Oil leaks

jbxx · Post by **jbxx** » Fri Dec 14, 2007 2:43 pm

Sort of off topic but when fueling the SR-71 with I belive it
was JP7 it would leak like a sieve<sp?>.
Was wierd fuel though, sort of gummy.
J.B.

Dicktater · Post by **Dicktater** » Fri Dec 14, 2007 2:58 pm

I have read it was due to the extreme pressure at alltitude,they built the SR71 Blackbird loose at ground level pressure, in flight it would tightin up and no longer leak due to extreme pressure in flight.

Lifer · Post by **Lifer** » Fri Dec 14, 2007 7:48 pm

Don't know where you read that, Dicktater. As altitude increases, air density (and air pressure) decreases. That being the case, any leaks would be all the more obvious and problematic at altitude.

M376X6 · Post by **M376X6** » Fri Dec 14, 2007 8:09 pm

Interesting detailed history on the development of the bird and the "Skunkworks". The plane is never completely fueled before takeoff because of the leaking. It must fueled in the air immediately after take off. Pilots must wear special suits because of the incredible heat that the plane generates. There is where the problem of leaking comes from. The story of the plane would take several pages. While on the ground and cool the fuel system leaks because of loose fittings etc, Once the plane reaches normal operating temperature, the system seals itself. Normal operating temperature is much too hot to touch. The skin is made from titanium and is designed to warp into correct surface angles when it reaches temp. Because of the annealing (heat treating)process that takes place with each flight, theoretically it gets stronger each flight. If I can remember the book I'll pass the title on to you folks. It was actually about the fellow who ran the Skunkworks for Lockheed back in the day. Fascinating book.

Regards,
Bryan Sage

jbxx · Post by **jbxx** » Sat Dec 15, 2007 6:56 am

I think that the book you are refering to is
"Lockheed Martin Skunk Works"
I forget the author.
Mostly about Clarence "Kelly" Johnson.
He was a terror to work for.
J.B.

Lifer · Post by **Lifer** » Sat Dec 15, 2007 7:21 am

Thanks, Bryan. That makes sense.

SOTVEN · Post by **SOTVEN** » Mon Dec 17, 2007 11:37 am

Hello everyone. Regarding leaks, everyone has a good point here. Definetely Charles speaks the voice of the truth. However, for the rest of us like Lifer who do not mind A SMALL leak over repairing effort and expense, I guess it is ok to run the trucks like that. Regarding age, I have seen new cars and trucks, quite expensive also, leaking various liquids within a couple of years from ownrship. The cure that I heve found to be working for stopping leaks is this.
Find a mud filled field.
Rush your truck into it at a spot that you will not get stuck (if you can guesstimate which spot is that).
Spin you tires a little and drive around to get a mud coat underneeth the truck.
Let the mud dry and become clay.
No more leaks.

kc8sfq · Post by **kc8sfq** » Mon Dec 17, 2007 5:53 pm

If Connie Rodd (GI's will remember her from P.S. Mag) is to be believed it's not even a reportable leak until it reaches 5 drips per minute. This from the BYOI for the M-37. At that rate I couldn't make a couple tanks of gas before I need to refill my transfer. Mine isn't that bad, but lets just say, I'll never have to undercoat anything aft of the transfer.

zaden · Post by **zaden** » Tue Dec 18, 2007 3:49 am

Well, after reading all of the comments and suggestions I have come to the conclusion that if you own a M37, it will leak, unless you rebuild it properly with new style seals and care.
It looks like I’m in the majority of folks that are not too worried with leakage and consider it a means of always keeping fresh oil where needed due to the refilling as required. When it comes time for a rebuild of any type I will certainly strive for a drip proof vehicle.
Thanks for all of the information!

Nickathome · Post by **Nickathome** » Tue Dec 18, 2007 7:55 am

This might have been said already. If so, I'll risk being redundant, are you willing to spend the money to fix the "minor" leaks? In my case I can answer that easily, "no". 1. I can't afford a rebuild. 2. If I am going to spend alot of $ on a rebuild, obviously its not going to be to simply stop leaks. It all boils down to $.

Again I'll be redundant in saying that a few drips here and there are no real concern to me. Yes, a half quart of gear oil suddenly appearing on the floor, or over the course of a week's time would be a major issue. However a spot the size of a silver dollar on the tarp or in the drip pan once a month, is a non issue really. As for many of us I presume, our trucks are playthings, secondary vehicles if you will, so a small leak is no big thing. IMO, the rebuild scenarios mentioned are but one end of the spectrum, again a $ lined end of the spectrum, but one solution.

Oil leaks

YF-12A SR-71

leaks

Leaks