Hi guys, The intake on my new-to-me 85 QV is chipped/peeling/ratty (of course). I've read some threads on how to refinish, but none really gave me a sense of how difficult the intake is to remove and reinstall. I've done a lot of wrenching, but have never worked on a 308...so I have no sense of how impossible things are to reach or how quickly you can get into trouble with something seemingly simple. The car is in for a major and my guy is advising me to leave it alone or mask things off and paint it in the car. Thoughts? Thanks!
For the black intake box holding the air filter - It's about 5 minutes to take out the entire intake box; maybe 5 minutes to put it back in. There's the large diameter hose with a screw clamp or roll up clamp from the right side fender duct; a smaller friction fit hose underneath from the intake manifold; and the whole thing sits on the fuel injection distributor inlet and just lifts off. Easiest intake box ever to remove! If you're referring to the red intake plenum... yeah, that is more intricate to remove. Not especially difficult, but care must be taken to ensure that no washers or o-rings drop down the intake tubes to the valves. That might take a couple of hours to remove, after you disconnect the fuel injection system.
that`s what he means ... 4 hour job off/on ... be very, very careful as has been mentioned by Gordon advantage: you can clean everything underneath, check/replace waterhoses & fittings, check/clean thermotime switch, replace seal
Like the others said the biggest issue are the rings that are in the thick rubber gaskets. And some are bolts are hard to reach
See the "Pulling the Plenum off for painting" thread for lots of advice. I did mine last summer. I chose to leave the engine cover, intake manifolds and injection tubing in place. This makes it more challenging, but disturbs things the least. Obviously you'll need your mirror to see the plenum nuts on the left (front) bank. I needed to make one special tool: took a Harbor Freight 13mm combination wrench and ground the closed end down to 4mm thick and 20mm OD. This allows you to get to all the nuts. As you start lifting the plenum, I suggest leaving the gaskets atop the intake manifolds (as opposed to stuck under the plenum). This way, before the plenum's studs clear the manifolds, you can ensure all 8 collars are slid down into the gaskets. If you don't do it this way, slide 3x5 business cards over the manifolds before lifting off the plenum to stop any collars that drop! When reinstalling the plenum, I found it's easier to do with the gaskets and collars on the plenum's studs, with a little silicone to help ensure it all hangs there without dropping. Keep the 3x5 cards over the intakes until the studs go through the manifold holes. Remove the cards then check each stud with your mirror to ensure the collars remain set in the gaskets, then lower it the rest of the way. I must have dropped the nuts and washers into the valley a thousand times when reassembling. It's the hardest part of the job! Just make sure each and every nut and washer is accounted for. Advice: remove the right wheel and liner, and have a extendable flexible magnet handy. You can easily slide it across the motor atop the valley and pick up any dropped items. I actually found a nut from some prior servicing this way. I removed the plenum with the TB as one unit, but did the TB separately in the reinstall. Don't think this matters much. As far as the plenum and TB refinishing, I used chemical stripper (Citri-Strip) as I wanted to avoid any particulates in the manifold. It takes a little elbow grease but works well. Then lots of lacquer thinner and wax/grease remover. I used the red VHT Wrinkle Plus paint (available on Amazon) that others suggested. 4 light coats, 2 min apart, masking tape removed after an hour. About 1.5 days later, in the oven, set it for 200 F, removed after 1 hour, then sanded the tops. It looks excellent, EXCEPT as others have noted the VHT is not as red as the original (it has a slight orange tint). My "crinkle" is pretty good but not as "crinkly" as the original. One last thing... removing all the lines from the plenum and TB may end up cracking some if they are old. If your car runs poorly after this job, that may be the reason (ask me how I know).
If you are treating the car to a "full" major rather than just a belt change then the plenum needs to come off to get access for removal of the cam covers in order to adjust the valves. You can replace the coolant hoses that run under it as well.
Thanks, CMT... The car is in for a major, but unfortunately (fortunately) not a valve adjust. My car had a "full" major in 2005, but was only driven 3K miles since then and the valves are still set to spec. I may just have my mechanic remove the intake "while he's in there"...
You've seen this thread I presume? https://www.ferrarichat.com/forum/threads/quattrovalvole-intake-plenum-restoration.300241/
I have, thanks! The description is really helpful, but I was looking for a bit more detail. Maybe something that describes the number of nuts and bolts, which ones are the hardest to reach, special tools which may be needed, gaskets that should be replaced, etc. No prob. Maybe I'll do this and shoot a step-by-step video...
