1981 Fiat Spider won't start

[rlux4]

Thanks for the update. Too many times we never hear back when a problem is solved, so never know what the problem was.
Ron

[rjkoop]

Weird. Tried to do the seafoam thing tonight and when I disconnect the brake booster line the car stalls even if my son tries to keep it at 2000rpm. Any thoughts?

Here's what looks like the brake booster line (coming from the brake booster unit) - the frayed large black line...



The connector on the right...

[rlux4]

That gives you a massive vacuum leak which will definitely stall the car. Our L-Jetronic system does not like vacuum leaks, it's extra air in the fuel/air ratio that the ECU isn't taking into account.
To get a better understanding of the basics of how the system works you can download Brad Artigue's Fiat Maintenance and Modification manual. Look for the section on fuel injection.
http://www.artigue.com/wp-content/uploa ... 124_MM.pdf
Ron

[giuliot60]

Congrats. I've just bought an 81 in the spring and did the Seafoam treatment through the brake booster hose. You have to keep it plugged then open it enough to suck the Seafoam into it. I think I used a funnel, or just kept my thumb over the opening. I'm already getting a little fuzzy about how I actually did it and it was only a couple of months ago. But I remember it wasn't too hard to resolve. Just pre-measure the amount you want to use.

I bought a gallon of Seafoam and throw some into the tank every once in a while as well. Great stuff.

I would also do as much of this as possible: http://www.mirafiori.com/faq/content/el ... estore.htm

This is a great site.

Good luck.

[rjkoop]

Thanks. I'll try that. When I had the brake booster line disconnected and start it I noticed a backfire (spark) coming out of the vacuum hose. I guess this was because of the extra gas pumped in when starting. I think I'll try starting, disconnecting and then covering the hose with the thumb (with gloves I guess!). Then I'll slowly add and cover with thumb as I add a bit.

[4uall]

if memory serves me correctly I think I had the car started then removed the brake booster, used a small funnel then slowly added the sea foam. let it sit for 10 min, then start up and run her/drive her for a bit until white smoke was gone.

[rlux4]

As a precaution you should check your valve timing and clearances before you do much driving. If you're getting backfire in the intake plenum and the brake booster line is connected the escape for that pressure is back through the air flow meter which can damage the flap. A little trick to limit that possibility is to leave the boot connection at the AFM slightly loose and it will blow off instead of the pressure being forced backwards through the flap.
Ron