My Other Time Sink - SuperHawk Forum

Go Back  SuperHawk Forum > NVT > Everything Else
My Other Time Sink >

My Other Time Sink

Everything Else Anything and everything NON-VTR related
Like Tree1Likes
  • 1 Post By Wolverine

My Other Time Sink

Old 09-23-2017, 08:48 AM
  #1  
Senior Member
SuperBike
Thread Starter
 
xeris's Avatar
 
Join Date: Sep 2010
Location: Bisbee, AZ
Posts: 1,440
xeris is on a distinguished road
My Other Time Sink

In the midst of the fork swap I have spent 5 weeks on a interior trim out of a remodeled 1920's building/now house. Then the S.O. tasks me to fix the daughters beat to $H*t '94 Volvo 940. The daughter, to her credit, did not do the beating.
Mostly simple mechanical stuff, T-belt, water pump, hoses, belts, replace A/C components, etc. The real problem is the heater does not work. Without going into all the details, I have narrowed it down to the HVAC "box" in the dash. Yes I have searched the web for answers and have come up mostly short. One thread that described the exact problem that this car is experiencing, but dead ended without resolution. Believe it was a forum specific to, more or less, this car.
Water is flowing through the heater core. The hoses in and out get hot, but not heat at the vents. My thought is one of the vacuum motors is not opening/closing a door the channel the air through the core. There seems to be a somewhat common problem with the loss of vacuum when the engine is under heavy throttle (is that high or low manifold pressure? Can never keep that straight) causing the the "door" that controls the flow through the core to, well, not control the flow.
I have the recommended fix for the lazy door situation. What I'm wondering is, will this also fix the no heat. I have put my Mighty Vac on the vacuum motor in question with no conclusive results. I would rather not do surgery on the HVAC box if I don't need to.
xeris is offline  
Old 09-23-2017, 03:00 PM
  #2  
Moderator
MotoGP
 
Wolverine's Avatar
 
Join Date: Jul 2007
Location: Gettysburg, Pa
Posts: 4,384
Wolverine is on a distinguished road
That repair sucks *****!! Can't help but hope you don't have to pull the core.
xeris likes this.
Wolverine is offline  
Old 09-24-2017, 06:23 AM
  #3  
Senior Member
SuperBike
Thread Starter
 
xeris's Avatar
 
Join Date: Sep 2010
Location: Bisbee, AZ
Posts: 1,440
xeris is on a distinguished road
Originally Posted by Wolverine View Post
That repair sucks *****!! Can't help but hope you don't have to pull the core.
You are so right. I don't think I have it in me to pull the dash. Hopefully the work around hack will fix it.
xeris is offline  
Old 09-24-2017, 10:38 PM
  #4  
Senior Member
MotoGP
 
smokinjoe73's Avatar
 
Join Date: Jul 2007
Location: NYC
Posts: 4,872
smokinjoe73 is on a distinguished road
Is it a vacuum hose used to control the HVAC? In my van I had a similar issue but it was all perished vac lines which of course didn't hold vac. I got a diagram and replaced a bunch of rubber tubes and it worked fine.

Did you join the Volvo model forum? Someone has solved this issue and will help.
smokinjoe73 is offline  
Old 09-25-2017, 06:19 AM
  #5  
Senior Member
Back Marker
 
Pidge's Avatar
 
Join Date: Jan 2014
Location: Malden MA
Posts: 160
Pidge is on a distinguished road
Vacuum Sucks

Look for a check valve in the vacuum line to the damper controls. They can get gummed up and not hold. Especially if there is a leak downstream and lots of air is flowing when it should not be. It is there so whatever the vacuum is controlling stays in the desired position when you give the engine lots of throttle and the manifold vacuum level drops. They are usually made of plastic and about the size of a quarter. Carb cleaner spray will usually clean them out.
Pidge is offline  
Old 09-25-2017, 06:35 AM
  #6  
Senior Member
MotoGP
 
smokinjoe73's Avatar
 
Join Date: Jul 2007
Location: NYC
Posts: 4,872
smokinjoe73 is on a distinguished road
Oh yeah check valve. Replace that for like$1.50 and look at the vacuum accumulator or ball. Holds the vacuum during those uphill climbs.

Good to hear the universe opposes all fork swaps and not just mine. Took me 2 years of other repairs to get to mine.

Last edited by smokinjoe73; 09-25-2017 at 09:04 AM.
smokinjoe73 is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
crtlv
General Discussion
15
07-07-2010 01:00 AM
nativegolf
Modifications - Performance
31
05-20-2007 12:59 AM
Texassuperhawk
Classifieds
9
05-08-2007 01:42 PM
EngineNoO9
General Discussion
0
03-16-2007 06:26 PM
seattlesucks
General Discussion
29
03-07-2007 08:46 PM


Thread Tools
Search this Thread
Quick Reply: My Other Time Sink


Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.