Freeing up stuck/carboned 6 port actuator arm
 

Hey guys -

Helping a buddy rebuild the engine on a '90 convertible. 168,000 miles and ORIGINAL MOTOR, he has owned the car since '92!

The 6 port arms have one TOTALLY stuck and the other is sticking. Engine is apart at this point and I have the lower intake manifold on my work bench.

Is there a good way to free up the actuator arms to get them moving again? I was thinking of trying Easy-Off to try and remove the carbon build up but I think there may be more to it to get it freely moving again.

Also, the VDI is stuck but I haven't looked too far into that yet and what's needed there.

Anyone have any good tricks?

Thanks!
Dale

can you post pictures?

Thanks

I am the original owner of a '90 GXL with over 356k miles on the chassis. I bought the car new in April 1990. The original engine blew a rear rotor seal at 211k miles in Jan '02. In July '02, I bought a remanufactured engine from Ray Crowe (Malloy Mazda) and began the installation process. I would suggest that your friend remove the factory thermal pellet and replace with the aluminum plug (https://www.atkinsrotary.com/store/8...let-ARE50.html), if he hasn't already done so. It was, I believe, a stuck factory thermal pellet that led to the demise of my original Mazda engine.

My 6-port actuators were stuck too. Cleaning parts was the biggest and messiest part of my engine swap. IIRC, I used lots of Gunk carburetor cleaner and let carboned-up parts soak in it overnight, and MEK (Methyl Ethyl Ketone) which you can buy at Home Depot or Lowes. These solvents combined with brushing action was effective at removing the carbon buildup. Either of these solvents may be hazardous to your health so take appropriate precautions, if you decide to use them. I have never used Easy-Off for cleaning car parts, but it sounds like an interesting idea. I'm sure Easy-Off is a safer alternative compared to the organic solvents that I used.

Thanks! Yeah, already planning on the aluminum pellet plug, I typically do that on any motor I rebuild. It's going to be done right!

I'll get some pictures up of the carbon. I'm hoping it's not too far gone/stuck!

Dale

I'd say PB blaster, torch, and patience

Hit it with Easy-Off yesterday, it did do a good job of getting the carbon in the runners out of there. The one is still VERY stuck. Hit it with PB Blaster and still nothing.

Going to try the torch on it tonight.

Has anyone been able to remove the actuator arm? Is that even possible?

Dale

Been soaking in PB Blaster and tried some heat last night. Still nothing, it's VERY stuck.

I'm wondering if it's possible to drive the arm out and clean everything. Looks like Mazda had a seal in there at one point but it's discontinued?

Any other ideas would be great. I'd hate to have to track down a whole LIM!

Dale

If you need a part, I'd contact either Atkins or Mazdatrix.

Honestly, I think if you soak in PB blaster every day for a few days, it should come free, it has for me in the past?

You may end up breaking them in the effort, but some aren't meant to be saved.

So worked on it some more tonight.

First off, I've been soaking with PB Blaster, trying heat, you name it. Big nothing on the movement.

A while back I used a hammer and a screwdriver to try and get it to turn. It turned a little bit (like 1/4" off the stop) but hasn't moved really at all.

Tonight I worked on driving the arm out of the intake manifold. It looks like there's a brass insert into the intake manifold, then the actuator rod is pressed into it. There's a seal, C-clip, and washer at the back end of the actuator. It looks like that's how it would have to be fixed, the whole thing would need to be pressed out and a new one pressed in or the old one cleaned up.

Problems are many, though. The seal at the back end is no longer available. The arm itself isn't available new. Also, being so stuck, trying to get it out and in would be really tricky to not peen or mangle the arm so it either wouldn't come out or wouldn't go back in.

I also discovered that I did NOT turn the actuator a little bit the other day - I twisted the end of it and the end of the actuator is just about to snap off. The end of the rod is quite thin and can twist easily.

https://cimg8.ibsrv.net/gimg/www.rx7...07c9e4fcfd.png
https://cimg0.ibsrv.net/gimg/www.rx7...f310438a88.png
Dale

I've had this problem, unsolved, your diagram is very useful. The circlip is for the groove at the left side of the pic you posted, hence the retainer plate. I've removed the retainer plate and still can't get the rod to pull out. It has to be carbon build-up on the shaft. I see no other mechanism in your posted diagram and pic that would prevent the shafts removal. Also, thanks for the info. I think I'm going to try to find a way to mechanically remove the carbon from the shaft. Something like a Dremel and wire wheel, flapper , scraper, something to get the carbon off the rod. I had also jammed mine by trying to pry the rod out after removing the retainer screws. Well, it was already jammed. It moved maybe like 3/8" before becoming completely stuck.

Now that I have a replacement coming I will be doing some destructive testing on the bad one that I have to learn more about it and hopefully help others in the future.

I used a punch and a hammer to drive the rod most of the way out the other day. Where the spring part of the actuator rod on the inside of the manifold connects to the main shaft of the rod there is a little lip, I was able to get the punch on that and drive the rod down about 2" or so. This exposed the seal, C-clip, and washer on the outside end of the shaft. I put some PB Blaster in the little "well" where the outside of the rod goes into the brass sleeve and NONE of it went through.

I have a feeling the best way to fix it WAS to cut the rod off, drive it out, and replace with a new rod and seal. Since those parts are NLA you're out of luck. Also it's hard to get the rod to rotate to test it since there isn't any good way to grip the rod and rotate it - the slot in the spring end is too sloppy and deforms with force and the end that the actuator arm attaches to is too fragile, I twisted mine and killed the rod doing that.

Dale

So I got the broken rod out this weekend and the brass bushing. So far it looks like the bushing was the problem, it deformed or something and was locked on to the actuator shaft. With some sanding inside the brass bushing I was able to get it so the shaft could turn and go smoothly into the bushing.

Good thing is the bushings are available, Atkins Rotary is making them.

I'm going to do some more experiments on it and post up a guide on this. Having working 6 ports on a non-turbo car is a good thing.

Dale