Hey I'm sorry if this is a frequent question, but to my defense I did try searching first. On to my question, I just bought my first rx-7 it's an '83 gs and from what I have gathered it has been sitting since 1999 but it could have been driven since then.. anyway. Today I was going to decarbonize the engine and upon taking out the first rotor housing's sparkplugs some anti-freeze came out maybe some water too, it was definately green though. It was probably an ounce or so. Is the engine dead? Anyway I'm bummed out now. However, I'm still going through with the MMO treatment. Thanks for any input.

 

dont bother with the mmo your engine needs a rebuild...

 

Crap. I wouldn't have a clue as to how to rebuild an engine and I think rebuilding engines are super expensive. I guess I'll just sell the car to the guy at Autozone that was interested in it.. He said he'd just put a 350 chevy engine it in.

 

hold that thought...let the others chime in before you decide on selling it see what they have to say

 

you dont really have to rebuild there is a few different things that you can chk out b4 you plan to sell. pull the intake manifold and the o-rings could be bad and leaking coolant in from there or you could have a coolant seal that went bad there is a fix for that too. go to this link, click on tech on the left handside. your going to want to find "coolant seal fix http://www.rotaryresurrection.com/. there are guys on this forum the live this fix i have done it but my leak was too bad to fix it.give those a try b4 you plan to sell!

edit: by God im not trying to start a war dont sell to the guy that wants to put a 350 in it!

 

Coolant in the combustion chambers is a bad sign, even worse if the engine has sat for a long period of time. You said the engine was seized, but didn't give anymore info on that. Will it not turn over at all? If it will not rotate at all by hand, it may be carboned locked, maybe rusted tight, may even have a broken apex seal.

You will need to get the MMO in more than just the spark plug holes. Pour some down the carb and pull the exhaust manifold off and fog in there too. While the manifold is off, look inside the exhaust ports. If the bottom of the housings have water/coolant in them, and/or rusted, prognosis is bad. Go ahead and do the treatment anyway and see if you can get it to run. Anything to save it from conversion, please.

If the engine is toast, start looking for a good used one.

 

Yeah I really don't want the conversion to take place because I honestly don't see the point of converting it. I mean it loses all appeal to me.. it'd be fake. You know.

Anyway back to business. By seized I meant it will not budge at all. That is, if I'm trying to turn the correct pulley. The one that I'm trying to turn is the one at the front bottom of the engine with the 3/4" head (my terminology is lacking atm) on the wheel? I took off the fan to get to it. I tried just moving the upper most belt towards the US passenger's side. Then, I tried wiggling to see if maybe it'd go that way any. All-in-all it's not going any where and the coolant wasn't rusty nor was the MMO that ran out. I have tried the car in gear and out of gear but it's on a slight grade facing downward. It was scotched, ofcourse. I could try to move the car facing uphill or put it perpendicular to the grade if need be.

Trochoid, I read that you wasn't supposed to pour any MMO down the carb. I guess you sugguested it becuase it's a drastic situation. If others agree I'll try it. No disrespect to you I just like having more opinions.

I'll try taking off the manifold if I can. I'm a noobie to cars, but I'm not afriad of information. I'll read everything I can. Oh yeah, I was also told that the car overheated once, maybe. Sorry for being so ambigous.

Thanks, Eric.

 

MMO down the carb will not hurt it at all. A lot of the guys are getting away from the ATF treatments out of concern for the oil control o-rings. If the engine is carbon locked, not rusted, you may have better/quicker results with Seafoam.

At this point, DO NOT force the engine to turn over, you stand a good chance of breaking an apex seal.

Don't be concerned about questioning my advice. If it is done politely, I have no problem with it. It keeps me on my toes and I am far from perfect and not yet all knowing. When I achieve that status, send flowers via Celestial FTD.

 

haha, alright. It just so happens I have some Seafoam. I have both the spray and the stuff you pour in the gas tank, crankcase, and brakebooster. I'm assuming that both the spray and the can is the same. I do have a few questions. Will mixing MMO and Seafoam have any odd side-effects? Since the rotors will not turn should I just pour the seaform do the carb to keep things seprate?

