Fogging My Perkins ??

[cburger]

Have a Perkins 4-108 that I want to lay up for the winter. The question is this: The Perkins manual calls for spraying in each cylinder with 1/8th of a pint of lubricating oil, there are also fogging products on the market already in an aeresol form, what would the best way to go?

[Vasco]

Most of us don't bother with lubricating the cylinders when laying up the engine for winter. Just run anti freeze through the raw water side, loosen the belts a bit and that's it. Some remove the impeller. When starting in the spring hold the stop out and crank a few times before firing.

[cburger]

Engine is out of the boat, oil has been drained. The reason for fogging as I understand it is because Sulphuric Acid is a by product created as a result of the lubrication process and when the motor sits unused for long periods of time corrosion of the cylinder walls can take place?

[Vasco]

In that case just pour lube oil into each cylinder and hand crank with the decompression lever up. Didn't realize you had the engine out, though you were just laying it up for the winter. Removing the engine in those circumstances is a bit drastic.

[maxingout]

I was advised to disconnect the hose joining the exhaust elbow to the aqualift muffler when we laid up. The rationale behind this maneuver was that the moisture in the muffler would expose the exhaust valves to higher levels of humidity during the period of storage if the hose was still connected.

I don't know if this is true of false. It seems reasonable to me, but it may be totally bogus.

[delmarrey]

Most factory made wetlifts have a drain plug installed at it's base. If not, then I would install one.

[never monday]

Foggin oil could be used, BUT it's best applied with the engine running. I'd pull the injectors and spray WD40 in there.

[Alan Wheeler]

As Pat said.
Plus....The actuall issue should not be one that is found over just a winter. The problem accurs over a far longer period, something more like two years. The problem is that the oil on the cylinder walls eventuall disappears completely. You then have an aluminium piston, steel alloy piston rings and yet another type of steel cylinder liner. Add a little moisture and perhaps some acid residue(it doesn't take much) and add some time, and you get the whole shebang corroding. Worst case scenario is that the cylinder wall can get etched and pitted where the rings are in contact. Often the result is a slightly siezed motor, although it is usually easy to unstick them and make them rotate again. It is the possible etching damage that can occur that is the biggest concern. So etc oil of any type down the bore is helpful, along with the intake being plugged by a rag to keep air flow and thus moisture out. A dessicant bag down the intake is very helpful as well. The idea of engine makers suggesting a specific oil, is because it burns easily and helps with restarting at the end of layup. Unlike lubricating oil that does not aid restart and will blow lots of blue smoke till it burns away.

[cburger]

Thanks All

[hellosailor]

IIRC one of the major purposes of fogging the engine is to swamp the piston rings with the fogging oil, so that condensation in the cylinders will not rust them over the winter. The condensation will run "downhill" off the piston head to the cylinder walls (and the rings) and in Nyack, there will be regular thermal cycling in the winter to form condensation in the engine.

Two ounces of oil in each cylinder seems like a typical British solution [g] just drown them to ensure it doesn't all leak out past loose rings in all those months. And WD-40 (which is mainly kerosense IIRC) seems easy but not great protection compared to other things.

As long as it is oil, preferably thick rather than thin oil, I think any product would do a decent job of keeping the internal surfaces coated and preventing rust on them.