New car...1984 RX7 GSL-SE

Still trying to diagnosis my off-idle and low load issues.

The plugs:
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Can you say pig rich?

First video
This is with power to the fuel pump
Dellorto Gremlins Part I - YouTube


Second video
This is after disconnecting power to the fuel pump and running it until it runs out of fuel
Dellorto Gremlins part II - YouTube
You can hear it initially running on just 1 rotor, then the second rotor coming on a few seconds later.


Third video
This is after reconnecting power to the fuel pump and giving it some revs as well
Dellorto Gremlins Part III - YouTube

Whatever the real problem is, I think the previous owner of the carb drastically adjusted things to try to workaround the problem instead of fixing it. That would explain the crazy out of wack accelerator pump setting and the way, way too lean idle jet. Both of these things would likely conceal the problem somewhat, at least under no load. I am improving it though, so at least I have that to say!

I'm really at a loss for what this could be. Everything is correct for this engine. I don't understand it. I'm going to pull the chokes tomorrow and see if maybe they are incorrect, but I doubt it. The only thing that was wrong was the idle jets, but I've corrected that.
 
So my replace engine now light came on. So I'm on the hunt for a replacement engine. I'm thinking an S5 six port would be nice. I'm going to leave it stock and put all of my components on the new block. I'm also going to paint it like this.

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While I'm in there, I'm thinking about switching out my intake manifold and header for better pieces. I think I can crank out 180 or even 190whp (215bhp+) from this engine on stock ports.
 
It has a replace engine-light? I'm so sorry for your loss, but :rofl: how does an engineering department go from "I think we should fix this inherent problem" to "nah, just put in a signal light to notify the user when they need to get a new one."
 
frankiess said:
It has a replace engine-light? I'm so sorry for your loss, but :rofl: how does an engineering department go from "I think we should fix this inherent problem" to "nah, just put in a signal light to notify the user when they need to get a new one."
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sisko-facepalm.jpg

weeping_angel+facepalm.jpg
 
frankiess said:
What, have you ever seen a replace engine light?
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I think what Eunos meant is that there are certain conditions under which the usual "check engine" light in fact becomes a "replace engine" light - you just know that when it comes on, the damage is fatal.

Or was that the joke?
 
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frankiess said:
It has a replace engine-light? I'm so sorry for your loss, but :rofl: how does an engineering department go from "I think we should fix this inherent problem" to "nah, just put in a signal light to notify the user when they need to get a new one."
Click to expand...

On the earlier (first two gens) RX-7s, there's a light to indicate that you should add coolant. Unfortunately, if it comes on it usually means your engine has lunched itself (not uncommon) and needs to be replaced. The old joke is that that light is really the 'replace engine now' light.

On some of them, the light coming on trips a really annoying buzzer. Which adds to the whole 'replace engine now' idea.
 
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Dr_Grip said:
I think what Eunos meant is that there are certain conditions under which the usual "check engine" light in fact becomes a "replace engine" light - you just know that when it comes on, the damage is fatal.

Or was that the joke?
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Yeah, I was trying to make light of the situation.

As in, the wankels are so prone to destroying themselves, Mazda thought to add a replace engine light, that would come on occasionally, like the fuel light or the washer fluid light.

Meh, just thought there was a blink of humour in there. But thanks for proving me wrong, you life of the party you. <_<

Spectre said:
On the earlier (first two gens) RX-7s, there's a light to indicate that you should add coolant. Unfortunately, if it comes on it usually means your engine has lunched itself (not uncommon) and needs to be replaced. The old joke is that that light is really the 'replace engine now' light.

On some of them, the light coming on trips a really annoying buzzer. Which adds to the whole 'replace engine now' idea.
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Ah thanks. This is what I was looking for.

Kinda morbid. Boggles my mind how underequipped the RX-cars are to monitor their engine. Even the RX-8 just has a on/off coolant sensor. When it ticks over the standard position (which isn't even center, it's 2-3 clicks before center), it's pretty much byebye engine at that point.


Seriously, how much more expensive would it have been to add analog meters measuring temps at the front and back of the engine? :think:
 
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frankiess said:
Yeah, I was trying to make light of the situation.
Seriously, how much more expensive would it have been to add analog meters measuring temps at the front and back of the engine? :think:
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Apparently considerably. Dallas has a surprisingly large (relatively) rotary community supported by one of the biggest rotary tuners in the world, so there's quite a lot of knowledge about them here. When I asked a similar question, I was told that the issue was the extremely high underhood temps that a rotary creates was a problem for normally available automotive thermocouples at the time. Mazda was apparently unwilling to invest in a unique sensor set for the car.

At one point during the 90s, the RX-7 Turbo held the record for the highest underhood temperatures of any production car in North America, having taken away the title from the XJS. Which really is saying something.
 
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frankiess said:
Yeah, I was trying to make light of the situation.
[...]
Meh, just thought there was a blink of humour in there. But thanks for proving me wrong, you life of the party you. <_<
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Sorry, it seem that my German-ness got the better of me... :)
 
I need to add some clarification here.

The engine lasted 29 years, so 'prone to self destruction' is not really a fair diagnosis. It also blew, presumably, because my a/f mixture was far too lean and I was really abusing the engine. Right up until it died I had been winding the tachometer needle clear off the scale, because it was finally making power up there with the carb setup.

I'd also like to note that while turbo wankels do have very high underhood temps (especially third gens with the very crowded engine bay) my car actually has one of the coolest engine bays of any car I've ever owned. The block itself doesn't really get that hot because only one part of the engine is 'hot' and my header is wrapped in a very effective header wrap. While this is mostly due to carburetor physics, I've actually returned from drives and the intake manifold was actually condensing water vapor onto it's surface because it was so cold.

My car also has a pretty accurate, analogue, coolant temperature gauge. The engine was at normal operating temperature when it lost a seal. The only light on the dash was the low-washer fluid light. Again, poor air/fuel mixture caused detonation, under a pretty hard load (2nd gear pull to redline) which blew the seal. Spectre is right about the god-awful buzzer that accompanies the oil-level, and coolant-temp/level warning lights. I've only ever had the coolant level light come on, because my water pump had been leaking a little. The car never overheated, even once when I broke my waterpump/coolant fan belt, and had to limp the car home 3 miles with no coolant flow.

I've owned this car 6 years now, and prior to this, the engine had never made so much as a click out of place. In my eyes, a naturally aspirated 2 rotor is a wonderful engine when tuned correctly, and probably more reliable, though possibly not as durable compared to an equivalent 4 cylinder engine.
 
Cool. Thanks for clarifying that. Personally I have no outstanding reliability concerns about wankels themselves. It's Mazda that worries me. :p

In any case, shame about your engine. But I guess you're ready to deal with it. :D
 
Painted my velocity stacks white. I have always loved the way air horns look white, very prototypical/race

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They were kind of a neither here nor there polished aluminum. They look so much better now. I can't wait to see how they look once I get my new engine and have it painted.
 
Erm... you do know what's going to happen to the paint on the inside of the stacks, right?
 
Nothing.
At least on this engine. :p
 
hmmmm.....


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:)
 
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