4.6L v8 pre-oiling proceedure

[LMHmedchem]

Hello,

I am getting ready to restart my truck after an extended time sitting. It took forever to get the parts I needed for repair and as a result, the truck has been sitting for quite a while. There was no oil in the pan for a good bit but my understanding is that doesn't really change things for the upper engine where the oil drains out into the pan anyway. I have a new battery so that should not be an issue.

At any rate, I am going to start it up again soon and am thinking that I should implement some pre-oiling procedure or other. I know this is not a case like reinstalling a rebuilt engine, but I still think it makes sense to get some oil pressure going and get some lubricant in there before I try to ignite it. I have read a number of options such as removing the fuse for the fuel pump, removing the connections for the coils, removing the spark plugs, etc. I have no means of evaluating theses suggestions. Is there some procedure that I can give a try that will get some oil into the top of the engine and some pressure into the timing chain setup before I start it up?
(or at least try to)

I am interested to know what everyone thinks about this. Am I overthinking it?

LMHmedchem

 

[Mbrooks420]

I don’t think it’ll make much difference. If you’re spinning the motor the dry metal on metal will still happen. It’ll build pressure faster just running.

 

[J_C]

How long has it been sitting?

Usually if you just hold the gas pedal to the floor while cranking, the fuel injectors don't fire so it will crank away until you let off the pedal, OR till the starter or battery can't take any more.

 

[Mbrooks420]

I wouldn’t try that on a cold engine. lf your throttle cable is stretched like many of them are it won’t cut the injectors and it’ll start and rev out immediately.

 

[sweetbeats]

I wouldn’t try that on a cold engine. lf your throttle cable is stretched like many of them are it won’t cut the injectors and it’ll start and rev out immediately.

Just get a buddy to help verify when the throttle pedal is all the way to the floor the throttle is actually WOT. I would do the FI cut at WOT for startup to crank and build oil pressure. Yeah sure if the oil has drained away its not great, but there’s less impact at cranking RPM than cold idle RPM with firing load on the bottom end and valve train if you just start it right up. If you e been using a good quality synthetic oil it’s quite possible there is still oil coating the internals. This is one of the advantages of using good quality synthetic oil and changing your oil regularly.

 

[Mbrooks420]

The bottom end should be plenty oiled, it’s the top end that’ll be dry. If you aren’t priming it by driving just the oil pump it’s not going to matter. Oil will be everywhere in a second.

To really verify WOT you’d have to check it with a scan tool.

 

[J_C]

Or without a scan tool, have a helper flooring it while you use a multimeter to see if the injectors are getting power pulses, while the fuel pump fuse is out, so you not only know if injectors are activating, you also already got some oil pumped through the engine.

On the other hand, if I didn't detect any slack on the throttle cable, I'd be comfortable enough flooring it. Last time I tried on my '98 last winter, it still hit WOT range.

On the other, other hand... gotta have a scan tool for a vehicle this age! Too much of a PITA to maintain an older vehicle without one.

 

[LMHmedchem]

How long has it been sitting?

This truck has been off the road since the winter when the power steering completely gave out. For allot of that time, I was going out and starting it up once a week and letting it run for 30 minutes. That stopped when I started taking it apart to make the repairs. I had to drain both the oil and coolant for all the repairs I did. I am not sure how long the oil was out of it as there were endless delays getting parts and dealing with the weather. It's hard to work outside here in the winter.

I refilled the oil as soon as I got the oil filter adapter put back on. I would have rather left the filter off for longer to have more room in that area but I didn't want to leave it without oil for any longer than necessary. The engine is now completely reassembled, but I still have not refilled the coolant.

I was looking at this thread,

DIY: Cranking engine to prime oil gallery.

www.planet-9.com

that mentioned a procedure involving removal of the fuel pump fuse. Later in the thread, other posts mentioned the old method for clearing a flooded engine of cranking the starter with the gas pedal to the floor, which has also been mentioned here. At that point, I thought I would check with folks here who have the same truck. I think the other thread was about a Porsche.