3rd and Final 7, I read about the coolant seal fix and well it's not going to work for now becuase the engine isn't running. but I assume that it was meant to be done after I got the engine going.

There was something else I was going to ask or say but I can't remember it. Oh yeah could the irons(?) be warped if it was indeed overheated? Probably best not to tell me, if they could be warped. Becuase, then all hope would be lost. lol. I hope together we get this thing running!

Thanks, Eric.

 

I seriously doubt that mixing the 2 will caise soe sort of caustuc chemical reactio, more likely the Seafoam will work on the MMO also.

As for warpage, that is more of a rebuild worry, unless the engine is totally toast now. My biggest concern at present is rust. If it is rusted badly enough, it may never break free, at that point the irons and possibly the rotors will probably rendered unusable due to pitting.

 

In a severe case like this, you might want to head to Napa and get some "Powerfoam". Run a search on it and you will find the info on how to use it. The engine might be fine once you get the carbon/rust broken loose. Good luck!

 

Powerfoam is by Amsoil IIRC? Unfortunately around here all I have is Autozone, Advance Auto, and O'riley's. However I think there is a NAPA in Knoxville but I never go to Knoxville.
Kentetsu, do I put powerfoam down the carb too? Trochoid, do you agrees Powerfoam may work better? I'm not trying to start problems or anything. It's just there is only so much room in the engines for this stuff and I'd hate to put something that's not going to be aggressive enough.. however I don't want anything so agressive it eats things it shouldn't.

I just woke up, so please excuse any ridiculousness that I may have left behind.
Eric.

 

well, I found a local NAPA and they don't carry the stuff. So, I'm going to try to find some amsoil elsewhere if I can't find any maybe one of you guys could list me some on ebay or whatever. unless shipping would be super ridiculous.

 

order everything online thats all I can tell you.

Napa and Carquest dont carry stuff for foreign cars that much.

 

you could try turning the engine. there are ways of unseezing ya know

 

Turning as in starting it or turn as in using a breaker bar and a 3/4" drive? Because I have tried the breaker bar and it's not moving.

 

OK, the idea here, since the engine has been sitting, is to soften the carbon up with the hopes that the carbon is locking up the engine and not the rust. MMO, Seafoam, Powerfoam, the carb cleaner that the Ford dealerships carry, ( great stuff, it foams and doesn't evaporate away quickly), whatever, use something.

A little theory behind all of this for explaination and clarity. Carbon is present inside the engine. It is left over ash from the combustion cycle. On a running engine the carbon retains some elasticity/pliability because it has absorbed fuel. The longer an engine sits, more fuel evaporates out of the carbon, this leads to the carbon solidifying and can cause the engine to become carbon locked. Carbon gets into everything. Anyone who has torn down an engine can see the carbon that has worked it's way under seals, filled in the voids between the seals, spring and grooves. Net result is the seals have lost thier full range of motion, or in the extreme, are frozen in place an cannot move. Seals affected are the side, corner and apex seals. Carbon can also build up on the housing surface, particularly between the spark plugs and the exhaust port. The oil control seals can also be affected, but that is a later treatise.

The purpose of introducing the above mentioned products into the combustion chamber is to soften said solidified carbon. This is done to free up the seals and springs, allowing them to move. Forcing a locked engine can damage these seals, which is what we want to avoid. The only part of the engine that these products have an even remote chance of damaging are the oil control o-rings and that possibility is slim and none.

It can take as long as a week to free up a severely carbon locked engine. Introduce the agent of choice into every available combustion chamber opening, let it sit for 24 hours then try to turn the engine. The e-shaft bolt is the best place to apply torque to, to rotate the engine. Start with a cw motion, looking from the front. If no or little movement, rotate ccw. DO NOT force. If movement is gained, work the engine back and forth. If it stops in both directions, introduce more softening agent, move back and forth again to spread out the fresh agent, then let it sit and come back the next day. Continue this proceedure until the engine can be easily rotated 3 full turns.

