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Engine clacking at 4k rpm.

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What I saw and heard from the video is a motor not getting enough (or any) oil to the rockers. You said you had recently had the head off. If the oil hole in the block/head/head gasket is blocked, or if you diddled with the rocker shaft.... Only one rocker tower has a hole to guide the oil from the top of the head to the rockers. If you disassembled the rocker assembly and reassembled incorrectly, the oil supply rocker tower may now be in the wrong position. You would have great oil pressure, find little oil puddled on the top of the head after running the motor and the rockers will get louder and louder with every minute of operation. Sound familiar?

Glen Byrns
 
That's where we're headed with this.

Where'd you get that head gasket, Barry? Rather; what "brand" is it?
 
Glen_B said:
You would have great oil pressure, find little oil puddled on the top of the head after running the motor and the rockers will get louder and louder with every minute of operation. Sound familiar?
Click to expand...
Guilty as charged. I'll take a look at that assembly again. What irks me as I went through great pains to ensure that the rocker assembly went back on as it came off. I honestly can't see any other way that it could go back on with the same rods etc....
Anyhow, I'm looking for the oil passages, which rocker tower, I would guess #1?
The rocker innuds, shaft etc was not dismantled.
 
DrEntropy said:
That's where we're headed with this.

Where'd you get that head gasket, Barry? Rather; what "brand" is it?
Click to expand...

I did post a question here regarding this head gasket, because it had no identifying marks, such as TOP, FRONT or such, and no difference in texture either side, hence the reason for my question way back when.
As a result, I have no idea what 'brand' it is, but suffice it to say, I think you all already know I got it from....

Well, Payens were unavailable..... /bcforum/images/%%GRAEMLIN_URL%%/blush.gif
 
Start with a really good examination of the shaft/rocker assembly. I'd be for removing it and completely disassembling and thoroughly cleaning it... keeping all components in order. Look over the head, the pedestal base on the head with the oilway should be obvious; make sure the corresponding pedestal is mated to that. It could be as simple as wrong pedestal over the oil passage... if you didn't disassemble the shaft ass'y mebbe it's been this way all along?

...just musing.

If it goes as deep as the head gasket, NAPA should be able to get Fel-Pro gaskets for you.
 
I just ordered a Payen set and other bits and bobs and I'll attack it again this weekend...
A) With the rockers off, should get a diagnosis, if not...
B) With the head off, should get a diagnosis.

I suspect the head gasket is obstructing something personally.

One more thing, which NGK (#) plugs are the recommended choice?
 
The Champion ones... /bcforum/images/%%GRAEMLIN_URL%%/devilgrin.gif


...couldn't resist.


I *think* the BP6ES, but it's been a while.
 
Did ya see the pic in thisy here thread???
Champion plugs, 125 miles, they break!

I'll snake the ones in the B.
Dirty Champions are better than new Bosch.
 
meh. For whatever reason the Bosch Plats are great in the Alfa, last what seems MINUTES in the B... Champ's are just the reverse.

...perverse, innit? /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif
 
Please take a look at this photo, particularly at the rocker pedestals....
From all the diagrams, exploded pictures, etc from all the books I have, suggest there should be a hole between the two nuts in the center of the pedestal. I only have one hole, I believe a grub nut, on #2, diagrams suggest this should be on #1.
Anyhow, if anyone can see anything anatomically incorrect, please let me know.....I'm still looking for oil paths, but I can't for the life of me see where they are.
b6959360535d04ce095621fc751408180_large.jpg
 
Baz said:
I'm still looking for oil paths, but I can't for the life of me see where they are.
Click to expand...
Here's the "DOH!!!" moment.

I can't find them because they're blocked from view. The shaft has holes in that are ~supposed~ to coincide with the holes on the inside of the rocker pedestals right?
Well, there's my problem!
a) #4 doesn't coincide, hence the clacking there.
b) grub nut supposed to be on #1, not #2 (DPO).
c) I don't have ANY bracket plates on the tops of the pedestals.
 
