Intake Manifold/Valve Cleaning Question

Hello,

Car has about 112k miles and am thinking of cleaning the valves (better late than never). Couple question:

(1) How difficult is this; i've seen a few videos on youtube but thought I'd ask;
(2) Once I take the intake out, what should I change while i'm in there...I was thinking PCV valve, oil catch can, maybe the seals on the injectors...anything else (disclaimer: my engine has not been tuned at all, it's not a racing engine)?

Thanks in advance!!

 

Corksport has a blast kit to help make it easier. Really worth it. And yeah, with the intake manifold off, all that is a great idea!

 

It’s not that hard, but if you’ve never done it before I would strongly suggest getting help from someone who has done it before. There are some things you need to know BEFORE you even attempt it. First, you need to make 100% sure the valves are fully closed on the port you’re working on and all your intake hoses are fully sealed. If any of that walnut media gets in the combustion chamber you’re going to have a bad time. Also, it’s a super messy job. It’s a small hole and once you start spraying that stuff into it, it will fly out and go everywhere. The better job you do of prepping, the less of a mess you’ll have to deal with. I usually have a box of nitrile gloves and tape a glove on the ends of any hoses I disconnect, fully tape off all the intake ports I’m not working on, and use a drop cloth with a hole cut out to cover everything but the port I’m working on. That way it’s just a matter of vacuuming the floor instead of having to try to vacuum every nook and cranny of the engine bay.


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Thanks so much for your detailed response. Will definitely look into getting help now.

 

I've done this twice now, and it may be overkill, but for a mostly mess-free process, I took a large black trash bag, cut a slit in the very bottom (not the full length) and then swapped duct tape across each opening as I moved between valves. You can hang the bag up on the hood latch to hold it in place, and then spread the edges out on either side. You will want to prep well as stated, as once you start blasting you want as little of that walnut media going over you and your engine bay as possible.

Not sure if the picture will embed, but this is how I did it.

 

It is simple but tedious. I was not into cars before I got my Mazdaspeed6 and valve cleaning was the 3rd thing I did to the car myself (1st was a race pipe, 2nd was shifter bushings). Soaked the valves overnight and used brushes so it took 2 days to finish but the car started with zero problems. Before pushing the power steering pump to the side, zip tie the belt to the PS pulley.

 

Anyone jerry rig blaster hose / vacuum assembly looking for some hose sizes / type. About time to clean my intake valves, 7 years 120k km it's time going to do it when I'm off for a week in march and it's warmer here...

I think the CS kit is great but with shipping to Canada, import fees and exchange rate it's over $160 by the time I get it to me.

 

I didn’t use media when I cleaned mine but I think I used a piece of 5/8 or 3/4” hose in the end of a shop vac hose and taped the crap out of it. I used a bunch of different picks and small screw drivers to scrape the stuff off. Then I used a wider screwdriver blade with small pieces of scotch brite to scrub off everything I couldn’t get off with the picks/screwdrivers. I kept soaking it in laquer thinner during the process. Soak it up with shop rags. Then when I was done I used the shop vac and finally hit it sorta lightly with compressed air

Spraying a little bit of something in there before you start also helps to confirm the valves are closed. The head I’m using for my build actually had one valve that had so much build up it wasn’t closing all the way. When I seen it hanging open I thought it was bent. I took the valve out. Cleaned it , checked it and it wasn’t bent. The build up was actually hitting the guide and not letting it close. Kinda crazy because the car only had around 125k on it if I remember right.

 

Kinda an old thread, but I cleaned my valves for the first time this weekend on my 2008 speed. Wanted to send my injectors off for servicing, install a damond occ, and corksport seals. She is at 87k miles. The valve cleaning went really easy for me compared to just getting the manifold off and the fuel rail off.

I soaked the valves over night in B-12, used the corksport tool, fine walnut media, a 5hp shop vac, and a 4.6 gallon cali air tool 4620ac. Each valve took just 15-20m. Well the first one took like 45m because I was scraping at it with picks thinking my compressor would be underpowered and from watching too many youtube videos where folks picked at it till their hands were falling off lol. It really wasn't all that bad in the scheme of the whole project.

I was a little worried I spent too much for the corksport valve tool, but man I am so glad I got it. There was practically no mess and I think it really helped seal things well so that my compressor could do the trick.

