Thanks to all that have posted in this tread about Ceratec and hexagonal boron nitride to be more specific. At this point brand names and price is of little interest but quality and price will become a concern when and if I decide to use it in all of our engines.
What started my search for newer type additives that lead to info on the hexagonal boron nitride was the 16 year old son and I bought a GRAY 2002 Polaris Magnum 325 ATV with a known blown engine due to the owner blowing an oil cooler hose and riding until he heard it hammering going down a paved road.
We have another ATV (Green)that is of the same 2000-2002 Magnum 325 era but it turned out the chassis on a 2002 with the blown engine (would idle fine but knock and die if given gas). Since the son needed some wrenching experience I decided to make it a shop project. We were able to pull the connecting rod without splitting the crankcase by working through the jug hole.
It had a totally spun rod inserts, trashed rod and a sick crank and some light cylinder/piston scoring with the cam still in spec. Cold compression was 95 PSI with throttle open after 5 compression strokes using the starter motor.
To keep our training parts cost low we put it (Gray) back together buying only new rings, rod bearing inserts and top end gasket set plus a used connecting rod for a total of $120. We worked to remove as much rod bearing material from the crank as we could by hand working though the jug hole.
Our first two objectives were to prove or disprove one can pull the rod and replace it without cracking the crank case because our research did not turn up a way it could be down. After we proved it could be removed we wanted to see if we could manually clean up the crank and put it back together and get it to run.
I was totally caught off guard by advances like using hexagonal boron nitride in engine oil. I was thinking about cubic boron nitride which is a diamond like abrasive I guess.
We have put 11 hours of idle time on the Gray 325 Magnum engine but not ridden it yet. At idle there is no knock but I hear some knock if I briefly hit the throttle but those engines knock a lot from new. It has good power and will rev high quickly. With my tool and die background I never expected it would have held together for 11 hours due to the damaged crank shaft rod bearing surface and expect it may be out of round a bit from prior damage.
After reading this tread I came up with four bottles of Liqui Moly Ceratec which we premixed per the label (2 oz per quart of oil I think) with Mobil 1 10W-40 High Mileage before we put it in the crank case. With the spark plug out we bought up the oil pressure several times with the starter and watched the oil come out on top the cam through the intake valve adjusting plug hole. Then we put in a new OEM spark plug and started running the engine expecting it to fly apart.
For our lab control in the Ceratec evaluation we did the same with the Green twin ATV by replacing the rings with matching brand used in the Gray ATV with the damaged crank and replace the rod bearing inserts with the same OEM inserts used in the Gray one and a new top engine gasket set and spark plug. Its crank and rod bearings looked new like. As with the Gray one we filled it with the 10W-40 Mobil 1 HM oil except with NO additives. It has been started and ran 15-20 minutes but its carb that I had rebuilt was loading up really bad I want to check out why the carb is loading up before we wash the new rings with gas.
As a recap both 325 engines have new rings, connecting rod bearings and top end gasket sets with the same motor oil. The Gray one got the Ceratec trying to see if it will coat the damaged crank before it cuts out the new rod insert bearings.
The Gray ATV has 11 hours of NON riding run time done at a fast idle with Ceratec in the Mobil oil premixed before filling the crankcase to the full mark.
Our work space is in a very old and holey garage with a Harbor Freight silver tarp for a door. The high today was 8F degrees but we are to see 50F this weekend and should have a new carb kit Wed.
I have since learned there are other brands of additives containing hexagonal boron nitride but this round of testing will be with more or less identical engines both have the same motor oil but only the Gray one with the bad crank due to have been ran without motor oil had Liqui Moly Ceratec added to the Mobil 1 oil
If it starts hammering after the 11 hours of non riding run time we will plan to do the tear down before it fly's apart to see what kind of ceramic coating formed or did not form on the moving parts. We will have to see some mild weather before we do much more other than get both carbs checked out.
We were shooting different parts with an IR temp gun. For the first hour the cylinder temps ran 25F degrees hotter then the last 10 ours of run time. The first hour was a struggle for the engine based on sound and we could hear the RPM increase after the first hour but that is subjective data.
Thanks again for putting me on to Ceratec. Time will tell the tell before we put it in the other 19 engines we have from lawn mowers to diesel tractors and a big block Ford and Chevy engine. By the way the 16 year old son is coming along well and put both back together and correctly torqued all bolts per the Polaris shop manual.