RE: BME 115 Any Field Reports?

RE: BME 115 Any Field Reports?
View related threads: (in this forum | in all forums)

Logged in as Guest

Users viewing this topic: none

Printable Version

All Forums >> Glow Engines, Gas Engines, Fuel & Mfg Support Forums >> Gas Engines >> RE: BME 115 Any Field Reports?

Page: << < prev 6 7 [8] 9 10 11 12 13 14 15 next > >>

Login

Message

<< Older Topic Newer Topic >>

RE: BME 115 Any Field Reports? - 4/28/2007 4:55:24 PM

Posts: 12358
Joined: 2/25/2002
From: Central, CA, USA
Status: offline

Must be talking about a guy over at F/G. That "unofficial" BME expert

_____________________________

If you can''t fix it with a hammer, you have an electrical problem.

(in reply to dick Hanson)

RE: BME 115 Any Field Reports? - 4/28/2007 4:55:44 PM

RTK

Posts: 4089
Joined: 4/20/2003
From: CENTRAL , CA, USA
Status: offline

quote:

ORIGINAL: dick Hanson

I have never seen an engine lean out as it unloads .

I hope he wasn't referring to me Silversurfer.

Dick, there seemed to be some bad carbs on the first round. Some would lean out some would not. The new carb Keith is using does Not exhibit this. I believe Louis Salas and Keith got together and thought it had to do with the design of the first carb. If you have a WGA look how the high speed circuit feeds into the venturi with that brass insert. Push it out and you will see.

I think the 115 is the only 100cc class engine to use 6 transfer ports, it gets thirsty at times

(in reply to dick Hanson)

RE: BME 115 Any Field Reports? - 4/28/2007 6:07:01 PM

BTerry

Posts: 966
Joined: 4/24/2002
From: Silverdale, WA, USA
Status: offline

quote:

ORIGINAL: RTK

quote:

ORIGINAL: dick Hanson

I have never seen an engine lean out as it unloads .

I hope he wasn't referring to me Silversurfer.

No, I think he was referring to the person whose signature claims this...

(in reply to RTK)

RE: BME 115 Any Field Reports? - 4/28/2007 6:07:39 PM

Posts: 6413
Joined: 3/26/2002
From: Kannapolis, NC, USA
Status: offline

dick Hanson u see you are learning from the expert here lol lol yeah we may not want to take any advice from him.

_____________________________

smooth as silk!

(in reply to dick Hanson)

RE: BME 115 Any Field Reports? - 4/28/2007 9:03:04 PM

Posts: 10271
Joined: 12/12/2001
From: slc, UT, USA
Status: online

yeh-- It puzzled me that an engine with the load REDUCED, would go lean
If logic is used - it follows then, that loading the engine will make it go rich.
(probably "dynamic physics" at work)
But the fact that the engine revs faster in level or flight (or a dive) infers it is doing more work --which it isn't .

_____________________________

I am watching you
Libby

(in reply to krayzc-RCU)

RE: BME 115 Any Field Reports? - 4/28/2007 10:12:31 PM

RTK

Posts: 4089
Joined: 4/20/2003
From: CENTRAL , CA, USA
Status: offline

I am only an expert on my own opinion

Dick take a look at the high speed circuit on a WGA. The brass insert that feeds that circuit protrudes into the venturi, when removed you will see a fiber glass disk in the end. That is the key. It creates a flow restriction, or that is "my" opinion. If you call Louis Salas (head honcho at Walbro) he could give you the exact reasons. I have not talked to him about this, but have for other unrelated items. He's a real nice and knowledgeable guy. Maybe it has to do with the six transfer ports and timing really needing more juice

I have owned the 110 along with the 115 from their inception. My flying might not be all that good but I have experimented/played with both a lot.

quote:

ORIGINAL: dick Hanson

But the fact that the engine revs faster in level or flight (or a dive) infers it is doing more work --which it isn't .

Just better volumetric efficiency at higher rpm's

Probably something to do with porting and timing which I am know I am NO expert on.
Hp=torque x rpm /5250 or something like that.

(in reply to dick Hanson)

RE: BME 115 Any Field Reports? - 4/28/2007 11:49:09 PM

Posts: 10271
Joined: 12/12/2001
From: slc, UT, USA
Status: online

My comment has nothing to do with any particular engine - or carb setup -
restated : You are either loading the engine -(using more power)or unloading it (using less power )
less power takes less fuel
more power takes more fuel.
was a carb fitted which leaned out as flow thru the carb increased?
I don't se why that would intentionaly be done
but
If the carb was mismatched in size-typical when an overly large carb is used - that CAN and does happen but not having one of those engines -I won't say anything about the carb selection.
these carbs are designed around specific engines (based on airflow potential) doing specific tasks.
a you have seen there are jillion versions of given bores etc.. I have a box of carbs -some look exactly like the others --till you get really picky- then you see why one will respond better at low speeds some wil not choke well etc..
I was addressing terminolgy: UNload (reduce load ) --load (increase load)

_____________________________

I am watching you
Libby

(in reply to RTK)

RE: BME 115 Any Field Reports? - 4/29/2007 12:12:58 AM

Posts: 1236
Joined: 10/24/2004
From: Altaville, CA, USA
Status: offline

Grrrrrrrrrrrrrrr. Waiting for an order from TBM and was just checking out props on their site and see that they have 27x8 and 28x8 PT props in YEA!!!!! But how bout some advertising guys? Now I have to make a new order

_____________________________

I didn''t put the bullet in the fire and you quit talking about my mother! "Cosby, Shop Class, 1968 or so"

(in reply to dick Hanson)

RE: BME 115 Any Field Reports? - 4/29/2007 12:17:41 AM

Posts: 1236
Joined: 10/24/2004
From: Altaville, CA, USA
Status: offline

Dick; I could melt the teflon couplings if I did a couple full throttle passes on the old carb. Many HS passes on the new carb later, no problems so far.

