Redliner223

iTrader: (6)

Alright so here in a couple weeks once I finish all my finals, I'm going to replace my bad intake gasket.
The gasket has been bad for about 10 to 15 years now, causing antifreeze leakage and it has been throwing a ghost "add coolant" light.
I don't have the know how to replace it myself so I was looking into a shop doing it for me. I contacted Rotary Performance which is about an hour drive away from me, and they told me that it would be about $440 to replace it and it would be about a 6 hour job. They told me that my thermal reactor will have to be removed (kinda scared me out of doing it myself), but that is also what I don't understand. In the repair manual just removing the carb. doesn't involve the removal of the thermal reactor.

Also I asked what is the worst case scenario that could happen and they told me that the worst thing that could happen is rusty bolts not wanting to let go and certain measures must be taken in order to get the job done right. (he didn't say that directly)


Can someone please shed a little more light on this please.
I don't want to be walking into a bloodbath with my wallet.

Redliner223

iTrader: (6)

What I really want to know is, what is all involved in order to get at the intake gasket?
Dropping over 400$ in order to replace a 6$ gasket isn't my most ideal solution but it will get the job done quicker if I let someone else do it.
The only reason I ask this is because I fear once they start messing with components around the engine some thing might break and one thing will lead to another.
I just want to be prepared and I just don't want to be surprised when something bad happens.
Thanks guys

OneRotor

iTrader: (3)

It's quite easy to remove. The only issue you may run into if you do have to remove the thermal reactor is snapping off exhaust studs. Soak everything in AeroKroil overnight and it'll come right off.

Also, tap some 20mm freeze plugs into your coolant passages in your block. It'll keep your intake cooler.

KansasCityREPU

iTrader: (9)

I don't have to remove my exhust manifold on my 1985 RX-7, are you sure the thermal reactor really need to come off? You really don't even neet to remove the carb. All you need to do is undue 4 bolts and 2 bolts to remove the intake manifold with the carb still attached. You can also leave all the emmissions stuff on and remove the whole thing as an assembly. You will need the intake manifold gasket AND the water poassage o-rings. It's the o-rings that go bad.

$400+ is way to much. Find a local fourm member if you don't feel like doing it yourself. I'm sure you could pay someone a couple hundred to do the job. I can do the job in about an hour but I'm too far away.

Redliner223

iTrader: (6)

See I'm not sure if the thermal reactor needs to be removed. The only scenario that I know of where it needs to be removed is if one of the bolts holding down the carb. doesn't want to let go.
The parts will amount to about say 50$, which will most likely include, new radiator hoses, gaskets, and coolant. Other than that the rest is for their time.
-_- Yeah, forgot to include the two of so o-rings.
Also, its not that I don't feel like replacing it myself, it's more of my lacking experience with the Nikkie carb. I just feel a little more confident in doing something that isn't regular maintenance work when someone with some experience is around to answer questions.

Jeff20B

iTrader: (13)

I wonder if I should shout WRONGO! this time. Nah, I'll just gently add to what you said in that unless you fill the ACV port with quicksteel or some other stable putty, it is unwise to install freeze plugs because the coolant help keeps the manifold from getting hot due to an open ACV port allowing exhaust heat in. Ever felt an S4 NA manifold at idle? Those'll burn yah! They don't have coolant flowing through them. And that's only from two ACV ports which I suspect are for opening the aux ports, but I'm not an FC guy so I don't know.

Also never needed to soak exhaust nuts in anything if they're factory installed at proper torque ie never molested by hamfisted sister kissers. I mean typical garage mechanics. Sorry, I don't trust those guys to work on my own cars let alone others'. But do what you gotta do.

Jeff20B

iTrader: (13)

Now, Redliner223, I've got a question for you. Do you really have a 79 or 80 with an actual thermal reactor? Or is it an 81-85 with an exhaust manifold?

Why do I ask? Because the SA22C didn't have an active ACV port due to the way they did emissions from 76-80 (or 76-79 is you're CA spec as the CA 80 had a whole different intermediate plate) and therefore it is perfectly ok to tap in a couple freeze plugs while the intake is off, and you don't need to fill in the ACV port unless you want to stop bugs from getting in. Do you have a bug problem in the DFW?

Jeff20B

iTrader: (13)

I try to avoid thermal reactor setups as much as the next guy, but from what I can remember, the TR needs to come off before the intake manifold can come off. Does that sound right to anybody?

Opeth1stgen

iTrader: (3)

I agree with Jeff that the Thermal reactor needs to come off before the intake mani, its been a while since I've worked on my thermal reactor and intake but from what I remember the lower bolts on the intake manifold are next to impossible to take off with the thermal reactor still attached.

OneRotor

iTrader: (3)

This is what I remember from when I took all the accessories off of a '79 block.

Forgot about the ACV port fill. I did that on my recent motor install. And use some RTV as lubricant on the freeze plugs.

