Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Sluggish Ruby on uphills...
#1
Hi all,
I have a 1937 Ruby Tourer with Zenith 26VA carb.
Where I live, in West Yorkshire, it's all hills, and although the engine's been rebuilt, I have waterless coolant in, timing is perfect and plugs, points, etc., are all OK., it really struggles up hills. (I really mean 'struggle', having to drop to 2nd gear with 2 up).
On levels, no problems at all, and I can easily do 45mph.
I was advised to fit an SU carb, or even a Morris Minor or early Mini one, which I was told would make all the difference.
I have absolutely no idea which, if any, would work best, nor where to look for it.
I also fear that some carbs might be too big to fit under the bonnet.
There's also the question of the  actual fitting to the manifold, and if I would have to locate an adaptor, where would I get one.
ANY advice, or even pointing me in the direction of an A7 carb wallah would be gratly appreciated!
Best, Spoz.
Reply
#2
Please tell us a bit more; has it got four good compressions? Has it got the correct late high compression head? How do you know the timing is right? The ideal SU for easy fitting is the early Morris Minor type (around 1930) which has a fixing flange much the same as the 26VA, but there are also plenty of slightly later ones with vertical fixing holes, but an adaptor plate made from aluminium is easy to devise. When using an old SU make sure it is clean, particularly the dashpot/piston system, and you will have to find the right needle. The later postwar SUs need more work to fit because they rarely have a horizontal body.
Reply
#3
Thanks for your response.
New pistons, rings, etc., tested and all compression good and even across all 4 pots. Yes, have hi compression head.
Timing set by ear and with light...had it set  electronically once when it went for its MOT and it wasn't anywhere as good, so reverted to old method, and it purrs, doesn't snatch, no hunting, and perfect tickover.
Bought but have not fitted Accuspark complete kit, with distributor, and was going to try that.
Basically, I'll do anything to enhance performance and reliability, PROVIDED it's reversible, as I try to use the car as much as possible, weather permitting.
I'm not particularly unhappy, and if it takes me just that bit longer go climb a hill, it's no big shakes, but equally if I can lessen the strain on the engine, it's worth a try...
Reply
#4
It sounds to me as if there is actually very little wrong with your Seven, Spoz.  You have to accept that the Ruby and its tourer derivative were quite heavy cars and with only 17bhp they do not fly up the hills.  They will climb almost any hill as long as long as you are not in a hurry. 
I don't think fitting an SU carb by itself would make much difference.  Some of the earlier 1" versions bolt straight onto the Ruby manifold and don't take up any more room than the standard Zenith, but they are getting very difficult to get hold of.   Ideally you would need to make further modifications to the engine as part of fitting the SU carb.  Things like flattening the camshaft followers and lightening the flywheel slightly are easy to do during an engine build, not so easy afterwards!
The Accuspark ignition system may improve things a bit but I have no experience, try it and see.
Reply
#5
Setting the timing on an Austin Seven is not an exact science and the "sweet spot" varies from car to car. Static timing, using the flywheel marks is OK as a starting point but it's best to do final adjustments on the road. The ideal is to advance just to the point where the crank begins to rumble, and then back it off a tad. This can be difficult to assess with the High Compression head as it does make the engine sound/feel harsh even though it's not. I would have thought that your car, properly set up should be able to take most hills in 3rd gear, apart from really steep stuff.

It may also be worthwhile checking that the auto advance mechanism under the contact breaker is working correctly in your distributor. If it is seized or faulty then you could be running retarded at higher RPM.
Reply


Forum Jump:


Users browsing this thread: 2 Guest(s)