To really verify WOT you’d have to check it with a scan tool.

I have and ODBII cable that connects to my computer. I have the software that came with the cable and also Forscan. Will either of these options be able to tell me if I am wide open with the pedal to the floor? Where would I look for that information?

If I can't check this with my computer I will just start it up and see what happens. I will only be running it for a second because I am still in the process of bleeding air from the PS system. That involves a series of quick starts and shutoffs with the vacuum attached to the reservoir. I am also doing a computer reset and a coolant flush, so I have allot of things going on at the same time.

LMHmedchem

 

[Mbrooks420]

This truck has been off the road since the winter when the power steering completely gave out. For allot of that time, I was going out and starting it up once a week and letting it run for 30 minutes. That stopped when I started taking it apart to make the repairs. I had to drain both the oil and coolant for all the repairs I did. I am not sure how long the oil was out of it as there were endless delays getting parts and dealing with the weather. It's hard to work outside here in the winter.

I refilled the oil as soon as I got the oil filter adapter put back on. I would have rather left the filter off for longer to have more room in that area but I didn't want to leave it without oil for any longer than necessary. The engine is now completely reassembled, but I still have not refilled the coolant.

I was looking at this thread,

DIY: Cranking engine to prime oil gallery.

www.planet-9.com

that mentioned a procedure involving removal of the fuel pump fuse. Later in the thread, other posts mentioned the old method for clearing a flooded engine of cranking the starter with the gas pedal to the floor, which has also been mentioned here. At that point, I thought I would check with folks here who have the same truck. I think the other thread was about a Porsche.



I have and ODBII cable that connects to my computer. I have the software that came with the cable and also Forscan. Will either of these options be able to tell me if I am wide open with the pedal to the floor? Where would I look for that information?

If I can't check this with my computer I will just start it up and see what happens. I will only be running it for a second because I am still in the process of bleeding air from the PS system. That involves a series of quick starts and shutoffs with the vacuum attached to the reservoir. I am also doing a computer reset and a coolant flush, so I have allot of things going on at the same time.

LMHmedchem

You should be able to check the live data for the TPS percentage.

 

[Boston Strong]

Hi, I just replaced timing chains, etc. and the oil pump on my '05 4.6. I unplugged the crank sensor and cranked it until the oil gauge showed pressure. EZ, and worked great.

 

[Toby Bear]

Hello,

I am getting ready to restart my truck after an extended time sitting. It took forever to get the parts I needed for repair and as a result, the truck has been sitting for quite a while. There was no oil in the pan for a good bit but my understanding is that doesn't really change things for the upper engine where the oil drains out into the pan anyway. I have a new battery so that should not be an issue.

At any rate, I am going to start it up again soon and am thinking that I should implement some pre-oiling procedure or other. I know this is not a case like reinstalling a rebuilt engine, but I still think it makes sense to get some oil pressure going and get some lubricant in there before I try to ignite it. I have read a number of options such as removing the fuse for the fuel pump, removing the connections for the coils, removing the spark plugs, etc. I have no means of evaluating theses suggestions. Is there some procedure that I can give a try that will get some oil into the top of the engine and some pressure into the timing chain setup before I start it up?
(or at least try to)

I am interested to know what everyone thinks about this. Am I overthinking it?

LMHmedchem

Hi LMHmeedchem

When I revive an engine that was idle for long time, I only bump the starter. I do not crank the engine I just turn it to start than off. After several times I go for a light up of the engine. If your furl system is dry it wont start until there is enough fuel in the lines.

I am sure the only fuel is in the tank and not in the lines. I would not worry about an early fire up. Since you now have air in the lines and not fuel I use this method to start my vehicle.

turn the key to ON
count to 5
key off
count to three
repeat these steps 5 times
then I turn to start.

air compresses as the fuel comes down the line. turning off the pump allows the air to escape, I repeat the process to vent as much air as I can before I attempt to start

GOOD LUCK

 

[J_C]

^ That makes no sense. After the FIRST time you turn the key to on and count to five, press in the fuel rail valve and I bet fuel squirts out because it's made its way to the engine.

