Dauntless V6 Heat Control Value - Off-Road Forums & Discussion Groups
Go Back   Off-Road Forums & Discussion Groups > Jeep > Jeepster-American Jeepster Club

Jeepster-American Jeepster Club Please also visit our club web site for more information at http://www.americanjeepsterclub.org/



Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 12-15-2005, 06:23 PM
Stranger
 
Join Date: Aug 2004
Location: Grass Valley CA
Posts: 15
Thanks: 0
Thanked 0 Times in 0 Posts
katn is an unknown quantity at this point
Default Dauntless V6 Heat Control Value

Just replaced the exhaust system from the manifolds to tail pipes. Yes pipes. I went with a dual system, with pipes out the side instead of the rear. I think it's sweet.

While we did the install, it was found that the heat control value was stuck in the closed position. So it was just cut out. No wonder the engine ran HOT!

So the questions of the day is: Should I find a replacement, and where do I find it? Or do I go my merry way without it, but spend some more time warming up the beast before heading out on the road?
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old 12-15-2005, 11:09 PM
chdorsey's Avatar
Can't Get Enough
 
Join Date: May 2002
Location: Winchester, VA
Posts: 1,364
Thanks: 0
Thanked 0 Times in 0 Posts
chdorsey is an unknown quantity at this point
Default Re: Dauntless V6 Heat Control Value

When you say heat control valve, do you mean the piece that bolts to the pipes at the flange at the manifold? If so, I believe that is actually the control for the automatic choke for the carb.

Chris
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #3  
Old 12-15-2005, 11:23 PM
Way Outta Control
 
Join Date: Sep 1999
Location: usa
Posts: 10,815
Thanks: 0
Thanked 1 Time in 1 Post
RRich is an unknown quantity at this point
Default Re: Dauntless V6 Heat Control Value

Heat riser - closed it directs the exhaust on that side to go up through the intake manifold to the other side, thus heating the carb.

It'll be harder to warm up now. Just let it warm up a little longer.

But you'll notice performamnce and mileage are improved by a bunch!
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #4  
Old 12-16-2005, 03:13 PM
Tyrone Corn's Avatar
Enthusiast
 
Join Date: Mar 2003
Location: Southwest Idaho
Posts: 339
Thanks: 0
Thanked 0 Times in 0 Posts
Tyrone Corn is an unknown quantity at this point
Default Re: Dauntless V6 Heat Control Value

When I installed headers a few years ago, I discovered that my valve was frozen shut also. Made me wonder how it ran as well as it did. At any rate, it was eliminated with no ill effects.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #5  
Old 12-16-2005, 03:31 PM
badbrad's Avatar
Old Hand
 
Join Date: Aug 2002
Location: Chester County(SE), Pa.
Posts: 1,179
Thanks: 0
Thanked 0 Times in 0 Posts
badbrad is an unknown quantity at this point
Default Re: Dauntless V6 Heat Control Value

RRich,

Wasn't there also a post about plugging up the crossover passages you described? Of course that requires the engine to be apart.

Brad.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #6  
Old 12-17-2005, 01:46 AM
Way Outta Control
 
Join Date: Sep 1999
Location: usa
Posts: 10,815
Thanks: 0
Thanked 1 Time in 1 Post
RRich is an unknown quantity at this point
Default Re: Dauntless V6 Heat Control Value

Plugging the crossover would make it act even colder, even in moderate weather. Plus, it'd be a pain.

But you might remember a problem associated with it. Unlike newer engines, the 225 used the old style of carb heating. The crossover came up, right out of the manifold to the bottom of the carb, passed through a passage underneath the carb, then back down to the other side. That often burned the carb base and/or gasket, allowing exhaust gasses back into the intake == instant EGR, and too much.
The cure for that was just plug off the 2 holes under the carb.
But that still allowed hot exhaust gasses to heat the intake manifold some.

Remember, the carb is evaporating gasoline - gas has a low dew point. The evaporation/atomizing process removes heat - the carb can ice up even on hot days from the evaporation.
That's why it needs a little heat.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #7  
Old 12-18-2005, 09:14 AM
chdorsey's Avatar
Can't Get Enough
 
Join Date: May 2002
Location: Winchester, VA
Posts: 1,364
Thanks: 0
Thanked 0 Times in 0 Posts
chdorsey is an unknown quantity at this point
Default Re: Dauntless V6 Heat Control Value

Okay, I am probably going to get the exhaust bent up on mine pretty soon. Should I keep that valve in there or toss it? If I toss it, is there anything I need to plug up or do as a result? Thanks,

Chris
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #8  
Old 12-18-2005, 09:32 AM
Way Outta Control
 
Join Date: Sep 1999
Location: usa
Posts: 10,815
Thanks: 0
Thanked 1 Time in 1 Post
RRich is an unknown quantity at this point
Default Re: Dauntless V6 Heat Control Value

As long as it's still working I'd keep it.

It has to move freely, and the bi-metal spring has to still be OK.

When it's cold the spring closes the flap, redirecting some of the exhaust. If exhaust pressure increases much, then the force of the exhaust against the spring and counterweight opens it so it's not restrictive. When the spring gets warm, it stops trying to close it.
You can bench test it - at room temp and at the normal angle it should be closed. Play a propane torch or heat gun on the spring a moment, it should open up. DON'T OVERHEAT THE SPRING! The torch can easily ruin it.

Removing it presents a little problem - the top is a flange that bolts to the manifold, yet the bottom side the pipe attaches with a flared type connection. If you are building a new exhaust it's not a problem, but just removing it from a stock system you need to convert the connection.

Mine froze up in the partlialy closed position, too far gone to save it. I cut out what was left of the butterfly and removed the remainder of the shaft. That left 2 small holes where the shaft had been to weld closed. Easy.

If you are in a very cold area, you might want to consider keeping it.

By the way - muffler shops have brass nuts - they won't rust to the steel studs. Be careful the way you ask for them though.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #9  
Old 12-18-2005, 11:19 AM
chdorsey's Avatar
Can't Get Enough
 
Join Date: May 2002
Location: Winchester, VA
Posts: 1,364
Thanks: 0
Thanked 0 Times in 0 Posts
chdorsey is an unknown quantity at this point
Default Re: Dauntless V6 Heat Control Value

[ QUOTE ]

By the way - muffler shops have brass nuts - they won't rust to the steel studs. Be careful the way you ask for them though.

[/ QUOTE ]

LOL. I will keep that in mind. I already have the system apart and the valve seems to be flexing pretty freely. I'll hit it very briefly with a torch and see if it responds. Thanks for the help.

Chris
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Sponsored Links
Advertisement
 
Reply

Thread Tools
Display Modes

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
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -5. The time now is 11:02 PM.


Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO 3.2.0
Copyright 1994-2009, VerticalScope Inc. // Off Road forums & discussion groups sitemap
side by side | atv | dirtbike | snowmobile | sandsport | competition | land use | Jeep | Toyota | Ford | GM