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Engine clacking at 4k rpm.

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Go blow something up (digitally speaking, of course)... you'll feel better. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
Pull the head, just remove the exhaust and intake bolts and move the whole assy to the side.

Take the whole head to a machine shop and have them cook it and make sure all the oil passages are clear etc. Good time to have valves ground and new guides if they recommend same.

Do take pic of the head gasket.
 
The head just came back from the machine shop 125 miles ago, new guides, valves, springs, 5 angle grind, lye bath, the whole bit.
Fear not, that head gasket, if it as to blame, will be booked, finger printed and placed on an offender registry.

How about one of these bad boys????

c-aht446.jpg
 
The high lift rockers are fine, though a little pricey. But remember that 1.5 rockers don't fit under the standard valve cover. You must go to aluminium.

I got a set of 1.3 bushings from APT https://www.aptfast.com but they need reaming with a 9/16 hand reamer. If you don't have one, like I didn't, they are available on ebay sometimes for about $5. The bushings cost $6 each. A new shaft costs $30.

Now the hard part...
Engines hate metal filings. Clean up all you can from on top of the head (easy with the head off) and flush out the engine oil. (I guess it isn't that hard)
 
Pulling a cylinder head at 5:00 AM ain't fun.
Anyway, it's off.
The gasket is intact and matches all the holes that are on the block and underside of the head...
The head # is 12G1316, the block is a 12CJ, so I guess they match.
I identified the oil hole (singular) as being the furthest forward left hole. I poked my copper wire in it, it comes out of the hole at #1 rocker. Poked my copper wire into the block side, it goes what seems forever, in both cases, with oil on the wire.
I guess then that my oil path is free.
Suggestions or thoughts on.....
Oil pump?
Strainer clogged?
Sludge?

pics shortly....
 
Pics...I see nothing untoward, but let me know what you think about the colour of the underside of the valves on #4.....
5f6a58186ca375450ce91cc7b7bb9cbb0_large.jpg

3d94780193a2286a3989e9c3f9c0caba0_large.jpg
 
Color not a prob but she was surely running rich.

Try air pressure through those passages as well.

If your oil gauage was correct, and I have no reason to suspect otherwise something is blocking something someplace.

And yes I would replace the oil pump.

Hay guys can we turn the pump somehow without running the engine? I mean without spinning the crank. Can't think of a way to test this.

Gesh, is the oil strainer clear? So many things. Guess I would pull the engine and boil it out but then that's just me. Then would replace with new pump and what ever else I thought needed to be renewed. I know is a real pain but so is a fried engine.

Maybe the racers can comment but I have never had a pump quit, in fact I have never replaced one. Nothing really to wear out and it does run in oil.
 
Thanks Morris, my Payen set should arrive today.
I'm fairly resigned to pulling the motor here Jack, perhaps at the very least I can drop the sump and inspect the strainer, scrape out some tar or sludge. I guess the oil pump works because oil does move about.
I'm pretty sure the pump works off a drive from the cam.
10W40 might be worth trying as well.
Got too much invested in this car to quit, and a clogged strainer or something trivial like that isn't going to stop me.
 
Pump drives off the back of the cam yes.

Again, if it was my engine with that kind of a problem I would pull it and rebuild as necessary with an extra good boil out at the machine shop. No since haveing a nice car and a motor you wonder about. But then maybe that's just me. Cost is no object Jack, well not really but priorties you know.
 
I'm far too conservative to be yanking motors!!
I thought I'd give this a try today...
Replace gaskets and head, put some cam lube on the rockers just for starting purposes. Go to my local parts store and buy some of that engine cleany treatment STP stuff and run that stuff in for 15 mins or so.
Change the oil and oil filter.
Take the plugs out and the rockers off and do that cool test with the Beverly Hillbillies blob.
If it gets better, excellent, if not, I'll drop the sump, clean the strainer and the sump, any better? Yes? Good!
If not, I'll pull the motor.
 
Since there was some oil coming through some of the rockers,but the heat and noise came from the fourth pedestal area, is it possible that the oil hole for the last pedestal is plugged?

Those fancy Titan 1.5 rollers don't fit well under an aluminum rocker cover either. Mine are coming off to return to 1.3 stock. On a turbocharged motor they didn't increase HP one little bit.

Glen
 
It came up eventually, but still came up as a treacle-like thick blob.
That rules out any head blockage.
Each time cranking, I let the pressure come up to about 62 where it stayed, just a blob.
 
That may not be a problem, Barry. It shouldn't look like Vesuvius. You're going to get pressure, not volume thru that passage. The valvetrain doesn't need much to stay lubed. If the rocker shaft was fitted backwards (as it seems from your prior post, above) and the pedestals junxtaposed, the oil wouldn't be going where it should... You may not have needed to pull the head /bcforum/images/%%GRAEMLIN_URL%%/frown.gif
 
Vince is sending me another (OE forged metal) rocker assembly.
I'll reassemble my motor, then use his for comparison.
I do feel a bit better about having a Payen on there, and I'm fairly convinced this is a rocker issue.
I want to see the anatomy of his to see if there is anything missing on mine, such as a shaft plug, a bracket, a bushing or something that would disrupt the natural flow of oil away from #4.
A thinner oil for a short time might make me feel better also, if pressure, not volume, is the key, then it could flow a little easier.
It's tinker time!
 
You're on the right track as far as diagnostic paths go. One exception for future reference. Someone's got it backwards and passing it on.

Volume is the key, pressure is secondary to volume for ANY contact bearing loaded surface.

If you doubt that, then why do a lot of the motorcycles built now come with low oil level warnings, not pressure warnings.

You're not gonna have volume without sufficient pressure, but can have 1000 lbs of pressure spitting through an orifice the size of aneedle eye and it does darn little.
 
I may have under-explained it: the pressure is going to be there. Enough to KEEP appropriate volume flowing. The size of that passage is designed to allow enough volume, it apparently just wasn't getting to the right places due to DPO juggling of the rocker shaft components. It doesn't look like much when allowed to just "puddle" from the passage, but when distributed appropriately will flow from all the orifices at the proper places with the same rate to lube the valvetrain.
 
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