I'm at work now so I'll have to go from memory, but, the grub screw is on the second tower to align the rocker shaft. The correct alignment is crucial to create the correct oiol passages. The cap/washer plates have a slot that will (on the #2 tower) lock this grub screw. The oil passes up through the head into and through the #1 tower to fill up the rockershaft. From your photo, there is serious heat discoloration of the rear part of the rocker shaft and rockers. You should check the rocker gear very carefully for wear. All things considered, I imagine its shot from running without enough oil.

Glen
 
I must agree with Glen about positioning and functionality of the towers. That is correct. I can not however confirm the heat discoloration, though it does appear darker in the picture. It is likely though that it has been worn from lack of oil.

Do us a quick check. Pull the plugs and rocker shaft. Crank the engine and see if oil comes out the oil supply hole under the #1 tower.

If yes, head gasket ok.
If no, head gasket not ok.

Plain and simple. (We are assuming there IS oil pressure, I couldn't see it on the videos.)

D.
 
Thanks Donn. I did the test.
Yes, there was oil emerging from the hole at #1, however it was more of a 'blob' than I expected, something like the start of Beverly Hillbillies. Oil pressure (on the gauge) did come up during cranking.
I did get video, but a blob is a blob.

That being said, enough to get through the thinner holes and all the way to #4?
Much thicker than I thought, perhaps I could switch blends to a thinner viscosity when all said & done.

Thanks Glen for your comments, I won't give up on her just yet!
 
When you pull the head, be sure to photograph the head gasket as it still sits on the head, that should be educational!
Then blow through the oil hole on the underside of the head and be sure that a stream of air moves easlily through the head and out the other hole. Once the rocker towers were off and the engine was cranked, there should have been a large gushing of oil out the hole, NOT a slow Beverly Hillbilly seep. With such a relatively large open hole in the oil delivery system, the oil pressure when cranking should have been nil or low.

Glen
 
My head gasket should arrive tomorrow, so tonight, I'll reassemble the rocker & shaft.
Pull the head tomorrow morning, maybe, if all goes well, have a new gasket on there and started back up by evensong.

When I pulled the rockers off, I discovered filings. Thousands of tiny grains of filings.
 
Can't stop the momentum....
Coolant out, totally missing the collection device and gushing on the floor. Whatever.

Is there a way of removing the manifolds from the head without going through the whole pulava of removing cables, carbs, spacers, heat shields and all that stuff?

I just want the head off.....grrr OHV /bcforum/images/%%GRAEMLIN_URL%%/mad.gif /bcforum/images/%%GRAEMLIN_URL%%/mad.gif
 
Sorry,so sorry....
Those 'filings' are the remains of the rocker bushings. You may want to replace the entire rocker assembly, as oiless destruction of the bushings will certainly have scarred the rocker shaft. A good look at the valve stems and a close evaluation of the valve guides would be a good idea at this point. Extending the logic, the lifters and pushrods deserve a close look as well. The whole upper end has been run nearly dry long enough to cause damage and possibly distribute metal filings in the neighborhood.
This has got to hurt. I feel your pain. I just opened a box with two replacement pistons that don't match the originals from the same custom piston maker. My repair job just took a one month hit.
Glen
 
Its best to remove the manifolds, otherwise twill be all weighted on one side and difficult to get back down easy. My advice, take off the manifolds and tie them together with wire ties to something to hold them in position and leave all cables attached and exhaust pipe to the manifold. find a board or something to run from the pedal box to the hood latch panel to tie too. Remove the head and gasket and take some single edge razor blades and scrape all surfaces to remove any residue of old gaskets, etc. Then put it back together.
 
Thanks guys.
I'm walking away for a day or two, tend to the garden, weave a basket; come back to it when I have a clearer mindset.
The rocker assembly is actually in good shape, the holes were indeed aligned, grub screw did its job, springs good, pushrods and lifters all look OK. The shaft too, slides nicely with no friction, so I'm guessing this is an oil delivery problem.

I shoved a piece of copper wire, then a toothpick down to hole and it met some resistance about an inch down.

I need to play some 'Doom' or something.
 
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