Camshaft Housing Removal Necessary?

[SP2]

Hello,

I am taking out my cams (81EuroSC) and will have them reground by John D. I had pitting on the cam lobes and John said they should come out. So I will regrind my rockers too. I will go with the 964 profile. I read today that I should consider cleaning out the oil squirters. I have my engine out of the car and was initially planning a reseal only until I saw the cams.

My question is, is it a big deal to removed the camshaft housings. Is this what I would need to do to clean out the squirters? Does the camshaft housing have a gasket, or is it just bolt on? I saw only pitting on one lobe, but some of the lobes were very dark in color. Very dark. (I posted pictures earlier.)

Thanks.

[MBEngineering]

HI SP2 if you have NO oil leaks from the cam housings then it should be OK, the oil spray bar can be removed from the back , by drilling the plug and taping m6 into the plug and using a long bolt with a nut, large flat washer and a m10 nut you can pull the plug out, the new plug is 901 105 379 00, you will need to remove the tin work on the L/H side and the oil cooler on the R/H side at the rear, or both chain cases at the front, up to you which end you go in ??, is the engine still in the car?, do NOT FORGET to remove the rear 17MM plug in the rear of the cam housing that locates the spray bar .

regards mike

[SP2]

Thanks Mike. Yes I have absolutely no leaks from the cam housing. When I pulled the left cam out last night it looked fine. No pitting like on the right side. I only have seen pitting on the right#4 intake cam lobe. The others that I can see with the valve covers off on the right are dark in color, like I previously showed.

So do you think it is even necessary to take out the oil spray bar? I am a little worried that your procedure is over my head, as I am a complete newbie to engine mechanics (but so far so good!)

[Walt Fricke]

The best way to get around newbiness is to buy our host's book on rebuilding the 911 engine. Don't rely entirely on the kindness of strangers over the internet.

I'd pull the spray bar. You stated the case for doing this: one cam looked fine, the other looked bad and maybe even overheated. Unless this engine had some kind of hack rebuild in its past, there has to be a reason for this difference. And an oiling problem is a reasonable place to start looking. That means the spray bar, most likely.

I think you would find all this easier if you would take the cam carrier off of the heads. Once you have all those rockers out, and the cam out, you have done 95% of the work of getting the carrier off the heads. You will need some orange loctite or other suitable sealant when you put the carrier back on at the end of this adventure, but it is good to get your feet wet doing this.

After inspecting the spray bar and seeing how and where it is held in, and the end plugs, reread the post you were given on drilling and tapping a hole in a plug and pulling the plug out. If that still doesn't make sense, maybe take the cam carrier to a mechanic or machine shop and discuss having them do it for you. And doing the tricky part - replugging it.

You can check the spray bar in the cam carrier by spraying brake cleaner into it and then applying compressed air and looking (carefully) and feeling for where it comes out. I put fingers over two of the three big cam bearing holes when I do this, which helps direct the spray out of the small holes that spray the rockers and cams. But this won't get out any particulate matter that may have gotten into the bar if it has hidden down at the far end.

Walt

[SP2]

Thanks Walt,
Yes I have both of Wayne's books. They are my bibles now. I think I will go your route. Mike's makes sense of course, but I am more confident in torqueing down bolts. I am afraid I might screw up the replug. Your comment about "95% done" makes me feel better and I think I will unbolt the housing and take it to JW to professionally inspect for me. There is no substitute for experience, something I am waiting patiently to acquire.

I am fired up now. Looking forward to working with the orange stuff.

[MBEngineering]

HI James as long as the old plug is removed OK then re plugging is as easy as hammering in a nail as long as you use the Porsche plug, if the cam carriers are not leaking i would leave them alone, just make shure that you make note of the positioning and which end is fitted to which end as the pipe can be fitted either way round and half a turn out, I have photos of the tools you require and the plug, hope it helps .(from a stranger over the Internet, with only a few postings on hear). regards mike

[MBEngineering]

HI the photos, regards mike

[SP2]

Wow, thanks Mike! I have a friend that is a professional mechanic, Ognian, and he may have these tools. I will show him this thread. I will do this after the holiday. We have this thing here about the pilgrims...

[MBEngineering]

HI James if you cannot get any plugs drop me a PM with a shipping add and i will pop some in the post.

regards mike

[SP2]

Thanks Mike. I am sure I will be able to get the plugs. Thanks for the part number and the photos!

[SP2]

Hi Mike,

I got the spray bar out. I modified your instructions a little. I was at John Walker's and asked him about the tap, etc and he suggested to use his technique of putting in a machine screw. So I drilled it, put in the screw, and then pried it out.


The I grabbed the bar delicately with pliers cushioned with a rag so as not to pinch/damage the bar. My intake rocker #5 was very badly pitted. I didn't realize it until I took it to Delta Camshaft, so I didn't get a picture of it. So I was wondering if there was dirt plugging up that part of the spray bar, but the inner spray bar was clean. But the second photo shows this big stain. It was some type of adhesive and very difficult to clean off with scotchbrite. I am wondering if it covered the big hole, impeding flow. But I think the big holes are for the bearing journals on the cam, right? I am not sure if this "stain" had anything to do with my camshaft being so black and dirty on this side and pitted on the cam lobe of #4.


So Mike, how do I put it back together when it is time? Do I lube the bar? I figure I will lube it with clean motor oil. The porsche workshop manual says to replace the plug, I need to lube the plug and the hole, then apply an adhesive. Is this what you do? Thanks!

[MBEngineering]

HI James just push the bar/tube in, if there is any resistance pull it back out, DO NOT FORCE IT IN it will jam , but first check it is the correct way round and facing the correct way up, the mark on the bar/tube is ok , do you have any tube brushes to clean the in side of the tube , and then check the holes are clear with solvent/cleaner, when you have the bar/tube fitted and locked with the end plug/screw, if you are happy it is in correct then, the porsche plug is just fitted with a hammer, with no sealant, I have fitted a few now and no leaks .

regards mike

[SP2]

mike got message. no power in seattle 2nd to storm, but got mess. by phone. thx!

[A930Rocket]

Is there only "one" way to orient the spray bar? I see that the large hole in the end of it must line up with the oil line adapter and banjo bolt.

[SP2]

Originally posted by A930Rocket
Is there only "one" way to orient the spray bar? I see that the large hole in the end of it must line up with the oil line adapter and banjo bolt.

Rocket,

That hole you see at the end, well there is another at the same end, 180 degrees around. So you could line this hole up with the bolt, but the little holes won't be aimed at the rockers and cam lobes.

[MBEngineering]

HI and do not forget the oil feed to the cam bearings as the bearings are NOT evenly spaced, so the wrong way round and 180 Deg rotation is not good, no oil to the center cam bearings and no oil to the inlet rockers, small amount to the exhaust.

regards mike

[A930Rocket]

Good info guys. Thanks.

[kepperly]

Is this feed from the cam tenioner line that has the restrictor
plug recommendation??

Keith Epperly
87 slant nose turbo look carrera cabriolet

[SP2]

Yes it is.