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92 Sqn. Philstyle (QJ-P)
Apr-17-2013, 04:32
Hello folks,

Last night I was doodling about in the 109E4-N, trying to learn the beast a bit better.

At one point I got airborne, and flew up to altitude (~6.5km). I was pretty sure that I was keeping the RPM below the magic 2500, but I had been using the WEP a bit (to see what impact it made) so my ATA had been over 1.4 for a wee while at times. I had the oil radiator at about 35% and I'm not sure how much the other Radiator was open... but I'm pretty sure it was not closed.

After about 10 minutes the engine started shaking. I figure I blew something, but I'm not sure what, because I didn't have the damage information showing. There was also nothing venting out the back as a result of this.

Anybody have an idea what I might have blown?

The strange thing was, I was able to continue flying for at least 20 more minutes, without losing any speed, or without the engine completely failing after this. The only negative effect was the shaking, which was quite tolerable, I could even use the gun-sight quite well even with the shaking. It wasn't until I was over Hawkinge and I perforated the water radiator (flak) that the engine finally seized up.

Kling
Apr-17-2013, 05:20
Hello folks,

Last night I was doodling about in the 109E4-N, trying to learn the beast a bit better.

At one point I got airborne, and flew up to altitude (~6.5km). I was pretty sure that I was keeping the RPM below the magic 2500, but I had been using the WEP a bit (to see what impact it made) so my ATA had been over 1.4 for a wee while at times. I had the oil radiator at about 35% and I'm not sure how much the other Radiator was open... but I'm pretty sure it was not closed.

After about 10 minutes the engine started shaking. I figure I blew something, but I'm not sure what, because I didn't have the damage information showing. There was also nothing venting out the back as a result of this.

Anybody have an idea what I might have blown?

The strange thing was, I was able to continue flying for at least 20 more minutes, without losing any speed, or without the engine completely failing after this. The only negative effect was the shaking, which was quite tolerable, I could even use the gun-sight quite well even with the shaking. It wasn't until I was over Hawkinge and I perforated the water radiator (flak) that the engine finally seized up.

Too high oil temperature will give you this effect.
Once the oil temp had become too high, the engine will shake for the rest of the flight even if you open the oil radiator completely.

To prevent this, keep oil radiatorbar 100% .
I usually keep my 109 sater radiator at ca 50% for cruise and 80% for normal climb but 100% for combat.

At high speed when running away at low atlitude, ca 30% is enough.

Hope this helps! ;)

92 Sqn. Philstyle (QJ-P)
Apr-17-2013, 05:55
Thanks Kling.


Apart from the shaking however, the blown oil radiator had no real affect on performance. I could still zoom around for 15-20 minutes at high altitude in level flight at 30kmh+ indicated, and carry out high speed (~650kmh) dives with 2500rpm. Is this normal, or does it normally give you 2-3 minutes flying time before it seizes up?

One the water radiator blew, I lasted about 3 minutes.. but the oil radiator damage seemed ignorable ...

9./JG52 Hans Gruber
Apr-17-2013, 06:06
If there wasn't oil on the windscreen the the oil radiator did not blow. There is a level of engine damage where it only shakes. It will no longer produce max output and you won't have a chance against a competent opponent.

92 Sqn. Philstyle (QJ-P)
Apr-17-2013, 06:12
Thanks notafinger. I suspect that is the level of damage I had experienced.

I appreciate the clarification.
I really need to have the damage-information showing when I fly the 109, given that I'm so much less familiar with it than the spitfires.

9./JG52 Ziegler
Apr-17-2013, 06:58
Phil,

I usually leave my oil rad open 100% and only manipulate the coolant rad in flight. If you are on single player and step outside, you can see that the coolant rads can be more aerodynamic as you close it, but the oil rad is just out there on the side and does not really change shape as you close it. The flap/valve is internal. The N model is a great bird. Welcome to the Dark Side :thumbsup:

vranac
Apr-17-2013, 07:10
Put oil rad on 50% and for air you have indicator on the wing if you move your head right and zoom it.
Put it in the position 1/4 out and forget the rads at least till 6 km.

Kling
Apr-17-2013, 07:13
Thanks Kling.


Apart from the shaking however, the blown oil radiator had no real affect on performance. I could still zoom around for 15-20 minutes at high altitude in level flight at 30kmh+ indicated, and carry out high speed (~650kmh) dives with 2500rpm. Is this normal, or does it normally give you 2-3 minutes flying time before it seizes up?

One the water radiator blew, I lasted about 3 minutes.. but the oil radiator damage seemed ignorable ...

