Go Back  RCU Forums > Glow Engines, Gas Engines, Fuel & Mfg Support Forums > Everything Diesel
Reload this Page >

Black Oil coming out of exhaust qustion?

Notices
Everything Diesel Discuss R/C Diesel engines here.

Black Oil coming out of exhaust qustion?

Old 05-04-2005, 11:08 AM
  #1  
jstanton
Thread Starter
My Feedback: (14)
 
jstanton's Avatar
 
Join Date: Aug 2002
Location: Millington, TN
Posts: 3,224
Received 22 Likes on 22 Posts
Default Black Oil coming out of exhaust qustion?

I have a Magnum 75XL that I had AJ build a head form. AJ did a great job and I have the engine turning a MAS 14x6 at 9300 and she sounds real good once it is warmed up. I have black oil coming out of my exhaust. Is this normal or am I a little to lean? I had some leaks on my engine around the carburetor and exhaust. I used some red engine RCV to seal the leaks and it seams to be running great except for the black oil. Any help is greatly appreciated.

Thanks
Old 05-04-2005, 11:10 AM
  #2  
jstanton
Thread Starter
My Feedback: (14)
 
jstanton's Avatar
 
Join Date: Aug 2002
Location: Millington, TN
Posts: 3,224
Received 22 Likes on 22 Posts
Default RE: Black Oil coming out of exhaust qustion?

I forgot to add I am using the standard Davis diesel fuel.
Old 05-04-2005, 11:26 AM
  #3  
donkey doctor
Senior Member
 
Join Date: Nov 2002
Location: Lake Cowichan, BC, CANADA
Posts: 1,341
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Black Oil coming out of exhaust qustion?

Hello Jim; I ran my Irvine 40 diesel at the flying field a few months ago, the fellow that was holding the plane had his new S 10 pickup parked just behind the fence where we were doing this. I just ran a tank of fuel through the engine, just enough to get the carb dialled in. Three weeks later I see the same guy at the field but he now has a new Montana instead of his new S 10. I ask him about the Montana, he says the soot from my diesel covered his S 10 so bad that he had to trade it in for another vehicle.

In short, I haven't found a way to eliminate the soot from diesel exhaust. The best I have come op with is to use a long piece of surgical tubing to divert the soot away from the plane. I tie the open end to the bottom of the landing gear. I tried tuning the carb to eliminate the soot, but it would barely run at that setting, so that's not the answer.

I have a few old Mills diesels that don't seem to make as much soot as the Irvine, but they don't make as much power either.
Old 05-04-2005, 12:55 PM
  #4  
knarF
Member
 
Join Date: Nov 2004
Location: None, NETHERLANDS
Posts: 84
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Black Oil coming out of exhaust qustion?

Got off guard when I noticed black oil from my exhaust engine too (when i started with diesels)
Now i know its no big deal. My diesels run very smooth and powerfull, but all have black smelly residu.

You get used to it................in time
Old 05-04-2005, 01:15 PM
  #5  
Hobbsy
My Feedback: (102)
 
Hobbsy's Avatar
 
Join Date: Dec 2001
Location: Colonial Beach, VA
Posts: 20,370
Likes: 0
Received 17 Likes on 17 Posts
Default RE: Black Oil coming out of exhaust qustion?

If your Missus doesn't holler about the way you smell when you come home from flying Diesels, your doing something wrong.
Old 05-04-2005, 01:27 PM
  #6  
Motorboy
 
Motorboy's Avatar
 
Join Date: Feb 2004
Location: Bergen, NORWAY
Posts: 2,232
Likes: 0
Received 1 Like on 1 Post
Default RE: Black Oil coming out of exhaust qustion?

Soot are not danger for the engine, it is a product of burned kerosene and if the fuel has medicinal castor oil, it will produce black sludge. Nothing to worry about this soot so long the engine are running normal.

Jens Eirik
Old 05-04-2005, 04:05 PM
  #7  
Jim Thomerson
Senior Member
 
Join Date: Oct 2002
Location: Austin, TX
Posts: 4,086
Likes: 0
Received 1 Like on 1 Post
Default RE: Black Oil coming out of exhaust qustion?

If you are getting black exhaust, you should suspect that the engines is running overcompressed, which has no virtue. A diesel running lean will miss like it is undercompressed and then die.

Jim
Old 05-04-2005, 04:23 PM
  #8  
jstanton
Thread Starter
My Feedback: (14)
 
jstanton's Avatar
 
Join Date: Aug 2002
Location: Millington, TN
Posts: 3,224
Received 22 Likes on 22 Posts
Default RE: Black Oil coming out of exhaust qustion?

