subject says it all. I just went mechanical and the problem is much more apparant.
Getting bad gas mileage too.

 

Your mixture is probably off then. try messing around with that. Oh yea, plug up your shutter valve too while your at it. That thing wreacked havoc on my GS.

 

I have the mixture set to about 1 1/4 turns out.

The shutter valve is inoperative; larger hose is plugged with a spare lug, smaller hole is left open.

I'm thinking I have dirty secondaries that are not operating. I have a carb rebuild kit but after my "experiment" with a spare carb I'm hesistant to try it again. I wonder if something could have gone wrong with the float level or the needles. Did a search and came up with nothing.

 

Was this happening before the mechanical secondaries?

Seems to me that with mechanical secondaries, if you just floor it at low rev's or an otherwise inappropriate time, of course it's going to fall on its face. I've heard mixed comments about this whole mechanical secondaries business (for a stock carb anyways). This falling-on-it's-face thing is well along the lines of what I've heard.

There are a few things that can cause the secondaries to not open properly. They've all been written about before, try your search again?

AND...

82transam, what is it that causes you to think that the idle mixture adjust screw has *anything* to do with what happens when you're at full throttle with the secondaries open?

The "idle" mixture adjust screw is just that - it affects idle mixture. It can cause hesitation when you first hit the gas, if it's set badly, but I strongly doubt this has much to do with the problem at hand.

 

no no the problem was there before, it is just easier to pinpoint now. i can wind it up to redline using only the primaries and it still dies when the secondaries open.

I'm not so sure they are not opening, just that they are fouled up and flowing too much fuel or something

 

It sounds like your accelerator pump could be shot and/or your secondary jets could be messed up some how. Could be time for a carb rebuild.

 

may be a dumb question, but ... if the problem was the before, did you check the filter and pump?

 

filters are always fresh, fuel pump is an issue that I'm not so sure about. I know how to test the fuel flow I just haven't gotten around to it yet been too busy.

I've got a spare carb I might try, but I doubt its any better than the one on now.

I was playing around with it today; I can just barely get on the secondaries and it will accelerate ok, but the more throttle I give it the rougher it runs until finally at WOT the whole car is shaking and won't go any faster.

 

Ummm, cause my GS was having similar problems and adjusting the mixture made it better. Whatever, I'm no carb expert. I don't even like carbs anyway, but looks like I'm stuck with it for now.

 

hijack
how do you do that?
end hijack

gamble

 

check your haynes manual. You unplug the line at the carb, turn on the key, and you should have a certain fuel flow per minute.

 

Well, I can understand how adjusting the mixture could have fixed a stumble when you first hit the gas, but it *could not* fix what he's talking about at WOT. The idle mixture adjust has *no* effect during those conditions as far as I understand.

 

Is your float bowl solenoid hooked up to the single positive wire?
Your secondaries are'nt wired correctly if you have any doubt that they are operating. You should be able to look down the carb and see them begin to open at about two/thirds of the primary travel. They should all 4 be straight up and down at WOT.

This "falling on its face" thing is exactly what the other AP mod is supposed to remedy. However, you should not be having such difficulty even without that mod.
Keep in mind, one persons idea of "falling flat on its face" might be anothers idea of a simple bog. I'm not doubting you have a problem, just saying that as much detail as possible helps a little more.
Are your air bleeds all clean on top? If not, it can cause you to be sucking out way to much fuel.
AP failure would certainly cause 'nothing' to happen when you romp her, but does not explain excess fuel consumption.
An unhooked floatbowl solenoid can cause severe flooding in the secondaries.
...Every bitty detail you can give 'll help.

 

All those wires on the passenger side off the carb are messed; some of them aren't connected to anything, others I'm sure are miswired. Some sort of diagram would help me out immensely in that area.

I can feel the secondaries start to open at 2/3rds throttle; like I said something is happening its just not turning into power. And I can smell fuel or something when they start to open.

Quote:

This "falling on its face" thing is exactly what the other AP mod is supposed to remedy. However, you should not be having such difficulty even without that mod.
Keep in mind, one persons idea of "falling flat on its face" might be anothers idea of a simple bog. I'm not doubting you have a problem, just saying that as much detail as possible helps a little more.

I mean falling on its face I mean exactly that. The car runs fine on flat land; any incline just sucks the power away. I'm running entirely on the primaries, and with the mechanical mod I can only get about 2/3rds pedal so its even slower than before. Any kind of hill and the most I can do is 55.

Quote:

Are your air bleeds all clean on top? If not, it can cause you to be sucking out way to much fuel.
AP failure would certainly cause 'nothing' to happen when you romp her, but does not explain excess fuel consumption.
An unhooked floatbowl solenoid can cause severe flooding in the secondaries.
...Every bitty detail you can give 'll help.

I need to consult my Haynes manual about the air bleeds. I don't know what those are. I'm going to try a spare carb this afternoon, I need a quick fix for the time being. Or I might disconnect the secondaries entirely and see how it runs. I could get more throttle that way at least.