One quality of life tool I'd recommend for the project is a headlamp. I got a 'foxelli' from amazon for about $9 and used it quite often, both for cleaning the valves and just seeing pesky bolts like the dipstick that has to come off.

The power steering pump on the gen1's is a pain point. I elected to leave on the serpentine belt, loosened the top two bolts and left the bottom one in place. I simply could never get to the bottom bolt it is completely hidden and tricky to get to by feel. Used a pry bar to tilt the pump just enough to get access to the manifold bolt it blocks access to.

 

Set aside at least a full day if it’s your first time. It’s not difficult to do, there are just a lot of steps. Especially if you haven’t ever removed the intake manifold. Having a buddy who has done it along with a good amount of beer will help a lot

 

If you cheap out on a media gun or don't have a good compressor, I wouldn't bother with walnut blasting. My experience is that it just made a mess and dusted the areas I needed to scrape still making the whole process take longer. It's a full day's worth of work for sure. I prefer just B-12 soaking and scraping with long picks of various angles. Make sure to change your oil after doing this. Your back will be bothered at the end of the day so get a back massage afterwards.

TIP: As you take off something, shove the bolts into various baggies and label the baggies accurately. For example, if there's 2 bolts of different sizes for one part, use two baggies and label them. Make sure you lube up the fuel rail and the blue o-rings on the injectors so you don't pinch them when reinstalling and the fuel rail will require a good amount of ugga duggas to take them off the injectors in the first place so I recommend leaving the injectors in to remove the fuel rail if you're sending out the injectors for cleaning, which you should. Send them to someone who tests them at our operating PSI (2K) and not just 200 PSI. I think Overspeed does this and if they do, I know they offer used fuel injectors you can just swap out for. There's a process, look into it. I should have done this if they do test at 2K PSI. As for the fuel injectors, there's a kit out there that I can't remember off the top of my head that will replace the shit torx bolts with traditional bolts. Go slow and methodical and be anal about it. Have someone on hand either text, messenger, or there with you because you will have tons of questions. That's what I did. Also, grab all torque specs before hand so you're not taking longer buttoning up.

Good luck! It's daunting, but I am a complete tool on mechanical stuff and if I can do it, I don't see a reason why no one else can't.

*edit in bold*

 

You've got some good information in your post. As for having someone on standby because "you're going to have questions". Careful to assume people's mechanical ability, the forums are a great place to ask these questions pre job and during, for example my friend engine swap I read so much that I was ready to go, just referenced torque spec during. Now I haven't done this yet myself but most people have said it's just tideous and take your time.

 

@Xlorn, did you end up just using fine walnut blast media? I've watched the videos on youtube as well and they all seem to start out with B-12 (which I dont think we can get in Canada...I think I'd probably just use carb cleaner?) and THEN blast with walnut media.

I'd like to know if just blasting with the walnut media would be good enough, because the chemical soak and scrubbing would seem to make a pretty sticky mess.

Couple of other questions:

1) How do you for sure determine when your intake valves are closed? Especially if doing this as a one man operation.

2) How did you clean the intake runners? Did you clean them with B12 and a brush first and then start blasting the valves? Or did you blast the the runners as well?

3) Any risk of not being able to fully recover the blast media?

Parts to be replaced:

- PCV valve
- Install OCC
- Intake manifold gasket
- Throttle body gasket
- Anything else?

Thanks in advance!

 

if your valves are fully closed you should get all the media out with the vacuum however if you dont that's why it's walnut media so it burns in the chamber. You dont "need" to replace intake manifold and Tb gasket if it's the first time and they're in good shape. this is the perfect time to replace injector seals and have the injectors cleaned if it's been a while.

If it's a one man operation you turn the crank a little, go check valves and see if it's closed if not turn a little more.

as for b-12 i got mine off ebay, but you can get injector cleaner at crappy tire that would probably work

to clean the intake manifold you can just spray it with the carb / brake cleaner and should get it clean

 

Thanks @Awafrican, that gives me a little more confidence with doing the job, haha...i think I tend to overthink these things.

This was last done when my car had 78,000 miles on it and I'm at 127,000 now. I did the injector seals and service then. I currently have the CS injector seals in, so if they're not leaking, I'll probably skip that step this time to save some money.

 

You can also hook up a leak down tester. I think you can rent one of you don’t have one. Then just listen for the air to stop leaking thru the ports