Prelubricating Cylinders With Heads On

[Fitz98]

I am in the reassembly stage of an extended project on my 98 Expedition 5.4.
I tapped in new Cal-Van inserts into the heads to repair spark plug threads and prevent failure in the future.
Part of this process had me blowing out the shavings from the cylinders through the spark plug holes and cleaning the threads with brake cleaner (which in turn entered the cylinder) before installing the new inserts. On top of that, this process mixed in with my job has had my truck down for several weeks. I work on it when I can.
At this point the cylinder walls and rings are going to be bone dry and the procedure was done with pistons at bottom of stroke with valves closed.
Anyone have any ideas how I can pre-lube the cylinder walls and pistons through the spark plug holes before sticking in the new plugs so the cylinders and rings won't be completely dry on initial startup? Something that won't foul up the new plugs or cat converters.
Also have access to intake valves since the intake manifold is still off, but seems like the spark plug hole would be the more suitable access point to work through.

 

[P10crew]

MMO fogger

 

[Chris142]

A little tcw3 oil in there won't hurt.

 

[gathermewool]

Depress your gas pedal fully and crank. After several second, release the gas pedal and let the engine start normally.

More importantly, how did you say you got the shavings out of the cylinders?

 

[Fitz98]

I simplified the description of getting shavings out. I used a combination of techniques. Initially inspected with bore scope, then first vacuum with shop vac and clear , flexible tube, then follow up with a blow out with compressed air and air gun with blow tip, re-inspect with borescope. 2nd blow out with compressed air. After confirming shavings are all out with bore scope inspection, I used brake cleaner into spark plug hole to clean threads, then blow out again with compressed air. Repeated as needed until tapping oil is removed from threads and all shavings are out of cylinder.

 

[andyd]

wont aluminum shavings burn in the cylinder?

 

[Fitz98]

I asked myself that same question and ultimately decided it was not worth the chance when I could just get them out rather easily.
I also thought that there may be a potential for the shaving(s) to melt rather than burn and fuse to a valve or ring even if temporarily, or maybe get pushed out the exhaust valve and melt in the cat converter.
I don't really know, just theorizing, but the thought crossed my mind that aluminum is softer that steel so shouldn't scratch the piston or cylinder wall, and has a melting point that I would imagine is lower than what the combustion temperature is in the cylinder.

 

[Chris142]

Originally Posted by andyd
wont aluminum shavings burn in the cylinder?

No but being softer than the rings and cylinder walls they won't hurt anything on their way out.

 

[rubberchicken]

Your best bet is to get engine fogging oil. This is used heavily in the marine world while winterizing engines. These are just examples- and you want the type with just the standard red tube: the clear tube with threaded fitting is only for specific OMC engines.

https://www.amazon.com/s?k=engine+fogging+spray&ref=nb_sb_noss_1

Now- one word of caution- make sure the red tube is secured for every spray- I have been winterizing engines for 30 years, and ONE year I accidentally let the tube get forced all the way into the cylinder. It took days to get it out.

 

[talest]

If your goal is to lubricate the cylinder walls.. a capful of oil in each cylinder and turning it with the starter with the gas pedal full depressed (so that no additional fuel goes in there) should lube it up. You may need a funnel if doing this on a 5.4.

Might even be able to do this by hand..

 

[demarpaint]

There are several ways to do it. I have used fogging oil and sprayed it in. MMO via, a syringe with a hose on it, oil via a syringe with a hose on it.

 

[Linctex]

2-cycle oil with a small syringe

 

[WyrTwister]

First thing , with the fuel pump not pumping , crank it a few turns with the speak plugs out . This may or may not blow any more debris out the spark plug holes .

For what it may or may not be worth , I have seen videos of engine builders using WD-40 , engine oil , assembly lube and probably other things on the rings & pistons . When they are installed in the cylinder bores . Who knows what is best ?

Did the plugs blow out or break off ?

Best of luck to you ! :-0

 

[Cujet]

I'd be concerned any oil will trap particulates that would otherwise blow out the exhaust. I'd start it dry.

 

[Linctex]

Originally Posted by Cujet
I'd be concerned any oil will trap particulates that would otherwise blow out the exhaust. I'd start it dry.


I wouldn't be concerned at all.

Sounds good "in theory" but it has never been an issue "in practice"