Crank Wankel - RX7

[hgs_notes]

The engine in my sons 95 blazer has a rod knocking so we have been looking for a new car for him to beat around in. At the local grocery store they have a billboard you can post stuff for sale on. Someone was selling a 79 Mazda RX7 cheap. I figured it was a possibility for the kid, but not quite what we were looking for.

We looked at it saturday. It's been stored in a machine shed, or large garage for many years. Hasn't been registered since 2001. A previous owner painted it and must have used implement paint or some other super cheap paint cuz it was all flaking off. The tires were severely weather checked.

But it really wasn't that bad. It was solid, didn't find any rust yet. Pretty much straight body except a rear corner had some amateurish body work done to it. It appears to be a low mileage car at around 63k. It started up, though not without some coughing and sputtering. It was the first time it had been turned over since last fall so I expected that. It looks like a good original mostly unmolested car.

We didn't buy it then. But I've been tossing around the idea of using my growing skill set to do some car flipping. I don't want to do full restorations or high end builds, but this one really fits what I was thinking. I don't think it needs a ton of mechanical work. There won't be a ton of rust repair. I can clean it up, repaint it, fix what's broke and it will be ready to sell. I got it cheap and parts are still available. There is a decent market for the car when it's done too. You rarely see them in this part of the country.

So I went back today after telling the seller to get it out of the shed so I could test drive it. There were no major red flags so I worked out a deal. I will be bringing it home tomorrow after work. My goal is to have some fun with the car while working on it, maybe get my son involved, and hopefully make some money off it. As long as I don't take a loss I'll be happy and might do it again with something else later. Maybe keep doing it until I make enough money to build my dream car, which I haven't narrowed down quite yet but I'm leaning towards a Cobra kit car with some special drivetrain modifications.

Anyway, this is what I'm starting with...

[hgs_notes]

We got the RX home. No new problems on the trip.






The hood.


You can see how bad the paint is peeling.


I don't know what kind of paint was used but it didn't stick at all. Even under the license plate it was peeling off. Should be easy enough to sand it off. We took a closer look at it to see what problems we could find. I don't want to invest too much in it or fix every little flaw. Just make it look and drive good. Still no major rust spots found. Even under the spare in back was solid.


I found a set of tires for it. They are used, but barely. Got a good deal on them and will be getting them mounted and balanced tomorrow.

One odd thing we found taking the wheels off is that the wheel lugs aren't like the OEM. They should have had a wheel stud like this...


Someone had installed regular screw in studs with removable lug nuts though. Some of the studs had been welded in, others weren't. Some came off with the nuts. The nuts were the wrong style, with a shank instead of an acorn seat, a few had washers. The tires were 4 different brands, 3 different sizes, and maybe 1 is worth keeping as a spare. But the spare under the hatch is actually the wrong one. The wheel will not fit these hubs. Wrong size center hole and wrong bolt pattern.

I ordered a set of lug nuts that will fit the studs. They should come in tomorrow. While at the parts store a buddy there said he has an RX in a storage shed. Might be a possible parts donor if I need something. Will have to follow up on that.

As for parts suppliers for these cars, you may not believe it, but LMC has a division that sells parts for these and the Datsun Z cars.
http://www.blackdragonauto.com/

Parts are not exactly cheap, but available.

We are supposed to get snow/sleet/rain tomorrow so I don't know if I'll get the car out on the road with the new tires right away, but I'm really looking forward to it. I didn't find any loose parts in the front suspension, just bad rubber bushings, seals, etc. Will get it registered and insured tomorrow also.

[hgs_notes]

A couple cool things about these cars. Real light weight, about 2350 lbs. That little 1.1 liter engine makes about 100 HP, which is a good power to weight ratio. Rear suspension is a 4 link with a watts link, solid axle. It's compact yet fairly easy to work on. The boy wants to be involved and I think it's gonna be a fun project for us.

[TennesseeZ]

Looks great for the age, most are beat all to dang and back when they get that old. Had a girlfriend once who had one, a generation newer I think, it was a fun little car. And that's as far as I'm gonna go with that Can't wait to see what you do with it! I'm gonna venture you'll make a chunk of money on it when all's said and done.......................

[Low Elco]

Nice little scooter! I dig 'em.

Lotsa folks don't know that LMC started as Victoria British LTD., parts for MG, Triumph, etc.

Excited for the next phase!

