SR71 Engine Buying Advice

No... not that kind of engine.

I've been looking for a either a 401 or a 425 nailhead for a couple weeks now. I called a guy that had a pair of 425's with transmissions for 1 grand each. I called and got him down to $800 on one of them until he told me that one was seized. I told him I wasn't interested and he then told me he would sell me the other one for $800.

Then he proceeds to tell me that it has 750 some odd hours on the engine as it was used in a starter cart for aircraft. He then tells me that these engines were used in a starter cart to start the SR71 Blackbird.

Who knows if this is true... I asked for some sort of verification and he said he would work on getting some pictures of the cart he had laying around with one of the engines still in it. I looked on line and it appears that nailheads were used for this but they all say 401's were used.

Beyond the possible history I'm wondering if anyone knows if there are any differences in engine output when they are used for an industrial application or if they just grab one off the assembly line and use it for their needs.
If these truely came from the background he is explaining they didn't use any sort of exhaust on the engines... I'm assuming after 750 hours of run time that the valves and seats may see some damage. The engines have an original 4 bbl intake and carb and I believe they were rated at 340 or 360 hp.

Any input is welcome.

 

its true. 2 buicks side by side in the cart. There is a cart at the Warner Robins Museum of Aviation.They did have weed burner headers.

 

Yea... I know that was true but I'm not too sure weather or not the engine I am considering buying is one of the actual engines used.

And if it was one of them weather or not they were tuned differently than the same engine say in a car.

 

Sounds like a tall tail in MN, far from anywhere a sr-71 would have been based, but who knows...

http://www.sr-71.org/blackbird/startercart.php

http://www.v8buick.com/showthread.php?132028-How-to-start-a-SR-71-Blackbird-spy-plane

 

Tall tail indeed ... it would be kind of neat to boast having the fastest 36 coupe on the planet though.

 

Wait, why would a starter cart for a plane need a transmission? Or did he put the transmission on it?...

 

Be sure to get the cart! They were made by Kurtis Kraft, when they stopped making race cars.

 

Guy said the cart is gone "seized by the government" were his words.

 

Nothing different about them. And chances are the engine is going to need to be gone through regardless.

 

Someone on this board had purchased the whole set up and featured photo's of it while it was in use... they should be gone through however most of those engines are in perfect condition and just need an oil change, points, and fuel to get them running.

 

Cool... this is what I wanted to hear.

 

I was stationed at Beale AFB, home of the 9th Strategic Recon wing from 1986-92, in the pressure suit division, A local newspaper once mentioned that the SR-71 Blackbird was powered by 2 Buick V-8 engines. That got a lot of chuckles!

 

http://www.wvi.com/~sr71webmaster/ag330_sr.htm
http://www.flickr.com/photos/lajandy/5837986761/

 

He said the transmissions were used in the cart but it doesn't make sense to me either.

 

Just noticed in one of the articles that they did run automatic transmissions on the carts.... plus I see some articles list the engines as 425's and other articles as 401's.... weird...

 

The cart setup that I saw had a transmission.(maybe two) the engines sat 'normal', but the PTO to power the aircraft was upright (vertical) and had a telescoping shaft.The trans was connected to this 90* gearbox. This was at the USS Alabama museum in Mobile a few years back.
Why they used Buick engines.... I have no idea.

 

Ha, ha, ha, that newspaper had to have been the "Appeal Democrat".

 

The blackbirds were based in Nor cal. It doesn't get real cold there.

Even if it had weed burners on it there should't be any valve and seat damage. That said 750 hours in a real car would be somewhere in the neighborhood of 60K and that would not have been fired and run at full throttle imediatly the way a starter mill for an Aircraft would have been. So its not like you are buying a cherry just because it was a "stationary" mill.

Just something to chew on I am not trying to sour your deal for you.

800 is about core price maybe a little high core price, for one at least around here. So I wouldn't worry about it, if it runs for you and you got it for that price you have done well.

 

They have an AG330 start cart here in Utah at the Hill AFB museum, she's got a pair of 425's.
http://www.hill.af.mil/library/factsheets/factsheet.asp?id=5758

I doubt there is any way to tell if its really from a cart or not.

 

Using nailheads to start an SR-71.... that's a contrast in technology.

 

I think they were probably tow motors or it was some sort of a generator. I'm no expert on the subject but I don't think you start a jet engine like a piston engine.

Ya know its a little off topic but they dug the blackbirds out of moth balls not too long ago when they finally admitted that they existed to do some experimentation with new induction drives.

 

Not really, both were products of the 1950's, designed with slide rules. Kelly Johnson was a genius.

somebody correct me, but wasn't the Buick "putt-putt" used with most all AF aircraft?

 

My favorite description of the starting procedure...

The original start carts were Buick wildcat 401 cubic inch V-8 engines developing 400 horsepower. There were two Buick engines mounted tandem side by side with automatic transmissions. They were coupled together to drive a vertical shaft that was inserted into the starter mechanism on the bottom of the SR-71's engine. On engine launch there was one AG-330 Buick for each SR engine. For the first time observer of an SR-71 launch, the engine starts in themselves were almost indescribable. For one thing there was no mufflers on the Buick engines. As the Buick RPM was advanced, Flames almost three feet long erupted from the side of the start cart. It truly sounded like the beginning of the Indianapolis 500. Combine that sound with the steady increase of SR-71 RPM to engine TEB ignition at 3,200 RPM and then idle aircraft engine speed as the Blackbird comes to life. Then it all starts all over again with #1 engine. It never failed to thrill me to start the Blackbirds engines with the Start Carts.

I have heard that both 401's and 425's were used and in the mid 70's some changed to Chevy 454's

 

I'm no expert on this, but I know jet engines are normally strated electrically, either from an on-board or ground based APU generator. One of the previous posts mentions a shaft system.

 

....... and the guys who did the nailhead weren't?

 

The seller sound like a BS'er... doesn't tell you up front one of the motors is seized, says the cart was seized by the govt... this would be a "pics or it didn't happen" thing for me

 

Turbine engines are started by forced air.
The APU is a small turbine engine. I do not know, however, how an APU is started as E-2C Hawkeyes do not have APUs.

 

My understand is that after the stopped with the engines they went to a pneumatic starting system.

Lol, ijustlikefords beat me to it. I started the response about the same time and got distracted, ooohhhh shiney...

 

I already said I don't know much about this, but I do remember(not sure where) seeing jet engines that had electric starters. A quick search on the internet; it turns out that both pneumatic and electric starters are used. It depends on the engine.

 

The J58 was a variable cycle engine which functioned as both a turbojet and a fan-assisted ramjet. Bypass jet engines were rare at the time, but Ben Rich later described the engine as "bypass jet engine by air withdrawal".[4] At Mach 3.2, 80% of the engine's thrust came from the ramjet section, with the turbojet section providing 20%.[5] At lower speeds, the J58 operated as a pure turbojet.
The engine was started with an AG330 starter cart, with two Buick Wildcat V8 internal combustion engines with a common driveshaft. The cart spun the J58 to 3,200 rpm before the turbojet cycle could start. Later, a conventional pneumatic start cart was used.[citation needed]