New motor, sounds awful?

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That sounds like something in the top end not getting oil. I just started a used 318 that has not run for a year. It sounded just like that until it got oil to the rockers. How long did it take for the first fire up, were you cranking a long time. like several minutes, than there is a chance the lifters are toast and cam will not break in correctly. Seems like your getting random cylinder misfires, this also could be caused by lifters not pump up. What rockers and style of cam are you running. Need more info on engine build. Also how long total has engine ran. If you think your having problems cut the oil filter open, cut section of pleats, squeeze out pleats in a vice, then look in between pleats for metal.
 
Maybe invest in a stethoscope, and try to locate where the noise is coming from. ( top end, bottom end?) also remove valve covers before starting. That might also help you out.
 
340Duster247 said:
Maybe invest in a stethoscope, and try to locate where the noise is coming from. ( top end, bottom end?) also remove valve covers before starting. That might also help you out.
Click to expand...

Or, grab that broom and remove the wood handle. it work real well as a stethoscope.:-D
 
A long screwdriver works too. Need to try and isolate where the sound is coming from.
 
The idea behind break-in is to properly set pre-load on installation. Start the car, get the lifters Pumped up and spinning in their bores with RPM's before they wear the lower diameter.

As the lobe comes around it causes the lifter to spin in the bore. Improper pre-load or tight lifters are a definite disaster. Polish the bores if needed

Also make sure the lobes are not centered in the bores. They must be off set to create more drag on one side to make them spin. A bad cam is not bad material it is improperly placed lobes. Cheap cams less QC. Same as Eagle parts. As long as you check your part specs before installation they're all good for use.

A loose pre-load is better then a tight one. If the pre-load is to tight the piston in the lifter will cover the oil hole and it will never pump up.
 
Here's an update on this saga.
The old boy rang me tonight.
After a two week summer Vacation (yeah, southern hemisphere for the win!) he's pulled the engine out of the car again. He said he had trouble turning the motor over by hand.
So out it came.
And as it turns out, one bank had the pistons back to front. It's running icon forged pistons, and they have one small relief, and one larger one. we can only assume that with the block being upside down, he got mixed up, and fitted the one side the wrong way around.
No wonder it sounded so hideous. So engine will be getting stripped down tomorrow. And the inet valves from that bank will be spun in the lathe with a dial indicator to see if they need to be replaced. (If i was a betting man, I'd say yes) As well as all other clearances wil be rechecked too.
Here's hoping that the valve guides haven't been split too. I'd say with the heads being iron, there's less chance of them having been damaged than in say the instance of a cam belt failure with an aluminum head..
 
I have seen this happen in a small Chevy once and the guy called me to have me come and lash his valves because the guy that built his engine couldn't. I never would have guessed it but the noise would not go away no matter what. They finally tore it down and found the pistons in the way yours are. I still can't believe the engine would even run with the valves making contact like that but it did. J.Rob
 
I'm actually glad we at least know what was wrong now.
We might have uncovered it sooner, but the pos crosswind sucked up a lot of time. (man, those manifolds are complete pieces of junk!)
probably have to check the pushrods are still straight too.
 
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