First engine drop
 

Bought my first 911 (1976 Targa, 2.7L and weber carbs) a couple of months ago from a fellow pelican in Mass. Drove it back to PA without incident. Noticed it leaking a little oil once I got it home and over the next month the leak went from a few drops a day to a few cups a day. I'd let the car sit for for a week and it looked like a lake of oil on the garage floor. It looks like its coming from the right side cam seal. Thats at least my best guess after spending a lot of time under the car cleaning and watching. I think I've got about all the special tools I'll need to change the cam seal: 46mm crows foot, P202 socket for cam and Z-Block w/dial indicator.

Here are the obligatory pictures.

Pic of car as it was a few days a ago (pic from previous owner).
http://forums.pelicanparts.com/uploa...1251742564.jpg


In the engine bay.
http://forums.pelicanparts.com/uploa...1251742851.jpg

One of my pit crew.
http://forums.pelicanparts.com/uploa...1251742912.jpg

Over the next day or so I'm going to just crank the engine by hand and try and thoroughly understand the cam timing, use the Z block and adjust the valves. Do I need a racing type mechanical tensioner to re-time the cam?

BTW, I still have the old style tensioner, at least they have safety collars installed.

Any advice from the experts here would be greatly appreciated.

Bob

dont have any advice but ..

great looking car.

Since you weren't able to completely isolate the oil leak and you're new to the car I would replace all the oil gaskets and seals. Remove the oil cooler, flush it, change out the oil return tubes seals, you've already done all the hard work getting the engine out. Take a little extra time and be sure that everything is up to snuff in the engine room "while you there"...

Good looking son...

when i bought mine, it had a hellacious oil leak, I picked it up in Atlanta, and as soon as it hit the garage, i pulled the engine, and found that the O ring on the Oil thermostat was petrified. I went ahead and replaced the breather seal, and the oil cooler o rings. all of these are common problem areas for the 911, so you may want to address them since the motor is out too. Nice car man, and its good to see that you are tackling it with your son.

Welcome to the forum.
Nice car!
Congrats on the engine drop. ( hoping to do my first soon as well)
Upgrade to late style tensioners, it's a must have upgrade.

Is that a metal lid with a ducktail on it?? Is it an original item??

The tensioner guards will do the job unless you have almost $500 burning a hole in your pocket and absolutely no place else you can spend it
Bruce

Nice car!

If you use the search function on "Carrera tensioner", you will find A LOT of discussion about the pros and cons. I personally landed on the side of using the oil fed tensioner but have rebuilt and set aside the old failed mechanical tensioner removed from my car.

The collars do nothing more than provide a little safety during the time the mechanicals are failing. In my case, the P.O. installed the collars. The tensioners were so bad, one of the collars broke and went into the sump screen. I would look closely at your collars. If the faces are scored or scratched like they have made significant, repeated contact with the tensioner body, consider rebuilding the mechanicals or upgrading to the oil fed units.

Yes, Carrera tensioner are expensive but, IMHO, worth it. The collars are next to useless. Also, look at replacing the chain ramps. Ramps are cheap and easy especially while you have the engine out. You could probably assign their installation to the assistant.

I'd like to do the Carrera tensioner upgrade at some point but its not in the budget right now. I know that the cost of the upgrade is small compared to the cost of the damage that can happen if the old style tensioners fail but its going to have to wait a bit for now.

As to the duck tail, its not original. I do have the the original engine lid if I want to go back to the stock look but I like the tail. I'm not really a big fan of the targa look in general but for some reason I really like this look, I don't know what it is exactly but it just works. Also, my wife and kids get a big kick out of driving with the top off.

I've spent a lot of time under the car trying to pinpoint the oil leak. Since the car has carbs I can easily see most of the common oil leak points. I also got a big stack of documentation with the car and there are a bunch of Pelican Parts order forms from the previous owner and I can see that he replaced all of the most common seals. I might blow out the oil cooler just to do it but I was able to verify that all the other common leak points are dry.

At first I thought I had 2 leaks, one at the front of the engine and one at the back because I was seeing 2 puddles of oil. But, its all coming from behind the chain case. Its just that some of the oil would drip down below the chain case and some would run down the heat exchanger and drip off near the oil cooler. For a while I thought the oil cooler was also leaking but its really dry. I later discovered that the PO had already addressed an oil cooler leak with new seals and performed the JB Weld fix to the case.

I'll post some pics of the cam seal job as I go. I'll post a new thread if I really get in a jam and need some help.

Thank you all for the kind welcome,
Bob

Hey there! Just saw you're avatar photo and said I think I know that car. You are on the right track on the seal - that's the oil leak I had told you about - drive it a few times a week and all is OK, a couple drips let it sit longer the oil gets into the case and finds that seal.

A trusted mechanic up here said that eventually they all leak there - the older seal shrinks and there's not much you can do about it.

You are right though - thermostat o ring, oil cooler seals, a couple case through bolt o rings under the cooler, breather gasket, chain cover gaskets were all addressed. The trombone was flushed when I had gotten it used and the elephant lines and external thermostat were new when I decided to add the external circuit.

Hope you've been enjoying it up to this point and everything is as expected.

The JB weld area is a spot where there is something going through the case that can weep - I found mention of here on Pelican and did the recommended procedure just in case. When searching for that elusive leak I had replaced all the common causes up top, then the cooler seals, then the cooler with a known, tested cooler, then discovered it was the 'o'rings behind the acorn nuts that are behind the cooler. That leak would drip from the bottom of the cooler when the motor was running - drove me crazy for a bit but had been leak free for a couple years.

Dean, good to see you are still surfing the 911 boards. I sent you a PM.

To everyone else, I got as far as spinning the engine a 100 times to be sure I totally understood how to measure the overlap before breaking the big cam nut. I found the big pressed stud for the tensioner really loose. I was able to get the housing off (right side) with HE and chain still on. Found a used chain housing and expect to receive it in a couple of weeks. Its been pretty straight foreword so far. I'm bitting at the bit to get the housing and get the engine back in to enjoy what is left of driving season. What could be better than fall in the north east and a targa top.

I have that EXACT leak and was a bit intimidated in timing the cams, i even have the gaskets and seals I need. ... I will be watching with close atention for sure

theiceman, do a thread search for cam timing question, I posted a bunch of pics detailing how I was reading the valve overlap. I wanted to be sure I was doing it right before I broke the big cam nut. Its not so hard to do but you keep thinking about all the bad things that can happen it its not right. I'll be updating the cam timing thread, with pics, once I get my replacement chain case.

will do thanks .. I think we are thinking along a similar vein. i keep thinking is the risk worth the reward. I am leaking at both sides as i see the trail of oil running down the chain box between the box and the cam tower so i know we have the same leak. Mine does not leave puddles however , just a couple of drops. I didn't think there was enough oil up there while standing to have the puddle of what you decribe. but i guess the proof is in the pudding.

PS maybe I missed it but why are you replacing the chain box ?