Cleaning Camshaft Spray Bars

[porschejeff]

Best way to remove press fit plugs to access these spray tubes adjacent to camshafts?

Do the tubes slide out (with a drift?) once the plugs have been removed?

Thank you in advance for your input.

Jeff

[snowman]

Drill out the plugs with a drill slightly smaller than the plug. Then use an easy out or something like it to fininsh pulling out the plug. The tubes just slide out.

I understand that stock plugs are available from Porsche. BUT I have never used them. I have always machined my own replacements. Its necessary to match them to the nearest 0.001" or less, but they must be larger than the hole by about 0.003" so that they press in and will not fall out. I also advise using red locktite to help secure the plugs.

If you are not comfortable with these instructions, please use a Porsche machine shop to do this task for you. In other words if you have to ask for more help, you probably shouldn't be doing it. Its really an extreemly simple plug to make on a lathe and any machinist would not hesitate to make it, but if you have to choose a machinist why not use one that does Porsches all the time.

If you have to buy them, the lot should cost about $50 from a machinest. More of a mininum charge than what they should sell for ie about a buck each.

[Fishcop]

Snowman is right, they are real simple. Factory replacment plugs are only a few bucks, I think all four cost me less than $15 bucks... I wouldn't worry about having them made for that money.

There is another thred on the board detailing threading the hole and using a tapered plug.

[ChrisBennet]

I remove the plugs and clean them in place. There is a pin holding the tubes in place that needs to be removed before removing the tube. I would not use a drift to remove these delicate tubes.
-Chris

[snowman]

Chris is correct about the pin, its part of a plug thats on top of the tube. If I remember right it takes something like a 15mm wrench to remove the plug.

[porschejeff]

Thanks, all!

John, I saw the thread on tapping the hole for 1/8" NPT plug, thank you.

-Jeff

[rcwaldo]

Be careful when installing these tubes back into the housing. They can be installed 180degrees out, which would spray oil towards the cam covers. And they are somewhat delicate.

[ChrisBennet]

Is there anything to be gained by actually removing them from the housing once the plugs are removed? I clean them in place. am I missing something?
-Chris

[rcwaldo]

Originally posted by ChrisBennet
Is there anything to be gained by actually removing them from the housing once the plugs are removed? I clean them in place. am I missing something?
-Chris

I feel there is since one can look through them confirming they are blingin'. Holding them up to a light source helps..

[snowman]

Yes the tubes are delicate, BUT NOT THAT DELICATE. You can push them out using finger pressure with a drill bit or any round thing that fits in the hole. As long as you do not use any more than finger pressure you should not be able to damage the tubes. They are just aluminum tubes with a few holes punched in them. As long as you have the plugs and the "pin" removed, they just slide out.

Yes you should completely remove them, otherwise you may miss a spec of grunge that could foul up things.

My opinion is also that if you have not had any kind of engine failure. one that generates grunge, flakes or debre, is that you should not even take the plugs or tubes out to begin with. If everything else is absolutely clean in the engine, then don't, if you see something anywhere in the engine, grunge, debre, anything, then do it.

To clarify, do it means, to remove EVERY plug in the engine. ESpecially the ones in the crankshaft and case. The grunge hides behind the plugs, only to come out after the engine is running.

[Walt Fricke]

I've pulled these plugs this way:

Drill and tap for a small machine screw (5 or 6mm?). You don't need to go very deep (and not a big deal if you break through, but you shouldn't have to - you don't need a lot of thread engagement). Spin a nut onto a fairly long screw of proper thread, and put a widish washer under the nut. Put a socket just large enough to hold the plug over the plug. Insert the screw and screw it into the plug. Turn the nut until the washer holds the socket in place. Hold the head of the screw with one wrench, and keep turning the nut with another one until you have pulled the plug out.

A no buck extractor.

But maybe this is more work than drilling larger and using an easy out - I've never tried that.

Walt Fricke

[snowman]

Walt,

Your method sounds safer for a novice, non machinist type. The real pros "just drill it out" That statement leaves out a whole lot of nuances, so remember it ain't as simple as it can sound.

[Alan Cottrill]

if you've drilled out the plugs then you have aluminum shavings all over the housing. this is the reason I've always removed the tubes to clean them out. I like to make very sure no aluminum filings are left behind.

[ChrisBennet]

Originally posted by Alan Cottrill
if you've drilled out the plugs then you have aluminum shavings all over the housing. this is the reason I've always removed the tubes to clean them out. I like to make very sure no aluminum filings are left behind.

It's a tube. Removing the tube from the carrier would only give me access to an addition a small area of the outside of the tube on either end. It wouldn't be the first time I've been dense but I fail to see the advantage to removing the tube.
-Chris

[88-diamondblue]

This is what I used last night to remove the plug. I drilled the plug, then tapped the hole and put the bolt in. Tightened the nut above the washer and they came right out. I think this is what Walt was explaining how to do it.



The tube pulled out

[Alan Cottrill]

Originally posted by ChrisBennet
It's a tube. Removing the tube from the carrier would only give me access to an addition a small area of the outside of the tube on either end. It wouldn't be the first time I've been dense but I fail to see the advantage to removing the tube.
-Chris

I come from a long line of bad worriers. if I didn't remove the tube I'd always worry that there was a little aluminum shaving pluging one of the holes to a cam journal. by removing the tube I can see for sure that none of the holes are plugged. then I can blow out the each cam journal and put it back together knowing for sure that all the shavings are gone and not hiding in a cam journal. I know I could do all that without removing the tube, but it would give me trouble getting to sleep.

[Walt Fricke]

Unlike Big Al, I must be descended from a progenitor of Alferd E. Newman ("What, me worry?"). So I don't pull the plugs often. I use screen oil filters (two plus a fabric one I can inspect before throwing away on the full race car), so I know when a bunch of junk has gotten into the oiling system (or when I have a carrier or engine case that is new to me but not new at all) and pull a plug. Otherwise I just use a lot of brake cleaner and compressed air.

Like Big Al, when I do pull a plug, I can see no reason not to fish out the tube while I am there anyway. Then I know nothing is hiding anywhere in that whole area of tube and carrier, and I can closely inspect, and even poke a little wire through, all the holes in the tube. I once saw the result of just one of those holes getting blocked at a guy's shop: the rocker wore the cam lobe down to the base circle, leaving paper thin profiles of the lobe on each side.

Diamond Blue's pictures are great. I got the idea for doing it this way from someone explaining how they made a puller to extract rear axle bearings from a banana arm - how to grip in or through the center and pull against the outside, sort of the reverse of the usual gear pullers. I think I may have used a smaller diameter machine screw, perhaps because I am one of Snowman's non-machinists and fret a lot trying to get a drill bit started exactly in the center of something, and then about keeping it at right angles with a hand drill motor. Using a scraggly collection of worn bits doesn't help, but luckily aluminum is pretty easy to drill.

Walt Fricke

[Jim Williams]

Just another observation... I just did this a couple days ago, and only removed the plug from one end. There is really no need that I can see to remove both plugs, as the tube extracted easily enough from one end. I use a length of wire with a small loop in one end, and some cotton string wrapped around two fingers 5 or 6 times, then slipped off the fingers and into the loop in the wire and dipped into some mineral spirits, then pulled through the tube several times. Makes me feel better to have it out, easier to hold up to the light and check it out. Then high pressure air to blow out the tubeand also blow out the drilled passages in the housing itself.