My fear with this engine in particular is that is is rusted in place and not carbon locked, however it is at least worth a try to get it running.

Nicholas P., I have read a good number of your posts. My best advice to you is use your mouse and not the keyboard until you have a better understanding and knowledge base. I don't mean to sound harsh, but you have frequently given bad advice which I suspect is based on a lack of full understanding of how some of these things actually work. As a general rule, forcing something is usually not the best approach. One must first understand what is preventing something from working the way it should, then approach from that knowledge base.

The advice you gave in your previous post could cause damage to his engine, to the point he may need to tear it down and replace broken seals.

 

Thanks Trochoid, but I understood the concept.. I guess I am acting hardheaded and I really fear that I'm going to mess up somewhere.. I'm sorry if you have lost confidence in me. lol. I'll go get the seafoam as I could not get the amsoil. I don't know if'll be able to take of the exhaust manifold. But pretty much now I just need to get as much MMO or seafoam in the engine as possible?

 

The goal is to get the solution into each of the "chambers". That means spark plug holes, down the carb, and the exhaust ports. Anything less may not be effective.

 

Yeti, I have not lost confidence in you. You've shown concern about doing the proceedure without harming the engine and a desire to do it properly. That's good, you get 2 stars for the effort. LOL. I posted the long explaination to help everyone understand the basis of carbon lock, it wasn't just for you. There seems to be a lot of misconception about carbon lock and I was trying to clear that up.

You really need to get the exhaust manifold off because that is the only way to get the solution into the bottom part of the housing, depending on the position of the rotors. It is in this area that the engine is most likely locked. The apex seals can stick to the carbon on the face of the housing, they rarely stick to the side irons enough to lock up. Seals sticking in thier grooves/seats usually won't cause an engine to lock, just makes it harder for the engine to turn over and build compression. When they stick to the housing face, well that is a bigger problem.

I support your choice of Seafoam over the MMO in your situation. Keep us posted and I wish success.

The exhaust can be a pita to remove, if it hasn't been touched for years. Get a can of P B Blaster and soak all nuts and bolts over night, respray again before you start wrenching.

 

As always, good information from Trochoid.

One other tip for removing the exhaust manifold that can save you a lot of trouble; clean off the exposed threads with a wire brush before you try to remove the nuts. You can get one that fits into a drill that works great. And PB Blaster is definitely the stuff you want to use, much better than liquid wrench/WD-40.

If you take your time and do this right (which it sounds like you are doing) then you might be able to save this engine. And if the engine is toast, then this is stuff you would have to go through anyway to install a replacement. Hang in there man, it will be worth it!

 

Mucho Gracias lol. You are right I am wanting to be extremely carefull not to break anything.. I value stuff to much to just go out there and destory it.. heh.. Anyway.. I think autozone has PB blaster so I'll go out there and survey the engine and see if I can do without then if not I'll make the trip.. I'm really thankful that you too are sticking with this thread and helping me.
Yet another question, and it's probably silly, do I just pour it don't the carb or pd I need to pour it down and open the throttle or choke? Would taking the carb off make things easier?

 

Pour it down each of the 4 barrels of the carb. That will spread the agent out and give you better coverage. No need to remove the carb.

Trust me, you will need the PB, I always have a can of that and brake cleaner on hand, and spares in the cabinet.

 

alright I poured it down the four barrels, but it only went down the two driver's side barrels. I looked at getting the exhaust manifold off and it looks a little crazy. I don't know if I'll be able to get to it soon or not. I'll wait for my dad to get home..

I called the junkyard that I goto on occassion and they only have a 1987 rx-7. Besides the engine, what else could I transfer over? (interior wise too) Is it difficult to move the engine over provided worst case senario and all? I'm not afraid to learn I just don't want to get overwelmed and quit or the landlord catching me working on a car.

 

There is a lot of info already here on making the 13B swap. Just run a quick search and you should come up with enough reading to keep you busy for a while... There is a bit of modification necessary, but it can be done. By the sound of things, you might be better off finding another 12a because that would be simpler. But hey, let's hope it's not a bad motor at all...