Wanderlodge Owners Group  
BuyByeBlueBird.com
Donate

Go Back   Wanderlodge Owners Group > Mechanic's Corner > General

General Discussion of preventative/corrective maintenance and other technical issues regarding your coach that are not covered in other Mechanic's Corner categories (ex. refrigerators, water heaters, and compressors).

Site Search:
Reply
 
Thread Tools
  #1  
Old 07-01-2010
nfun2's Avatar
nfun2 nfun2 is offline
Senior Member
 
Join Date: Jun 2010
Location: winter-Yuma/summer-Boise Idaho
Posts: 139
Thumbs up Major engine components

Greetings,
For the benefit of a wannabe would someone be willing to explain the interaction of the turbocharger, supercharger and aftercooler in simplified terms?

TIA
__________________
Dennis Gloe
1985 PT40 "Den's Disco Den"
2002 Suzuki XL7 4X4
Reply With Quote
  #2  
Old 07-01-2010
jwasnewski jwasnewski is offline
Senior Member
 
Join Date: Jan 2008
Location: Dahlonega, GA
Posts: 1,111
Default

I will take a shot in very simple terms.
Turbo charger. A method of inducting air into the cylinders too create boost which creates more power without detonation in the cylinders. It operates from the exhaust created by the engine. Hence, the lag in response time.
Supercharger. A method of direct induction of air into the cylinders creating more power. It is a scavenge type induction system in that it robs power to create it. It is driven by belts but could be direct drive. It has relative instantaneous response time.
After cooler most commonly called inter cooler. Used on turbo charged engines to cool air being inducted into the engine cylinders. The volume is less when cooler and hence more air can be packed into the cylinders increasing boost.
Hopefully this is simply accurate.
__________________
Leroy Eckert
Dahlonega, GA

Former "Smoke N Mirrors" caretaker
Reply With Quote
  #3  
Old 07-01-2010
bwinter1946's Avatar
bwinter1946 bwinter1946 is offline
Senior Member
 
Join Date: Mar 2009
Location: Madera
Posts: 4,036
Default

Leroy is right.

I would add that supercharged or "blown" engines can have intercoolers also. Air when compressed heats up. That heat increases intake air temperature and reduces horsepower.

In addition, the Detroit 6V92 and 8V92 engines will have a supercharger (AKA blower) and a turbocharger. The 2 strokes must have a functioning blower to run. The turbo blows into the supercharger.

The "regular" 4 stroke diesels are normally aspirated (No blower or turbo) or turbo charged.
__________________
Brad Winter
Madera, California
1997, 37' BMC
1999, Jeep Cherokee, Toad
1970, VW Baja Bug, Alternate Toad
Reply With Quote
  #4  
Old 07-01-2010
Randy Dupree's Avatar
Randy Dupree Randy Dupree is offline
Forum owner
 
Join Date: Dec 2007
Location: Archer,Fl
Posts: 34,728
Default

what they are doing with superchargers or turbochargers is increasing the air to the engine,giving the engine more air increases power.
Cooling the air with an intercooler makes more power,cold air = HP.
to the engine.
Intercooler=aftercooler=charge air cooler.
all do about the same thing,cools the in-coming air
__________________
DO NOT SEND PM
email me at randy@randydupree.com only.

Randy Dupree
2000 LXI 43
Bainbridge,Ga.
Archer Fl.
www.buybyebluebird.com

randy@randydupree.com
Reply With Quote
  #5  
Old 07-02-2010
peteaeonix's Avatar
peteaeonix peteaeonix is offline
Former Bird Owner
 
Join Date: Jan 2008
Location: Ridgefield
Posts: 2,010
Default

Not all 4 cycle diesels are "normally aspirated." I believe that the Cat 3208 "turbo" engines are a 4 cycle design -- and quite clearly have a turbo charger. It adds about 50 HP if I recall correctly.

The Series 60 engines are all turbocharged. They use a "charge air cooler" (same effect as an intercooler) that is mounted outboard of the water radiator -- and looks much like a normal radiator.

On a DD Series 60 engine, it is important to realize that inspecting the radiator for clogging is hampered by the CAC. When stopped, there is a tendency for hot, oily mist from the breather tube to be drawn through the CAC/Water Radiator combination. For whatever reason, the CAC does not tend to build up any significant residue. However, my guess is that the water radiator 'heats' the oily mist, making it more sticky, allowing dust drawn through the CAC/Radiator to stick (but not stick to the CAC). Ultimately, the oily-dirt will build up to block the water radiator, significantly reducing its cooling effectiveness and potentially leading to an overheating situation.

This is a tendency with all rear engine coaches (not just Series 60 and not just Blue Birds). So regular inspection and cleaning of the CAC/radiator should be part of normal maintenance.

The DD 8v92 and 6v92 are supercharged engines. I'm not familiar with their specific layout or if they normally have a charge air cooler (intercooler). They are still subject the the radiator fouling.

An FC owner would have to comment on the existence and/or location of the intercooler, if one exists, on the 3208 turbo engine models.

