User Login    
 + Register
  • Main navigation
Login
Username:

Password:


Lost Password?

Register now!
Fast Search
Slow Search
Google Ad


[Datsun 1200 encyclopedia]

Altitude Compensator

(Difference between revisions)

Datsun 1200 encyclopedia | Recent changes | Switch to MediaWiki mode

Printable version | Disclaimers | Privacy policy | Current revision

Revision as of 06:54, 14 July 2011
ddgonzal (Talk | contribs)

<- Previous diff
Revision as of 07:16, 14 July 2011
ddgonzal (Talk | contribs)

Next diff ->
Line 3: Line 3:
= Overview = = Overview =
The Altitude Compensator is three types different years: The Altitude Compensator is three types different years:
-* Bellows+* Bellows + hose from air cleaner
-* sensor similar in looks to the A.T.C. and idle compensators+* manual switch - similar in looks to the A.T.C.
-* manual switch+
Same castings with and without the holes drilled: Same castings with and without the holes drilled:
Line 11: Line 10:
== 1976 == == 1976 ==
-It uses a bellows.+It uses a bellows, fitted to the body side. Hose runs from air cleaner to bellows. Then two hoses run to carburetor air bleeds. It is totally automatic.
-[[FSM]] refers to it as an installable option:+Hitachi with 2-hose compensator.
 +<br>[http://datsun1200.com/modules/myalbum/photo.php?lid=23417 http://ddgonzal.members.winisp.net/getThumb.aspx?width=400&uri=http://datsun1200.com/uploads/photos/23417.jpg]
 + 
 +== 1976 ==
 +B210 comes with carburetor fittings plugged. [[FSM]] refers to it as an installable option:
* Drill hole in bottom of air cleaner, insert fitting * Drill hole in bottom of air cleaner, insert fitting
* Run hose over the to Bellows. Mount that on the side of the coil/electronics cover (on strut tower) * Run hose over the to Bellows. Mount that on the side of the coil/electronics cover (on strut tower)
-* Run two small hoses from Bellows to Carburetor+* Run two small hoses from Bellows to Carburetor (remove the plugs)
* Set idle speed and mixture * Set idle speed and mixture
- 
-Hitachi with 2-hose compensator. 
-<br>[http://datsun1200.com/modules/myalbum/photo.php?lid=23417 http://ddgonzal.members.winisp.net/getThumb.aspx?width=400&uri=http://datsun1200.com/uploads/photos/23417.jpg] 
== 1977-1978 == == 1977-1978 ==

Revision as of 07:16, 14 July 2011

Hitachi DCH-306 V-spec carburetors starting with 1976 B210 California models employ an Altitude Compensator mechanism. So the car runs in tune both at sea level and at high elevations -- and everywhere in between.

Contents

Overview

The Altitude Compensator is three types different years:

  • Bellows + hose from air cleaner
  • manual switch - similar in looks to the A.T.C.

Same castings with and without the holes drilled:
23416.jpg

1976

It uses a bellows, fitted to the body side. Hose runs from air cleaner to bellows. Then two hoses run to carburetor air bleeds. It is totally automatic.

Hitachi with 2-hose compensator.
23417.jpg

1976

B210 comes with carburetor fittings plugged. FSM refers to it as an installable option:

  • Drill hole in bottom of air cleaner, insert fitting
  • Run hose over the to Bellows. Mount that on the side of the coil/electronics cover (on strut tower)
  • Run two small hoses from Bellows to Carburetor (remove the plugs)
  • Set idle speed and mixture

1977-1978

California (V) models use a carburetor with two fittings which lead to the air jets. A valve in the air cleaner connects to those via hoses. The valve is manually configurable to either H or L position.

Counties in USA 1,219m (4,000 ft) or more above sea high have been designated "High Altitude Counties" (see 1977 B210 Service Bulletin).

  • At low altitudes: closed
  • At high altitudes: open

Remember to move the switch when you get to a legally-designated HAC -- and then readjust the mixture and idle speed. This is not an automatic system.

1979

Apparently 1979 models did not use a compensator.

1980

Bellows system like 1976 adopted. On above 600 m (1,978 ft). Non-adjustable.

1981-1982

1981 used an Altitude Compensator with totally automatic operation. It works by a bellows moving per altitude, exposing more or less air to the air bleeds inside the carburetor.

  • Operates above 500 m (1641 ft)
  • Adds a third hose, for primary slow air bleed
    • 4-fitting bellows
    • 3-fittng carburetor

Diagram from the 1981 B310 Factory Service Manual
23415.jpg

Hitachi with vacuum secondary and 3-hose compensator.

23418.jpg

23419.jpg