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-   -   New (used) engine in. Won't stay running. (https://www.rx7club.com/1st-generation-specific-1979-1985-18/new-used-engine-wont-stay-running-956828/)

Jeff20B 07-31-11 02:13 PM

That is an SA manifold. Only a bit better than an FB manifold. Also your PCV nipple is broken. Time to take off the plastic part, pull out the guts, shove on a 5/8" hose, get a Fram FV266, shove its hex body inside (clamp with a couple zip ties or a hose clamp), and connect a 5/16" hose from it over to the nipple on the oil fill tube. Done. And no need for a purge valve which doesn't really work that well for PCV anyway.

You spelled quicksteel wrong. Now do a search. :)

OneRotor 07-31-11 02:37 PM

It looks as if I'll have to pull the intake manifold to fill it with Quicksteel, yes?

Will I see a performance gain by running the SA manifold over the FB manifold?

Will a FB carb work on the SA manifold?

Jeff20B 07-31-11 03:22 PM

yes x 3

OneRotor 07-31-11 03:28 PM

Thanks Jeff.

OneRotor 07-31-11 04:23 PM

Final question of the day:

OE 1985 flywheel:

http://i265.photobucket.com/albums/i...7/IMG_3909.jpg

Flywheel I got with my $60 rebuilt motor:

http://i265.photobucket.com/albums/i...7/IMG_3910.jpg

Different year flywheel? Aftermarket?

Jeff20B 07-31-11 07:46 PM

That is an 81-82 flywheel.

81-82 has to stay with that rotating assembly. The 83-85 has to stay with its rotating assembly. You know you can't mix and match these, right?

Is the clutch good? If the disc is thick you can use it. Look for around 8mm uncompressed.

How are the spring fingers? Are they basically flush? Or do they kinda stick rearward a bit? That;s a quick way to tell disc thickness without having to take the pressure plate off.

One final note for your information. The 81-82 flywheels were machined to accept a 225mm disc. Did you know that? I've used this size disc with a 215mm pressure plate and it does work. Just a little 5mm lip of unused disc material is visible around the outer edge of the pressure plate.

Another piece of interesting information. If you get the right bolt set from mazdatrix; the one with the long bolts and aluminum spacers, you can use a 225mm pressure plate on an 81-82 flywheel. I've done this too. :)

You see, there is a difference in step height.

So it looks like you have plenty of clutch options for your 60 dollar engine.

KansasCityREPU 07-31-11 08:18 PM

Another good source for flywheels and clutches.

http://www.mazdatrix.com/faq/flywheel.htm

http://www.mazdatrix.com/FCLUTCH.HTM

OneRotor 07-31-11 08:47 PM


Originally Posted by Jeff20B (Post 10727590)
That is an 81-82 flywheel.

81-82 has to stay with that rotating assembly. The 83-85 has to stay with its rotating assembly. You know you can't mix and match these, right?

Is the clutch good? If the disc is thick you can use it. Look for around 8mm uncompressed.

How are the spring fingers? Are they basically flush? Or do they kinda stick rearward a bit? That;s a quick way to tell disc thickness without having to take the pressure plate off.

One final note for your information. The 81-82 flywheels were machined to accept a 225mm disc. Did you know that? I've used this size disc with a 215mm pressure plate and it does work. Just a little 5mm lip of unused disc material is visible around the outer edge of the pressure plate.

Another piece of interesting information. If you get the right bolt set from mazdatrix; the one with the long bolts and aluminum spacers, you can use a 225mm pressure plate on an 81-82 flywheel. I've done this too. :)

You see, there is a difference in step height.

So it looks like you have plenty of clutch options for your 60 dollar engine.

I do know that I can't mix them. I'm not sure what was put in the engine by the builder. What I'm not aware of is what will happen if I use a flywheel that doesn't match the rotating assembly.

The clutch that I put on it had about 10k when I pulled it off the engine. It is ~10mm thick. PP is also in great shape. Fingers stick rearward.

I'm using a 215mm clutch on the 81-82 flywheel. The PP bolt holes line up with those on the flywheel, so I'm not too worried about that. I'm not making enough power to worry about the extra 10mm of surface area.

Jeff20B 08-01-11 09:03 AM

Look through the exhausts at the compression bathtub. Do you see the F and R marks only? Or do you also see an N mark?

rxtasy3 08-01-11 10:11 AM

RB sells blocking plugs to block off that passage from the exhaust to that port under the intake. i have them in mine. but my intake also covers it too. just a matter of removing the oil pan to install them.

DivinDriver 08-01-11 10:19 AM


Originally Posted by Jeff20B (Post 10727234)
That is an SA manifold. Only a bit better than an FB manifold. Also your PCV nipple is broken.

Minor correction, sir; the middle item with a steel base and nylon top missing the hose nipple is not a PCV valve.

On an SA, that the Altitude Compensator.

Jeff20B 08-01-11 01:15 PM

I don't think that is correct, my good man. It functions like a PCV valve, so that's more than lilely what it is. Then again, I'm dumb with SAs. I mostly know 78 and older, and 81 and later. But that valve that functions like a PCV valve can be found on all 71 to 80 intake manifolds and can be replaced by an aftermarket PCV valve with a little bit of work (keeping the steel hex in the manifold or getting an aftermarket brass one meant for gauges with the correct thread pitch and dia outside with 1/8" NPT threading inside). It has nothing to do with air pressure changes ie altitude; only changes in vacuum strength so it's partially closed at idle and only can open at part throttle (oo your idle is easier to tune). :)

Where does the FSM mention it's called an altitude compensator? I'm only aware of such a device on the side of FB carbs which you can remove or leave installed without worry.

