Let's assume the Cummins 8.3L diesel hasn't been started for a month.When I turn it over - is it dry metal on dry metal on the main bearings and crank? Or is it possible that the main bearings are sitting in an oil bath of some sort. There are a couple of seconds between the engine firing and the oil pressure coming up. I assume that the bearings feel oil pressure before the pressure sensor does and then the signal has to travel 36 feet to the gauge. I have felt how smooth crankshafts are where they come in contact with the main bearings and I know these main bearings are relatively soft. Having said that - does your engine die a little every time it sits for a month between starts? Are there other contact points like rod bearings that suffer as much or more than the main bearings? Thanks in advance for your insights!

DonBaja wrote:Let's assume the Cummins 8.3L diesel hasn't been started for a month.When I turn it over - is it dry metal on dry metal on the main bearings and crank? Or is it possible that the main bearings are sitting in an oil bath of some sort. There are a couple of seconds between the engine firing and the oil pressure coming up. I assume that the bearings feel oil pressure before the pressure sensor does and then the signal has to travel 36 feet to the gauge. I have felt how smooth crankshafts are where they come in contact with the main bearings and I know these main bearings are relatively soft. Having said that - does your engine die a little every time it sits for a month between starts? Are there other contact points like rod bearings that suffer as much or more than the main bearings? Thanks in advance for your insights!short simple answer.NO and u don't need to start the motor every monthIf you do u must get it up to full operating temperature for XX minutes

Let's assume you haven't started it since yesterday.Engines die a little every time you start them....no pre-oilers but oil is pretty darn good at coating parts and leaving a bit of residue.If you do decide to start it........take it for a spin. That's better for it then just starting it.

Yes it dies every time you start it so another reason to not start it every month. Good news... it has thousand of lives as there's a little oil still in there.

Let me rephrase. Per Cummins (as well as Caterpillar, etc) if you start it, drive it at least 25 highway miles-- enough to get the OIL, not just coolant up to operating temperature. It is moisture in the crankcase that you want to avoid, and you can not get the oil up to operating temperature except by driving at highway speeds/under load.

You really don't need to worry about the "dry start" scenario. It just isn't an issue.

Help Me to Understand Dry Start ? | Good Sam Community

garry1p
Explorer
Mar 09, 2014
Farm equipment lasts for many many years and they do not have a pre lube set all winter and fire it up in the spring.
hammer21661
Explorer
Mar 09, 2014
we start boat motors that have sat for years then put them to work.No problems from "dry start".All of them set for 6 months a year.
azrving
Explorer
Mar 08, 2014
wa8yxm wrote:
This does not address the O/P's question but I have a thought......

Why can they not put an "oil Priming Pump" on the engine, a small electric you run for like 30-60 sedonds to "Prime" the oil system and get oil up to the top rail?

I guess the engine makers do not feel it is needed.

Years ago I remember seeing pre lube systems. It uses an accumulator to hold oil and when electrically activated the accumulator pushes the oil charge into the oil system. This one example and it comes in pre and post shut down.
http://engineprelube.com/
jeffo
Explorer
Mar 08, 2014
Anyone running MotorKote friction fighter? Heard the adds. But does it really work?
wa8yxm
Explorer III
Mar 08, 2014
This does not address the O/P's question but I have a thought......

Why can they not put an "oil Priming Pump" on the engine, a small electric you run for like 30-60 sedonds to "Prime" the oil system and get oil up to the top rail?

I guess the engine makers do not feel it is needed.
ScottG
Nomad
Mar 08, 2014
You really don't need to worry about the "dry start" scenario. It just isn't an issue.
wolfe10
Explorer
Mar 08, 2014
Let me rephrase. Per Cummins (as well as Caterpillar, etc) if you start it, drive it at least 25 highway miles-- enough to get the OIL, not just coolant up to operating temperature. It is moisture in the crankcase that you want to avoid, and you can not get the oil up to operating temperature except by driving at highway speeds/under load.
Ivylog
Explorer III
Mar 08, 2014
Yes it dies every time you start it so another reason to not start it every month. Good news... it has thousand of lives as there's a little oil still in there.
Old-Biscuit
Explorer III
Mar 08, 2014
Let's assume you haven't started it since yesterday.

Engines die a little every time you start them....no pre-oilers but oil is pretty darn good at coating parts and leaving a bit of residue.

If you do decide to start it........take it for a spin. That's better for it then just starting it.
davebrown
Explorer
Mar 08, 2014
DonBaja wrote:
Let's assume the Cummins 8.3L diesel hasn't been started for a month.

When I turn it over - is it dry metal on dry metal on the main bearings and crank? Or is it possible that the main bearings are sitting in an oil bath of some sort. There are a couple of seconds between the engine firing and the oil pressure coming up. I assume that the bearings feel oil pressure before the pressure sensor does and then the signal has to travel 36 feet to the gauge. I have felt how smooth crankshafts are where they come in contact with the main bearings and I know these main bearings are relatively soft. Having said that - does your engine die a little every time it sits for a month between starts? Are there other contact points like rod bearings that suffer as much or more than the main bearings? Thanks in advance for your insights!

short simple answer.NO and u don't need to start the motor every month
If you do u must get it up to full operating temperature for XX minutes

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Help Me to Understand Dry Start ?

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