engine bay hoses 1.8 L Jet, colors, arrangements etc Options

[wonkipop]

this topic arose in the thread concerning hose colors for D Jet cars.

i've started a new topic so it does not mess the other thread.

first thing to say is that the factory manual is more scant on L-Jet information than for D-Jet. There are no hose schematics with the clarity of the D-Jet layouts for the L-Jet. Secondly some of the information on the L-Jet is misleading.

First thing.

car 1974 1.8.

Green vacuum line from Distributor.
Seems to be the same as the D-Jet cars.

There is a green vacuum (retard) line out of the distributor body to the throttle body.
I think i am right saying its the retard side (sometimes gets dyslexic on that).

The green line in this photo is an original vacuum line. Along with the crankcase vent hose these are the only two lines i did not replace on my car. The crankcase line is moulded to an S - shape and we decided to stay with the original. its still sealing ok.
Same with the distributor line. We checked and still pliable and it was sealing so it stayed. We cleaned it up a little. I also left the intake manifold seals on as we did not go that far in - requires disassembly of the intake manifold. They are still in good sealing condition though looking a little aged.

There is a black vacuum (advance) line out of the distributor to the throttle body.

The green line from the distributor was the only colored line still apparent on my car.

[wonkipop]

yes jeff. (IMG:style_emoticons/default/smile.gif)

i think there was probably a similar kind of technical discussion going on between the two manufacturers as your summary above? otherwise why would they be different and still use the same basic can. the can is a VW part that porsche also used on 911s. a kind of "which way does this thing work best question" - with contrary decisions on final layout.

the more i think about it i believe that 2.0 L cars, being a porsche engineering led engine program to replace the 6, the more i think it 100% logical they stuck with the porsche layout as per your diagram on those particular cars. porsche don't change the 911 until 73 (which is the 74 model year). i believe there is no reason 73 and 74 914 2.0s would not have stuck with the porsche plumbing at porsche's insistence. explains that outlet on the tin on the lhs with a 2.0 engine. something i did not know about until recent thread in other section you pointed out. (i told you i know almost nothing about 2.0s! rarely see another 914 down in aus let alone peer into the engine compartment, only one i ever got to look at closely was my old mates and it was a euro spec crayfords car without any emissions gear).

the factory manuals seem to indicate the smaller base engine cars had the plumbing revised to the VW layout in august 71. (72 MY).


my own opinion is that neither system works well. (IMG:style_emoticons/default/smile.gif) no valve to the atmosphere. just charcoal absorbing (until it is saturated). they are both as deficient as each other? classic VW rudimentary thinking along "passive" lines. a bit like VW's pressurisation of the windscreen washers from the spare tyre? certainly the VW system relies on you driving the car frequently on the open road or freeway at cruise to purge it. otherwise it doesn't work too well at all.

the most interesting historical aspect of it all is that porsche engineering and vw engineering appeared to disagree with each other over such a small item. given that porsche had the "luxury" deal with VW to do a huge amount of their engineering R + D in the 1960s its a sign of what was to become a much bigger argument as soon as h nordoff died?

EDIT

a thought that has come to my mind since doing all that EC research and uncovering the details of the 73 VW emission cheat that was settled behind the scenes was that the EPA might have audited VW thoroughly. its possible they uncovered the differences to the two approaches between Porsche and VW using the same component and questions were asked. the move by porsche to adopt the VW plumbing in the 911 may have been nothing other than a paper work convenience and a bureaucratic decision rather than have the system probed into more closely by the EPA. remembering they were supposed to operate under warranty for 50,000 miles. VW had more at stake than porsche given the numbers of cars that were already on the road. its likely that porsches decision to alter the system had nothing to do with whether their layout worked better than VWs (which it well might have). a case of who had the most corporate muscle in an arm wrestle to get out of an awkward moment with a third party.