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Andrew_Grannis

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Update 2

Before reading the answers to my last question I tried running the car and it reluctant to start again. With the starting fluid it started right up but had some trouble satying running. My dad was watching the carbs while I was trying to keep it running and when it backfired and shut off, he says it was only from the back carb and sometimes the back fire had gas in it. Any ideas of what this means?
 
Re: Update 2

Lean mixture would be my first guess on the carb that is backfiring.
 
Re: Update 2

Greg,
This may be a silly question but how do I go about changing that if the car wont idle?
 
Re: Update 2

Andrew,
In the BJ8 owner's manual it tells you how to adjust the idle and there is a picture that shows you the mixture screws and idle screws. Read both the owners manual and the shop manual and then try adjusting the mixture then the idle. There is a very good write up in a previous discussion on this forum. You can use the search function to find it , ( upper right side of forum's toolbar under log out ).
I had a problem with backfiring in the rear carb until I replaced the 40 year old Lucas coil. Check the primary side with an ohm meter, it should be close to 3 ohms. I can't remember exactly what the bad coil measured on the primary side but it was significantly different than three ohms, I think mine was 9 to 12 ohms. They can also be internally shorted ( 0 - 1.5 ohms ). To make a long story shorter, a lot of time was spent by my dad adjusting and checking the carbs, especially the rear carb, all because of a bad coil.
Ed
 
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Thank you, I wont be able to get much done with the car today but tomarrow I will get to work on it and tell you how it goes. Andrew
 
Re: Update 2

Hi Andrew,
Is the choke working properly? That may explain why you need the starter fluid at first, but the engine will restart once it has warmed up a little. Could also be why the carb is backfiring when the engine is cold.
 
Re: Update 2

Interesting you ask about the choke. This is because since the engine is from a BJ8 there seems to be no room for the choke assembly to fit so there is a cable for each carb, so it is hard to determine how far to pull each cable. How should I check the choke, try starting the car without it pulled? Andrew
 
Re: Update 2

Hi Andrew,
I’ll preface this by saying I don’t use SU carbs, so I don’t know a heck of a lot about them. If you don’t have the choke cables attached to anything, the chokes are most likely in the “off” position. You would pull the cables away from the carbs to engage it. The first photo shows where the bracket mounts to the firewall and steps the two cables down to one. The second photo is a close-up of my bracket. It looks to me like a 1” or slightly longer pull would fully engage the choke (I can’t test that because my old carbs are seized). If it was me, I’d try pulling both cables out equally about that distance and try starting the motor. The choice is yours. Eventually you should install the entire cable system.
 
Re: Update 2

Thanks, yes both of the cables are attached, they just dont go into a two-into-one bracket as yours do. Id say ive been pullind the cables about an inch so maybe I should try less and see what happens. I want to have the original set up for the choke so I guess i should look into how the mechanism will fit. Thanks alot for your help. Andrew
 
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