[urq] That Pesky Vacuum - Was Helicoil

[AF]

So, thanks to all who offered thoughts on the spark plug helicoil. I had a
track mechanic tap the head and install a steel insert. Worked like a charm
and I was back to driving after installing a new plug and new coil over plug
(which got burned up by the exhaust gasses). 1 session later I was back in
with a misfire, this time in another cylinder in the ABZ. Well, another plug
was finger tight and had lost an electrode or two. I replaced all 8 plugs
just to be sure. I found another 2 that were finger tight. So someone noted
tht lean conditions can result in this kind of damage. Righty-O. Seems that
the sillisest things cause problems.

My gas cap has always leaked gas since doing the engine swap. 2 new caps
later and still no solution. Martin kindly sends me a known good one, and
boy was it a good one.  I started the car, drove 2 miles and head a loud
pop. Thought nothing of it. Drove on the highway and found the car was
occasionally surging and cutting out, but not totally stalling. Seemed like
a fueling issue. Pulled over, pulled the gas cap and I could barely get it
off, the vacuum was so strong. Fast forward 24 hours and I find that the gas
tank has collapsed, at least the top has caved in under vacuum. Seems when 2
bennett did the swap, they did not correctly hook up the tank vacuum line.
It was not vented at all.

So, this might have caused the lean condition...

Questions: Can I pressurize the tank to push it out or is that too
dangerous?

Anyone have a spare tank they'd be willing to sell?

Can someone tell me where the stock tank vent line goes on the UrQ (to the
instake, or a carbon canister?)

Thanks so much.

Andrew Finney
1985 UrQ V8