[hgs_notes]

Originally Posted by TennesseeZ

Looks great for the age, most are beat all to dang and back when they get that old. Had a girlfriend once who had one, a generation newer I think, it was a fun little car. And that's as far as I'm gonna go with that Can't wait to see what you do with it! I'm gonna venture you'll make a chunk of money on it when all's said and done.......................

As far as you wanna go huh? Sounds like it was a LOT of fun. I hope your right about the money. No high expectations from me though.

Originally Posted by Low Elco

Nice little scooter! I dig 'em.

Lotsa folks don't know that LMC started as Victoria British LTD., parts for MG, Triumph, etc.

Excited for the next phase!

The guy I bought it from gave me an old Victoria British catalog with it. I saw the format and knew it was an LMC rag. Don't get too excited. Just want to pretty it up and move it down the road.

I got it registered and insured today. It's been sitting so long the license dept didn't even have it in the system.

[hgs_notes]

Didn't get time to mount the wheels back on the car. Something came up where the boy and I had to go to Mankato and check out a new car for him. But the tires are mounted and balanced, and I have all new lug nuts. Just need to get some of the studs out of the old lug nuts and bolt them on. If not tomorrow, then thursday for sure.

But here are a couple more pics of the micro beast anyway.


Ready to fly away...

[70c10stepside]

Remember, a redline a day keeps the carbon away. With it being auto it kind of scares me. It was probably mostly lower rpm driven which is terrible on a rotary. A rotary is designed to spin up and stay there. The lower rpm life normally leads to carbon on the apex seals, followed by apex seal failure. Dont be afraid of rpm, the more the better. Beat it up. That is what they are designed for. Driving slow only hurts it more. I am a huge rotary fan, the 12a was a pretty decent motor. It done the job. Hope you have fun with it! Also keep in mind it has to burn oil for oil to get to the apex seals!! Very important. Keep your eye on that. Very similar to a 2 stroke.

[hgs_notes]

Originally Posted by 70c10stepside

Remember, a redline a day keeps the carbon away. With it being auto it kind of scares me. It was probably mostly lower rpm driven which is terrible on a rotary. A rotary is designed to spin up and stay there. The lower rpm life normally leads to carbon on the apex seals, followed by apex seal failure. Dont be afraid of rpm, the more the better. Beat it up. That is what they are designed for. Driving slow only hurts it more. I am a huge rotary fan, the 12a was a pretty decent motor. It done the job. Hope you have fun with it! Also keep in mind it has to burn oil for oil to get to the apex seals!! Very important. Keep your eye on that. Very similar to a 2 stroke.

Thanks for the info. I've been doing my research on it too. Which echos what you are saying. Even though it was an automatic it's still geared to run pretty high rpm at hwy speed. BTW, after I got the new tires on it today I got it out for a test drive. Lets just say that I'm fairly certain I cleaned out a few carbon deposits. It pulled strong all the way through to red line. Didn't quite get to red line in 3rd, but close enough.

The tires did the trick though. It rolled along quite well. No major shakes or worries. I had a blast. Here's 1 pic. I cant post the rest without legal problems...


The rear hatch lift struts are shot, got those on order. I just noticed that it has 2 completely different door panels. I'm also trying to find some new wheel studs. A few are just bolts with the heads cut off and 1 is missing cuz it was stuck in the lug nut. And I think the original color is this bronze.


I kinda like that. But might keep it red. I don't know yet.

[rambler]

I like those RX7s... looks like you found a good buy...

[hgs_notes]

Once I got my work done I went to play outside. It was about 50F here today and we haven't had but maybe 1 other day this year at that so far. The goal today was to wash it, get the new wipers on, maybe find another wheel stud. I got 1 and a half of those done.

I took it to the car wash. It cleaned up pretty good.



The car wash owner is NOT gonna be happy when he gets a look at that stall.





Still a little of the old red on the hood and rear quarter where the body work was done.


I wanted to get some highway miles on it and was gonna take it to New Ulm on a parts run. Half a block from the house some dumb kid pulled out in front of me. I hit the breaks hard, the engine stalled, and it would not restart. Wouldn't crank, there was no power at all. I open the hood and see this...


Thats the negative battery cable. The cable end melted into 2 parts. I'm just thinking wtf now? Then I noticed the positive cable end...


It's right against the headlight opening mechanism. It grounded out and blew the other cable apart. It also had some melted bits.


I still need to get a battery hold down in there, but I took out the posts that were screwed into the side post battery. I replaced the ends with new side post style ends. That gave it a lot more room. Thankfully I don't think I fried any other electronics that weren't already out of commission.


