Jehuty77

Hello RX7 Drivers,

My names Ken but I go by Jehuty77 in the world of the internets.

My buddy just picked up a new project

1986 S4 RX7

He's not very mechanically inclined so between me and a few buddies we'll be doing most of the work.

Personally I'm a huge AE86 guy, I've owned more then I'd like to admit and wasted plenty of money on my rust buckets.

The shell he picked up is pretty close to mint, atleast compared to what im used to dealing with in the world of AE86s.

As the build goes along I'll be posting lots of questions as i know nothing about rotaries.

Here's a few pics from last night.






Currently the car isnt running, we dont know whats wrong as we haven't dived into it just yet, its been sitting in a garage for the last 7 years, the clutch pedal is to the floor, brakes are super soft but those are minor issues.

The owner said the engine was in unknown condition and to assume the worst, he said it ran perfect when he parked it but that was 7 years ago. He told us they had to do an engine swap as the original engine popped, when the new engine was dropped in the harness got hacked up for some reason, looks hacked up a bit where the wires pass beheind the alt?

I noticed the wire colors don't match where he re-joined the harness, no clue why.

I also found what looks like a coolant hose or vacuum hose that goes to nowhere coming off the back of the intake or engine, cant tell just yet, its right near where the heater core rubber hose connects to a hard line..

That brings up the question, is there an easy way to tell the difference between S4 and S5 engines? IE wire colors or something to look for? The owner said he dropped in a new engine and gave us a spare ECU, however looking up the ECU part number, it appears to be an S5 ECU.

Were all located in Hamilton, If your in the area and feel like lending a hand, feel free to PM me.

sctRota

iTrader: (2)

Get pics of the engine bay and we will know. that upper intake says it all most of the time

misterstyx69

iTrader: (142)

This quote:
I also found what looks like a coolant hose or vacuum hose that goes to nowhere coming off the back of the intake or engine, cant tell just yet, its right near where the heater core rubber hose connects to a hard line..

My guess:
It's the split air pipe for the actuators,attaches to the manifold.steel pipe goes down to the catalytic converter.

EDIT: I like the Rx7 on the hook shot..natural habitat..!..(look BOB..I bagged another one of those things!)

thewird

iTrader: (8)

S5 will have a knock sensor hole above the spark plugs on the housings. The dowels on the irons are usually bigger as well. Your probably gonna have to inject a bit of ATF into the spark plug holes to loosen up the seals and build compression. A bit of spray of starting fluid down the intake would help startup on a low compression motor which would then loosen up once running.

thewird

Jehuty77

So we got her to fire up after i patched up the mangled harness, it revs up, idles for maybe 20 - 30 seconds then stalls out.


I'm guessing the 7 year old gasoline isn't helping but there's probably other issues.









Here is where the previous owner chopped the harness right in half, i temporarily spliced in a connector, the previous owner mentioned it made the engine swap easier(why i dont know) so i figured might as well just have a connector there if its good for it to come apart.





This gray wire had some sort of wire mesh inside it, not sure why, what is this wire for?



This line for the resevoir bottle appears to go nowhere :S



Some other goodies I discovered

- Adjustable Suspension in the front
- Koni blues in the back
- Hawk HP+ Brake Pads.

Issues:
- Gas Leak near tank(Rusty Line)
- Needs new Clutch Master & Clutch Slave
- Brakes need to be bled, possibly seized calipers.
- Stalling Issues
- I'm sure theres more we havent discovered.

Mazda RX-7 EFINI TYPE

Put new gas, get rid of that problem, then see whats left to deal with.

Rathmar

iTrader: (8)

The grey wire is shielded - what is it connected to in the engine bay?

reservoir line for coolant should be connected to the port on the thermostat housing near the rad cap.

misterstyx69

iTrader: (142)

The grey wire is the O2 sensor wire.
The hose can't be connected to that Rad from what I can see,so you need to see if the Thermostat neck has an Actual Pressure cap on top of it..and sits on a plastic piece(on top of the neck) that has a nipple just for that Overflow hose.
(there were 2 types made to hold the cap.One had a flat cap and no nipple..the other had a Pressure cap and had a nipple for the overflow hose)
Just additional info: the Flat capped thermo neck meant that the RAD had the Pressure cap.
Seeing you have no Cap at the Rad,then you NEED a pressure cap at the Thermostat neck..with overflow..

pd_day

iTrader: (6)

Looks like Carlo's old car ....

Jehuty77

I think that may have been the old owners name.

What do you know about the cars history?

DaoNhatHai

iTrader: (38)

Weird seeing a yellow FC.

Jehuty77

Ok we made some progress today.

Sorted the clutch Master and Slave.

We drained the tank and put in all new fresh gas

Unfortunately the owner put the positive terminal onto the new batteries negative post, caused a minor spark but im not sure if it had any negative effect.

We searched for any sign of a blown fuse but found nothing, however when we tried to fire up the car finally it strangely wouldn't run, it would fire up strong then immediately die.