 

Hmmm, I always thought it did. Oh well, like I said, I'm no expert, I was just under that impression.

 

-----------------------------------------------------------All those wires on the passenger side off the carb are messed; some of them aren't connected to anything, others I'm sure are miswired. Some sort of diagram would help me out immensely in that area.
------------------------------------------------------------
The float bowl solenoid is on the drivers side of the carb. It's got one wire plugged into it.

***I wrote:
"Your secondaries are'nt wired correctly if you have any doubt that they are operating. You should be able to look down the carb and see them begin to open at about two/thirds of the primary travel. They should all 4 be straight up and down at WOT."

I mean, I want you to look down your damn carb and tell me what you see!!!

------------------------------------------------------------
I can feel the secondaries start to open at 2/3rds throttle; like I said something is happening its just not turning into power. And I can smell fuel or something when they start to open. ...

...I mean falling on its face I mean exactly that. The car runs fine on flat land; any incline just sucks the power away. I'm running entirely on the primaries, and with the mechanical mod I can only get about 2/3rds pedal so its even slower than before. Any kind of hill and the most I can do is 55.
------------------------------------------------------------
What the hell do you mean? That says there's a serious binding problem with your linkage. (Of course, you would be able to tell that if you LOOK DOWN YOUR CARB!!! (I'm just playin'. ) Just rotate the throttle linkage by hand.

Don't worry about the airbleeds.
How do you know your MPG sucks? Have you actually clocked it? (It's important info.)

 

Okay, here is what I did last night

took the night off work to work on my damn car

I switched to another carb, but had pretty much the same problem and even less power.

So what I notice is that plates on the secondary don't go straight up and down; even when the linkage is rotated all the way. The are at about a 45 degree angle. Thats all the way, lock to lock. As far as they open is about 1/2 way.

When I say i can only get 2/3rds throttle, I didn't mean the gas pedal would stop. I'm saying that if I go any further than that, the point where the sec. start to open, the car won't accelerate.

I'm pimpin' my dads Passat right now; trying to get in touch with a local guy to see if he has a spare carb. Basically I think I'm over my head. If I can get my dad to rebuild the carb I'll try that; he did my sisters '7s carb and it worked. Its going to be a couple weeks before I get this bitch sorted out I guess.

 

Good LORD!
Is there a whole crap load of slack at the throttle cable when it's just resting closed? Tug on it a little, and see if there is.

I'm wondering if you have the second saftey throttle return spring messed up. I no longer have that garbage on there, and I can't remember how it works. I just yank all that off the carbs I get! (Kinda stupid on my part cause now I can't help as much as I should be able to!)
But it seems to me I recall a few threads where people were hooking this up wrong and it was screwing things up.

WHERE THE HELL IS PEEJAY?!!!!

I'll try searching.

 

as soon as i read the first post i guessed that its running rich. and if the secondaries only open half way, that means that its only getting half the air and all the fuel (a.k.a. running rich).

after you tried all those things to fix the problem, id say the best bet is to just rebuild the carb, then youll know you fixed the problem(s).

--eric

 

Sterling,
I did notice alot of slack in the throttle cable; I'm going to look at that next weekend. I'm not sure if the scondary problem is because of spring tension or something else; I need to put my stock carb back on to be srue. I will have an update after the holidays, but for now I am looking at a spare motor with carb, just for a backup. What shoudl I look for in a motor that has been sitting since last winter? The carb is a little oxidized but I did a compresssion test *mostly by ear and flashlight* and the engine sounded good....
I will post anything that might be important after the holiday

 

I think worrying about a back-up motor is a bit rash at this point. You have a carb problem, and I doubt anything more.

But to answer your question, I would never buy an engine that was'nt running in a car when I got it, and I would'nt trust someone I did'nt know (the previous owner) to remove it from the car, either.
You're into a whole 'nother can o' worms on this, and frankly, if you can't get the carb to work, you should'nt even be concidering doing an engine swap on your own (or "guided along" by this board).

But not to frustrate you, I'll answer some of your question (what I know)-
Beware of an engine that has obviously just been cleaned. On 84-85 models (12A) the oil cooler is the water circulation kind, and the tiny O rings flatten out and start leaking under normal oil pressure. The result is an accumulation of dirt and black **** under the cooler on the rear of the engine. One step further in the O ring degradation is an actual pool of oil on the rear of the engine.
This is NO reason not to buy it.
However, oil seepage on the FRONT of the engine, same side, IS a reason to reconcider. It indicates a probable engine oil seal compromise.