Thanks for all the help guys. It looks like I have nothing to worry about. I'll go flying tomorrow and see how it does. I have my Magnum 75xl diesel on a scratch built Right Angle with a 61" wing span. It should be more than enough power with a MAC 14x6 prop at 9300 rpm

Thanks Again Guys
Old 05-05-2005, 08:07 PM
  #9  
vauxhall
Senior Member
 
Join Date: Apr 2003
Location: SydneyNSW, AUSTRALIA
Posts: 581
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Black Oil coming out of exhaust qustion?

I mixed some fuel for my C/L P.A.W. 09 last weekend, and for a change used distillate ( truck fuel ) instead of kerosine. The plane was covered in black oily goo, maybe the distillate has additives, detergents, to keep engine internals clean, and blows ALL the soot out the exhaust port. I don't know, but never been this bad running on kero. Does Davis fuel list kero or distillate as the ingredient? .......John
Old 05-05-2005, 08:48 PM
  #10  
AMB
 
Join Date: Jun 2003
Location: winter park, FL
Posts: 6,748
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Black Oil coming out of exhaust qustion?

Davis uses kero --truck fuel here is #2 heavier grade distillate kero is #1 which is very similar to jet engine fuel the JP grades
if running # 2 oil in your mix will have a very dirty sooty exhaust (kero burns cleaner) In the US Davis fuel is available
I use his 1/2A in the small stuff and ABC mix in the larger engines which are all BB his plane fuel is used for bushing engines OS LAs
for example my exhaust is a light grey in color on some engines the residue dripping out is black others a dark amber in color
but all run fine martin
Old 05-05-2005, 11:22 PM
  #11  
Motorboy
 
Motorboy's Avatar
 
Join Date: Feb 2004
Location: Bergen, NORWAY
Posts: 2,232
Likes: 0
Received 1 Like on 1 Post
Default RE: Black Oil coming out of exhaust qustion?

The model dieselengine running with autodiesel are overlubricated, can not hurt the engine.
Same with the dieselpump in the automobile are lubricated of autodiesel. You know why we are never using the autodiesel in our the kerosene lamp cause smell and much soot.
My engines are often used with autodiesel in many years, not sign to wear, good compression.

Jens Eirik
Old 05-06-2005, 12:39 AM
  #12  
AMB
 
Join Date: Jun 2003
Location: winter park, FL
Posts: 6,748
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Black Oil coming out of exhaust qustion?

Motorboy totally agree will not harm engine justs throws more stuff out the exhaust I should have said they run a little cleaner on the kero base( #1 fuel) in many full size injector pumps the fuel lubes and cools the pump
Old 05-24-2005, 02:09 PM
  #13  
ddd
 
Join Date: Sep 2002
Location: Smyrna, TN
Posts: 413
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Black Oil coming out of exhaust qustion?

The byproducts in the exhaust of a running alcohol (glow) are water vapor and CO2. The exhaust residue on your glow powered plane is loaded with unburned fuel thus it is clear. The exhaust of gasoline or diesel are unburned Hydrocarbons and carbon and if a 2 cycle, engine oil. That's why the exhaust you see coming out of a glow engine is white clouds just like what you see in the sky (water vapor) whereas the gasoline or diesel is gray smoke. The oily residue in gasoline engines is a function of low oil content in the fuel. The black oily exhaust residue from the diesel is normal and is nothing more than carbon mixed with oil but not cut by unburned kerosene. The lighter the color say brown or golden brown in a very rich diesel thus diluting up the exhaust with unburned fuel.
Old 05-25-2005, 02:29 AM
  #14  
fiery
My Feedback: (2)
 
Join Date: Feb 2002
Location: Hervey Bay Queensland, AUSTRALIA
Posts: 2,994
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Black Oil coming out of exhaust qustion?

Mr Davis

Thanks for that excellent explanation.

I could never understand why my Irvine .20 diesel always had a honey colour exhaust, and my PAW's (.35,40 and .60) always had the typical black colour.

I guess I was running my Irvine undercompressed. After hundreds of flights, it still runs as well as the first broken-in runs!

I am looking forward to running diesels again. As a further question, I have access to jet A1 fuel, is there any benefit to using this instead of kerosine? Too my mind, they should be much the same. I wouldn't use "truck" bowser distallate as I hate the smell of it.

My favourite is low odour "white" kerosine. More expensive, but no nauseating kero smell. I love the ether exhaust smell though!
I never understood why the gl*w brigade find it off putting.

fiery
Old 05-25-2005, 06:31 AM
  #15  
AMB
 
Join Date: Jun 2003
Location: winter park, FL
Posts: 6,748
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Black Oil coming out of exhaust qustion?

I do not know if any advantage over kero except maybe odor it is a very high grade kero it will work fine
I myself having used Davis fuel for years do not have any issues with the smell and as mr Davis said " Once in the air who notices?
maybe the birds"Using clorox around the home for cleaning is not pleasant, funny Farmers, boat owners,construction equipment
operators running full size diesels seem to have no issues with it , A little oil to clean off the plane , well do not fly glow or diesel
maybe those folks should stick to electric martin
Old 05-25-2005, 09:16 AM
  #16  
ddd
 
Join Date: Sep 2002
Location: Smyrna, TN
Posts: 413
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Black Oil coming out of exhaust qustion?

