Finally, something like 6 years after initially asking about this, I am getting around to pulling down the intake and cleaning things. I have just a quick few questions about it that I have been unable to locate answers to through a search.

1) what is it going to take to pull the t-body off the dynamic chamber for the first time in 24 years? I would imagine simply unbolting and pulling won't cut it, rubber mallet, luck, robocop like strength?

2) how much coolant is going to come out of the thing, do i need to drain some first?

3) any chemicals/cleaners to stay away from?

 

1. It shouldn't be that hard to remove the tb from the dynamic chamber. A little gentle persuasion from a rubber mallet is generally sufficient.

2. Draining the coolant would be the more environmentally acceptable way to do it. You will certainly lose some. When was it last flushed? It may be a good time to drain it, flush with a garden hose, and refill with fresh coolant/distilled water mix. I would probably drain from the engine as well as the radiator.

3. Many chemical degreasers are hard on aluminum and should specify on the label. I'm fairly certain Simple Green is one to stay away from. A buddy picked up some "Zep" from Home Depot and later realized it's not for use on aluminum. I have soaked rotor housings in Purple Power/ hot water and never had a problem. I don't recall if it's aluminum safe so read the label if you go that route. Flexible pipe cleaning brushes should allow you to clean the inside of the runners somewhat. I would recommend brash brushes as they are gentle on aluminum and work well. Rinse thoroughly when through.
Brake parts cleaner is great for cleaning the really dirty/greasy/oily areas. I usually spray things down before beginning alternative cleaning methods. Douche the intake runners with it as well.

 

Finally, something like 6 years after originally responding to your post asking about this, I was curious when you were going to get around to it...

Seriously, though - I wouldn't remove the Upper Intake Manifold (UIM) from the dynamic chamber unless you have a spare set of IM gaskets laying around. There's really no reason to do so, as most of the cleaning needs to focus on the TB itself, not the manifold runners, upper or lower.

Your best bet is to remove the UIM and Dynamic Chamber as an assembly, and spend more time on the LIM, '6'-ports and actuators, and generally cleaning up the carboned goop that tends to accumulate on these parts. The rough interior of the runners was partly due to casting, but also designed to help prevent back-flow of air through the runners, so filling them with some mixture of aluminum-safe cleaner is your best bet, as mechanical scrubbing is tedious and ineffective.

You won't lose much coolant, as this is the topmost portion of the engine that you're working on, and above the level of the radiator; just be sure to plug off the hose coming from the back of the water pump, and I usually twist the rear return from the TB to the top of the rear housing through the lifting ring to seal the rear inlet.

Don't forget to re-lube your TB rods on both sides, or you're likely to get the 'idle surge' issue that SE owners have all experienced. Good luck,

 

I swear I almost referenced that original post, I even tracked it down to get your name, but decided against it at the last second

 

Use throttle body cleaner

 

Brake Kleen/Simple Green and a brass bristle brush for the outside of the TB. Carb cleaner inside the TB and Dynamic Chamber to remove carbon build up. As LongDuck pointed out, your best efforts should concentrate on the Aux/6-ports as they do tend to carbon up extensively. If badly carboned up, Berryman's carb cleaner or even ATF will soften up the carbon. Copious amounts of Brake Kleen, wire brushing and compressed air will remove the build up. Try to avoid removing the vacuum actuators as the gaskets are a pita to remake.

 

1. maybe you have to tap it? they dont stick much...

2. maybe 2-3 oz, make sure the hoses are good, and that the lines arent clogged

3. brake/carb/throttle body cleaner works great.

 

"There are 4 12mm nuts and a 12 mm bolt on the passenger side holding the upper part of the manifold to the lower."

So I pulled off the 2 on the drivers side and 4 nuts (as well as all hoses, linkage, electrical connectors, etc), but that bolt in the middle that I thought was short to mount that (what I think was) a vacuum line holder is actually long and runs all the way into the lower manifold??? And now it's dark out....I'm quite sad right now. Someone talk to me about the lower intake manifold, what am I getting myself into here by removing it? From what I'm reading a potential nightmare. Since I have no cats do I just dump the air pump since I'm down in the bowels of this thing anyways? Most likely.

 

If you're keeping the LIM, then keep the air pump. You'd need a blocking plate to cover the air pump entry into the LIM, and if you don't have that, it will be hellaciously loud without it.

I even opted to leave in the airpump 'muffler' (for lack of a better term) that covers the air pump inlet to the air box, since it gets hellaciously loud if you remove even that little plastic muffler-thing.

At this point, I would NOT remove the LIM. It's more trouble than you need to do if you're only cleaning the UIM. Just get in there and remove the 14mm bolts - it should come right off.

When I had my injector problems back in 2002-3, I got to where I could pull out the UIM in less than 5 minutes to get to those injectors. You're just missing a few bolts, is all...

 

Thanks for the info. I would like to clean it all, especially make sure the aux ports are clean and rotating properly, and since I'll already have half of it removed and be waiting to get the injectors back from cleaning/flow testing I think I'm going to attack the LIM as well, but i'll leave the airpump. Any tricks or things I need to be aware of?

 

If the LIM and aux port actuators are still attatched, move the aux port rods in and out to see how freely/fully they move. If they stick or cannot make thier full travel, then the sleeves are carboned up and will need to be removed and cleaned. This includes the openings in the irons that the sleeves rotate inside of. I worked on an SE years ago that had over 220k on it and I swear the owner never opened up the aux ports while driving. It took nearly a week of soaking to loosen the sleeves enough to remove them. Another good reason to use Seafoam in the with each oil change.

