Ian Karr made a nice video on how to replace charcoal in the plastic canister. You don't have to be a masochist to attempt it like you do with the metal can.


https://www.youtube.com/watch?v=6C06XJgLhIc

yes, this is what I used to do mine a few months ago. Easy and fast - guess it needed it after 46 years. Got filler material from local fish aquatic store; more than enough for like $8 or so. Now driving fume-free!

Is the hose sizes correct in the pic below, are they measured OD or ID?
I'm trying to figure out what size and how much hose to buy for three '74 djet systems.

Thanks

edit dang I thought this was the Djet Diagram, but it's 1.8

Yes, O.D. But somewhat approximate - the 4mm lines are actually 4.5mm OD. I’ve updated the figure (see above in thread). Can’t say these are definitive or factory - just what’s on mine.

Here you go Mark, if you choose to use my hose diagram:

Excellent!
Thank you Jeff I have four 2.0 builds to get hose for and two of them are LE's.

@wonkipop - getting more info. Do you know the approx build date of yours (or last four vin numbers. The difference may be a mid- year change.

VINs up on the record list here.

the karmann number is -
0459543 on stamp in the rear trunk
0459543 on the door plate.

think this is right, worked it out once before.
#43, Jan 25th, 74 (a friday car - hopefully wasn't a boozy lunch ).

Ok; here’s the best guesstimate. Counterflow hoses until mid year, then straight thru hoses after that. Or something else.... Still believe the counter flow arrangement would perform the desired capture/release function better, though with a bit more pressure drop.

here is my view.

the 914 is an argument between porsche and vw.
from the get go.

short version -
no one ever knew who had a big hand in styling it. until recently. why?
A. Piech had a big hand in engineering it (i think that is generally accepted and thank god because its brilliant in engineering terms --- BRILLIANT), and in family terms he was in a head butt with F A Porsche in the 1960s. A P had tickets on himself back then - and history has proved why he had those tickets on himself. he was up against the owners son. the son v the cousin. in the end you could say Piech won - but that was at the end of their lives.
On top of that the old dad got screwed in a deal with the incoming VW pres. etc.
all shrouded in mystery until recently because for many years the story could never be told because that would mean reciting a family business deal over the dinner table with Nordoff married to one of the sisters etc that went wrong when he died prematurely.
The poor old 914 is shrouded in family tangles right when its ready to come out.

in short its a car produced with a gentleman's agreement that gets launched over an argument.

the way you resolve an argument is you go.......
you do it your way with your cars and we do it our way with our cars.
and they just split it when it came to emissions set up?
amongst many other agreed compromises.......because its kind of semi-hostile.

VW did it their way in the 4s that came out of the karmann factory in osnabruck from the get go?
thats my "controversial" statement.
and porsche did it their way with the 6s, which were plumbed up at their factory in stuttgart.

even the owners manuals are interesting - they are printed by porsche and not by vw. how reliable is the information in them. are they transmitting info correctly. though we do know that it changes in the emissions warranty from 73 to 74.
and i would not be so quick to dismiss that as a misprint.
because porsche are always in charge of printing the owners manual.
so its going to have their version?
until about the time they change their version?

but the 2.0 L 4s might have been under porsche control. the engine was developed after all by porsche, even though it was a VW basis. i can see evidence they are plumbed the porsche way.

its easy to prove how the 74 1.8s were plumbed when the can was in the engine bay.
i have an original car and i know its right.
and it corresponds to other cars. including yours starbear. and the one sitting around in dr. 914s collection and numerous others.

what i would want to see is a rigorous proof of exactly how the earlier 1.7s and 1.8s are plumbed with the front can. my money is on the VW way. its a hunch. you have to follow the hoses through to the front of the car. and you need an original car to do it with.

history is interesting.

i'm going with the idea that porsche wanted it one way and vw the other.
the big hint is in how 911s were plumbed early on. opposite to VW.


who knows which version actually works the best.
but it is interesting that porsche give up on their version with the 911 and go VW.
whereas VW in all their cars never change their tune.
it could be scientific.
or it could just be german pig headeness?
or neither of them were actually right and the fan blown can was just not such a great idea anyway?

Yeah. Think I’ll do something useful - like have a beer or dinner. On to pulling out the car and cleaning it up for driving!

exactly.

but i did find the answer in the factory workshop manual when i was scratching around in it last week trying to sort out another problem.

occurs in aug 1971 - unrelated to position of the can in front or in engine bay or change in can from metal to plastic.

first 2 years of 4 cylinder cars are plumbed porsche's way (like 911s at that time}.

after aug 1971 4 cylinder cars are plumbed VW's way - or more accurately, 1.7 L cars 72 on.

change is noted by the title of the diagram and by the chronology of how the page numbers are added to the manual as time goes on (sent out as technical bulletin/or revision).
its a trick because when it gets included into the manual as a revision it appears in the page order where the original diagram was. but using the page numbering system you can work out its a later inclusion. i've struck this method before in old professional practice notes i used to get when the world was pre internet. you put in the revised updated note which replaces the earlier note, (with instruction to discard the earlier note) and you move the obsolete material to the back (in the form of a replacement page reprinting older material) which then receives a higher number. it was a procedure that makes you remove outdated material and rearrange the manual with the most up to date material at the front. the clue is in the index to the section. there is no 0.1-1/13 in the index, the index goes up to -1/11. so the earlier 0.1-1/6 gets moved the end and given a higher number past 11. germans!

change in aug 71 is hidden to the casual eye in the cars. still two hoses coming out of the area in the front wheelarch and going to the can.

original schematic 3-D applies when the cars first launched - matches first hose diagram layout for the first 2 years of cars.

update that comes in aug 71 gets very visible after midyear 74 (as you note starbear) when the can goes in the engine bay and the hoses can be seen fully.

gets back to original point.
is the diagram for the hose layout at the start of this thread correct for 74 L jet?
no. it is incorrect.
starbear amended diagram is correct.

of interest to folks with earlier cars, pre aug 71 plumbed the opposite of a post aug 71 originally, but you would hardly notice nor would anyone with better things to do waste time wondering. but its nice to know the hoses are right on a 74

(got rid of the stink out of the can on mine with fun option of long drive on the weekend, purged it - primitive tech kind of works, now see how long it takes to come back!).

above does not answer how 6s are plumbed or 2.0L fours.


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@StarBear

found another 1.8 dr.914 has for sale. story indicates car with intact 1.8 engine bay. hose layout exactly agrees with our original cars.

confirms contrary hose layout of earlier cars to later cars. vapor hose plumbing does not stay consistent from the start of production to the end.

for certain it had changed definitely with the introduction of the plastic can in the engine bay of the 74 1.8s. layout diagrams for 1.8 engine bay can cars suggesting otherwise are incorrect from an historical authenticity point of view.

Click to view attachment Click to view attachment

Ah, more evidence that “we” are unique and special. I think 1.8s may be the rarest of normal production versions.

@StarBear - real special cars buddy.


one day their value will be recognized by collectors the world over.
but not in my lifetime.

Bump