ENGINE PRE-OILING PROCEDURE

[TANTO]

Just did my valve cover gaskets and noticed that my camshaft lobes were totally DRY after about 7 months! Arrg, I assumed that modern day mobil one 10-30 would leave a little bit on the lobes – not so. As we know a very large part of engine wear occurs at start up. Crank/rod bearings and cams take a beating while waiting for the oil pump system to get oil to all surfaces. There is a lag between when you start you the engine and when oil gets to all critical surfaces. What do we know about pre –startup circulating oil for the NSX?. I assume a fuse should be pulled for ignition and fuel? Different engines take different crank times to get oil to the heads. In the old days we would have the valve covers off, spin the oil pump with a drill and actually see when the oil came to the heads, but I assume that in our situation we can only guess on a good cranking time in seconds. I do let my car set for up to a year at a time and feel the need to pre-lube after an extended winter. To repeat, what fuses to pull and how long to run dry to get oil to camshafts? From my experience some engines oil almost instantly and some take a good 45 seconds. Any thoughts on our motors greatly appreciated. I'm using mobil 1 10-30 fwiw. TIA

 

[Honcho]

Just did my valve cover gaskets and noticed that my camshaft lobes were totally DRY after about 7 months! Arrg, I assumed that modern day mobil one 10-30 would leave a little bit on the lobes – not so. As we know a very large part of engine wear occurs at start up. Crank/rod bearings and cams take a beating while waiting for the oil pump system to get oil to all surfaces. There is a lag between when you start you the engine and when oil gets to all critical surfaces. What do we know about pre –startup circulating oil for the NSX?. I assume a fuse should be pulled for ignition and fuel? Different engines take different crank times to get oil to the heads. In the old days we would have the valve covers off, spin the oil pump with a drill and actually see when the oil came to the heads, but I assume that in our situation we can only guess on a good cranking time in seconds. I do let my car set for up to a year at a time and feel the need to pre-lube after an extended winter. To repeat, what fuses to pull and how long to run dry to get oil to camshafts? From my experience some engines oil almost instantly and some take a good 45 seconds. Any thoughts on our motors greatly appreciated. I'm using mobil 1 10-30 fwiw. TIA

Been there done that too!

The NSX will circulate oil fairly quickly due to the excellent and tight tolerances in the system. You get good pressure almost instantly. Obviously, the best method is to use an assembly lube on the parts. I prefer Melling Mell-Lube for the camshaft assembly because it has a very strong ZDDP-based additive that provides lubrication even if the oil carrier drains away. My engine was SILENT on restart after almost 5 years of sitting dry.



If you can't use assembly lube (I think you said your valve covers are already installed, you'll probably still be ok. The NSX gets oil for the camshafts and rockers off of the No. 4 main, so it does take a second for the oil to make it across the bottom control plate, through main 4 and then up through the oil control ports into the heads. After a few crank rotations, oil will be in the rocker shafts. The camshafts are hard nitride coated and the rocker arms are tempered hardened steel, so any wear is going to be negligible. Where you need to be worried is the camshaft races, which are aluminum. But, if you've got the correct amount of oil in the pan, it won't matter. 10 engine rotations, for example, is not enough for the cams to grind the aluminum races out of spec. You would have to run the engine dry for a minute to cause that kind of damage.

The basic "dry" startup method is as follows:

1. Pull the plug out of the ignition module on the top of the intake manifold. This disables spark.
2. Pull the plug out of the fuel injector resistor ballast next to the engine bay fan. This disables fuel.
3. Crank the engine for two or three 5-second blasts. This helps prime the oil system.
4. Crank the engine for 30 seconds. You should see the oil pressure gauge needle move. This means your cams are coated with oil and it is safe to run the engine.
5. Plug everything back in and fire her up!

Hope this helps.

 

[Optical]

Also remove the spark plugs so there is less load on the rotational parts