Once you have an oil leak you have 2mins and 10 secs before complete failure.
Once you have water radiator leak, you as well have 2 mins and 10 secs before complete failure of the engine.

If you at one point overheat the oil (not the same as oil leak) you can keep flying, with a slight loss of power but alot of shaking.'
Hope this clears it up!

Kling
Apr-17-2013, 07:13
If there wasn't oil on the windscreen the the oil radiator did not blow. There is a level of engine damage where it only shakes. It will no longer produce max output and you won't have a chance against a competent opponent.

Noone mentioned anything about leaking oil.
we said oil overheat! ;)

9./JG52 Hans Gruber
Apr-17-2013, 08:14
Noone mentioned anything about leaking oil.
we said oil overheat! ;)

Uh...no, he said blown oil radiator.

92 Sqn. Philstyle (QJ-P)
Apr-17-2013, 08:16
Uh...no, he said blown oil radiator.

"Blown" is my colloqual way of saying broken. In lieu of knowing exactly what was broken, all I could say was blown.

Either way, no need to pick about at the terms employed, the problem appears to be solved now, so thanks for your input, both.

Kling
Apr-17-2013, 12:21
Uh...no, he said blown oil radiator.

No he ASKED if he might have blown something... Which he hadnt.
Which is what i explained. When the oilradiator is hit it will say so.

Anyway problem is solved so end of discussion

III./ZG76_Keller
Apr-17-2013, 13:54
Phil,

I usually leave my oil rad open 100% and only manipulate the coolant rad in flight. If you are on single player and step outside, you can see that the coolant rads can be more aerodynamic as you close it, but the oil rad is just out there on the side and does not really change shape as you close it. The flap/valve is internal. The N model is a great bird. Welcome to the Dark Side :thumbsup:

The oil cooler is under the engine on a 109, I think you're thinking of the supercharger air intake on the left side. The further open the oil cooler is the more drag it will cause.


Oil Cooler
http://farm3.staticflickr.com/2495/3903654217_40df1229f8_z.jpg?zz=1

AA_Engadin
Apr-17-2013, 16:36
The oil cooler is under the engine on a 109, I think you're thinking of the supercharger air intake on the left side. The further open the oil cooler is the more drag it will cause.


Oil Cooler
http://farm3.staticflickr.com/2495/3903654217_40df1229f8_z.jpg?zz=1

Hi ATAG_Keller, where did you take that photo at? Hendon perhaps?

Thanks.

AA_Engadin.

III./ZG76_Keller
Apr-17-2013, 17:44
Not my photo, from the Internet.

DK_
Apr-18-2013, 15:30
Hello folks,

Last night I was doodling about in the 109E4-N, trying to learn the beast a bit better.

At one point I got airborne, and flew up to altitude (~6.5km). I was pretty sure that I was keeping the RPM below the magic 2500, but I had been using the WEP a bit (to see what impact it made) so my ATA had been over 1.4 for a wee while at times. I had the oil .......p.

I thought that the E4-N did not have WEP. I edited your post for brevity in my response

My techniques
Climb/slow high power/fight
Oil open 80-100
Water open 3/4-full

Level speed above 300-350
Oil open 50
Water open 1/4-1/2

Cheers

9./JG52 Ziegler
Apr-19-2013, 07:32
Oh yep Keller thanks. That's exactly what I was looking at up on the left side. :thumbsup:

Royraiden
Apr-19-2013, 07:47
Ive had a somewhat similar problem but only when boom and zooming high speeds, sometimes I blow my engine and I dont know why.What are the radiator settings for this situations?

TX-Gunslinger
Apr-19-2013, 09:49
Thought I'd post a picture of the Oil Rad itself. This is from E-1, #790. It's interesting in that the cooler "flap" appears fixed and the aircraft at some point was upgraded to E-3 config. Since it's a museum piece, all kinds of things are possible.

https://webspace.utexas.edu/joem/CLIFFS%20OF%20DOVER/Bf109E1-790-E3/109E3%20Oil%20Cooler%20Detail.jpg

https://webspace.utexas.edu/joem/CLIFFS%20OF%20DOVER/Bf109E1-790-E3/109E3%20Oil%20Cooler%20Detail2.jpg

92 Sqn. Philstyle (QJ-P)
Apr-19-2013, 10:06
Ive had a somewhat similar problem but only when boom and zooming high speeds, sometimes I blow my engine and I dont know why.What are the radiator settings for this situations?

RPM over-speed probably.

When in the dive, reduce your RPM - keep it below 2500.
then as soon as you hit the bottom of the dive, start bringing the RPM back up.