Log in

View Full Version : Prelubing a dormant 4.6 motor...........



PHHHHTT
02-04-2012, 10:17 PM
I used the "Search" feature in the forums and it did not find a match for the subject, so I will place this issue before the members.

Do any of you have a preferred method to prelubing a 4.6 that has been sitting for a considerable amount of time before actually starting the engine?

I have dealt with many Ford engines but this is the first time I cannot prelube an engine because the oil pump is driven by the crankshaft rather than the distributor.

I would like to pressurize the oiling system and rotate the engine by hand while doing so to be certain all moving parts have been lubed before actually starting the engine. You know how the engine start-up flare will immediately send the engine above 1500 rpms before settling down. I'm concerned about what damage can occur during this time. It has been quite awhile (18+ months - I know the fuel system will need attention as well) since I last ran the car and I am finally where I can devote time to make necessary repairs.

The car has run Mobil 1 synthetic 5w20 oil most of it's life (I switched to 5w30 Mobil 1 on the last oil change). I am thinking I should put in a very light weight oil (0w20 maybe?) to perform the prelube, install a pre-filled new filter (at least as much as possible), prelube engine by whatever means are suggested, start the car and let it achieve operating temperature. Once this is done, shut down the engine, change the oil back to 5w30 Mobil w/pre-filled new filter as normal, start car and then proceed with the other issues.

One suggestion I have found on a Mustang forum is to pull the plugs (which will remove compression forces off the crank bearings), disable the ignition, and use a remote starter to spin the engine until the oil pressure is reached. This method would not lubricate anything before being subjected to motion but I think would be better than just changing the oil and firing it up.

I have also read where a starter cannot spin an engine fast enough to achieve sufficient oil pressure, it may produce enough to trip the oil pressure switch but that's about it (this info was written in general application to most engines, may not apply to a modular engine).

I know I could just change the oil and start it up. That is probably the most direct and easiest way to deal with the issue, but I'm not concerned about ease of the job. I want to protect the engine from a dry start condition.

Thanks for any suggestions you may offer.

Randall

RacerX
02-04-2012, 10:35 PM
Pull the fuel pump fuse and turn it over for a few seconds. There is no oil pump switch. The pump is mechanical and attached to the crank. As the crank rotates, the rotor inside the pump creates suction pulling the oil through the system quickly. I think there was a way to put oil into the system where the pressure sender is, but, I don't think you need to go that far.

Thomas C Potter
02-04-2012, 11:26 PM
I agree that you should do something more than turn the engine over. One option is to install a oil cooler adaptor block ($60) in between the filter and engine, then use an external pump to push syn oil. I remember reading that some guy uses an agicultural pump, about $150. All my cars have an electric preluber ($350) that I use before starting. Once you have this block installed, you may ponder an elctric preluber full time, or a mechanical preluber tank. If you do remove plugs, make sure the entire holes is very clean of course. Good luck.

03sport007
02-05-2012, 12:17 AM
It takes balls of steel but if you hold the throttle to the floor I'm not sure what it does but it won't start. I read it somewhere and it works on my car. If I go a week or so with driving I hold the go peddle to the floor crank it over for about 15sec and let the oil pressure build. Release the key, take my foot of the floor, turn the key and it starts right up.

EMAS
02-05-2012, 02:21 AM
Holding the throttle past at WOT engages the flood clear mode and prevents the injectors from firing.

Do not change the oil first as that will cause air pockets in the system. I'd just pull the plugs, maybe put a few drops of Marvel Mystery Oil in each cyl, pull the fuel pump fuse or relay and crank until you get pressure and do that a couple of times. With a good battery the engine will spin fast enough to build up to or near full pressure. I've done it on a number of vehicles of different makes and models with a professional oil pressure gauge and have seen it personally.

