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Carb Backfire


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#1 danny19boy86

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Posted 06 July 2015 - 12:25 PM

Just put a 1380 lump in. Got it wire up and plumbed in. Trying to get it started. It won't. The carb keeps backfiring. I'm new to fitting engines by the way. Its got fuel going to carb and there is spark

Edited by danny19boy86, 06 July 2015 - 12:27 PM.


#2 dklawson

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Posted 06 July 2015 - 12:31 PM

There are two main possibilities for carb backfires.  The first is timing.  Did you set the static timing when you put the engine in and if so what timing figure did you use?  The second source for carb backfires is an extremely lean mixture.  Was the carb set up before you put it on the 1380 or was it taken apart and overhauled so the carb settings may be "off"?  

 

Beyond those two main sources of the backfire you could have loose manifolds allowing air to leak in and lean the mixture.  When fitting the distributor you may have put the plug wires on in the wrong orientation.  



#3 danny19boy86

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Posted 06 July 2015 - 01:03 PM

Sorry for if any thing a say sounds stupid but I ain't all clued up on fitting engines. Realizing its a lot harder that I thought. The engine was running in another car before I had it. So I might be wrong but I thought the timing is already set up? The carb was a reconditioned hif44 haven't touched it apart from putting it on.

#4 sonikk4

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Posted 06 July 2015 - 01:05 PM

You say it was running in another car, was it running with the carb fitted or is it one you have fitted??



#5 danny19boy86

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Posted 06 July 2015 - 01:07 PM

It was running in another car but with a Webber carb

#6 sonikk4

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Posted 06 July 2015 - 02:09 PM

Sounds like a carb issue then. That will need setting up and of course the correct needle to suit.



#7 dklawson

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Posted 06 July 2015 - 04:15 PM

And... did you remove the distributor, install the engine, then reinstall the distributor or did you leave the distributor installed while installing the engine.



#8 Mini Manannán

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Posted 06 July 2015 - 04:17 PM

It was running in another car but with a Webber carb


Is this the same Weber carb it was running on before or another Weber carb?

#9 sonikk4

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Posted 06 July 2015 - 04:29 PM

It was running in another car but with a Webber carb


Is this the same Weber carb it was running on before or another Weber carb?

It's a Hif 44

#10 danny19boy86

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Posted 06 July 2015 - 05:01 PM

And... did you remove the distributor, install the engine, then reinstall the distributor or did you leave the distributor installed while installing the engine.

there was no distributor withe the engine. So I used mine of my 998. I guess I shouldn't have

#11 dklawson

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Posted 06 July 2015 - 05:18 PM

The engine should be able to start and run with any Lucas distributor that fits.  However, the advance curve may not be right for driving the car.  It doesn't sound like you have the engine running enough to have driven it at all yet to know.

 

If all you did was install the distributor and you did not set the static timing, the engine is not likely to start.  Are you familiar with carrying out static timing?  Does this distributor have electronic ignition or points?



#12 danny19boy86

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Posted 06 July 2015 - 06:01 PM

Points and I don't know nothing about the timing but I willing to have a go

#13 Stiggytoo

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Posted 06 July 2015 - 06:06 PM

Are your plug leads on in the correct order?



#14 Mini Manannán

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Posted 06 July 2015 - 06:11 PM

 

 

It was running in another car but with a Webber carb


Is this the same Weber carb it was running on before or another Weber carb?

It's a Hif 44

 

 

 

My bad, didn't see that vital nugget.

 

Danny, how did you set up the distributor?  Or did someone set it up for you?



#15 danny19boy86

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Posted 06 July 2015 - 06:22 PM


 

 

It was running in another car but with a Webber carb

Is this the same Weber carb it was running on before or another Weber carb?
It's a Hif 44
 
 
 
My bad, didn't see that vital nugget.
 
Danny, how did you set up the distributor?  Or did someone set it up for you?

1243 clockwise on distributor and 4321 on head




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