HIF 6 AUD521 or AUD623

thob

Member
How can I find out which carbs I got. It's a P6 3500 S from 1973, and the the engine number is 48107614C.
I think the AUD521 is correct but how can I be sure?

I need to get the proper service kit

Thanks
/thomas
 
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There should be a little metal tab with the code embossed in it under one of the three screws holding the dashpots to the carb body.
 
hmm, is there no other way – I'm currently not anywhere near the car? I was wondering if the engine number is telling?
 
There should be a little metal tab with the code embossed in it under one of the three screws holding the dashpots to the carb body.
That’s for HS carbs. For HIF carbs the tags cover the overflow holes on the side of the carb body.
 
They haven’t on the two cars I’ve had with HIF6s. Maybe they were relocated.
 
My parts book says engines up to suffix C use 521; 408 for detoxed; 623 for suffix D (451, 481 series). My RH carb has a tag on a damper screw of 'AUD623L'.
Mine is a 74, suffix D, 481 engine series - which of 2 HIF6 service kits should I get ? Both CSK58 and CSK79 say they are for a pair..?
thanks
 
Hi JP,
I have a Jan 75, 481.... series engine with the same AUD623 carbs.
The AUD623L tag should be on the LHS carb (passenger side, assuming yours is a RHS car).
I bought CSK17 and CSK83 service kits and just recently rebuilt my carbs. The kits were the correct ones for my carbs.

Please note that these kits do not include the spindle, disc and disc screws.
Also, there are separate kits for the left and right carbs as the jets are handed.
Hope this helps.
Paul.
 
checked it today, it's AUD521 and there's a tab embossed with it. Now I'll need to find a kit on the continent
 
When I do the carb kits I will move the tab to the LH carb. RH tab is missing sadly.
 
OK, now started into the first choke assy. The choke locking washing under the nut was not bent over. Notes with AUD623R show 2 orings in the choke, but the Burlen notes from the web say late models had 2 Orings and no gasket . The kit has one O ring that looks correct for the choke body, and a small one that I cant see a home for, so far. There was no gasket on the choke , but one is supplied. Under the end cap of the choke shaft there was a small (~4mm ID) Oring that I cant see being effective - not clamped by the cap, loose on the shaft. Should one of the spindle seals (3 supplied) go in here? Maybe this was the source of the visible small leak, rather than an internal Oring failure, but what was
making it run rich as?
thanks.
 
More. Busted the plastic ball joint thing on the throttle interconnect shaft. Bummer. The old jet had a black base, with a tiny trumpet mouth end facing down; the new jet is white, with the inlet at right angles...??? I measured the location of the old jet at 2.30mm below the bridge, the new one is lower - common occurrence, should I adjust it now? There was a very thin paper gasket on the choke, replaced it. Fitted a spindle seal on the end of the choke shaft. Choke spring - I had some trouble getting the operating plate onto the shaft due to the shaft tending to go in rather than let the plate slide down the shaft flats, and the return action feels OK, but should there be a major struggle to get more than 1 turn on the spring?
EDIT:- WSM says grab the end of the spring and pull around to a tang - looking straight at choke side of carb from inlet face you see a prong/tang - will try to pull spring around to it.
 
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RH carb choke was pretty good, firm fit of spindle, but replaced Oring anyway. Seal at end under cap was an Oring (doing nothing cos it didnt fit anything), replaced with spindle seal - same as on throttle shaft. Spring location seems OK. LH carb - choke spindle was noticeably loose even before loosening screws, and Oring was visibly damaged, a bit flat. Return spring felt soft, and it was not correctly located. despite not running for some weeks now wetness was visible at many joints. Float bowl area was messier than the RH carb. Soon be ready to start refitting, not looking fwd to getting the rear lower nut fitted.
 
bummer, the info on the tab was wrong, and the AUD 521 o-ring etc. don't fit. says my mechanic. Instead I got AUD 3450, it seems. I couldn't find anything in this regard. I checked this catalog to no avail. Any ideas?


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AUD3450 is undoubtedly the casting number for the body & nothing to do with the complete carb assembly which is usually stamped on a tag attached to the body . You wont find any casting number mentioned in the catalogue as only parts you can purchase are listed and when the casting is machined it becomes a machined part number. The only O ring's are on the starter body as far as I know. The V ring seals on the throttle spindle and starter spindle are designed as face seals that get sucked against the spindles and body faces to seal by manifold depression . I am not sure which "O rings etc" you mean when your mechanic states they don't fit?
 
The Burlen booklet (and I think the WSM) mention that 'late' (there's that vague word again!) carbs had 2 Orings in the choke mechanism, and my 623R/L kits came with 1 ~10mm Oring, and a much smaller one, for which I could not find a home. I can see where an internal Oring would seal the choke spindle better than the spindle seal on the outside. Not sure about vacuum sealing the shaft - wouldnt that be sucking extra fuel through ?
 
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