• Hi Guest!
    If you appreciate British Car Forum and our 25 years of supporting British car enthusiasts with technical and anicdotal information, collected from our thousands of great members, please support us with a low-cost subscription. You can become a supporting member for less than the dues of most car clubs.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

and while I wait for throttle shafts to be delivered...

Share this page

Jer

Jer

Jedi Warrior
Country flag
Offline
Well as all jobs start out, last fall I decided I had to get the seized #3 sparkplug out that had been in there since I got the car in the fall of 2010... plug would not come out, so off comes the head & soak the plug from backside with 50/50 tranny fluid & acetone... does not budge... plan B, set the impact on a low setting, bit my lip & walk the plug out... success & no stripped threads, thread chaser & voila ! Plug threads in perfect & tightens up... notice the carb intake gaskets are non existent, manifold gasket non existent (replaced with generour dollops of high heat orange sealant - yikes !!, carbs had bee painted with silver paint by P.O., broken exhaust stud, corroded cross over coolant pipe, siezed temp sending unit (requiring a new dual gauge), incorrect manifold washers, head washers... and on & on we go as every Spridget job does :smile:
While the carb bodys soak in kleen-flo & the throttle shafts are being delivered I got everything else ready to go, one more weekend of work & I hope to fire er' up ! Everyone loves pictures so here is how the engine bay looks now (not a show car, just a maintained driver) & the rest of the sandblasted & painted bits awaiting installation.
The snow is almost melted !! Bring on the 2013 motoring season !
 

Attachments

  • 4postDSCN8574.jpg
    4postDSCN8574.jpg
    93.5 KB · Views: 159
  • 4postDSCN8576.jpg
    4postDSCN8576.jpg
    87 KB · Views: 148
Sounds like you've been busy. Do you have solid throttle discs or the ones with the poppits?
 
poppits... weird little things, apparently to reduce emissions when letting off throttle or something, think I read that somewhere... it's a 1974 mostly stock, HS2 "549's" on it, think 549 means something, had to use that # when ordering the kit, misread the "master" kit on the Moss site, or I would have already had the throttle shafts..., but then I would have had to order jets separately... meh same diff I suppose. First time rebuilding SU's I have done my share of Quadrajets, Motorcrafts, and even hammering out gaskets for an old updraft carb on my neighbours tractor & an old Holley on a 1948 International dumptruck, have read the"SU Carburettors Tuning Tips and Techniques" book over so I'm not to intimidated... has to be better than they were, by the looks of it it has been a long time (if ever) the carbs had been done... from what I have read usually new throttle shafts are all that's needed, hopefully the housing is okay, throttle shaft was noticeably worn on the one carb in particular... don't want to go down the rebushing road unless I have to !
 
Our size SU's seldom need rebushing. I'm betting the new throttle shafts will do the trick. May want to do in the poppet valve's on the throttle plates. Specially if they look worn. Had a engine swallow one which fortunately didn't do much damage. They do restrict flow though. Common to solder up the holes.

Kurt.
 
Thanks for the advice Kurt, I will inspect the poppets, maybe in my stash I have some throttle plates without the poppets, not sure if I trust my soldering abilities - might be worse off than the poppets being in there !
 
and... she's alive ! New shafts were all that was needed, small coolant leak on thermostat housing (I tried to go without engine sealant on gasket, so much for that plan) aside from that I had to open jets up about 2 flats (from the default 12) & set idle, good enough for now, have to wait for another couple feet of snow to melt, get couple tanks of gas thru it, retourqe head, set valves & then readust carbs. Nice to have all those parts back together & working ! :smile:
 
nomad said:
Our size SU's seldom need rebushing. I'm betting the new throttle shafts will do the trick. May want to do in the poppet valve's on the throttle plates. Specially if they look worn. Had a engine swallow one which fortunately didn't do much damage. They do restrict flow though. Common to solder up the holes.

Kurt.
Click to expand...

Just an update to this helpful point from Kurt, after installing my rebuilt carbs the idle had a mind of it's own, sometimes < 500 rpm, sometimes > 1000 rpm, sometimes just right... I just set the idle a bit higher so it wouldn't stall & put up with it until I had time to pull the carbs & install new throttle plates without the poppets (which I did not have available when I was first informed of this possible issue)-
I had time this past week (& of course was a much quicker job than I had imagined) - WOW what a difference, it's a different car, not only is the idle consistent, it is also smoother acceleration especially on lower throttle (which makes sense as I'm sure the poppets would still have an influence on partial throttle)
So thanks again Kurt & if anyone is rebuilding carbs with the poppets - I would strongly suggest you replace them with normal throttle plates (or solder then up if your adventurous)
 
Well done.
 
You're quite welcome!! Glad you have it running great!

Kurt.
 
Back
Top