While in automotive applications, turbo charging is frequently used to 'soup up' an engine (either directly from the factory or as an aftermarket installation). Some of the "bottle rocket" sub compacts take, for example, a car like a Toyota Corolla and add a turbo charger and some decorative skirts and deck lid airfoil to create a sporty version with 40 or 50 more horsepower from the same or a slightly modified version of the engine.

In diesels, the turbo charging is more often part of the basic design with engines sized for the application. The 42/43 foot 'birds with the Series 60 are sized with an engine of 470 to 500 hp using the turbo charger. No non-turbo version of the engine exists as far as I know. The Turbo (or supercharger) in a diesel engine delivers more power for the amount of fuel used. So while it increases horsepower, it also utilizes more of the chemical energy available from the diesel fuel giving better fuel economy for the horsepower generated.

This last concept might seem counter intuitive -- but consider two diesel engines of (say) 300 HP. One is turbocharged and the other is normally aspirated. Since the turbo unit is able to pump more air through the engine, it will burn the fuel more efficiently and get modestly better fuel economy than the equally powered NA engine. Since we're accustomed to seeing turbos used to increase horsepower, and the higher horsepower engines (naturally) use more fuel, we don't think of turbo as being an improvement in efficiency. But that is only an impression since the comparison is usually made considering the same engine with normal aspiration (e.g. a 3208 with 250 HP) and turbo charged (a 3208 with 300 HP). More horsepower requires burning more fuel -- but improved engine design can get deliver more energy from the fuel and waste less of the chemical energy as heat.
__________________

Pete Masterson
(former) 95 WBDA 42'
(now) 2011 Roadtrek RS-Adventerous
Ridgefield, WA
aeonix1@me.com
Reply With Quote
  #6  
Old 07-02-2010
GregOConnor's Avatar
GregOConnor GregOConnor is offline
Senior Member
 
Join Date: Jan 2010
Location: Romoland
Posts: 86
Default

pete, good assumptions but now like you I'm confused
__________________
Greg O'Connor
Romoland, CA
1994 wb40
Reply With Quote
  #7  
Old 07-02-2010
davidmbrady
Guest
 
Posts: n/a
Default

The latest generation of Detroit Diesels, DD15, use two turbochargers. One turbo does the normal job of compressing combustion air for the engine. The second turbo drives an output shaft that's geared into the engine, typically known as "turbo compounding". This allows for even more exhaust gas energy conversion to usable shaft power. Turbo compounding on the DD15 results in a 5% increase in fuel economy and an additional 50hp at the crankshaft.

http://www.layover.com/news/article/...ns--15127.html

On a side note, I'm in the process of R&Ring my CAC/Rad stack. Upon removal, I found no oily-dirt residue build up on the fins of the radiator. Perhaps there were changes made to the routing of the S-60 breather tube or to the CAC/Rad baffling used in the LXi versus the Wide-Body's, or perhaps Pete's engine exhibited more than the usual blow-by. After 105K miles, the radiator fins were clean but heavily corroded from road salt and de-icers.

Last edited by davidmbrady; 07-02-2010 at 04:45 PM. Reason: Added link.
Reply With Quote
  #8  
Old 07-02-2010
fxdwg fxdwg is offline
Senior Member
 
Join Date: Mar 2008
Location: okc
Posts: 3,843
Default

Okay, so where does your breather tube end up, David? Pete, do you remember where yours did? Inquiring minds want to know!!
__________________
John
96 WTOS 42'
OKC USA!


don't waste your time with a usa-spec ipod adapter- poor products with poor support
Reply With Quote
  #9  
Old 07-02-2010
davidmbrady
Guest
 
Posts: n/a
Default

Hi John,

I'm away from the bus, but I managed to find this photo in my archives; unfortunately, it doesn't show the radiator shrouding, but it does show the breather tube extending to the bottom of the sump pan with a 45deg tip pointing in the wrong direction! LOL Clearly the designer of the tip had front engine applications in mind!


Reply With Quote
  #10  
Old 07-02-2010
fxdwg fxdwg is offline
Senior Member
 
Join Date: Mar 2008
Location: okc
Posts: 3,843
Default

That's a good shot for what I was asking! I'm thinking mine is in the same spot as yours. I wonder if Pete's was in a different location or if there was something else that caused his to oil up more?


I just realized that the end slant may have forced air UP the tube. I wonder if they only did one tube, primarily for forward facing motors?
__________________
John
96 WTOS 42'
OKC USA!


don't waste your time with a usa-spec ipod adapter- poor products with poor support

Last edited by fxdwg; 07-02-2010 at 03:35 PM. Reason: adding info
Reply With Quote
Reply

Bookmarks

Thread Tools

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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
'87 PT38 Sony Stereo Components curtsprenger PARTS OR OTHER ITEMS FOR FREE 4 06-11-2010 04:10 PM
2004 Blue Bird Wanderlodge M380 - Service Brakes, Hydraulic:foundation Components:hos Randy Dupree Vehicle and Equipment Recalls 0 12-17-2007 12:25 PM
2002 Blue Bird Wanderlodge Lxi - Engine And Engine Cooling:engine:diesel Webmaster Vehicle and Equipment Recalls 0 12-16-2007 10:36 PM

Web Search:

All times are GMT -4. The time now is 01:42 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.