Anyone else? Hey glazedham, you're a carb and old school manifold guy. What's your take? j9fd3s? Um, shot in the here... Sterling?

Jeff20B 08-01-11 01:25 PM


Originally Posted by rxtasy3
RB sells blocking plugs to block off that passage from the exhaust to that port under the intake. i have them in mine. but my intake also covers it too. just a matter of removing the oil pan to install them.

Possible minor correction, sir. Are you talking about the 74-75 blocking plugs/bolts RB used to sell? I tried to get some last year when I needed to block a set of MAZDA housings. No luck. So I made my own. But this guy's engine is probably newer than 75 and is already together so his ACV can only be blocked by some sort of putty from the ouside at this point.

If it was apart, he might be able to tap in some steel rod at a 45° angle because all FB housings have a simple hole under the sleeves that you can only access when the engine is apart through the ACV port at the lower leg area of the housing. Not at the bottom like a 74-75.

OneRotor 10-25-11 02:59 PM

Well it looks as if my $60 engine is bad. I'll be posting as I rip apart engines and amass parts to build a fresh 12a.

I have been soaking parts of my Nikki in ChemDip for the past month (I'm only home on weekends, and only have ~1 hour/week to work on my FB), and like an idiot, I didn't make a diagram of what jets went where before pulling them last weekend. I found the jet sizes on Sterling's site, however I don't know what goes where on the actual carb. body. Does anyone have a diagram of what stock jets (85) to put where?

Thanks

-Jim

Kentetsu 10-26-11 04:57 PM

Little jets go on the Driver's side. Big jets go on the passenger's side. Same as the barrels on the carb (large/small).

OneRotor 10-26-11 05:06 PM


Originally Posted by Kentetsu (Post 10838993)
Little jets go on the Driver's side. Big jets go on the passenger's side. Same as the barrels on the carb (large/small).

What about the orfices in the fuel bowls? Thanks for the help Mark.

Kentetsu 10-27-11 11:51 AM

Wait, the orifices in the fuel bowls are where the fuel jets go (which I was describing above).

Are you asking about air bleeds? They kinda look like fuel jets too, but go on top of the carb rather than inside the fuel bowls. If that is the case, I don't have the answer. I don't even have a stock carb I could check.

Have you checked Sterling's site yet? www.sterlingmetalworks.com

OneRotor 10-27-11 01:42 PM


Originally Posted by Kentetsu (Post 10839925)
Wait, the orifices in the fuel bowls are where the fuel jets go (which I was describing above).

Are you asking about air bleeds? They kinda look like fuel jets too, but go on top of the carb rather than inside the fuel bowls. If that is the case, I don't have the answer. I don't even have a stock carb I could check.

Have you checked Sterling's site yet? www.sterlingmetalworks.com

Yes I have looked at Sterling's site. I'll pull apart my spare carb and see what is labeled what (I'm not sure if it's the same vintage, so I wasn't sure if jets/air bleeds were changed over the years). I pulled every brass fitting out of the carb and put them in carb cleaner, because they were all gummed up.

cshaw07 10-27-11 01:51 PM

http://intertron.com/ron/carb.html

how does that work for ya?

OneRotor 10-27-11 02:33 PM


Originally Posted by cshaw07 (Post 10840079)
http://intertron.com/ron/carb.html

how does that work for ya?

That helps out a lot. It also shows me that my carb was missing the weight over the tiny check ball. Time to scavenge parts from my spare carb...

I just need to know what air bleeds go where (size #140, etc.)

Thanks.

OneRotor 10-28-11 11:23 AM

1 Attachment(s)

Originally Posted by cshaw07 (Post 10840079)
http://intertron.com/ron/carb.html

how does that work for ya?

Between this and Sterling's site, I'm good to reassemble my carb. Thanks.

Kentetsu 10-28-11 11:47 AM

Good to hear you found what you needed. :)

OneRotor 10-29-11 06:36 PM


Originally Posted by Kentetsu (Post 10841244)
Good to hear you found what you needed. :)

Now I have to figure out how to fix my crossthreaded banjo bolt...

OneRotor 10-31-11 03:11 PM


Originally Posted by OneRotor (Post 10842548)
Now I have to figure out how to fix my crossthreaded banjo bolt...

I found that the proper diameter/thread is M10x1.0. Can anyone confirm this? I'm going to get my hands on one (if it's correct) and re-thread my fuel feed this weekend.

OneRotor 12-08-11 02:30 PM

So I fixed the banjo bolt hole on my Nikki. M10x1.0 tap and a steady hand. Cleaned out shavings.

Then I looked at my work bench where I rebuilt my carb, and noticed that I have a brass weight from inside my carb still sitting on the workbench. ruh roh. I'll get a shot of it this weekend, but after looking through the exploded diagram of the carb. and taking it back apart, I can't figure out where this particular weight goes. It's if I remember correctly the longest weight of them all.

Also, with my earlier intake manifold I'm noticing that I can't actuate my primary butterflies fully. I couldn't actuate them at all with the older carb spacer on it, so I switched for my '85 carb spacer and that freed stuff up a little bit, but the primaries will only open about 40%. There is a small area on the intake manifold that is interfering with the throttle linkage. Is this normal? I'm planning on hitting it with my grinder to open up the area a little bit. Bad plan?


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