Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.
 

Welcome Guest ( Log In | Register )

 
 Reply to this topicStart new topic
> How does this fit into the system: Help with 1.7 D-jet
kpfoten
post Apr 18 2009, 05:01 PM
Post #1


Member
**

Group: Members
Posts: 220
Joined: 15-April 08
From: Escanaba, MI
Member No.: 8,927
Region Association: None
Hi--

My spring project is to put fuel injection back into my '73 1.7. There's a piece that I can't seem to figure out how it fits into the mix--it's on the drivers side and looks like it goes into the fan housing? It's got three inlets. Any help would be great--Thanks!

Here's a pic:



Attached Image
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
swl
post Apr 18 2009, 05:22 PM
Post #2


Senior Member
***

Group: Members
Posts: 1,409
Joined: 7-August 05
From: Kingston,On,Canada
Member No.: 4,550
Region Association: Canada
flash arrestor. The two on the bottom hook to the head vents down by the spark plugs. Top goes to the air filter housing. Part #12 in figure 2.1 of haynes.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
kpfoten
post Apr 18 2009, 05:56 PM
Post #3


Member
**

Group: Members
Posts: 220
Joined: 15-April 08
From: Escanaba, MI
Member No.: 8,927
Region Association: None

Thanks!

QUOTE(swl @ Apr 18 2009, 03:22 PM) *

flash arrestor. The two on the bottom hook to the head vents down by the spark plugs. Top goes to the air filter housing. Part #12 in figure 2.1 of haynes.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
kpfoten
post Apr 18 2009, 06:19 PM
Post #4


Member
**

Group: Members
Posts: 220
Joined: 15-April 08
From: Escanaba, MI
Member No.: 8,927
Region Association: None
Next question: Does anyone have a pic of where on the heads the hose taps into?

I think the P.O. may have jerry-rigged this thing when he put that Weber on--I can't seem to find the hookup, although there's a strange spot on the drivers side next to the intake that looks like it was either booger-welded or JB welded...

Is it important that i have this hooked up?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
dangrouche
post Apr 18 2009, 06:28 PM
Post #5


dangrouche
***

Group: Members
Posts: 550
Joined: 1-May 04
From: San Francisco Bay Area
Member No.: 2,012
Region Association: None
you are correct, there are two stubs of tubing that are adjacent to each intake manifold; both pieces of tubing exit the head, attach to the suppressor that you posted the question on, then finally another hose connects to the top of the air cleaner where these fumes are drawn into to be combusted with regualar air intake air.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
kpfoten
post Apr 18 2009, 06:53 PM
Post #6


Member
**

Group: Members
Posts: 220
Joined: 15-April 08
From: Escanaba, MI
Member No.: 8,927
Region Association: None
Here's a pic of what I've got (Driver and Psgr sides)... Should there be tubes around here?


Attached Image

Attached Image
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
kpfoten
post Apr 18 2009, 07:25 PM
Post #7


Member
**

Group: Members
Posts: 220
Joined: 15-April 08
From: Escanaba, MI
Member No.: 8,927
Region Association: None
(IMG:style_emoticons/default/WTF.gif)

What heads/engine do I have!!? I was told the engine was a 1.7 but it looks like the research I'm doing says that the heads should be vented?

I got pics of what they should look like. ARrgh.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
r_towle
post Apr 18 2009, 07:40 PM
Post #8


Custom Member
***************

Group: Members
Posts: 24,705
Joined: 9-January 03
From: Taxachusetts
Member No.: 124
Region Association: North East States
Those are air injectors for the air pump emmission system.
You dont need to use that t valve.

Rich
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Cap'n Krusty
post Apr 18 2009, 08:18 PM
Post #9


Cap'n Krusty
**********

Group: Members
Posts: 10,794
Joined: 24-June 04
From: Santa Maria, CA
Member No.: 2,246
Region Association: Central California
Those are 1.7 bus heads, '73 or '74. They weren't vented. However, if your oil filler has a PCV valve, you need to vent the heads. Or change the oil filler .............

The Cap'n
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
kpfoten
post Apr 18 2009, 08:52 PM
Post #10


Member
**

Group: Members
Posts: 220
Joined: 15-April 08
From: Escanaba, MI
Member No.: 8,927
Region Association: None
Thanks Cap'n--

I wonder if I have a bus engine? I'd have to check the serial #.

The oil filler looks like it just has a vent but no PCV? Does this make sense?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
swl
post Apr 19 2009, 07:40 AM
Post #11


Senior Member
***

Group: Members
Posts: 1,409
Joined: 7-August 05
From: Kingston,On,Canada
Member No.: 4,550
Region Association: Canada
This is an original 73 1.7 head. Looks different than what you have. The vent is circled. No PCV on a 73.

Attached Image
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Cap'n Krusty
post Apr 19 2009, 09:01 AM
Post #12


Cap'n Krusty
**********

Group: Members
Posts: 10,794
Joined: 24-June 04
From: Santa Maria, CA
Member No.: 2,246
Region Association: Central California
QUOTE(swl @ Apr 19 2009, 06:40 AM) *

This is an original 73 1.7 head. Looks different than what you have. The vent is circled. No PCV on a 73.

Attached Image


"No PCV on a 73"? Of course there is. Any 914 with OE vented heads has a PCV valve. The Cap'n
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
swl
post Apr 19 2009, 10:02 AM
Post #13


Senior Member
***

Group: Members
Posts: 1,409
Joined: 7-August 05
From: Kingston,On,Canada
Member No.: 4,550
Region Association: Canada
What can I say Cap'n? There was never one on my original car - early 73. Certainly they can be removed at any time but my car was pretty new when I bought it. Brad Anders' research seems to support that as factory original.
.
QUOTE
Porsche used a PCV valve on some 1.7L and 2.0L D-Jetronic engines, mostly in the 1973 and 1974 models. Early 1.7L and late (1975 and 1976) 2.0L engines did not have a PCV valve, and the crankcase breather on the oil filler was connected to the air box.

http://members.rennlist.com/pbanders/PCV.htm

Further supported in Haynes.

I do stand corrected though - most 73's would have the PCV.

What would be the technical relationship between the vent on the head and crankcase? The PCV deals with relief of blow by gasses - do those gasses also make their way to the rockers?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
kpfoten
post Apr 19 2009, 10:20 AM
Post #14


Member
**

Group: Members
Posts: 220
Joined: 15-April 08
From: Escanaba, MI
Member No.: 8,927
Region Association: None
Now I'm worried that I have a bus engine...

So what do I need to do? If I have a breather by the oil filler am I okay?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
« Next Oldest · 914World Garage · Next Newest »
 

Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 

Display Mode: Standard · Switch to: Linear+ · Switch to: Outline

Track this topic · Email this topic · Print this topic · Subscribe to this forum

- Lo-Fi Version Time is now: 2nd April 2026 - 01:15 PM
Invision Power Board v9.1.4 © 2026  IPS, Inc.
...
All rights reserved 914World.com © since 2002
914World.com is the fastest growing online 914 community!
We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ...