Nordicflame

iTrader: (4)

Just a couple of thoughts. Don't know if they're right or not but one would be;
I would think the heads would get more water with the thermostat in and partially closed. This would force water to the head passages rather than just a free escape path out the the thermo housing. Wouldn't it help also move air pockets out. Yes/No???
The other is I would think you need adequate temp to seat the rings properly.

Rookie

iTrader: (4)

http://www.mototuneusa.com/break_in_secrets.htm

This is the philosophy I have always used in my cars, snowmobiles and motorcycles. I do not know if it has been the right way, but it has worked. I have not had a failure due to it.

racinbird

Also I have heard that with a new cam you only want to run the lighter spring for less tension the first break in then swap in the other spring or two once you actually drive it. Maybe this is only relavent on non-roller cams? just my .02

PatriYacht

I have heard this with Nascar engines because they use solid flat tappet cams with a lot of spring pressure. The breakin for these cams is critical. With almost any cam used in a boat, this would be unnecessary.

Crazyhorse

The engines we've been doing around here, like Dyno's, mine, SuperV's, Waterfoul's, only have about 110 pounds on the seat so the spring change isn't necessary. But the cams still need to be broken in properly. That's why we run them on the floor before they go in the boat. Check for oil and coolant leaks, pressures and temperatures, and set the ignition timing. After the break-in run the oil and filter is changed, it's run again, and antifreeze is run through it if it's cold enough to freeze. Spark plugs are removed to get a small amount of oil into the cylinders, turn the engine over by hand, and reinstall the plugs. Then all the openings are taped shut and it's ready to go in the boat.

220BR

Rookie, interesting post. Makes some sense and I sure like it better than the conventional break-in.
Problem for me is I always have to break in (at least the cam) on the trailer.

Reed Jensen

Only a small amount of the oil is "filtered" as the oil flows through the engine and filter... all " full flow" filters... ALL FILTERS.. and engines have an oil bypass because you can't push thick cold oil through a filter matrix that has holes only microns big. If there isn't a bypass for the filter the oil will just exit out the pressure relief valve in the pump.The oil has to bypass most of the time... the filter only flows all the oil at low rpm's and when the oil is very hot... like at idle after the engine is totally warmed up. If there isn't a bypass system for the filter the bearings will be starved for lubrication and will fail quickly... trust me on this one guys... If you remove the built in oil filter bypass on a chev engine... you have to run a filter that has a built in bypass like a fram HP6. Or suffer bearing loss..

Crazyhorse

Yeah, whatever you say, bucko.

blue thunder

I've blocked my bypasses and will run this summer with none. I am going to run filters with bypass valves. Problem with a boat engine and the bypass in when it opens, the oil not only bypasses the filter, it bypasses the cooler. Therefore, you always have X amount of uncooled, unfiltered oil running through the system. Blocking the bypass, oil will only bypass the filter (via filter bp) and will be forced though the cooler. This way you will run a percentage of unfiltered oil but all oil will alway be cooled. Hope it works!!

BT

Crazyhorse

It will work fine, BT.