I will try to find some covers at the junkyard for added isolation, and the battery hold down.

The wipers I got yesterday were the wrong ones. Trico still makes inserts. They are the same style as our chevy trucks, but 2" longer. So if you are in need of wipers for your truck it is Trico 44-150. This car takes 44-170 and of course they are not in stock, so maybe in a day or 2 I will have wipers. I use rain-x on all my cars and put on this one too. It really works great.

Don't get the 45-150 style because the rubber and metal are held together with clips and it will fall apart. Wrong style.

As for the wheel stud, I just can't find anyone that offers what I want, which is like the ones on the car now. I have a few of those that were just bolts with the heads cut off. It works but you can't seat it in the rotor or axle flange so it wants to either screw in too far or not at all. I picked up some bolts and think I have an idea of how to fix that. I could've just bought a set of the original style wheel studs except 1 rotor has the studs welded into it, which meant replacing the rotor so everything matched up. And frankly I prefer having studs.

So this weekend I will get the studs fixed I think. Maybe scuff off the rest of the bright red paint. Hopefully get wipers and also the lift hatch struts. I'd like to get the temp gauge working too. And I need to clean crap out of the heater so I can turn the fan on without it sounding like I have a playing card clipped to my front fork so the spokes make that cool sound.

[rambler]

whew.. good thing the wire melted and not start a fire. or fry the electronics..

[hgs_notes]

Originally Posted by rambler

whew.. good thing the wire melted and not start a fire. or fry the electronics..

I know right?

Oh, I forgot that I need to bleed the brakes. Way too much pedal drop before they grab. I plan on flushing it out as much as possible.

[hgs_notes]

The weekend goals:
1. get the wheel studs fixed, DONE
2. Maybe scuff off the rest of the bright red paint. Not done, its actually some that stuck.
3. get wipers, DONE
4. lift hatch struts, DONE
5. I'd like to get the temp gauge working too. DONE
6. need to clean crap out of the heater, DONE
7. I need to bleed the brakes, rear done.

Plus as an added bonus I removed some of the junk out of the engine bay that's not needed, didn't work or was disconnected. There is an RX7 forum at rx7club.com and mazspeed.com with a lot of helpful info on these cars. So I'm learning as I go. As with any old car (and this is only 8 years newer than my C-10) the more you do to it the more problems you find.

When we were cleaning it out, we found a stick of radiator plugging stuff. Hmmm, couldn't be bad right? I think there is a slow leak at the bottom by the lower radiator hose. This car has been a ***** to get started and going down the road. Takes forever to warm up and go without stalling. So it has been cranking over a lot and the battery drained. But the alternator gets hotter than the catalytic converter so I think it may need replacing also.

Anyway, lets talk about the triumphs rather than the defeats.

My idea for making wheel studs was simple but effective. I got a bolt, welded around a spot about 3/4" from the end to create a shoulder. Screwed it into the axle flange and snugged it tight, then just cut the head off.




So now I have a full compliment of lug nuts.

Brake bleeding is kinda weird cuz the rear brakes only have a single bleeder on the passenger side. The brake line goes back to the rear axle, then to the driver side wheel cylinder, then where the bleeder would be is another line that goes across to the other brake wheel cylinder. It firmed the pedal some, but I will do the front then decide if I need to tear into the rear brakes or not. Trying to avoid that cuz the drums are about $95 each.

Wipers and rear hatch struts are simple enough, but I need to rig the wires back for the rear window defroster.

And I found a battery terminal cover laying on my workbench...


The temp gauge didn't work, and I found a broken wire connection, so I respliced it and the gauge moves. It's slow but it does move. The gas gauge was intermittent but seems to be ok.

The heater fan is in the passenger side foot well. So I layed on my back and figured out how to wrangle it out of there, and it just had some leaves and seeds, etc in it. It was actually pretty clean. I haven't found any evidence of rodents or bees or anything in the car. Still no hidden rot either.

As for the removal of unneeded items, it's mainly emissions stuff like the air pump and air control valve, which had already been disconnected, and some things on the carb that are pretty much useless.

Air control valve...


Air pump and sub-zero tank (this is a tank with antifreeze in it and a windshield washer pump that connects to the carb to inject it when it's really cold to help starting. It doesn't work, never did and mazda removed them with a service bulletin)


Carb junk...


