ZaqAtaq

I am looking to purchase a 93 RX7 from a guy I work with. The abbreviated history: He is the second owner, bought it with 40k miles on it in 96ish, had the engine rebuilt, turbos rebuilt, clutch replaced at 48k miles in 99-2000 (paperwork to prove it). Got a coolant leak with 62k miles on it so he parked it in 2006ish and never got around to fixing it. He tops it off once a month, takes it on a 2-3 mile drive at which time it is heated up and begins to leak coolant so he pulls it back into the garage until the next month.

I went and inspected it today following this buyers guide: Buying a Used RX-7

Coolant looks good, no sign of oil. Oil dipstick looked good, no sign of coolant, however it does smell a bit like gas (maybe this is normal). Hooked up a boost gauge and went for a drive, got the 10-8-10 (though the 10 was closer to 12 a couple times). Warmed up, idle was good. Pulled back into his driveway and the coolant leak was BARELY there but it was burning coolant as there was white smoke and sweet smell coming from the area where the turbos are. Leak was not obvious enough for me to find it so I moved on to the compression test. Taking out the bottom spark plugs with the engine warm is less than fun but I managed and here are the videos of each of those:

Rear:

Front:

Once it cooled a little I stuck a radiator pressure tester on the coolant system and pumped it up to 15-20psi to look for the leak. Got a steady stream BUT it was from the front; upon further investigation it was coming from the vent on top of the overflow tank. Absolutely no leak present at the turbo like the owner says it usually comes from (by the turbo, the location the smoke came from).

My questions are: The compression seems a touch on the low side; around between 80 and 90. Am I just being picky or does it look acceptable?

What the heck could the smoke be? Coolant line going to the turbo? Coolant seal in the turbo?

And finally, when we started it back up after the compression checks, there was a rattle for about 15 seconds. Touch the gas and it went away until we shut it off and started it back up, same rattle for 15 seconds. Sounded like exhaust heat shield to me, which I understand can be an issue, but seems weird it happened for the first time after I was digging into stuff. Any thoughts on this?

Thanks in advance for the help!

Sgtblue

iTrader: (16)

*Compression seems low to me too. How does it hot start?

*My first suspect would be the turbo coolant hoses. But there are other possibilities.

ZaqAtaq

Hot start was fine. No white smoke even on cold start or heavy acceleration. I also suspected coolant hose but not being able to produce it using the pressure tester confused and concerned me. What are my other options for tracking it down? My ultimate goal with it is to drive it a few months and flip it so I do not want to get into an endless project like I would be willing to take on if I was keeping it.