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O-290-G's

smutny

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So, I bought a house on an airpark and in the hangar are a collection of four O-290-G's, the ones from GPU's. They are in various states of conversion to aircraft use.

I wasn't interested in them so the guy I'm buying the property from wants to sell them. I do not have a price, but if anyone is interested, I can put you in touch with him.
 

Dave Baxter

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John I might be interested? Give me his name and number. Dave
 

Splinter

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John,

Can you send me more information? A price? What parts are there? Is he willing to sell some of it, or is it all or nothing?

Pm sent!

Thanks!
Nick
 
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Dave Baxter

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Nick about two weeks ago I asked him to give me some idea of what he wanted for the stuff, and he said make an offer! I told him I needed some idea as I did not want to insult him and he said he was busy helping his sister move and did not have time to research and get some idea as to what it might be worth, only saying that he wanted to sell it all together? I do not want to drive up or fly up to look at the stuff unless he has an idea of where to start price wise? The stuff has been setting for some time and is mostly O-290 G parts with one engine converted but has not been run for a very long time!

I have most of the parts for my O-290-D2 but still need cam lifters and some rocker arms! But the O-290 G has solid lifters and will not work in the -D2!

So if you can make a deal with him go for it? Dave
 

David Adam

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Back in the early 70's, when a guy could still build an IAC competitive Pitts in his garage, the GPU's were all the rage. I hope they get built and put on something cool! I'm trying to come up with all sorts of excuses why I shouldn't try to drag them home myself....
 

EAABipe40FF

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I can/could find MANY excuses why NOT to drag them home

I have a converted GPU in my Spezio. The ONLY parts that are GPU are the cases and solid lifters/rocker arms. It was rebuilt with a brand new O320 crank 150 hours ago, just to say I have some limited experience....

IMO unconverted O290 GPU's now days have a very limited value. Almost everything, cylinders, sump, acc. case and other aircraft related parts need to be replaced. O290 parts are far, very far from easy to find.... Indeed many/most owners of O290's find it cheaper(and better) to convert to a O320 when OH time comes...

So don't pay too much unless you alrerady have a ton of "aircraft" O290 parts on hand.



Jack
 
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EAABipe40FF

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One other note, and again just opinion:

While I wouldn't get a warm/fuzzy feeling using one for acrobatics, I don't think there is much of a real problem with the O290 GPU cranks. They are actually a O235 crank with it's thinner flange. And while there were several GPU crank flange failures, I suspect they were the result of using cut down metal props on Tailwinds, Mustang 2's etc.

If used with full length(72-74") 76AM6 O235 props which are on the TCDS for most O290 Pipers they(crank) will likely be good to go and the added plus is the 76AM6 props are relatively cheap.(Indeed I have one fresh OH for sale)

(even with the O320 crank, I'm using a 76AM6 series prop on my O290)

Jack
 
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David Adam

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I can/could find MANY excuses why NOT to drag them home...IMO unconverted O290 GPU's now days have a very limited value. Almost everything, cylinders, and other aircraft related parts need to be replaced.
Bummer Jack - You're bursting my bubble buddy. I am curious though, why do the cylinders need to be replaced? The first Pitts I flew had a GPU that had an O-235 sump, rear acc case and a PS-5 carb, but EVERYTHING else was right off the generator. It ran great, we loved it. Why do you say so many of the original GPU parts (other than lower sump and acc case) have to be replaced?
 

rhartmaier

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FYI to anyone who wants to use the GPU crank. It is correct that the only difference is the thinner flange. John Thorp hot-rodded many GPU engines. He recommended a stiffener plate behind the flange to beef it up. Check out the T-18 forum for more information, or PM me and I can provide a copy of the drawing. Bob
 

TFF1

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Without a o-320 crank I would not do aerobatics, but to yank a Tailwind around if you could get it cheap. If the engines were closer I would be interested. Shipping would be high half around the country. My plane had a GPU engine on it and it was a nice conversion. The front of the case should be stronger than a regular case. Parts are hard to find. I would love to do a ground up conversion but now it would be pretty costly
 

smutny

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Update - The owner of the engines has removed them from my hangar.

While helping him pack them up, I took a good look at the engines in the sunlight and the components that were boxed up. The stock crank does look quite light for aircraft use. Also the pistons were marked 6.5:1 and had flat tops as opposed to Lycoming's aviation pistons with a convex top with recesses for the valves.
 

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