There is a tutorial on how to strip all the junk off the engine, but the carb portion also recommends removing all the choke stuff, and I'm gonna leave that. The next major cleanup under the hood would be removal of what they (rx7 club) call the rats nest. It's basically a spider web of vacuum lines connected to solenoids tied to the carb and sits right on top of the engine. I fantastic source for vacuum leaks. Other than buying some new vac line and plugs, it doesn't cost anything and might solve some of the drivability issues.

I had to make a blind plate to seal off the intake manifold where the air control valve was at and I had some issues with leaks on it, until I made a gasket for it.

I got the battery charged up and tonight it actually started pretty good and I could drive it within a minute of starting it. So I have to say that was a big win for me.

Next on the list is getting the alternator tested, bleed the front brakes. Keep searching for interior parts. Need to figure out a battery hold down for it. I think I might start stripping the bondo off the left rear quarter and see what I have to deal with there. And I need to replace the antenna.

As for the body and paint, I still haven't decided on color, but the expensive part may not be the paint, but the rubber parts. Door seals, window seals and felts, etc are kinda expensive for these little buggers. I could ignore it and save the money, but I don't think I should or can. They are pretty bad.

Oh, last item, I got the horn to work. I don't know how I did, but it didn't work before and now it does.

[Low Elco]

Schnikies! Big sparks scary! Glad it came out alright, that woulda been a shame.

Good work so far, it's always fun to set a beat down machine right again.

That's a helluva way to wash a car-just take the paint off! No more dirt, simple!

I'm liking this, please continue. I wonder if a later model rubber from a salvage could be adapted to this application? Kinda like the Dakota door seals into a c-10 deal? Hmmm.

[Ol Blue K20]

Glad you're enjoying the new project.....but hey, let's not burn it down. ....sure glad that was just a close call

[hgs_notes]

Originally Posted by Low Elco

Schnikies! Big sparks scary! Glad it came out alright, that woulda been a shame.

Good work so far, it's always fun to set a beat down machine right again.

That's a helluva way to wash a car-just take the paint off! No more dirt, simple!

I'm liking this, please continue. I wonder if a later model rubber from a salvage could be adapted to this application? Kinda like the Dakota door seals into a c-10 deal? Hmmm.

Other door seals may be a possibility. They are available so I could just bite the bullet and get them, do it right.

Originally Posted by Ol Blue K20

Glad you're enjoying the new project.....but hey, let's not burn it down. ....sure glad that was just a close call

It's been a learning experience and a challenge. Exactly what I need right now.

The alternator and/or voltage regulator are toast. I'm actually in the Omaha area at the moment for work. I had some free time yesterday so searched craigslist and actually found an alternator for an 83 RX for $20. It's internally regulated so I need to study the wiring diagrams about making the change. The next owner will thank me for that.

This afternoon I checked with a few local junkyards. Didn't find any parts cars but 1 of the counter guys is a RX fan and has a buddy that restores old mazdas. He's got my name and # so we will see if he has some good door panels and other interior parts. Always good to make contacts in this hobby. If any of you reading this know someone that can help, don't be bashful.

[hgs_notes]

I got the new alternator installed this past weekend. Had it tested in the car and it seems I have it wired correctly. It's kinda funny because on this board we have an easy to follow diagram that shows how to adapt the wiring when swapping to an internally regulated alternator. On the rx7 site there are 3 threads referenced to it, all of them have different methods, and links to yet more threads on other boards, some of those links are dead. And only 1 drawing that really worked simply for my application. I referenced the 79 wiring diagram for my car, compared it to an 83 wiring diagram for the car the alternator came from and determined which wires from my harness at the firewall did the functions needed for the new alternator.

Basically you remove the old alternator. Remove the voltage regulator. Install the new alternator. Make 2 jumper wires with spade ends. Those plug into the alternator and into 2 of the blades on the original harness. Original power lead from the lug is reconnected. Done. I don't understand why those guys were making it so complicated, or wiring it up so it made power but didn't work on the dash gauge.

It's running good now when cold and sometimes stalls after it's warmed up and you take off from a stop. Which is the opposite of what it did when I first got it. Not sure my block off plate for where the air control valve was on the intake manifold is staying sealed when the engine warms up. Will need to investigate that. Could be other vacuum leaks, or flooding the engine during take off. Seems to go better if I'm real easy on the throttle or do small pumps of it. If I give it hard throttle it stalls.

But now I'm having trouble with the charging system on my C-10, and/or a ground or short to find. So I will be working on that next.

[hgs_notes]

Bled the rear brakes but then one of the wheel cylinders started leaking. They sound like there may be some metal on metal in the drum so I said the hell with it and ordered now cylinders, drums and shoes and I finally found a hardware kit for the back end.

