I finally got my SC going....

[G450X]

This forum is great. I always try to "search" a topic I need info on, and chances are on all things 911, it has been asked (and answered) before on this forum.

Well a few months ago I had installed SSI's (only 1 broken exhaust stud), M&K 2 in/out, and new return tubes on my '82 SC. I also performed my first major tune (valve adjustment, oil/filter, plugs - very worn, fuel filter, air filter, plug wires, rotor, ign cap) and all seemed to go well.....

When it first cranked it backfired a bit and then ran very poorly (like on 3-4 cylinders), and I was puzzled. The plugs were very worn, the plug wires looked terrible and had some corrosion in the contacts, the fuel filter looked old, etc. It should have ran like great, and it actually ran pretty good before the tune - even with the worn out components....

I guess I have to blame my stubborness a bit here. I knew the basic trouble shooting principles, and ignored them in my efforts to work alone - to keep the nosey wife out of my shop.... She always wanders around and asks about my numerous parts purchases (that I try to keep somewhat covert), and generally drives me nuts.

I had a spark tester (crude little device) that threw me a bit, I interpreted the faint light as a weak spark and convinced myself that it had a spark issue. I rechecked the valves (what a waste of a bit of Swepco...), and swapped all my parts around a few times, sourced a good used coil & 6 pin CDI (thanks to those Pelicans who helped me source parts), checked all the wiring, etc., etc., with no success. I was depressed and gave up on the SC and worked my BMW for a while to "recover."

In the end, when I finally broke down and asked the wife to help, I uncovered the (simple) mystery. I checked the spark once again with a modern tester and found it to be great! I then pulled the airbox apart to check the CIS plate and found that the pop-off valve had blown itself out off its hole and was sitting in the corner of the airbox! I knew I had a pop-off valve, so the "little" backfire on initial startup did not concern me. What a knucklehead! A bit of careful cleaning up the old glue and some new JB weld, I'm in business. I tried to find the marine stuff JW in Seattle recommended, but could not find it locally (I'm in a semi-small town).

Advice to newbie's like myself - use the search function here, and don't skip a troubleshooting step because you're stubborn and don't want the inquisitive wife in your man cave.... Yes, she asked about (for once not 911 parts!) a tow mirror I picked up for my F250 at the local junkyard (forgot to hide that one), but at least my other girl is running great now....