 

Several things to be aware of digging into this project;

1. Be careful with the gaskets used to seal the 6-port actuators to the LIM. These will be brittle, and crack easily. Best to replace them with custom-cut gast material that will ensure they seal correctly. Remember that the 6-ports only operate under 4-6psi, so any leakage will immediately lead to poor throttle modulation and eventually, seized up 6-ports from not moving. As the advice given above, if you own an SE, STEP ON IT! Get those ports moving from time to time and be sure they don't lock up.

2. Be careful while cleaning - much of the carbon you're scraping off is in close proximity to the intake; you don't want ANY of it getting into your engine. Use clean rags, old t-shirt scraps, duct tape, etc. to cover the intake openings, and be sure to get all the crap out that scrape off before you start it up again. That stuff is like sand in your engine, and you want to be very careful about how you scrape it and where it goes.

3. Consider bypassing your Sub-Zero cold-start assist to preclude vacuum leaks. Most of these systems aren't working anymore anyway, but if you use it and it works, then leave it alone. For the rest of us, use vacuum caps to cap off the antifreeze squirter feed in the top of the LIM and remove what's not needed. If you leave those ports uncapped, you have an uncontrolled vacuum leak which will affect performance in some way. You can also remove the pump and tank by the passenger side firewall, along with it's wiring.

4. Actuator rods (the turny-ones) should rotate freely - if there's any binding at all, clear it up. Smooth operation is critical to gentle opening of the ports under throttle. You don't want them 'snapping' open, and if the rods are tight, they may not be opening at all. Those little actuators don't develop that much torque to turn the rods, so make sure you clean them out, lube them up, and check them from time to time.

5. New gaskets all around - except for the Dynamic Chamber; leave that one alone. It takes more effort to remove the dynamic chamber gasket, and it'll be dry and difficult to scrape off. Plus, it doesn't tend to leak, IME. Manifold to block, LIM to UIM, etc. replace all of those to ensure a good seal.

6. While it's apart, check your fuel injector seals under rail pressure. Sucks to get it back together and smell gas on your first startup. Shunt the test lead by the AFM with the UIM still off, and you'll save yourself some effort and hassle.

7. To clean the UIM/LIM themselves - I used a diluted mixture of oven cleaner and water and positioned the manifolds to hold the water while it soaked in for about 10-15 minutes. You'd be surprised how quickly this works, and it will eat out all of that dried carbon in there. Check to be sure you get an oven cleaner that's safe on aluminum, though. Let the solution sit in there for awhile, and then flush out thoroughly with fresh clean water. Same with the Dynamic Chamber.

8. With it apart, turn the TB on both sides and oil those bushings where the throttle plates pivot. This is the leading cause of 'Throttle Surge on Cold Start' as experienced by SE owners, as the aluminum bearing against the steel rods causes galling of the metals, and sticky operation. Engine Oil will work fine, but something that penetrates and holds is better - maybe silicon spray lubes.

9. Have you looked at the TB mod? Search here - it's a means to remove the 'secondary throttle' plates, i.e. the chokes on an SE in front of the primaries.

Other than these, it's straight forward. Have at it,

 

You might choose to do a little more cleaning than I did but here is what I did...

http://hroman.slac.com/rx7/project-clean/

If you plan to replace the hoses the diagram will be alot of help

 

Well that bolt did the trick, once removed UIM and everything came right off no prob, she'll be sparkling clean by Monday (looking into tb mod), but that leaves the LIM question. Once I got in there I got nervous. I know it needs to be done, when I try to manually move the actuators while they do move, it's not more than halfway for one of them, plus the runners look like the ones in bizarro's pics, lots of goop. I also see oil injectors and fragile lines which I'm not sure how to remove/reconnect properly or without snapping. If this were April I wouldn't care and just attack it, fix anything the breaks, but with winter looming if something breaks I don't want to tow it back to MI to store it. I don't suppose there's a quick and dirty way to loosen up the aux sleeves is there? If not common sense may prevail and I'll do the lower next spring. Now that I've done the upper pulling it again will be easy like LongDuck states. Again, really appreciate the info, should have used it YEARS ago when I first thought about it

 

I'm going to go for it tonight. I'm already there so going to finish the job. One question, how do I remove the plastic lines from the, well FSM says 'check valve assembly' but I would call them oil injectors mounted in the LIM?

 

If they go to the oil metering pump I've always herd to leave those alone their brittle or buy replacements first?

 

you need a thin wrench (14mm?) or be gentle with pliers. it helps to hold the metering line so when the metering nozzle pops free it doesnt also snap the line.

treat the metering lines like they are delicate, because they are. be prepared to replace the vacuum lines on the metering nozzles, they get baked pretty good

 

Pretty good writeup in the archive about replacing them in the archive, made me a whole lot less nervous about pulling the lower.

 

So close, cleaned, lubed, injectors back, everything reinstalled with banjo bolt in rail. Fires right up after a quick jump, didn't see/smell any fuel leaks so I figured I'd give it a quick drive, hit the headlights, everything dies. Main fuse/fusible link (whatever it is) must have blown for some reason. Now I have to dive into electrical and figure it out....yay.....

 

Well, you're getting there step by step,