I'm not sure if its normal but every warning light on the dash is on except brakes when the car is in the "on" position right before we crank it.

After trying to start the car a million times it started to idle just a bit but even then not well, we couldnt rev it barely at all.

My worry is maybe he fried the ECU or something when hooking it up backwards.

please watch the clip below, Any help/input is greatly appreciated.

During the video you'll also hear a ticking noise i found coming from the BACV and a sizzling noise coming from i have no clue and the car giving off some beeping noise inside the cabin.

Additionally i try to demonstrate the cut hoses


Is there like CEL or way to get codes from the car?

Jehuty77

I wanted to tack these onto my last post but no edit button, here are some pics we snapped during todays work.





Notice how bad the plugs look, this was running on the old gas, really stunk like gas




Cleaned them up a bit before we ran the new gas, still made not much difference, the car kept stalling, eventually it started to idle but very poorly I'm betting they need another cleaning

Jehuty77

We searched for a vacuum leak for a while spraying Quick Start with no luck

A quick look at mangled harness

If you have any opinions on how we can find the vacuum leak please let me know

We then did a compression test, the front housing showed stronger then the rear, tho both seemed ok-ish

thewird

iTrader: (8)

Rear rotor is gone, though with the 60 psi even pulses the car should be able to idle better then that. Nevertheless, it needs a rebuild.

thewird

Jehuty77

Really? I thought it would run better then that, i mean it has some compresion still

23Racer

The motor being tired cant help. Also, cleaning the plugs with a wire brush only gets a little of the soot off the surface of the plug. The carbon that you need to be concerned with is on the ceramic insulator down inside the plug. This will provide a way for the electrical charges to travel to ground without jumping the plug gap. Get yourself a plug cleaner and clean the plugs or get yourself some new plugs. You will be amazed at how much better the car starts and runs even with all the other problems. In fact, before I did anything else, I would get some new spark plugs. That is going to be the only way you can tell what else is going on. I would also change the fuel filte4r as that could be loaded with crud from sitting for so long.

I also noticed that the front wheels are 5 lug and the rear are 4 lug. That means that someone took out the whole rear subframe and replaced it with an S4 open diff. Seems like a ton of hodge podgy stuff has gone on with the car over time and it will need a total look through before I would start to drive it around.


I hope your buddy got a great deal on this car. Its a bit of a dogs breakfast and will take a toin of work before its reliable enough to drive.

Eric

Jehuty77

He payed $700 for the car, which we figured was ok-ish.

The body itself is in great shape, even underneath is near mint, everything else though, its a disaster.

The previous owner told us he changed the front end to the 5 bolt stuff but never did the rear.

Theres no doubt the engine is tired, however wouldn't it atleast idle?

Are there any rotary guys out there who would be down for like BBQ + Beers + Work on this dam car maybe on a weekend?

We recorded this video where we demonstrated just a few of the cut wires and hoses where we have no clue where they go, wish I had like a car to compare it too.

thewird

iTrader: (8)

The engine shaking is from the low compression. The previous owner probably turned up the idle screws to get it to idle.

thewird

Jehuty77

Its so odd because I swear it ran ok in that first video we filmed, even at times being able to rev decently.

23Racer

My old S4 motor was making a max of 60 psi in both rotors and I needed to tickle it into life each time we went out on track by adding a switch that would turn on the fuel pump. An initial shot with the pump on, then turn it off and crank the motor. It would catch, then turn the pump back on. It still worked well enough once running and would rev cleanly. It just had no down low torque and was a pain to get started. It was running good enough for me to win a bunch of races in the old GTD class and $750 in prize money!!! I finally killed the motor once when I reversed the oil lines and starved it for oil and locked it up.

It sounds like this is what you are dealing with. A very low compression car will run, but everything else has to be perfect. Put a new set of plugs in, only try to start it with a fully charged battery or jump cables and I would replace the fuel filter as well as I expect that you have all kinds of crud in there. It will start and run, hopefully, as it did run well enough in the first video. Even if you get it running sorta clean, don't expect it to be reliable or make good power as the motor is very tired.

Eric

Trigger Happy

This problem is weird, it was working perfectly moments before Jehuty77's video in post number 12, he was actually whipping out the camera to get a video of it running.

It's an intermittent problem, and those are the worst to diagnose, we'll take all your suggestions into account next time we all get together, thanks a bunch guys!

sctRota

iTrader: (2)

Check the Intake Sensor on the air box. If that retaining spring is missing thats the fault. Pm me if you need help, fc's are tricky but simple things cause big problems!

EDIT: DO NOT pry at the sensor to take it out because If you do not have a spare one, that current one will proabably break during removal

Jehuty77

Were gonna get back to it this sunday, if any RX7 Guru's have time your welcome to come down, shoot me a PM if your interested

DaoNhatHai

iTrader: (38)

As mentioned in the thread already, needs a rebuild or swap at the very least. I didnt notice the 4-lug rear end until it was mentioned but something like that would make me want to comb over the care very finely to see what else is a hack job.