Jets, needles & Carburetors again!

Andrew Wiggins

New Member
Hello from semi lockdown Cheshire.

Last Summer I paid to have the HIF6's from my 1973 V8 Auto to be servised / reconditioned. My rational was to start at the top of the engine and work downwards to include SD1 heads and a new cam. (The botton end appears ok and the car is a well looked after honest 43000 miles) This engine has never (apart from the motorway drive back from Holland when I had 24mpg) achieved more the 16 MPG. Last year after the rebuild the offside carb would not tune and I noticed following the fantastic instructions from SydneyRoverP6B in the thread Car now starts but floods - where next? Nov 2015 that the offside carb jet having been lowered would not adjust back up. I complained and the refurb organisation who came out to the car and reported they had found a bur on the jet! This was said to be fixed and the carbs tuned. The car still wasn't running correctly with a lean stall at every junction and and tick over varying wildly with engine temperature and still only 16 mpg. So under lockdown I've decided ( and now know I could have saved myself a load of money) to learn about and fix HIF 6's.

So I have found both jets adjust upwards and beyond the bridge and back down the requisite two turns from level with the bridge, but wont turn all the way back up having gone down! I decided to purchase new jets, jet bearing and at the suggestion of my prefurred parts supplier new BBG (replacing the installed BBV) needles. The new jets are also tight in the new bearings again no significant upwards adjustment, however the new jets in old bearings (and interestingly the new bearings are shorter than the old ) are much more free but the offside is still sticking and would I think be too tight for the bi-metalic spring to adjust. So what do I do?

As an experiment I have polished the old jets with very fine grit paper and they run very smoothly in the new bearings, but the seal between the jet and the bearing is not gas tight, does this need to be gas tight, from what I can see the float bowl is at atmoshpheric pressure so fuel might not be drawn through the bearnig/ jet gap. I don't know so hopefully someone more knowlegable will answer and does it matter that the new bearings are shorter than the originals? I haven't installed the shorter bearings or polished jets just in case.

The disappointment contiues today, so having tuned the carbs (there was enough mixture adjustment for colour tuning) the last 100 miles has achieved the customary 16 mpg. The new needles have sorted the lean stall and I have an in gear tickover of 550 rpm. The SD1 heads and cam project will be next!

Any comments or advice greatfully recieved.

All the best

Andy Wiggins






20160223_130459P6.jpg
 
Andy, I won't presume to offer you carburettor advice, but my compliments, that's one lovely car. Somebody wiser will be along in due course to offer the requisite advice and provide guidance, I'm sure. Persevere!
 
Andy, I won't presume to offer you carburettor advice, but my compliments, that's one lovely car. Somebody wiser will be along in due course to offer the requisite advice and provide guidance, I'm sure. Persevere!
The paint is all down to the previous custodian ( Peter ) in Holland, the polishing and interior is a different story!
 
Very nice! Can I ask whose wheels they are, size and tyres please? Hard to find suitable wheels down here.
 
The wheels are period Cosmics and wear 185/14/90'S. The car has only had four other owners, but I can't tell from the paperwork who or when they were fitted. They're not to everyone's taste but one of the owners liked then so I've kept on the car; I have the original wheels and caps as well.
 
Thanks. Hard to find 5x127 wheels in 14,15,16" here, much less in the correct offset. Will see if any of these are around here.
 
Hi, They look like modern manifestations of the classic style, round holes between the spokes instead of rhomboid ones. Try JBW (John brown wheels) to see if they know of a local supplier.

Colin
 
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