ps_rx7Rage

hello everyone, I just bought this 81 rx7 put around 200 bucks into it (not to mention its very hard getting parts) anyways drove it about 120 miles before it started to want to die on me while driving 70mph, it almost felt like maybe the fuel pump is going out I had in and out power like as if it was running out of gas like can anyone just like verify if maybe this could be the symptom

Tune up
---------------------------
Fuel Filter
Auto Lite Spark plugs ( Im ordering the NGK Tomorrow)
Disb Cap
Wire Set
Oil Filter
Thermostat and Gasket
Replaced fuel lines due to leaking old lines (Next to Fuel Filter)

Symptom: Cutting in and out sometimes for 10 secs then full power again then back to no power and of course some power I was lucky to make it home

Also when I installed the fuel filter the side that saids "IN" on the filter they mean "in" from the gas tank? and other end to fuel Pump???

Thanks for any feedback

trochoid

iTrader: (6)

Welcome to the forum.

Yes, 'IN' means fuel coming in from the fuel tank. The following link will lead you to the online FSMs, carb manual and other rotary related reading. Download the carb manual, the FSM nearest to your model year and the 85 manual, which is more extensive than the earlier editions.

http://www.wankel.net/~krwright/cars/rx7/manuals.html

Next time it shows signs of intermittent power, check the level in the sight glasses on the fuel bowls. Rev the engine and see if the levels drop. If they do, you have a fuel supply problem. This could be caused by a plugged fuel filter, which you're replacing, plugged fuel screen on the pickup tube in the fuel tank, plugged screens that surround the banjo bolts where the supply and return lines bolt to the carb, a fuel pump tat's on it's last leg or a hard/brittle and cracking fuel supply line.

I notice you didn't include a new dizzy rotor in your parts list. That part is as important as a new cap when perfoming a fresh tune up.

bliffle

If you have a hard time getting parts locally from NAPA or Kragens, or whatever, then do what many of us do and order from mazdatrix.com, rockauto.com or blackknight.com.

Also, a lot of parts are available from the National and regional Classifieds here on the forum, from guys who are "parting out" old cars. And there's the ever-popular ebay.

Parts are pretty easy to get and are usually pretty cheap.

themayor500

I think bliffle meant www.blackdragonauto.com blackknight.com is defiantly a martial art website.

ps_rx7Rage

Thanks all for responding, ill check out those links, I bought a carter fuel pump and the cutting in and out stopped so it was my fuel pump however few problems still remain, the timing is way off, or something when I ran the A/C my rpm's drop down to almost nothing, also the temp gauge, its wierd, the needle rises just above "c" but when im going up hill it then rises to half way, is this normal???


BTW: Checkers Auto has most of the parts I need I just gotta wait one day because they have to order the part(s)

orion84gsl

iTrader: (5)

It sounds like the throttle opener for your A/C isn't working. Don't quote me on that, because I've never dealt with it(aside from ripping it off and throwing it away) but that would be the logical first check to me. It's there to as the title says, push the throttle open a bit to compensate for the load the A/C puts on the engine. Check that out. Check your coolant level in the rad. That sounds like the temp sensor isn't getting any coolant on uphill climbs. Don't think thats possible because it's in the pump assembly but I can't think of any other reason.

Devy55

iTrader: (2)

Check your fuel pump and make sure it produces the correct PSI.

My 80 RX7 did the same thing until it died on me. It would crank but wouldn't start. Checked the carb and it was dry, so I figured it was a fuel problem and not an ignition problem.

Anyway, being in a hurry I went through 2 generic inline electric pumps and was dissatisfied with the performance. They idled rough and backfired alot.

Then I checked their PSI and one was 5.5 to 7, and the other 7 to 9. According to the Haynes RX7 manual, my car only required 3.7 to 4.7 PSI. So got a I got a Delphi fuel pump compatible with my RX7 that put out about 4.5 PSI and things smoothed out.

ps_rx7Rage

I installed a carter fuel pump which outputs 4 psi max im just trying to get this car in top condition, it only has 136,000 mils on the motor and the other owner seemede to only drive this car in summer, the paint on it is like brand new, the car it self looks showroom, however I dont think the guy took car general care of it

trochoid

iTrader: (6)

Since the PO only drove this car in the summer, the best thing you can do is a complete fuel system cleaning. Drain and flush the tank, clean out the fuel lines, change the fuel filter, which you've done, pull the banjo bolts at the supply and return lines to the carb and clean the filter screens, run a can of Seafoam through the fuel system. If this doesn't clear up most of the problems, it may be time for a carb rebuild.

