brey

I have a 85 RX-7 I drive daily. Today my slave cylinder for my cluch went out while I was going down the road. No biggy, I rebuilt it on the side of the road but when I went to crank my car the motor was locked. I put it I gear and rocked it till the engine finally turned over. It cranked but it runs like crap. It backfires bad and wont run much faster than 45 MPH. I added oil to it while it was running ( it was about a half qt low), and it smoked up the whole parking lot I was in. I drove it for about 11 miles and the oil pressure and water temp was normal.It didn't smoke except a few seconds after I added the oil. The engine could have been vapor locked but I don't know if a rotary will vapor lock. all I know is the starter would not turn it over and when I tried to push it off it would leave black marks on the road from jumping the cluch in 1st gear. I finally got the engine to turn over but it still don't run right. The only mods I have now are headers, msd, k&n, plugs & wires. I can crank it now but I wont run like it should. This is the only transportation I have right now except my bike and it is a little cold for that right now. please help.

BRealistic

Carbon lock?

brey

What causes carbon lock? Is it just deposits from cheap gas, and why did my 7 go from running so smooth to running like doodoo in just the matter of mins.?

BRealistic

Well- carbon builds up on the rotors over time (unburnt gas and oil)- and can flake off. I was just trying to figure out why your car when from running great to locked, and then running again. Check/Change the plugs (probably fouled from the locked experience).

trochoid

iTrader: (6)

Carbon locking happens when rotary engines sit for extended periods of time and the solvents in the buildup evaporate and the carbon hardens. It does not generally happen on running engines unless a big chunk breaks loose, but then that causes other problems.

Engines themselves don't vapor lock, carbs and fuel pumps do.

Unfortunately from your description, the locking of the engine, then the poor running afterwards, you may have more issues than carbon. Do a compression test, I think you may have popped a seal.