you havent put an oval port head on the a12 have you. If you have then you need to redrill the oil hole in the head or no oil can get to the rocker gear and it will run dry and sqeeeek. To check if its that all you have to do is put some oil over the rockers and see if the noise goes away.
good luck
olboy

Quote:

Good chance this could be your problem......

Could also be as simple as the tapered long head bolt (this bolt forms part of the oil gallery to the head) is in the wrong hole. it goes in between cylinder 2 & 3 , could be either side depending on which version of the A-Series it is.

Do you have any other pics of the engine apart ?....in particular a shot of the deck of the block without the head. then you can tell if the long bolt is in the right hole. By identifying where it should go.........

Benny

O.K. click on the link in my signature to view my car - there's loads of photos there of the block and head etc.

There was one bolt which was much longer than the others and the only place it would fit due to its length was the middle bolt on the dissy side of the block (from memory). I used a set of calipers to measure the depth of each bolt hole and put the longest bolt in the longest hole.

Also - every bolt I had was tapered. They were all of one thickness for the first inch and a half or so - and then thinner by a millimeter or so for the rest of the length.

Sorry, counldnt quite find a pic that was large enough on your web site, to display the deck of the block close enough.

Couldnt define the head bolt holes clearly enough.

Benny

I've got much larger copies of those if you see one that might help I can post a bigger version.

I checked over my larger images and found that the bolt hole in the head and the matching one on the block between cyl 2 & 3 on the dissy side was black but every other bolt hole was brown and dry like water galleries are. I conclude from this that the bolt hole in the middle on the dissy side was the one carrying the oil to the head.

Now can anyone tell me if I used the right bolt for that hole. I used one that was longer by 20mm or so than all the other ones.

Someone gave me the head bolts in a box when I bought the motor in pieces so I assumed that the odd one out was the one that allowed the oil to flow. Also as noted earlier the hole mentioned above was also the only one long enough to hold the longer head bolt.

The horrible vibrating noise was the internals of the PCV valve. Seeing as my carbs were very badly out of balance something wierd was happening through the manifold balance pipe which is where the PCV is situated. When the engine was running near a 1000 RPM (lumpy) its internal disc would chatter about. I verified this by clamping the hose shut and the noise stopped.

I have since managed to get the carbs properly balanced and idling smoothly and the noise no longer happens.

Wierd but at least I have an explanation for you all.

thank goodness for that....................who would of picked it.