Ok, deep into this engine bay. Removed TB for rebuild but can’t figure out how to disconnect cable from the TB. Looks (?) like an Allen bolt from underneath but the hole is circular so wrench doesn’t bite. Pics below.
The cable was replaced a few years ago, by a local garage as was stranded roadside on a Sunday morning.
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allen wrench in the middle to loosen it.

Will try again.

Tried 3.5mm which moved but didn’t turn the bolt. The 4mm wrench didn’t seem to fit as too large.
Soaking in squats of PB blaster.

I'm curious- Is that an early TB or something other than a 2.0? The throttle cable on my '75 and '74 2.0 TBs are attached differently.

74 1.8L L-Jet FI. Have seen others with a barrel and hex bolt. Much more sensible. Our 1.8s are quirky little rascals, eh @wonkipop ?

Got it, with help from @Bartlett 914 . Set screw from top; hole was a bit distorted. Used small vise grips to unscrew from top, careful not to crush threads. Came right out (maybe some help from overnight PB Blaster soaking. Whew!
Off to rebuild (the TB, not me, but a close decision….)

If the hex is rounded out try a torx bit in the hole. You may have to squeeze it into get a good bite. Those small allen screws strip easily.

My 74 1.8 is a 8mm hex bolt that retains the throttle cable end. Interesting that yours is an allen grub screw. If the metric doesn't fit try an SAE allen key.

Perfect! Have a small torx bit that fits perfectly all set up ready when to reinstall. Great tip! (Pun intended)

A much better arrangement. Easier and less trouble. Probably changed to that setup over the years. That’s the assembly now being used/sold. Mines original but maybe changed design as time went on.

Looks like in the 914 parts catalogue it shows the barrel nut and a hex head bolt from factory. M5x10mm length bolt. My guess is someone may have swapped that out at some point in its life.

Yeah, maybe. Will research. Might change out to that better design. Will check PET, too.

mine is the same as yours i believe looking at your photo.
original set up?

trying to remember if i had trouble with mine 3/4 years ago.
don't think so.
sounds like you got it out ok.

where you getting your throttle body rebuilt?

@StarBear -

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yep - same as mine.
i need to blow the grime out with carb cleaner.

from the factory manual.

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the set up @L-Jet914 mentions in his post as listed in the PET is for 914/4, 1.7 and 2.0.
not noted as for 1.8
does not list a 1.8 set up as far as i could tell.
the whole throttle body bit and illustrations for the 1.8 set up are a bit hazy in the PET and have to be read closely. but i can't find specific mention of what it is listed.
however what we have does co-incide with what is shown in factory workshop manual for L-Jet 1.8.

i have never replaced throttle cable on mine.
its been there since 1989.
can't speak for before that.
also i did have it off 3/4 years ago to clean throttle body and TPS etc and it did not give me any grief as i recall. i did it with the allen key wrench as shown in workshop manual.
after blowing the gunk out of it.

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where you getting your throttle body rebuilt?
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@wonkipop
By @Bartlett 914. In Illinois here stateside. Shipped it out yesterday.

Ha! Our 1.8L quirkiness strikes again! We’re SO special….
Will have to carry my small torx with me in the car, or straighten out the hex hole to fit the correct wrench. Looks maybe like a 3.5mm, which I carry in car- for the headlights or something.

@L-Jet914
@wonkipop
Took LJet’s suggestion and tried SAE Allen wrench. 3/32 worked perfectly.
Why SAE in metric car? Different supplier? Changed out when cable replaced a few years ago? Strange.

i would guess that your grub screw and pivot were replaced in incident you mentioned in earlier post with a very similar fixing that was USA (imperial) sized. i'm thinking the little grub screw throttle cable fixing is a reasonably common fixing available both in metric and imperial sizes. or they lost the grub screw and put another one in with correct thread but an imperial sized hex for the allen key.

all i can say about mine is i have only metric allen keys so i'm thinking mine must still be metric or i would not have gotten it off 3 or 4 years ago. i think @L-Jet914 is correct.
someone maybe replaced yours like for like but imperial sized.

