Warbird Information Exchange

ZRX61, I'm not sure where you get your info from!

That was the point of the question, there is no recommended or mandatory TBO.

I work on several with over 1000 trouble free hours on them.

The only oil related problems I have encountered, other than rust is where the last person to put it together blocked oil passages with silicone!

From someone will 30 years of operating Merlins in 20 different P51's, plus Merlins in Spits during that time....

& I didn't say the 400/600 was cast in stone. Every engine is different, that was just the *about then* hours, which ties in with what a couple of the other guys have said. There's not a whole lot of difference between 600 & 650 (altho that could be 2 seasons of some airframes)

I'll ask the local guru in the morning & see what he says.

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Those who possess real knowledge are rare.

Those who can set that knowledge into motion in the physical world are rarer still.

The few who possess real knowledge and can set it into motion of their own hands are the rarest of all.

I'm surprised that no one mentioned Marvel Mystery Oil, STP, or Slick 50......

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Ed L.

Glenn, as an old Indy mech here, why do guys not use oil heaters & such on these engines? I guess I'd want a heater and pre-oiler prior to flight. I think I'd know long enough in advance of my flight to be able to plug the heater in and then run the oil through before starting.

Am I making things too complicated? STC's or the such prevent this idea?

Hey it's getting cold up here. Wanna come visit? Might have snow soon.

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"There are old pilots and bold pilots but few old, bold pilots."

I stole this a few years back and rewrote it for the display community. )))

"There are old pilots and there are bold pilots. The trick in becoming an old pilot is in knowing exactly when to be, and NOT to be, bold"
Dudley Henriques
"Zero Error Margin"
Des Barker

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Dudley Henriques
International Fighter Pilots Fellowship

Remember, these engines were built to operate in the far flung reaches of the globe in all conditions.
The tolerances are not micro precision as in some of the finicky race cars.
On the Pond Racer, the Nissan V-6s required pre heat, even at Reno in the heat there.
We used heater strips bonded onto the oil tank on the T-6 and P-51s when we were at Northeast Philly to heat the oil. Sometimes we would use a salamander heater aimed at the engine as well.
Don't miss those days.
Also the P-51 and the Spit have pre-oilers.
Rich

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Rich Palmer

Remember an Injured Youth
benstear.org
#64- Stay Strong and Keep the Faith

BOOM BOOM, ROUND ROUND, PROPELLER GO

Don't Be A Dilbert!

Point taken. We heated the oil first with horid stick heaters in the tanks, then blanket heaters on the outside of the tanks, along with water block heaters for the races in Phoenix, Ontario, everywhere. Our objective was to get the engine to temperature prior to going out on to the track. We pulled spark plugs and then turned the engine over by pulsing the starter until oil pressure was indicated. Then we ran the starter constant and opened the fuel shut off until we had fuel blowing out the spark plug hole. Then warm up plugs and just prior to practice or qualifying/race, installed the race plugs. Quite a process I know. However, I'd think that at minimum, I'd preheat the oil and prelube using the pressure sump. My concern would be the typical long sit time between flights, short warm up time, high performance demand in a short period of time, and then back to the hangar to sit.

As far as clearances go, most racing engines have a bit more open clearances to reduce friction and promote oil flow. We used to run .003" on rod and main bearings pretty much as a rule of thumb.

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"There are old pilots and bold pilots but few old, bold pilots."

S Denison; good question about the pre heaters. I have one, but off hand I can't name another Spit or Mustang that does, though I am sure there must be some that I don't know about. Why don't almost all have them, well that is pretty much human nature. I don't even think the ones that I know of in Canada do. Why don't I have the Heinz warning device on mine; just haven't gotten to it yet, partly a matter of time and space to put it.

The simplest and basic heating device is a rubber electric pad that just glues on the the bottom of the engine, mine has one on the engine crankcase and one on the oil tank. It has a thermostat to prevent overheating and a short cord that you just plug into an extension cord to a normal 120 volt outlet. It will heat the oil up to about 75* in perhaps 3 hours. It cost less than $150 per pad and can be put on in an hour if you have the engine covers off for an oil change.