Like I say, I would never buy an engine that I could'nt watch run. Here's a few things that can be looked at-
Remove the radiator cap. Check that there's antifreeze in it and not just water. If it was stored with just water, damage could've come from freezing, depending on your area, but it's doubtful. You'll know soon enough when you start it. However, concider the fact for what it is- an indication of how well maintained this car might've been thruout its life.
See if there is rainbow sheen on the surface of the coolant. If so, this is an indication that oil is seeping into the water jacket in the engine. There is no fix for a crapped out seal except for a rebuild, but more importantly is the probable cause for this- an engine that was abused- alot, or over heated due to lack of oil or water. Things get warped and burnt this way. If there seems to be aolot of oil, walk away!
An engine that has had all the emissions crap removed should only be bought based on how much trust you have in the owner! Chances are, he was looking for performance, or had some performance things on the car. He might be selling because he beat the crap out of it, and knows it's on it's way out.
If that's obviously not the case, then engine wise, the only thing you really have to worry about was did the owner maintain it by topping off the oil, ect. Check to see if the low coolant sensor- on the top of the radiator- is hooked up. This would beep enough to drive anyone nuts, and even the laziest *** would top the water off just to make it stop!
See if you can trace the oil level sensor wire, as well.
When you start it, check that all gauges work. A temp gauge that did'nt work could'nt warn the owner about his overheating engine.

Pay attention to smoothness of start-up. In a car that sits for an extended period, mice just love to live in these things. Probably smells like mouse **** inside. The problem is that they chew up the under-carpet, and then bring it into the perfect lil' mouse house- the TAILPIPE! Often, it will blow chunks of this crap out the back, and run pretty poorly for a few minutes, and then start to smoke like hell. But this should'nt last. The radiator cap should still be off, and you are now looking to see that no bubbles are rising to the surface. If so, and they are'nt stopping even after full warm-up, it's "see ya later" time.

I like to bring a few tools with me, negotiate price, and then ask permission to tune the carb, and use my cap, rotor, and plugs. I ask permission to change the fuel filter - all with understanding that if I don't buy it, I take back my plugs, cap and rotor. He can have the filter ($2, big deal...not worth removing). After I tune it, I drive it - alone! The fact that I just did what he might concider a minor miracal (most just don't know how easy a simple tune-up is) it buys his confidence that I know about these cars and won't break it.
A car will act different with another 150-200 pounder in the passenger seat. As a driver, you'll be apprehensive to fully test the engines limits, as well.

The engine may blow white smoke. It almost certainly will at start-up, but that's not a real concern. But if there's white smoke that smells like coolant, and is'nt stopping, and there's no oil in the coolant, then it's in need of a simple manifold O ring and gasket set replacement- a whopping 10 bucks shipped from MazdaTrix! (Enough for you to try for a chuck off the price of the car, though!)
If it blows blue smoke, it's burning oil, and that's bad.
After warm-up, it should'nt be blowing anything at all. When driving hard with high RPM shifts, often a puff of blue will exit the pipe. This is exceptable, provided it's NOT doing it at idle or cruise.

I generally go by these guidlines in terms of engine wear-
*90K and under- the most that should be wrong is the 84-85 oil cooler leak, and white exhaust. This is just rubber O rings decomposing in the manifold, and losing there resiliance in the oil cooler block. Not much else should be wrong with the engine. If so, it may have been beat or neglected.
*90k-120/130K- Things start to get "broken in" pretty well, and you can expect some blue puffs on hard shifts, ect. The manifold gasket probably has been changed if there's no white smoke. The back drivers side of the engine is no doubt a mess.
Now we have to be concerned about gauge and warning systems sender wires having been constantly soaked in oil and heat. The sheathing gets brittle, and they fail. Senders don't work, and it's too easy to overheat the engine. Overheating it is a craps shoot. Sometimes no damage, other times you can cook it in the blink of an eye!
*Over 130K- You decide. The engine is now over two thirds it's average expected lifespan- That's provided it's been well cared for and sweet talked alot! Epect problems and replacement parts to be needed soon, if not right away. Now you need to pay super careful attention to OMP out put, ect.

There are things I always do. I hook up a timing light to each plug wire just to ensure they are firing at all. I don't bother to time it, but I do look to see if someone might've screwed with it alot. Again, just an indication that someone played with it. Take it for what it's worth.
Of course I check oil level and color. I'm also looking for water droplets in the oil. Even in a car that sits for a long time, and even though water will sink in oil, the droplets do adhere to the dipstick- and anything else metal in the engine.
That OMP has to be working in order for me to concider buying it.

Anyway, like I said, I don't think you need a new engine. But I did'nt want to **** ya off by not answering your question based on my opinion of what you should do!

errr- S'all I know!

 

Also, have a looksee at Felix Miatas web site. It's a must read for every rotary owner.
(In fact, I get kinda pissed that people don't read that ******* site, cause it answers about 50% of the questions here!)

 

What is the address? I search with yahoo, and came up with a sight with a link to it, but then it couldn't find it.

 

I will definately take everything you said into consideration, but give me some credit I've done three engine swaps (not like this would be my first one)

 

Sorry, slinc- I did'nt know! Wadja need my engine advice for?! I've never done a swap! I've only removed engines (I have my own lil' stash -lifetime supply of 12As )
Did you have someone step on the pedal all the way, and then see if you could rotate the shaft further by hand? This would mean there's too much cable slack- an easy adjustment.