I have been working on a RX7 from 1983 that had been sitting in a field under a tree for 10+ years... started fine when we got it home but the cluch hydrolics were fried. So we replaced the master and slave cyliner and clutch is back, replaced the 4 o rings for the bee hive and that too car of the big leak.

Now we got it to drive, but 1st gear must be revved to 3k or else it will stall if you try 2k or below? After you get it driving things seem ok, but the rpm's drop very quickly when you let off the gas, almost like you are dragging a trailer or something? I used to have 2 first gen RX7's and I never remember it being that hard to get into gear?

I have changed the tranny fluid, oil and coolant but I think the rear diff fluid needs to be changed badly, do you guys have any other ideas as to what could be the problem?

 

Have you checked for bad wheel bearings or dragging brakes? If only it were that simple, however.

 

^wheel bearings is one thing I think is best to be replaced, so I will check and see if that is contributing.

Dragging brakes, i dont hear any griding or dragging when driving only when I use the brake pedal... but I need to check if they are freely spining with the rear end in the air.

Thanks for the ideas, they help and keep em coming

 

check for vacuum leaks, does it backfire when it drops rpm? after turning it off? check your timing also.

 

^I'll look for vac leaks, but the rats nest is in tact and all hoses are connected (I think). It does not backfire when rpm's drop or turn it off, timing seems to be ok -- it just fells like im towing something.

 

is it holding idle like it should? i should have asked this first before suggesting the vacuum leaks, but it don't hurt to check for some, also make sure you check the vacuum hose that runs from the intake mani. to the carb near the exhaust port and stuff, that hose tends to get burnt up. also, i am not sure, but do a search for shutter valve, and see if that sounds like some of your symptoms. and for ***** and giggles check your secondaries linkage, and make sure it's hooked up.

 

idel is fine, not issues there.

Where do I look for the secondary linkages? and where is the shutter valve?

 

What does it do if you go into neutral at speed? Does it still slow down quickly? If yes, maybe not the motor, but the driveline downstream, if not brakes or bearings. If it doesnt slow down in neutral, then motor or tranny, I would GUESS. Good idea to lift her up and spin the wheels as a starting point.

 

^Good idea, I will try that later today and let you know what it does in neutral at speed.

Thanks for all the help

 

https://www.rx7club.com/1st-generation-specific-1979-1985-18/common-cause-power-loss-nikki-carbureted-models-632007/
there's the secondary linkage.
https://www.rx7club.com/1st-generation-specific-1979-1985-18/maybe-will-help-all-your-timing-problems-771812/
that's the shutter valve.

 

My car backfires after I turn it off. It doesn't do it when I drop RPM however. What do you suggest this might be? I know I'm running rich, do you think that's it?

 

mine backfired after turning it off when i had a vacuum leak. . . and yes i'm pretty sure running rich has something to do with it, maybe all the fuel is not being burnt up after shutting it off so it gets stuck in the exhaust and it detonates due to the heat.

 

I think the problem is in the wheel bearings, and I am going to replace all the brake rotors and pads - diff fluid and see where that leaves me.

Thanks for all the help, I will update the post when I fix all of the above