New to me..

[docfoley]

First of all, thank you to everyone for helping me. Second, this site is a great treasure trove of information!
I took this last week off and and wednesday and thursday I spent the day in the shop at Twitchell's doing a pre buy which went fine. Yesterday I sealed the deal and she's mine!

[c170b53]

Although we think we know everything here about 170's, don't be afraid to put us to the test. Should you have questions about your new machine, looking up fellow members in the directory that live nearby your field is another way to fast track the familiarization phase of aircraft ownership and a quick way to get into club participation.
Ah...who am I trying to fool ...we are desperate for new member posts! .....
Btw, a nice traditional looking plane with modern paint scheme. Welcome to the club!

[docfoley]

Thank you. The paint is quite good and it has a new Airtex red and grey interior. It has the original panel in it but the DG and HSI are not currently functional as there is no vacuum system at the moment. I'll fix that soon.

It flies straight and true and the engine is very smooth. 20" of manifold pressure give a cruise speed of 120 mph.
This is going to be a lot of fun

Charley

[bigrenna]

delete

[Bill Hart]

Nice looking airplane, how about a photo of the panel.
Welcome to the club.

[docfoley]

Some more pictures. Note that the DG and HSI are non functional. The T&B is a bit off and deflects a bit to the right. I haven't decided what to do about them yet. The panel photo was taken when I was flying it back for the pre buy inspection. I have already committed blasphemy and replaced the mixture control with a new mixture control where the cigarette lighter was so I didn't have to drill any holes.

[johneeb]

Charlie,
Do a search here for information about disconnecting the parking brake (a really good idea). I making an assumption that yours is still connected as I can see the springs in your last picture.

[GAHorn]

Charlie, what engine has it got..??? and why doesn't it have a vacuum system...???
(Has it been converted to a O-300-D? and not have an operatonal vac pump? What happened to the venturi system?)
(I've got two, excellent condition original venturiis that'll get that system operational for you.)

[docfoley]

I got rid of the parking brake during the annual

The engine is a C145 H2.
It had an airborne vacuum pump on it a very long time ago but that has been removed. When the pump was put on they pulled the venturi's. I have the venturi's. I need to strip and paint them. I will be reinstalling them this spring after I clean and paint them. It's a high priority item for me.

I'm on the fence about getting the original DI and HSI rebuilt and using them or putting in more recent instruments. I understand there is an issue with modern instruments needing a little more vacuum but some people are using them with original venturis successfully. I really don't like the panel location of either of the originals but at the same time I really like the general appearance of the original panel....

[Bruce Fenstermacher]

Charley might I highly suggest, since your going to be doing the work that you might want to substitute a 8" or 9" inch venturi for one of the stock ones. Of course you will need a regulator with it but you probably have one if your reinstalling the dual venturi setup.

[Bruce Fenstermacher]

Also Charley might your aircraft records still contain the installation instructions for that Airborne pump. We'd love to have a copy of them for our library and we also have a member recently looking for the same.

[docfoley]

I can go to the nines. I have the regulator from the airborne but not the other parts. I did not see the installation instructions, only the 337.

[Bruce Fenstermacher]

Darn it thought I might have found some paperwork.

I'd put one 8" on and if I needed it then I'd get a second or I'd even try it with a 4". The 8" and 4" will be a slightly different length and shape only noticable by most when they are next to each other. To bad these 4" venturi aren't worth anything, seems everybody has a few in their hanger.

[docfoley]

Of note, my venturis were mounted on opposite sides of the aircraft and were never mounted together.

[GAHorn]

Darn it thought I might have found some paperwork.

I'd put one 8" on and if I needed it then I'd get a second or I'd even try it with a 4". The 8" and 4" will be a slightly different length and shape only noticable by most when they are next to each other. To bad these 4" venturi aren't worth anything, seems everybody has a few in their hanger.

Did I miss something? How did a mis-matched set of venturiis get into the discussion?
I believe a mis-matched set will only diminish the performance of the pair, neither achieving their potential.
I'm concerned the more powerful venturi will likely "backwash" the smaller, and will see the smaller as a "leak" in the system.

Cessna had dual, identical venturiis connected in "parallel" for their instrument airplane kit, to drive an AN DG, and and AN Horizon.
Here's how they did it:

To see a larger version, and other details, click on the #2 link below.

If a search is made in these forums, in two seperate threads, I talked about "upgrading" my panel to the "super" venturiis, because I wanted to assure plenty of vacuum existed for an additional (modern) 3-1/8" pictorial gyro.
1. http://www.cessna170.org/forums/viewtop ... on+project
2. http://www.cessna170.org/forums/viewtop ... +venturiis
Prior to the mod, my dual, standard venturiis produced about 4" of vacuum at 7500' MSL cruise. Lower altitudes produced a bit more, up to 5".
After swapping them out to super-venturiis, adding a third gyro (the new horizon) and an interconnecting manifold, and regulator, I see 4.5" at all atlitudes from S.L. to 7500', presumeably due to the added regulator. (I've not tried it above that yet.)
I'm certain that dual super-venturiis will prove satisfactory with whatever two gyros you have installed, and that's what I"d recommend.

Charley, I suspect Cessna put them both on the starboard side for a reason. There have been operators who noted reduced efficiency with those mounted on the port side. (Prop-swirl effects perhaps ??) Anyway, I've had excellent service from my right-side venturiis, and absolutely refuse to consider downgrading to a vacuum pump. (That should re-liven this discusson.)