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Bosch Coil question

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JPSmit

JPSmit

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Friends, today I installed a Bosch Blue Coil - just want to confirm that it has an internal ballast and that, therefore I was right in bypassing the external Ballast Resistor?

Seems to run OK on a short run at least.

thoughts?

PS Top Tip - if you reconnect the Coil BEFORE you start the engine it will start quicker.
 
JP, how well does the engine start if you DON'T reconnect the coil before you START the car?:rolleye:


Kurt
 
JP, you can check the resistance of the primary windings to see if you have the right coil. Hopefully some one who actually keeps track of stuff like that will chime in with the correct resistance readings!:friendly_wink:

Kurt
 
nomad said:
JP, how well does the engine start if you DON'T reconnect the coil before you START the car?:rolleye:


Kurt
Click to expand...

my point exactly. :rolleyes:
 
He probably doesn't know how long it would take yet.
 
Seems to me that internally ballasted coils measure about 3 ohms on the primary side.
 
Last edited:
Bosch Blue coils are considered "standard" or 12V coils. They will typically measure more than 3 Ohms, typically about 4 Ohms. Bosch Red coils are the ones typically used with ballast ignition wiring.
 
dklawson said:
Bosch Blue coils are considered "standard" or 12V coils. They will typically measure more than 3 Ohms, typically about 4 Ohms. Bosch Red coils are the ones typically used with ballast ignition wiring.
Click to expand...

Interesting - I know that Jeff at Advanced Distributers swears by the Blue coils - and sells them though when we last talked he was having trouble getting stock. Apparently there is much conversation about getting a proper one - who knew I figured a coil was a coil was a coil,

https://www.ratwell.com/technical/BlueCoil.html

In other news I had a club BBQ today - was a rainy day (drizzle) so put the top up - got it running (with the coil connected! :grin:smile: only to find the wipers didn't work - so back in the garage it went.
 
I have an old Bosch Blue coil that has bounced from car to car. It just keeps working. It is probably 30 years old (actually says made in Germany ... not Brazil)
 
I have a car needing a coil and I have a Bosch Blue coil in with a pile of other used coil's. Now if I can just remember where that pile of coils are....:rolleyes2:

Kurt
 
quick update - elsewhere there is a post about the car hesitating when hot - took the car out for a couple hours driving yesterday and it performed flawlessly, so, early indicators are that the coil may have been the culprit (as some suggested) - certainly so far so good!
 
JPSmit said:
PS Top Tip - if you reconnect the Coil BEFORE you start the engine it will start quicker.
Click to expand...

Been there. Done that. Part of my "anti-theft" protection when the car was parked outside was to disconnect the battery and the coil. Of course, like any alarm system, you have to deactivate it before you drive it.
 
JPSmit said:
Friends, today I installed a Bosch Blue Coil - just want to confirm that it has an internal ballast and that, therefore I was right in bypassing the external Ballast Resistor?

Seems to run OK on a short run at least.

thoughts?

PS Top Tip - if you reconnect the Coil BEFORE you start the engine it will start quicker.
Click to expand...

To answer your original question : Yes you were correct in bypassing the ballast resistor, at least I have no ballast on my 67 & run a Bosch Blue with a "Jeff" distributor :smile:

Also thanks for the pointer on hooking up the coil before trying to start... good point lol
 
Jer said:
To answer your original question : Yes you were correct in bypassing the ballast resistor, at least I have no ballast on my 67 & run a Bosch Blue with a "Jeff" distributor :smile:

Also thanks for the pointer on hooking up the coil before trying to start... good point lol
Click to expand...

glad to help! I have actually kept the ballast resistor in place just in case - as the old coil has gone into the trunk spares bag - the resistor is bypassed of course.
 
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