no start rx7

[popsboomie]

My grandson has a 1986 RX 7 that overheated really bad, after overhauling the enging cranks but wont run. If you spray gas in the intake it runs good until the vapors are gone. I'm stumped as what to look for

[chibikougan]

What do you mean by overhaul? Did you replace all internals apex seal etc? Also are you sure you are getting fuel? You can check the EGI fuse in the fuse block under the hood. Are all injectors plugged in? Fuel lines connected properly?

[popsboomie]

Total engine overhaul by a Mazda dealer,rotors,apex seals you name it. It was listed on the invoice. The engine was installed by my grandson,I'm thinking an electrical problem but don't know where to start. The service manual schematic is a joke to read

[chibikougan]

From what you are saying I would lean more towards you are not getting fuel. You can easily check this by removing spark plugs and turning the car over to see if there is any fuel mist. Make sure the plug wires are not connected. When done with that pull the EGI fuse and crank it over to unflood the engine if indeed you do have fuel. If there is no fuel test the EGI fuse. Make sure the fuel feed line" The on with the fuel filter" is connected to the lower and or primary fuel rail and the line from the secondary goes back to the hardline for the tank.

http://i19.photobucket.com/albums/b168/chibikougan/FuelSystem.jpg

Here there is a link to the Factory Service Manual. http://rotarycarclub.com/rotary_forum/showthread.php?t=1790

Start there and let me know what you got. Also check back often and give me your input so I can effectively help you with this problem.

[chibikougan]

Also did you fix the issue on why it overheated? Was it the coolant seals? Flush radiator and put in proper thermostat? Pressure Cap?

When filling the S4 radiator you have to make sure and fill from the radiator then the water pump housing to make sure you get the thermostat to open when it reaches operating temp. You also may need to burp the system to get all air out.

http://i19.photobucket.com/albums/b168/chibikougan/Coolingsystem.jpg

[rotorlips]

My grandson has a 1986 RX 7 that overheated really bad, after overhauling the enging cranks but wont run. If you spray gas in the intake it runs good until the vapors are gone. I'm stumped as what to look for
make sure fuel lines are right . also, check ground wire from engine harness. mounts to block under intake . seen this missed many times before.also, check if screw fell out of pulsation damper (lower rail plastic cover over it) .you can also jump the yellow connector at the right shock tower to trigger the fuel pump. these are the common items . hope that helps.

[NoDOHC]

It could also be the resistor pack in the '86 and early '87 models years they used low impedance injectors, with a resistor bank feeding them. Make sure that you have power to one side of the fuel injectors when the key is on.