Test Start

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David Jones
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Re: Test Start

#16 Post by David Jones »

Backfiring through the carbs is usually mixture too lean caused by an air leak or worn carbs or mixture screws too far in or idle jets too small. That is a just the possible carb issues.
If I had known I would live this long I would have pushed the envelope a little harder.
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Bill Lawless
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Re: Test Start

#17 Post by Bill Lawless »

David Jones wrote:Backfiring through the carbs is usually mixture too lean caused by an air leak or worn carbs or mixture screws too far in or idle jets too small. That is a just the possible carb issues.
Thanks David, I do get an occasional backfire up through the carb.. I will check for leaks and such..
But what I see more is when I run the RPM's up and drop it, it will backfire through the exhaust.. Found out my timing light is not working so the timing could be off a bit.

Bill
 Thanks,
Bill
65' 356 SC Cab Irish Green :D
82' SC Targa
81 VW Westfalia with 2015 Forester Engine
BMW 64'-R50/2, 75'-BMW R90/6, 74' BMW R90/6, Yamaha BW350

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Martin Benade
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Re: Test Start

#18 Post by Martin Benade »

That is usually due to exhaust leaks.
Cleveland Ohio
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Mark Sabbann
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Re: Test Start

#19 Post by Mark Sabbann »

Bill Lawless wrote:Actually I just need a Solex fine tuning guide, never had Solex before.
This may get you started: https://porsche356registry.org/article/47
Mark Sabbann
1964 SC Coupe 'Essy'
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Doug McDonnell
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Re: Test Start

#20 Post by Doug McDonnell »

Float level should be towards lower level of gauge due to panther piss sold today. Back firing or spitting back through carbs? My late friend Bill had a fresh rebuild of S90 that kept spitting back through carbs and poor idle he could never get right. Solved by distributor rebuild.
1965 356C 2000 BMW 740i Sport 1967 Honda CL77 There is never enough time to do it right, but always enough time to do it over.

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Bill Lawless
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Re: Test Start

#21 Post by Bill Lawless »

I think I got it, Doug's suggestion of lowing the Float level helped a lot. And I wacked my timing light with the back of my hand and it started working..
Idles smooth, revs right up, timing is advancing.... And no more backfiring. Yeah!!!

Lesson Learned!!! If you buy a used engine and they say it's know to be running see it run first..

Now back to restoring the car it's going in, Then re-build the original engine.. No lack of fun here..

Thanks for all the words of wisdom...

Bill
 Thanks,
Bill
65' 356 SC Cab Irish Green :D
82' SC Targa
81 VW Westfalia with 2015 Forester Engine
BMW 64'-R50/2, 75'-BMW R90/6, 74' BMW R90/6, Yamaha BW350

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Doug McDonnell
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Re: Test Start

#22 Post by Doug McDonnell »

All right all right all right. https://www.youtube.com/watch?v=FKO9CCfc3Tw
1965 356C 2000 BMW 740i Sport 1967 Honda CL77 There is never enough time to do it right, but always enough time to do it over.

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