Engine problem 911 2.7 1976

[fdeville]

Hi, I'm starting to rebuild a 1976 911 targa, 2.7 engine. The numbers are matching but that's about all that is still good about the car. But I love it and I know that is will take time and effort (and $$$) to bring it back to live.
I already did a few things before now starting the serious work: the engine. It is losing oil (they all do), but it is not running well at all. It makes a kind of 'clapping' noise. Difficult to describe so I posted a short video on youtube where you can crearly here that there is something seriously wrong. So I already know that I'll have to take the engine out of the car to have it rebuild, but does anybody can 'guess' what the problem is that causes this noise ? So I know a bit more in advance how bad it is...
Link to the video:

Edited February 22, 2014 by fdeville

[Loren]

Inspection and a tests are needed to further diagnose.

I suggest both a visual inspections (locate the oil leak) a compression test.

Those engines are prone to head stud failures so look for oil and loss of compression on the cylinder with the broken stud(s).

[fdeville]

Hi, so based on the sound you think the problem would be a head stud failure ? Is there an easy way to check this before removing the engine ?

Edited February 22, 2014 by fdeville

[Loren]

It's hard to say - did the last owner run it without oil? did they let it over-heat? You just don't know without further inspection on a lift.

Why would you remove the engine? -- you need a visual inspection and compression tests. Both can be done without removing the engine.

Many head stud failures can be foxed without removing the engine.

[fdeville]

Ok tx, so first thing I will do is a compression test & visual check. I'll post my findings here.

[Loren]

Look at where the head studs go into the case - look for oil where they go into the block and sometimes they are so bad you can move them with your fingers.

[Dr. Wood]

Sounds like a rod, your gong to take it down to the crank anyway.

[mjourney]

noise sounds up top. maybe even front I.e. CHAIN TENSIONER ? Also sound exssive valve lash; scored camshaft / rocker due to oil spraybar clog ? Pay attenntion as you have start at the top front any way. Good luck, and don't fix what aint broke unless you know from experience or what you see is what you got. MJ.

[mjourney]

I listened to again . And yes it sounded like a Con rod . You can use a long shank screwdriver for a poor mans stethascope to help isolate the noise! M.J.

[quattroman]

1. definitely a rod knock, don't run the engine more than you have to or rev it up. If it lets go it's catastrophic!