May have trashed the cam and tappets.

 

Sounds like "automatic rough" on a Cessna 180. Automatic rough would engage whenever flying a wheeled single-engine aircraft over water. Miraculously it would cure itself whenever a safe place to land came within gliding distance. Are you sure there's a knock?

 

That would "suck" to have to put in a new cam. Of course then I'd just have to go through the whole thing, and that WOULD suck.

 

Could it be the oil pressure relief valve hammering, it's right on the filter head perhaps try listening with a stethoscope. My thinking is perhaps the 6 qts became a little gummy and plugged the filter then just topping off disguised the problem. If it was me I would drain the oil through a fine filter and take a sample. The sample is to see if there is anything in the oil not visible, any larger bits would show in the filter. If there is nothing in the filter I would then change the engine oil filter and refill using a full synthetic 5W40 diesel oil specified for our engines, then send out the sample for testing. Good luck

Oh the Cessna 180 thing.. like they say "anything with a prop.. belongs in the water anyway"

 

Well, we adjusted the valves and found the intake on #1 was out .010. Not sure on the others but it ran quiet for about 15-20 minutes and started rattling again. I think it's time to pull the engine and see what's inside. I'll look at the bottom end while it's out. It's got 272xxx on it right now. I know the head has been off and it had a new turbo installed just before I bought it, but I don't know if they touched the bottom end. Time to get a game plan.
What are your reccomendations? I don't plan on making over 600 hp in the future. I have my 39 Ford to take care of my needs in that department. This is a daily driver that does occasional towing in the 8000-16000 range.
I have been looking at a Colt Stage 1 cam, still not sure though.

 

No doubt, a Hamilton 188/208. I love mine. Just grossed 21,000 saturday. Pulled great.

 

No way I would pull the engine without seeing the results of an oil analysis first.

I have 'fixed' many engine ticks by getting the engine up to operating temperature, draining the oil and adding enough Rislone to keep up the oil pressure. Then let the engine idle for maybe 20 minutes. Drain the Rislone, install a new oil filter and regular oil and in almost 100% of the cases, no more ticks.

Yes, this works on 180's and 185's too.

 

I agree, ANYTHING seriously wrong inside is going to show with an oil analysis, and most impending failures that came up as quickly as yours will show in a filter if you drain the oil through one.

 

I have a place down the road that should be able to do an analysis. Also thinking of running some Marvel Mystery Oil in it for a short while to see if something is gummed up. Think I'll wait until I get the analysis done first.

 

Yup, get that oil analysis done ASAP. It is like doing a blood test and xray before going in for surgery. That way the Doc isn't in there digging around for fun. No need to do brain surgery if it is your appendix that is busted.

 

Perfect way to describe it!!

 

That would have been helpful last May. I went in to get my knee scoped and apparently they did a lobotomy. Going to head home and let some oil out for the sample.

 

Ooops sorry

 

Got the oil sample ready to send out. Won't know about that until the end of the week. I brought the RPMs up to 1500 this evening and used the stethescope to isolate the knock. 4, 5, and 6 all had the knock, it got progressively louder the farther back I went. I took each reading with the probe on the exhaust manifold bolt.

 

the reason why you didnt hear any noise is because there was just enuff oil in it for the oil pump to pick up and coat the rockers with only six quarts in it where it needs 3 GALLONS! the rod bearings r toast especially after a hour long journey.