cam spray bar plug replacment

[WERK I]

Originally Posted by 911 tweaks

I just thought of another dumb question...when I remove the spray bar, in case it has become miss directed a/o wrongly installed, can you tell me where the spray bar holes need to be pointing, as in what/where should the oil be pissing on? the area where the rocker rides on the cam lobes?.
Bob

The orifices should be pointing down towards the head. There are only two ways the spray bars can line up, orifices pointing up(incorrect) or pointing down(correct). When you are looking down on the cam tower, you will see plugs where the towers are drilled for the oil galleys the feed the camshaft bearings. First off, you must be sure to insert the spray bar into the tower so that these cam oil galleys line up to the orifices on the spray bar for the cam bearing orifices. Secondly, you must make sure the spray bar aligns properly so that when you reinstall the bolt/locating pin at the rear of the cam tower aligns with the hole in the spray bar.

[Jim Williams]

Originally Posted by 911 tweaks

I just thought of another dumb question...when I remove the spray bar, in case it has become miss directed a/o wrongly installed, can you tell me where the spray bar holes need to be pointing, as in what/where should the oil be pissing on? the area where the rocker rides on the cam lobes?.
Bob

Sorry if this is a little late, I had difficulty finding these photos.

This shows how to line up the spray bar. Note the holes in the tube, and the chain housing plugs. The plugs cover the hole which was drilled in the housing to get oil to the cam journals. If the spray bar holes are aligned with the housing plugs and the end hole in the bar is facing outward, there is only one way the bar will fit properly.



Hope this helps.....

This way:



NOT this way:

[304065]

Single holes up, double holes down.

spray bar orientation

Jim, those are good pictures of the big holes that feed the cam journals.

Are those plugs in the holes that feed the journals? Or is that a vestigal casting boss left over from centerlube?

[911 tweaks]

thanks a lot everyone!! I will practice on a old tower first and see how it goes.
Many thanks here!!
Bob

[Walt Fricke]

Tweaks

Buy a 1/8" NPT pipe tap.

Buy 1/8" NPT pipe plugs. You can get them in iron, brass, or aluminum. I worry that aluminum plugs will be hard to remove (I had that problem with engine oil galley plugs), so brass seems a reasonable material.

To remove, drill a small hole that you can tap for a small machine screw. You aren't trying to drill out the plug, just create a way of grabbing it. And you aren't using your 1/8" tap either. You do have a metric tap set, right? And a junkbox with, say, 5mm bolts/machine screws?

I suppose you could use a slide hammer and your small machine screw. However, it is easy enough to make a puller. a) a socket or other short tube whose inside will clear the plug. b) a suitable washer or washers. c) a long enough machine screw. c) a nut for the screw.

Screw the nut onto the screw. Slide the washer on. Put the socket over the plug and insert the machine screw and screw it into the plug. Spin the nut down until everything is tight.

Hold the head of the machine screw fixed, and with a wrench tighten the nut. It should pull the plug out and into the socket. When things fall off you are done.

Maybe there are other, better, ways of doing this.

Walt Fricke

[911 tweaks]

thanks Walt! Your timing is perfect as always since I plan to tackeling this experiement tomorrow as long as the christmas party this afternoon doesent get out of hand if you know what I mean ;-). Power tools with a fat hang over head usually dont mix well.

I will p/up some brass plugs today and go to sears to use an old gift card and hopefully they have slide hammers. It is amazing that I have been buying tools for the past 30 yrs and EVERY fix-it or repair job could and probably would/does come out better/best AFTER I buy another new tool. What happens to the guys that dont proceed as I do? Maybe they are more lucky than I and or more talented OR they already spent the fortune on tools...

I will post pics of my hopeful attempts tomorrow on this doing.

Bob

[Jim Williams]

Originally Posted by john_cramer

Single holes up, double holes down.

spray bar orientation

Jim, those are good pictures of the big holes that feed the cam journals.

Are those plugs in the holes that feed the journals? Or is that a vestigal casting boss left over from centerlube?

John,

Those are definitely plugs in the holes that were drilled though to feed the journals...... Two such holes for the 4-journal cams, only one hole for the 3-journal cam housings.

[911 tweaks]

just received my plugs from mcmaster-carr.
1. I couldnt find from the thread whether to use the 6k psi steel plugs (shinney one on the right of 1st pic) or to use the 302 stainless steel ones?
2. The stainless ones were $0.50 ea. & the 6k psi steel ones were $1.05 ea.
3. I am also wondering which is the "stronger" metal so hex wont strip out? I don't recall being able to find a metal hardness spec but these looked like the best choices. The McMaster-carr part numbers are: Steel p/n 50925k231 & stainless p/n 4464k561
4. Which ones did you guys use and did you use any "goop" to prevent them getting stuck in cam tower so we can service the tube at a later time?
Thank you
Bob

[JFairman]

Originally Posted by 911 tweaks

I just thought of another dumb question...when I remove the spray bar, in case it has become miss directed a/o wrongly installed, can you tell me where the spray bar holes need to be pointing, as in what/where should the oil be pissing on? the area where the rocker rides on the cam lobes?.
Bob

It may be different on different years and models.