The other option is a pressure pot style pre-luber that goes in the oil pressure sender port, fill it with oil, pressurize it with compressed air and inject it into the system.

massacre
02-05-2012, 07:40 AM
You can use a garden sprayer with an adaptor that attaches to the port of the oil pressure sender on the oil filter adaptor. This will pump up the hydraulic lash adjusters, which have likely bled down to some extent.

RF Overlord
02-05-2012, 08:10 AM
I am thinking I should put in a very light weight oil (0w20 maybe?) to perform the prelube,Unless this motor will be at very low temperature (think Ice Road Truckers) when you go to start it, any oil will be way thicker than at normal operating temps, so using 0W-20 will not be of any benefit. I agree with EMAS...don't bother changing it first.

TFB
02-05-2012, 09:42 AM
It takes balls of steel but if you hold the throttle to the floor I'm not sure what it does but it won't start. I read it somewhere and it works on my car. If I go a week or so with driving I hold the go peddle to the floor crank it over for about 15sec and let the oil pressure build. Release the key, take my foot of the floor, turn the key and it starts right up.

This is what I'd do...

Change the oil after it runs awhile and is up to full temp... If you change it first it will take longer to build pressure(more cranking time), and basically you've wasted oil since you plan on dumping it in a short while...

PHHHHTT
02-05-2012, 11:46 AM
Many thanks to all who responded to my issue. There were items pointed out that I had not considered or were aware of.

I like the idea of an engine prelube system. This would solve my current quandry and extend the life of the engine. I'm not up to speed on the pros and cons of either prelube systems (electric pump or accumulator). Thomas, do you have any further info as to your preference and which manufacturer you recommend?

One item not brought up is the contamination of the current oil due to condensation and other possible time related issues. This oil/engine has not been exposed to any unusual circumstances that would warrant an immediate oil change, it has just been in there a long time. I am of the mind set that an oil change is necessary for this reason alone. But maybe in this instance, if I can't/don't prelube the engine, would the lack of fresh oil time frame be worse for the engine than circulating the current age-comtaminated oil that will minimize the lack of oil time frame?
(Boy, I had to think about how to phrase that)


Thanks again for all of your responses.
Randall

justbob
02-05-2012, 12:34 PM
Personally I would just start the car and take it for an oil change.

EMAS
02-05-2012, 01:25 PM
It is my opinion that changing the oil before you start it would be worse than starting it with the oil that is in it now. I don't have any scientific facts one way or another however. I would change it as soon as you've got it up to temp though.

-Matt-
02-05-2012, 02:19 PM
Personally I would just start the car and take it for an oil change.


This....

Trust us... there is a car that was driving around with holes in 4 of its cylinders for 15 months... nothing you could really do would cause any damage. Pull the fuel pump fuse or hold WOT and crank for a while, then start it. Don't read so much into it.

TFB
02-05-2012, 05:40 PM
Oil that has light to moderate mileage isn't going bad by setting.. As long as the oil cap, and PCV plumbing is in place, there is basically no way for moisture to enter the crankcase... If it had high mileage prior, then the oil should have been changed before storing...

PHHHHTT
02-05-2012, 09:25 PM
Just want to acknowledge and say "Thanks" to those who responded the second time.

FWIW: the responses will help bring Trilogy #237 to life.

Randall

MyBlackBeasts
02-05-2012, 09:58 PM
I agree that you should do something more than turn the engine over. One option is to install a oil cooler adaptor block ($60) in between the filter and engine, then use an external pump to push syn oil. I remember reading that some guy uses an agicultural pump, about $150. All my cars have an electric preluber ($350) that I use before starting. Once you have this block installed, you may ponder an elctric preluber full time, or a mechanical preluber tank. If you do remove plugs, make sure the entire holes is very clean of course. Good luck.

What are you using for a pre-luber? I have working with a hydraulic pump engineer on a system for my vehicles.

Thomas C Potter
02-09-2012, 04:30 PM
PHT, I use an electric preluber. Nice to hear the little motor bogg down once pressure is max. The compnay is out of (philly??) PA. Email me if you want to dig up info, tpotter@usps.gov.