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Hard Starting

dancrim

Jedi Hopeful
Offline
My 65 BJ8 is extremely hard to start when cold. After warmup it starts right up. When cold I mean
at 70 degrees outside. Sputters and dies then finally starts. Installed a hi-torque starter, no help.
Any ideas?
 
I converted to Pertronix and the only hard starting now is below 40 deg. A sport coil may help too. I suspect old cars experiencing cold start issues is a spark energy versus how well the gas has vaporized battle.
 
My 65 BJ8 is extremely hard to start when cold. After warmup it starts right up. When cold I mean
at 70 degrees outside. Sputters and dies then finally starts. Installed a hi-torque starter, no help.
Any ideas?
I also have the same problem when cold or unused for many weeks, I solved with a STARTER spray
The Procedure is this
-Handbrake ON-gearbox in NEUTRAL -STARTER completely PULLED- hood OPENED- Key ON- waiting a little that PUMP works-
then I SPRAY on the two -Air Filters-
and immediately after with the right hand press the Starter Button and
With the Left Hand move the throttle lever(of the carbs) to accelerate a bit - normally starting easy, after few turns
It works for me with the oldest Starter Motor and a Good battery 80 or 100A
Lengthen the Life to all the TWO components
Also my car warmed start immediatly _but require that Gearbox was in NEUTRAL
This is a bug- but I haven't find any explication -Help needed
 
Starting fluid (ether) treats the condition but not the cause, plus it tends to wash lubricant off of the cylinder walls, etc. so use it very sparingly if at all. The problem may be any or all of the following: Bad fuel mixture, weak spark, low compression, or wrong ignition advance.
 
I agree with you
-it is too lean- but car on road is so well- fast and and prompt to run at high rpm- that I prefer this solution-
ether sprayed was in so little quantity (I use it only in the winter starts) that have minor flaws that a burning starter motor or a dead flat battery

https://photos.app.goo.gl/QnicVbqPHEIw6YAf2
 
Sure sounds like a choke problem to me.
 
Sure sounds like a choke problem to me.

Dancrim - you could try pressing down on the choke levers with screwdrivers to see if you can get more travel.

Also, remove the suction chamber domes, springs and carefully remove the piston/needle assemblies. Observe the difference in the main jet depression between the choke off then on positions.

Be sure to not mix up the domes with pistons as they are matched pairs.

With the choke on, the main jet should be down about 1/4". With it off, more like 1/10"

If you're not getting enough choke-lever travel, you may have to remove the air cleaners and loosen the nuts on the levers to allow them to go all the way down.
 
Thanks guys, but the choke travel has been checked. As for mixture, after 500 or so miles the plugs are a perfect light
brown. This car had the same problem before having the SU's rebuilt. No help. Has me stumped.
 
Sure sounds like a choke problem to me.

Yeah:
pull the choke a couple of times before starting and see if this helps, if this helps use the technique or readjust choke pull.

Carbies may be a bit lean also.

Pulling the choke multiple times emulates pumping the accelerator on a modern car
 
Weeellll

I had that problem before I rebuilt the engine and just after. I delved into the Dizzy and found that all was not well in this department. The three legged spring clamping the fixed plate to the moving plate was down to two legs - not good, the third leg had dropped into the bottom of the dizzy, that can not be good, down there with the spring weighs.

On top of that the arm from the vacuum link back to the moving plate is in two sections with a hinge in the middle - the pin had worn badly in fact it was almost grooved right through and the holes were a bit elongated. I used 2mm drill bit to sort the holes out and a piece of a nail that measured 2mm to act as a new pin. In actual fact I have never used the repaired one as I ordered a replacement vacuum unit complete as well as a replacement three legged spring oh, and whilst I was at it a replacement low tension wire, the little one that links the points to the outside world.

BTW as far as I know you can not buy these springs as a new part, all replacements over here are second hand spares. Any way after doing all that and putting it all back together and using my trusty colour tune and timing light courtesy of Mr. Gunson I now have a motor that starts second time on the button - the first time is to prime the carbs, after a spell of standing, and it will tick over at around 750 - 800 revs. regardless of temperature - I need to use the choke to start but after the first start up of the day it is no longer used.

:cheers:

Bob
 
I've had several cars with SU's and find they have excellent cold starting capabilities when the enrichment levers, fast idle and float levels are set properly. Common mistakes some people make: pumping the throttles during cranking does not help, there are no accelerator pumps on SU's; cranking with open throttles also tends to reduce the fuel intake from the main jets. Mine cold starts best with my foot off the gas.

Your SU's sound like the float level is too low or the jets are not dropping down enough to enrich the mixture. It is hard to set the goofy cable linkage on my 100 to depress the jets as much as they need to go to significantly enrich the mixture. Suggest you look here for solutions.

One simple way to check the enrichment: with the engine warmed up, pull out the enrichment knob fully: engine should obviously go rough rich running or even stall. If not, your enrichment system is not set up properly.
 
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