overheating on warmup and a major gas guzzler
 

My fellow rx7 brethrens, I finally purchased my dream car...1985 GSL, not SE :(...about two months ago! I have some big plans for FB, but don't have the specifics or I would have posted them for my first post... I'm having some trouble with my RX7 and couldn't find anything that related to my problem so if someone could please help me out a little:


I have a 12A carb engine with 155,000 miles, 5-speed, with a manual choke. Everytime before driving off I religiously warmup my car for at least 10 minutes until the choke goes in. Recently I've been having the following problems:


1) after warmup I'll notice that the temp gauge is well over the helf line.
2) a quarter of my gas is gone for driving about 35 km's and it only got worse after I noticed my almost-overheating problem.


I've topped my coolant off with a 50-50 mixture (I live in canada, but was told this mixture was good enough), my engine oil is never left below 3/4...speaking of which I got an oil change only a month ago, I have a brand new 13psi radiator (has white residue on the cap?) and only occasionally drive my car hard

I plan to take my car in for a tuneup by our local Rx7Specialist store, but if anyone knows anything about what is wrong or what I can do to fix this, please let me know!!

Thanks!

thats alot of gas. i would seriously throw some cardboard under it and check for leaks. i don't know of any other reason it would eat that much gas. good luck.

see if the overheating stops and put the old cap back on. does the engine run smooth, how hot did it used to get ?? Some times the caps will leak, it happens with age, maybe now the systems 'sealed' The float level
inside the carb could be checked about the milage deal.

I had a new rad cap that leaked. Maybe a carb float is stuck: try tapping the float bowls with the wooden handle of an Irwin screwdriver (works for me!).

B

You mentioned about the warming the car until the choke went in. Is this the correct way to warm these cars? The choke will automatically just slide in after 10 mins? Is it okay to leave the choke open when I drive?

it's been 2 weeks
 

Does anyone know if I should be pulling my choke out every single time I start it up?

Or is it safe to simply start the car without touching the choke and to drive off...(right now temperatures are at about 5 degrees celcius outside)...

I think that the reason my gas mileage is so bad is because at every single startup, I let it idle until the choke goes in...I do this process at least 3 times a day...

every startup I let the choke decide when the car is ready to go.

I've also noticed that the only time my car starts to overheat is when I let it idle for about 15-20 mins!! I don't mean to let it sit so long, but sometimes I just plain ol' get busy. And it gets to about 3/4 of the to overheating. I think I screwed up my heat because of it...it smells like somethings burning if my heat is turned up too high.

Well, if anyone knows anything about having to startup/warmup with the choke every single time?

Thanks in advance.

check and make sure the heater core hose is flowing properly

i think it has alot to do with the rad cap

I've sent you a PM wankeled.. goto your control panel and read it, and reply/tell me what you think :)
hope that helps...

me thinks your t-statty is sticky sticky , fool me once stant never again OEM only. trev

I think the overheating could be a sticky t-stat as well..

If you let your car run for 10 minutes at fast idle (choke pulled out) three times a day, its deffinatly going to use some gas.. A good rule of thumb to use is to drive once its at normal operating temprature. The time for it to reach this temp is going to vary with ambient temprature. My car without a choke and fast idle takes about 5 minutes to warm up on a 30 degree day. Even with the lower temps that you have, its not going to take 10 mins for your car to warm up (IF the fan clutch is working properly..) Finding that "sweet spot" is going to save gas.

Look to see what your fast idle RPMs are next time you start your car when it requires use of the choke (you do not need to use it when the engine is warm). The Haynes manual I have states 2000 RPM. The ajustment requires bending a link between the throttle linkage and choke. The manual also states that this ajustment can only be made with the carb off. Maybey one of the resident carb specialist can clarify this..

Of course you need to find your cooling problem before anything.. Heat kills a rotary.

Ben

pardon the ignorance, but could someone please explain this to me. i'm trying to see if the heater core is related to my temperature/coolant loss problems.

Make sure your choke cable is tight and slick. If its loose it can jam and while driving put way too much gas in the engine, making it waste gas and run uber rich. I had this problem myself.

I ride motorcycles quite a bit, and on a motorcycle, you only use the choke to get it started, once you are moving the engine will warm up on it's own. Using the choke any more than that and you are just fouling plugs and wasting gas.

I don't know for sure but I don't see any reason it should be different for a rx7.

I don't use the choke on mine any longer than it takes for it to idle on it's own, then I shut it off completely.

If this is wrong, someone let me know.