Lot's of people have preoilers, but it is a lot better to be pumping warm oil up into your engine, and have warm oil for start up, especially if you are using thick single grade oil. My preoiler flows into the whole system, not just the top end. On a cold morning you can sit in the cockpit and run the pump for about 2 minutes and see both the oil pressure rise slightly and the temp come up a little before start up. After start the oil is nice and warm and you wait for the rad temp to come up. If it is real cold we might use a ground hot air blower on the rads also, but if it is that cold, the pilot is probably waiting for a warmer time. Some guys have hangars, but they aren't always heated that warm overnight and sometimes you may be on a trip and away from the hangar. By the way, I don't leave mine plugged in all the time so condensation does not seem a problem.

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Bill Greenwood
Spitfire N308WK

Hey, you left out Bardahl Hydroil

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"They can teach MONKEYS to fly better than that"

http://www.heritageflight.org
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The Heinz system sounds really good, if I understand it correctly. However, is there a simple way and access for a simple screen filter on the/a main scavange line that can be inspected prior to and or after each flight? That was always the last step when we ran an engine on the dyno, "check the screen". It was an aluminum cast housing with a cap and locking mechanism, dual wing nuts in our applicationm but you opened the top, pulled the filter screen to inspect for metallic particles, if clean or acceptable, the engine went to shipping. If full of particles, we knew we had a problem and the engine went back to be torn down or at least have the pan dropped and the engine inspected.

Again, I am not on the inside of the Merlin/RR world so I don't know but it sure seems like some simple things to do to insure longer life potential (both engine and pilot).

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"There are old pilots and bold pilots but few old, bold pilots."

In regards to Allisons-
I know that we had a few torn up pistons in the late eighties and early nineties.
I changed heads and banks a couple times of the POF P-38 and also a couple P-40s and I believe the P-51A.
IIRC it had to do with the 100LL fuel being reformulated but it might have been due to JRS overhauls.
Rich
Edit- We also had the carbs reflowed to a different spec at this time due to the 100LL.

_________________
Rich Palmer

Remember an Injured Youth
benstear.org
#64- Stay Strong and Keep the Faith

BOOM BOOM, ROUND ROUND, PROPELLER GO

Don't Be A Dilbert!

S Denison, there are two screens on the bottom of the Merlin, see my first posts here. But unless you want to take off the side and bottom cowling, plus the air fliter (Spit), before every flight you can't access them. Opening them would also drain the internal engine, also not good pre start. And the prop fliter is finer and the Hovey type paper filters finer still if you were only going to check one source.

An oil change and check every 35 hours should catch most metal/dirt problems before they become major. Merlin reliability is good now, was good in the war, just takes a lot of care, and while you are doing it, Ray "has a look around", also.

The Heinz filter is really a warning device, chip detector, I think, that is what Gerry emphasized.

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Bill Greenwood
Spitfire N308WK

Correct. The Hinz filter is an early warning device designed to detect chips by two different methods in the same unit. Although it uses an Oberg type screen filter, it is not intended to be a primary filtering device. The chip magnet for ferris materials was a little too sensitve at first but has been rectified. It's a very effective add on that has already saved a couple airplanes.

John

Well I spoke with the engine guys.. I'm not going to get into a pissing contest about this, but I won't be taking any rides behind Merlins with 1000 hrs on them.
& after the talk of wear at that kind age I'm glad I won't be paying for the eventual O/Hs either

_________________
Those who possess real knowledge are rare.

Those who can set that knowledge into motion in the physical world are rarer still.

The few who possess real knowledge and can set it into motion of their own hands are the rarest of all.

If you have any spare seats in Merlin powered planes with 1000 hours on them, I can always find a spot on my dance card. I never got a chance to ride on one of the DC-4M airliners, but I'd love to; window seat please. You could pretend you were in a Lancaster, without the 109s! As for wear items, well that is why we do the oil change and filter inspections and oil analysis and also use a good Bracket airfilter. Of course, it is possible, I guess that there is some major wear that does not show up on these, though I don't know where the bits would go if not into the oil, maybe out the exhaust.

The most wear that I have seen in the oil analysis was run in after O H and also some silicon,(dirt) once when we had a air scoop door that was not closing right and let unfiltered ram air in on the ground.

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Bill Greenwood
Spitfire N308WK