This truck has been off the road since the winter when the power steering completely gave out. For allot of that time, I was going out and starting it up once a week and letting it run for 30 minutes. That stopped when I started taking it apart to make the repairs.

Okay I guess I didn't ask a specific enough question. How long since it last ran and pumped oil through the engine?

At this point I'm kinda apathetic about the topic, as there are a half dozen ways to stop an engine from starting while cranked, but even if you don't, it's not catastrophic to just pretend none of this happened and have a tiny bit of wear. It's not a high value classic or sports car.. odds are, something else is going to put it in the grave before that tiny bit of wear ever would.

 

[Toby Bear]

^ That makes no sense. After the FIRST time you turn the key to on and count to five, press in the fuel rail valve and I bet fuel squirts out because it's made its way to the engine.



Okay I guess I didn't ask a specific enough question. How long since it last ran and pumped oil through the engine?

At this point I'm kinda apathetic about the topic, as there are a half dozen ways to stop an engine from starting while cranked, but even if you don't, it's not catastrophic to just pretend none of this happened and have a tiny bit of wear. It's not a high value classic or sports car.. odds are, something else is going to put it in the grave before that tiny bit of wear ever would.

Well, you can try my way. If it starts on the first crank I am wrong....Or......Plus, If you run out of gas and put in a gallon try my way for that too

 

[Mbrooks420]

Well, you can try my way. If it starts on the first crank I am wrong....Or......Plus, If you run out of gas and put in a gallon try my way for that too

No reason to test your way. It won’t work. Sure, it’d work on an even older style car, but with these there will be no ”dry” fuel lines. As soon as you cycle the key fuel will be at the rail.

Way overthinking a non-issue. Just start the damn thing. It’ll be fine. Sitting was probably more damaging than this single start up after a few months.

 

[Sinonsenpai]

I wouldn’t try that on a cold engine. lf your throttle cable is stretched like many of them are it won’t cut the injectors and it’ll start and rev out immediately.

Question about this. Would a stretched throttle cable possibly be a reason why when I put my foot down on my 02 xlt it still seams like it refuses to get up and go? Or should I be looking elsewhere? I also should add that to me the peddle seams harder to push down then what I am use to. But I am only comparing that to a 03 silverado.

 

[Mbrooks420]

It could reduce power slightly. Not sure if the zip tie mod applies to these but I would assume so. The stiffness is probably just a dry/worn throttle cable.

 

[yeet1331]

When I did timing on mine and we needed to lubricate the chains we just unhooked the coils and cranked it so we could lube the new parts up and it worked fine

 

[LMHmedchem]

Well I got it started today. It was pretty uneventful. I was going to check with my computer and see if I was getting WOT or not, but it occurred to me that there was probably no way that this was going to start of the first few cranks anyway. Whether there was fuel at the rail or not, this was probably going to need to crank quite a few times before it lit. I figured that there would be plenty of oil moving before it started up.

This is more or less what I needed anyway because I just wanted to cycle the power steering pump a few times to continue bleeding air. When I reconnected the battery, I did a computer reset by turning the key to the first position and leaving it while all of the locks cycled and such. Then I turned to the second position and there was a bit more of a light show. Finally, I cranked it a few times and then stopped. I turned the wheel a half dozen times all the way each direction and topped off the PS reservoir. I had to do this three times before the fluid level didn't go down any more. Then I started it up. It still took a bit of cranking but it finally lit.

It took a bit for the idle to relearn and for it to settle down. While this was happening, I turned the wheel back and forth again to clear any remaining air. It took a few more times of starting, turning the wheel, stopping, and topping up, before the reservoir held its level. The PS seems to be working well and is very quiet. I left it running for an hour to make sure there were no leaks in the cooling and that no codes showed up.

Everything seems fine and I should have it back on the road soon. I have a bit more suspension work to finish first.

Thanks for all of the opinions and assistance,

LMHmedchem