Temp gauge shouldn't be going up when going uphill, I suggest doing a full cooling system maintinance. You've done the thermostat and gasket, now it's time to do a full cooling system flush. Check the condition of the radiator, visual inspection of the outside for any plugged/rotted fins, inside for any corrosion buildup. Heater hoses, fan clutch, belt, radiator cap, (pressure test), water pump and overflow tank.

ps_rx7Rage

Ok, I need new help, and it all starts like this, I drive 70 miles to work and before I get to vegas I have to drive up a mountain and then into vegas, however when I start going down the mountain, I put the car in Neutal to save gas and to help cool the car down, anyways when I shift back into 5th gear, the car hesitates pretty bad, no matter if im holding steady at 70 mph or if I take my foot off the pedal, if I Step on it I can tell its not a timing problem because I have a strong accel without hesitation and if I hold steady again back to hesitation
When I start the car up say in the morning and I start driving it doesnt do it, only when I get up the mountain and over the top the problem will start. I would also like to know if the rx7 uses back pressure through the exhaust, because I do have a exsaust leak. Thanks

Jeezus

iTrader: (4)

Not too keen on the subject, but what comes to mind is altitude compensator and loading up.

bliffle

It may be that exhaust leak because it does use backpressure.

Kentetsu

Sorry bliffle, but I have to disagree. With a rotary engine, the less back pressure the better...

I'm wondering if, while you are descending, maybe the angle of the car allows the front fuel bowl to overfill or leak into the carb? Might be a longshot...

kutukutu1

iTrader: (5)

you shold do all the things that trochoid is saying, but also check a filter that is in the fuel line that goes to the carburator, i dont know if your car has it, but mine did, my car was having the same problem after 60mph and i cleaned that filter with water, then passed mineral spirit thorugh it, and then dunked it in gasoline, connected a small hose on it and while it was inside the gasoline blew air threw the hose to clean it up and now it runs like a dream thorugh out the whole powerband. tip: you can see the filter on my signature, it's right on the entrance of the fuel line.

Kentetsu

Get the timing issue taken care of. That will probably take care of the climbing temps on hills...



.

ps_rx7Rage

well it isnt a hill its a mountain an d its like 4 or 5 miles of constant push, and someone else told me on the forum constant push will make the temp rise however I flushed the rad and it only rises just alittle now, I do have a complete flush kit the im going to do but I noticed today I have a bad oil leak come from where the engine is put togather near the dist, so its time for a engine rebuild, Thanks again for replying, I have found alot of help here and I thank everyone

ps_rx7Rage

Thanks guys for the reply lol, Ive been working on cars forever, however never a rotory engine so this stuff is new to me, it almost feels like it COULD be flooding just like kentetsu said or just to much gas is getting in the carb, I wish u guys could drive this mountain just once to see just how far up I gotta drive I mean 5 miles of pure push and going down the mountain for like 9 miles is crazy.

Btw I heard theres a fuel filter screen, Is this thing By the carb atteched to the fuel lines or in the carb where the fuel line go's in???

orion84gsl

iTrader: (5)

When I went to Deal's Gap I was pushing very very hard through about 11 miles of mountain pass (which took about an hour. 318 turns in 11 miles will take that long ) and my temp only rose slightly above normal. Was maybe close to the halfway mark. Good luck with your rebuild. Don't forget to do some porting while you have her open.

Kentetsu

Where the metal fuel lines bolt onto the top of the carb. Remove those bolts, take off the fuel pipes, and you will see the screens.

bliffle

I go up a mountain about 3-4 miles regularly without temp problems, but it's probably a little cooler here. It's a winding road and I'm usually in 2nd gear at about 4k rpm all the way.

I've sealed those oil leaks before (for several months at a time) by cleaning the area ultra-good (ending with an MEK cleaning) and then applying JB Weld. Stops the worry of getting oil all over and having an oil fire.

ps_rx7Rage

Now that ive done a rad flush, mine never hits the halfway mark but on hot hot days like 112 out side it gets close lol, but then I can almost tell when the thermostat opens cause it will get close to half and then drops plus I dont run up the mountain at 100mph either like the other retards do. then once I get into the city it sits at 1/4 and just sits there and never moves

orion84gsl

iTrader: (5)

I don't know if your running a front mount oil cooler or a beehive, but changing to a front mount dropped the temp on my gauge by about 10*C at least. Certainly a smarter design.

ps_rx7Rage

i have a front mount oil cooler, but! When I took out the rad to flush it,theres some damage I noticed to the oil cooler rad, Im not sure what the proper word is for it but, Im not sure its hurting anything, my oil pressure is normal, like I said im not sure about it, but the oil cooler rad is kind bumped up, and im thinking about getting another one either new or pull a part.

BTW Orion84gsl my cars the same color as yours. Nice color huh