The Irvine is running rich that is why the exhaust is honey colored. Jet A is very pure kerosene with no water or other impurities and thus you can use it, your diesel will not know the difference. The odorless kerosene gives up a small amount of power do to the loss of a very light fraction of the kerosene that has been removed to reduce the odor. As for the truck fuel never use the stuff or #1 diesel which is thinner. So to recap. No # 2 or # 1 diesel as it is to heavy a distillate to burn properly in a small diesel engine, but you may use Jet A or kerosene. Enough said I think on fuel. In the USA there are three commercial sources of the stuff and for overseas people we furnish formulas to make your own. Now go out and fly diesel its fun and reliable.
Old 05-28-2005, 09:18 PM
  #17  
fiery
My Feedback: (2)
 
Join Date: Feb 2002
Location: Hervey Bay Queensland, AUSTRALIA
Posts: 2,994
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Black Oil coming out of exhaust qustion?

Mr Davis, thank you again for your further advice .

As I will shortly be obtaining some ether to make up fuel (), may I also ask your view on the use of synthetic oil in diesel fuel?

I have 5 litres of "Motul Micro", a synthetic oil which is not well known in the US, but elsewhere is highly respected as being on of the best synthetic lubricants around for use in methanol powered model engines (the common name for which shalt not be uttered on these pages )

I was thinking of making my diesel fuel up with a formula cof 11% castor, and 11% of this synthetic oil , 33% ether, 43% kerosene or JetA1 and 2% Wynns deisel anti-knock as a DII .

Is this OK? Or, is it still the considered view that diesels really require an "all castor oil" lubrication package to properly protect against the rigours of diesel use, and to ensure longevity?

The engine selected for my re-entry to the joys of diesel will be an MVVS .49 with your "conversion" head. The engine has never been run to date. Your instructions suggest to break it in as a "methanol burner" using the standard head. Is this truly necessary? The Irvine factory .20 and .40 diesels did not have this benefit.

My Irvine .40D is still in its box, but the .20D has been well used, and has been operated exclusively as a diesel from day 1.

Regards

fiery
Old 05-31-2005, 09:08 AM
  #18  
ddd
 
Join Date: Sep 2002
Location: Smyrna, TN
Posts: 413
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Black Oil coming out of exhaust qustion?

I'm glad your having fun, but remember our policy is not to talk about formulas on public forums for legal reasons. Within the USA there are three suppliers of diesel fuel and thus there is not reason to make your own and possible hurt yourself or the engine. I have never found a subject in this hobby with more miss information then the making of model diesel fuel. The cost savings in this hobby is not on making your own fuel its on not crashing as much.
On the subject of oil however always use castor as your dominant part of the lube package glow or diesel.
Old 08-21-2005, 03:40 AM
  #19  
andrew b
Senior Member
 
andrew b's Avatar
 
Join Date: Aug 2005
Location: Wyke, Bradford, UNITED KINGDOM
Posts: 196
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Black Oil coming out of exhaust qustion?

ORIGINAL: hobbsy

If your Missus doesn't holler about the way you smell when you come home from flying Diesels, your doing something wrong.
My Missus hand launches our models, she has got an old tracksuit (it USED to be pink) especially for flying days. PAW 35's chuck out a lot of delicious smelly goo. Fuel is standard Model Technics D1000 with an additional 5% castor oil and 5% "BP ultimate" car diesel fuel
Old 08-21-2005, 07:29 PM
  #20  
AMB
 
Join Date: Jun 2003
Location: winter park, FL
Posts: 6,748
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Black Oil coming out of exhaust qustion?

Andrew D Why are you adding car diesel to model technics premix fuel?? Using davis here in the USA whether 1/2 A or ABC mix
I use it as is, I am pretty sure that your model technics fuel is fine as is and think there are several formulas of it available in the
UK. I have never had a problem with the Davis fuel, corrosion , burned bearings, seizings etc. I really do not think you have to
alter your fuel, the make up of the fuel with the kero and even the small amount of soot produced helps lubricate too.as pointed
out by Mr davis many times over the years. this and the cooler running of the model diesel is why they outlast their glow counterparts
no nitro no alcohol to adsorb moisture. about the only way to ruin a diesel is run it over-compressed which will over heat and overstress
it and of course using inproper fuel martin
Old 08-21-2005, 07:47 PM
  #21  
AMB
 
Join Date: Jun 2003
Location: winter park, FL
Posts: 6,748
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Black Oil coming out of exhaust qustion?

dup post of abovw

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.