have industrial velcro that will hold it in place across the back.
So I'll remove what I have and either recycle it if I can, putting some eyelets in it and lacing it properly around the edge with some leather strap (okay, leather boot laces), or just make new, as I think I have enough.
My gun is too far forward and set at an angle to where the convergence would be about 15 feet in front of the prop. The latter would be funny if it didn't actually bother me, and the former is a matter of aesthetics. It just doesn't look right. I'm also hoping that moving the gun back four inches will make it more stable and I can use it as a viable camera mount. As it is now it vibrates just enough to make the camera work suspect and needing serious editing to make it worth showing.
* Checking the oil level isn't as straight forward as one would like. I have to lift the tail to bring the oil pan level, wait a little, and then check it. Since the dipstick is at the very forward edge of the engine (and thus at the high point), I don't trust whether or not there's a little daub of oil on the tip and call it good.
The opinions and statements of this poster are largely based on facts and portray a possible version of the actual events.
Last edited by Sam Buchanan; 01-23-2018 at 06:29 PM.