OutoftheBlue

Hello all, this is my first post. I'll do a full hello world post once I get this car running and in my possession.

I have the opportunity purchase a '79 RX7 that has been sitting for approximately 4 years.

After confirming the seals weren't stuck by turning the engine over by hand with some oil poured into the spark plug holes, and replacing the old fuel in the tank with fresh fuel, I tried starting it.

It wouldn't start on it's own, but it would run on starting fluid. After running it for about 3 seconds on starting fluid two times I need noticed the primaries and secondaries were totally flooded. With the key in I could hear the fuel pump running (made a clicking sound which I'm not sure is normal) and saw that fuel was being poured into the secondaries and seemed to be trickling over into the primaries. I knocked on the carb near the floats a little bit and that stopped the flooding so I started it on starting fluid a couple more times and decided to call it quits for the night.

While packing up I noticed there was fuel leaking from the heat shield surrounding the muffler. I unbolted the muffler but the inside of the exhaust pipe where the muffler bolts the mid-pipe was dry. Nothing in the area surrounding the muffler was wet with fuel either.

Is it possible all the fuel the carb dumped into the engine got forced through the exhaust once the engine ran on starting fluid and collected in the muffler without leaving any gas in the mid pipe? As far as I can tell from photos and diagrams there are no fuel lines near the muffler. Is there anything I may have missed?

All help is appreciated.

t_g_farrell

iTrader: (1)

Thats not unusual. Typically happens when a flooded car is started. Get that carb sorted and
you may be in good shape. Sounds likes it got gunk in it. I wouldn't run it anymore until you:

1. Change the fuel filter
2. Blow out the lines as much as possible
3. Get new fresh gas pumping to the carb by having the fuel line disconnected and set in
container. This can also let you measure the flow to make sure its good.
4. Pull the air cleaner and soak the carb with carb cleaner.

I would also recommend dropping the tank and making sure its clean as well as changing
out all the rubber hoses. Since you have a full tank, you may be able to skip that unless
you suspect issues.

You will probably end up having to pull the carb and disassamble to clean the gunk out good.
Rebuild kits are available but don't touch the float settings to change out the needles or seats.
The aftermarket needles and seats tend to stick like the issue you described so maybe
someone did a rebuild recently?

OutoftheBlue

THANKS t_g_farrell!

I rebuilt the carb with the GP Sorensen kit and reused the needles and seats already in the carb. Also cleared out the fuel lines, replaced fuel filter, fresh oil and filter, and waited for the floats to fill up. Turned the key and she fired up instantly.

This is the first time I've driven a rotary, but it seemed like peak power was at around 4k rpms. I expected it to be higher in the rev range, so maybe the secondaries aren't opening? Fair amount of backfiring on deceleration as well, but I expected that with the rotary engine. I turned the idle down from 1k rpms to 750k as per the FSM, but it idles a bit rich e.g. there is black smoke exiting the exhaust.

Planning to take it to Mazda to check compression once I get temp tags, and hopefully I can sort the idle issue out in the meantime.

t_g_farrell

iTrader: (1)

Yeah peak power is around 6k or a little more, will start to fall off around 7k depending on your
setup. Your vacuum secondaries may not be opening. Do a search, there are some threads
about how to deal with it.