type 4 heads
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[email protected]
- Posts: 1
- Joined: Fri Mar 17, 2023 2:59 am
type 4 heads
my 1972 bus 1700 has what looks like a breather nipple coming directly out of the upper left side. What is it and if a hose should be attached, where does it go to or come from. Any help thanks!
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Clatter
- Posts: 2046
- Joined: Sun Apr 28, 2002 1:01 am
Re: type 4 heads
This is a deep subject.
Look at the part numbers on the heads.
Pretty sure those are going to be 914 heads.
The 914 had a fairly involved breather setup that worked in conjunction with D-Jet FI.
Many using carbs will route them to a breather box.
Really nice to have vs. venting valve covers.
What's your setup?
Look at the part numbers on the heads.
Pretty sure those are going to be 914 heads.
The 914 had a fairly involved breather setup that worked in conjunction with D-Jet FI.
Many using carbs will route them to a breather box.
Really nice to have vs. venting valve covers.
What's your setup?
Speedier than a Fasting Bullet!
Beginners' how-to Type 4 build thread ---> http://shoptalkforums.com/viewtopic.php?f=1&t=145853
Beginners' how-to Type 4 build thread ---> http://shoptalkforums.com/viewtopic.php?f=1&t=145853
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Ephry73
- Posts: 3369
- Joined: Fri Mar 02, 2001 12:01 am
Re: type 4 heads
Should go to a T or catch can that is siphoned out to the air filter. I had a similar setup which I piped to old school 912 air filters. Never had an issue. Oil breather and catch can is never a bad idea for our motors.
E
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E
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vanapplebomb
- Posts: 25
- Joined: Wed Sep 04, 2013 1:17 pm
Re: type 4 heads
Those heads are from a 1.7 Djet engine, either out of a 411 or 914.
The nipples are for the engines fresh air intake for the PCV system. Only the Djet model type 4 engines have the PCV system.
They were teed together on a backfire valve and plumbed to the clean air side of the air filter. The PCV valve was plumbed to manifold vacuum at the plenum.
The nipples serve no purpose for carbureted engines. If you engine has a lot of blow by ( which it shouldn’t) you could treat them as a crankcase vent…
If you have the Djet heads, check and see if someone used the Djet breather with the PCV valve. If so, remove the valve and replace it with a nipple, then plumb it to the dirty side of the air cleaner.
The nipples are for the engines fresh air intake for the PCV system. Only the Djet model type 4 engines have the PCV system.
They were teed together on a backfire valve and plumbed to the clean air side of the air filter. The PCV valve was plumbed to manifold vacuum at the plenum.
The nipples serve no purpose for carbureted engines. If you engine has a lot of blow by ( which it shouldn’t) you could treat them as a crankcase vent…
If you have the Djet heads, check and see if someone used the Djet breather with the PCV valve. If so, remove the valve and replace it with a nipple, then plumb it to the dirty side of the air cleaner.