everything in writing in both PET and factory workshop manual describes the fitting as a fillester screw. ie a conventional screw with a head on it. which i'm guessing all the other 914 variations have. we have a grub screw fitting and there is only one place it is shown as an illustration, but there is no listing of it saying/listing what it is. a typical little detail that slipped through the proof check on the factory manual and the PET catalogue.

at least a 914 is not like an aussie ford. australia converted to metric in 1974 (same year as my 914). but they were still making aussie fords with many imperial size bolts and fixings in them nearly all the way to the end of manufacturing here. the falcon ute (1994 model) i restored was exasperating as it was a mixture of imperial and metric depending on what component you were trying to take off or take apart. nuts. luckily mike has a full compliment of tools in both metric and imperial. i have no imperial tools.

@wonkipop
IF I get adventurous and try for a correct metric screw, what is the correct size - 3mm? 3.5mm? What’s yours?

i've left my big toolbox down the workshop with the allen keys in it.
you will have to wait until i bring it home to investigate.

Ok. Looks like the screw is 4mm diameter and 6mm long. That might leave the hex key size maybe 2.5mm?

i went across the lane and borrowed my mate pete's allen key set.
they were all loose in a box and no sizes marked. but all metric.
but i got a perfect snug fit and i reckon its a 3mm.
it could be 2.5mm.
i put it on my steel ruler and looked at it under the magnifying glass.

(my allen keys are all loose and unmarked too, just pick em up and see which one fits, but its definitely a perfect snug fit with a metric allen key.).

Awesome! I have complete set with both sizes. Onward!

go with a 3 if you can pick up the grub screw with the size to fit.
its got a bit more grunt as an allen key when you are tightening it i reckon.

@wonkipop
@Big Len
@L-Jet914
@Van B

Ok; tried a few at local hardware store. For those of us with minutia interest and 1.8L historians, here’s what seems to be the spec for the set/grub screw:

5mm x 6mm @0.8 pitch with 2.5mm Allen wrench.

(the 3mm wrench was a tad too big. Might put just a drop of lock-tite on the set screw just to be sure. )
Onward!

That's not an 8mm bolt. It has an 8mm head. I think the bolt the 3mm.

good detective work starbear.

i'll reference that away.
it 99% likely is a 2.5mm allen wrench. i was measuring the end of the wrench that fitted the grub screw with a steel ruler. not exactly a micrometer. if i took it down the workshop i could probably have got the exact size wrench.

You're right. I should have mentioned that the head was 8mm.

I stand corrected. I thought I had an 8mm head bolt. Someone at some point must have replaced the allen key grub screw with a flat head screw at some point in its life.

@L-Jet914
Perfect time to correct things! Got the correct one at my local hardware store. 35c each! 2.5mm Allen wrench was 75c!

I need to replace my throttle cable on my 1974 1.8L-jet as it is binding. I tried to loosen the grub screw (2.5mm hex allen head) but it got stripped and I gave up. This interesting thread caught my attention will try the torx wrench suggestion.

@StarBear @L-Jet914 ( @tshih914 )

i might have solved the mystery of where the grub screw is listed.
i was thinking about L-Jets question about fuel line grommets and the dreaded 1.8V designation.

so i dug up my copy of the european PET catalogue with the full listing for the twin carb version parts.
sure enough its there.
thats why its got the weirdo throttle cable connection that confirms StarBears scientific view that 1.8s are so special.
they used the parts they were using on the twin carb cars.
but forgot to hep out their special american owners half a century down the track.

here is what it is. appears to match exactly what he have.
so now we know. AM5x6mm grub screw.

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Last choice

Well I'm literally screwed I tried the T10 torx bit and still didn't budge so when I tried the vice grip it broke off the upper lip so now I'm forced to drill it out and it appears to be quite tough (titanium bit not hard enough.) Will try to get some cobalt drill bits.

Ouch. Best wishes!

The screw is already buggered.
Jam the allen or torx into the socket and weld it into place. Someone may have put loctite on it (badness!!!) and the heat will break it loose. Turn it out and replace as needed.

Replace with a bolt you can put a wrench on Those tiny allen sockets strip out way too easy.

Zach