[Ol Blue K20]

It seems like you're making good progress. Keep goin'

[hgs_notes]

Originally Posted by Ol Blue K20

It seems like you're making good progress. Keep goin'

Haven't done much with it lately. Just driving it and my son likes driving it, but with the brakes leaking its parked for now. Unfortunately my work schedule is full up for a while and I really won't get time to do anything with it.

On the other hand, I drove my C-10 to my daughters softball game today and my jimmy to her game monday. I love having them available to just run around in.

[hgs_notes]

My new brake parts came in yesterday so I took the time on a nice day to fix it. I started with the pass side since thats the one that was leaking brake fluid every where and had a metal to metal sound on it. This is what I found when I got the drum off...


That is a piece of brake shoe across the top. And it was a gooey greasy mess in there. The brake shoe...


The metal part of the shoes were both the same. Don't know where the rest of the friction material went but it wasn't in the drum...


The remains of 1 of the brake cylinder rubber boots...


The other boot also did a vanishing act.

The drum actually looked alright. I don't know how, but it wasn't grooved up or anything. I replaced it anyway, but I will get the old drums measured to see if they are worth saving or reselling. The driver side was ok. Shoes were worn but not severely. So that side just got new shoes and the drum.

Pretty easy brake job to do. The only problem I had was that the passenger side is too tight yet. I have it adjusted as loose as I can get it but it's still rubbing the drum. During the test driving I was braking hard (pedal feel is good but chattery) and braking with the e-brake only to try and burn the pads down a bit and loosen it up. It's still rubbing and it's annoying to listen to but it should go away as I drive it more.

As with all things in beaterville, once you fix a thing other problems show up and now the pass side window regulator is finicky. How often does the pass side fail before the driver side? The easy fix? Leave the damn window up!

Nice to have good brakes again though. My youngest finally drove it too. She likes my newest beater.

Yesterday while I was sitting at the GM dealer getting my work car serviced I was watching roadkill from hot rod magazine. They are basically beating on beaters every month and celebrating it, and it's right up my alley. Anyway, a couple of videos are using an old 240z with a 4.3 V-6 swapped into it. And I know there are lots of swap kits available for these rx's and I pondered it once again. Last night I was looking through builds on norotors.com and on the rx7club.com forums and you can drop just about anything you want into this car. But it's not exactly cheap. The ford mustang engine/tranny swap seems to be the easiest. The LS seems to be the most popular. There are plenty of toyota swaps too.

What it comes down to for me is whether or not I want to keep it. And I don't think I want to. It's a neat little car and fun enough to drive when there isn't something broken, but not so fun that I love it. I just don't love the car and that's a really important thing for me. I love my C-10. I love the jimmy. The mazda? Meh. I'd rather have a dune buggy. Or a 240z, or a cobra kit car, or a new camaro or 69 mustang sport roof, or...

[Low Elco]

Daaaang. Nice Brakes! Love the Roadkill as well. Have you seen they're fixing to put a new show out with the same guys? That oughta be interesting.

[hgs_notes]

Originally Posted by Low Elco

Daaaang. Nice Brakes! Love the Roadkill as well. Have you seen they're fixing to put a new show out with the same guys? That oughta be interesting.

I think I need to pull off the pass side drum and recheck it. I might have the adjuster turned the wrong ways. Pretty easy to get in there and check it. I'm still playing catch up on the roadkill episodes. I think I'm on 20, but have seen 25 already. I'm on the road for work most of the next 2 weeks so I should be able to catch up.

Today I got the longer U-bolts for my C-10 rear end, just need to make blocks so I can get it leveled out. Then it can get aligned. And I have to do front brakes on the wifes car. And replace the idler pulley on my sons car, and window regulator on daughters car, and ......

A guy I know here also has an RX that he bought specifically to do a 302 ford swap but then put it away in the barn. Lost interest. He said its too nice to part out, but knows a guy north of here that had 4 or 5 parts cars. We were at a charity auction here yesterday and both of us were looking at an old bike that was being sold. A 75 Honda CB-200T. He has several old honda CB's that he has restored. I asked about his 750 but he said it wasn't for sale, lol. This was not a bad bike, but not worth much when someone my size would never get it up to highway speeds. If it went super cheap then maybe. We both passed on it. Sold for $350.

[TennesseeZ]

Last post 04-14. That's 6 months, what's up with the RX? Seems like I read spomething about it in one of your other threads, but you're kinda leaving us hanging here. Any updates?