_____________________________

I didn''t put the bullet in the fire and you quit talking about my mother! "Cosby, Shop Class, 1968 or so"

(in reply to altavillan)

RE: BME 115 Any Field Reports? - 4/29/2007 12:59:58 AM

Posts: 10271
Joined: 12/12/2001
From: slc, UT, USA
Status: online

sounds good to me !
I have run the large bore Walbros on myZDZ 160-and the Evolution 116 runs them on their 116 -with a nifty little low speed needle auto increase setup. it works! but the linkage is a b itch to setup.
In trying large bore carbs --the Tillotson seems better --in most cases but they also have some occasional goofs.
most of the time -I set my carbs for a bit fat in level cruise and then let em get CLEAN on verticals- keeps power up and heat down
On pipes this setup if firewalled in a dive --goes way rich and won't rev up -but on a open muffler -will rev well into the 8000 range - -which is just wasted rpm.
if power is up and heat is tolerable --you have a good setup. no witchcraft needed -

_____________________________

I am watching you
Libby

(in reply to altavillan)

RE: BME 115 Any Field Reports? - 4/29/2007 2:57:19 AM

RTK

Posts: 4089
Joined: 4/20/2003
From: CENTRAL , CA, USA
Status: offline

quote:

ORIGINAL: dick Hanson

I was addressing terminolgy: UNload (reduce load ) --load (increase load)

Load on an engine does not necessarily have a direct correlation with volumetric efficiency or flow, but a lot of the time Rpm's do. You can load the crap out of and engine at a low RPM and the air flow though the carb will not be as high a volume as an engine free wheeling at high rpm. I "feel" some of the WGA's would not deliver the right air/fuel mixture when air flow though the carb exceeded a certain point. Thus causing a leaning in the air fuel mixture. Next time I talk to Louis Salas or Keith I will ask them if they feel my ASSumptions are plausible, and again I could be all wet. But I do know the new carb is much better

(in reply to dick Hanson)

RE: BME 115 Any Field Reports? - 4/29/2007 5:16:19 AM

Posts: 10271
Joined: 12/12/2001
From: slc, UT, USA
Status: online

well actually load does affect flow -- seriously

here is an example -tho on an automobile engine
If you put a vacuum gauge in the manifold the readings run all over the place - related directly to rpm AND load
The classic problem was when a large carb was opened too soon in the power band --this dropped vacuum -then the engine seriously bogged down -the fuel mix went bonkers . the old fix was progressive carbs or dual stage (4barrel ) carbs
with FI this is not an issue as the computer just summs up th inputs and decided best fuel flow and spark setting.
My first experience with competition carb setups was getting three Stromberg 48's to accelerate smoothly- I ended up with leanest power valves - shortest pump strokes and a slight delay in end carbs opening. But it would spin the tires upon stepping on the throttle -The typical result was a bogging down. carbs is carbs - they all rely on correct pressure differences plus flow to make fuel flow. In our Walbros- -no pump- no power valve -so the low>high speed discharge setups must be spot on for the particular engine -as well as having carb sized right and prop load matched of course.

:

< Message edited by dick Hanson -- 4/29/2007 7:27:25 PM >

_____________________________

I am watching you
Libby

(in reply to RTK)

RE: BME 115 Any Field Reports? - 4/29/2007 3:56:45 PM

Posts: 6498
Joined: 1/25/2002
From: Hesperia, MI, USA
Status: offline

Just a general reply about Walbro carbs. Some have a well that holds a small amout of fuel to en-richen the fuel mix ...acting like a excelerator pump. Capt,n

_____________________________

I never met a engine I did not like!

(in reply to dick Hanson)

RE: BME 115 Any Field Reports? - 4/29/2007 7:26:58 PM

Posts: 10271
Joined: 12/12/2001
From: slc, UT, USA
Status: online

enrichening/accelerator pump? on these small ones ?
which models-if you have that info handy?
Have not seen one .

_____________________________

I am watching you
Libby

(in reply to captinjohn)

RE: BME 115 Any Field Reports? - 4/29/2007 8:23:54 PM

Posts: 10
Joined: 4/26/2003
From: Northern Arizona
Status: offline

2 types, one is a plunger operated by a cam on the throttle shaft, the other is just a hole in the shaft that lines up with another in the body...
Many Walbros have them, don't have the book handy, they're all there...

(in reply to dick Hanson)

RE: BME 115 Any Field Reports? - 4/29/2007 8:52:02 PM

Posts: 10271
Joined: 12/12/2001
From: slc, UT, USA
Status: online

In the sizes/types we use?

_____________________________

I am watching you
Libby

(in reply to Herby 1)