I have an '87 930 and the only cam spray bar holes I can see with the motor in the car are pointing straight up.
Alot of oil shoots out of them... I mean with a cold motor just cranking on the starter motor a straight 1/8" thick stream of oil will shoot about 6 feet or more straight up in the air...
With the rocker cover on the oil stream bounces/ricochets or splatters off the inside of the the top rocker cover which is angled in such a way that the oil then splatters all over the valves, rockers, and cam lobes.
There may be more holes in the spray bar that I havn't seen though.

As far as flushing the spray bars to remove small coffee ground sized coked oil chunks that clog the holes... (this is common on a turbo that has had dino oil run in it)
I've never removed them, but you can flush them out so easily while they are in the car by simply removing the 17mm plug at the firewall end of the cam tower and putting some polyvinyl or rubber hose into the threaded hole that fits snugly and running it through the air pump hose hole or any other hole in the engine pan into a container under the car.
Next use a pin to dislodge any carbon particles that may be lodged in a spray bar hole, then crank the motor over on the starter motor and alot of oil will flush through the spray bar taking any junk with it and out the hose into the container under the car.
You can start it and let it idle too. In about 15 seconds of idleing you'll pump around 2 quarts out the end of the spray bar through the hose and into the container under the car.
I still have around 4bar of oil pressure at idle with a cold motor while doing this so low oil pressure while doing this is not a concern.

Then take the oil that you have collected and filter it through something or just let it sit long enough for the carbon particles to settle to the bottom, and carefully pour it back into the oil tank watching for the carbon particles at the bottom so you can stop and not pour them back into the engine oil.

This process takes very little time and works very well.
Afterwards I slide the cleaned top rocker cover back on the studs and crank it on the starter motor for a couple seconds, then go back and remove it and check to see the 3 oil patterns on it where oil shot straight up and bounced off it.

Here's a pic of the clear vinyl hose I used in the hole, the 17mm plug with locating pin that goes in the hole, and the oil pattern on the inside of the top rocker cover while I did this a few months ago.

hope this helps.

[4sd911]

Ok, I'm attempting this on a damaged tower. It took me 5 stops at hardware and auto parts stores just to find brass plugs. You can not use brass it will strip the allen head long before the plug is flush, about half way in the plug gets tight. I've ordered some stainless steel plugs from McMaster. Threading the hole I tried free hand, not a good option, as it threaded at a bit of a angle. Do you use a drill press or mill?

[jpnovak]

NPT threads are tapered. You must tap deeper to get the plugs to fit both tight and flush. If your plug is tight before the plug is flush then pull it out and run the tap a bit more. keep going little by little until the plug is flush and tight.

[4sd911]

I got it, the tap is tapered not the plug (no I'm not a plummer). Successfully threaded and plugged the other side of test tower I moved on to an extra tower and threaded it also. I reamed the hole with a 21/64" drill bit and I used a port-align to start the tap. The threading leaves a burr at top I just used a de-burring ball to clean it. The brass plug could be used but if it gets to tight over time could be problem to remove so I'll use the stainless ones.

[911 tweaks]

smart move as I used the stainless ones too as I posted above...

[4sd911]

Thanks for posting that part number on the plugs, I didn't have much luck searching there site for the plugs.

[911 tweaks]

bag on the right...302 ss...good luck!
Bob

[khamul02]

Questions on a 11 year old post...

I'm thinking about using threaded plugs. Is using stainless plugs ok given the different expansion rates.. Several people have used them so at this point I would think someone could chime in.

If I go forward will these plugs and tap do the job?

https://www.amazon.com/Century-Drill-Tool-95201-Plug/dp/B004UUAMK4

https://www.amazon.com/Metalwork-Stainless-Steel-Fitting-Countersunk/dp/B07DDN298N

[WERK I]

Gawd, has it been that long already?

Regarding any application to the threads.....I would use an anti-galling lubricant and NOT a sealer. Sealer might migrate from threads into tube when installing the plugs.

Here's another site that may have what you're looking for...
https://www.mcmaster.com/

[khamul02]

Anti-galling lubricant such as?

[WERK I]

I used Permatex, Aluminum anti-galling , anti-seize lubricant sparingly. US Part Number: 80078

[911pcars]

Spray bar pipe plug at 3 o'clock:



It's a 1/8" NPT plug. The required tap drill is specified for the plug size. Can look up.

Sherwood