Redliner223

iTrader: (6)

Jeff, it has the original thermal reactor and is a true TR and no it's not a cali spec car.
We don't have a bug problem in the Dallas/Fort Worth area just a lot of ants, but we kill those suckers on site at my place.

Jeff20B

iTrader: (13)

Excellent! I did the very same on my engine just yesterday. Yep, even used RTV. Maybe I can throw it in the car today if it doesn't start raining.

Redliner223, of course I was kidding about the bug thing. You knew that. So yes there is no need to fill your ACV port if you choose to install some freeze plugs, due to the TR and that it's not a CA spec car. One thing to look for once the intake is off, is whether there i any carbon in the ACV port. If there is, you would need to fill it because it's active. The only way this is possible is if someone swapped in a CA spec rotor housing during a rebuild. I had to fill in my ACV port because my housings are like CA spec housings.

On second thought, you have an SA intake manifold, which doesn't cover the ACV port. Never mind.

Redliner223

iTrader: (6)

Kinda figured about the bug thing, just thought I would humor you.
So what you guys are saying is my thermal reactor will have to be removed, and once the thermal reactor is removed installing freeze plugs will not be necessary because it is not a cali spec car.
Am I right?

OneRotor

iTrader: (3)

Installing the freeze plugs should happen regardless of where you are (except if you're trying to drive in Siberia...)

Redliner223

iTrader: (6)

Will the freeze plugs mess with me thermal reactor once I put it back on in any way?

Jeff20B

iTrader: (13)

Freeze plugs are for your intake manifold. Not for the TR. The only way to mess with the TR by blocking anything off in the rotor housings, is by filling in the air injection holes down next to the lower exhaust studs. I've seen them filled with a devcon-like putty. I've never attempted it though. I just get an RB flange which covers them along with a good TR gasket. You should get a new exhaust gasket because chances are yours is old and probably not able to seal again. http://www.mazdatrix.com/getprice.as...m=13-889B-3743

actually, the CA spec gasket is cheaper. http://www.mazdatrix.com/getprice.as...m=13-889B-8562

See them here. http://www.mazdatrix.com/e6.htm

Notice the funny little extra hole on the CA gasket? Yeah, divindriver has to put up with that. I don't since I'm not in CA.

Redliner223

iTrader: (6)

Hmmm, very interesting sorry I have so many questions it's just I've heard of freeze plugs being used but I never knew what the actual purpose was.
What would be the best way to remove the thermal reactor?
I have pick-up truck ramps that give me a three foot clearance is used an I also have harbor freight jack stands now that give me maybe a 1 foot clearance max. If I need more clearance than that I'm out of options. I'll have to find a lift that someone will let me use.

flight_of_pain

There should be enough play in the exhaust that you can pull the TR away from the block far enough to sneak a ratchet in for the lower intake manifold bolts. It is tight clearances, but possible. I typically block off the acv (in acv equipped cars), and the intake coolant passages. While this presumably gives lower intake temps, the best side effect is no longer worrying about those damn o-rings leaking.

Freeze plug writeup -> https://www.rx7club.com/1st-generation-specific-1979-1985-18/installing-freeze-expansion-plugs-coolant-ports-intake-990704/

I would spray the exhaust bolts with pb blaster or another penetrating oil for a few days prior to disassembly just in case. I cant imagine the whole process taking more than a few hours, even for a total greenhorn.

Isaac

j9fd3s

iTrader: (3)

basically since the TR has to come off, which is just a lot of work, you have 2 choices.

1. pay someone else to do it, it is like 4 hours of work, so that is like $400...

2. or spend the 4 hours yourself

i would skip all the freeze plugs and blocking off of things, the O rings last 20 years, which is long enough

mazdaverx713b

iTrader: (91)

i agree with Mike. i've never installed freeze plugs in my rotor housings and have always just replaced the o-rings with the intake manifold gasket. they last forever and there's no harm in keeping them. they make for an easier repair and there's no chance of them oxidizing the housings as a freeze plug could potentially do over numerous years and lack of coolant changes. i just prefer stock original stuff. much more reliable and easier to maintain in some senses.

Redliner223

iTrader: (6)

Thanks for all your input guys.
Hypothetically speaking, say I were to do this on my own.... what gaskets would I need exactly?
I'm in for the intake gasket, the two o-rings, what else?
I would think that is the thermal reactor is moved and found that the gasket between the TR and Engine comes to pieces I would have to replace that. Also the gasket between the TR and rest of exhaust would have to be replaced too for safe measures.
It would be nicer to do it myself..... I would also have to "persuade" a couple local members to join the fun too if they can.

j9fd3s

iTrader: (3)

yeah you need the intake gasket, 2 o rings. you might as well change the engine to TR gasket, and the TR to the rest of the exhaust, they aren't expensive.

Redliner223

iTrader: (6)

That's it, right?

clykins

iTrader: (1)

Sealant

j9fd3s

iTrader: (3)

good point, i do put a really thin layer of silicon on both sides of the gasket, its thin like see thru, saves a LOT of scraping later