Hello to everyone. This is my first thread. Probably doing it wrong but got to start somewhere. Replaced spark plugs on my 2010 ranger with the 4.0. I used the Motorcraft SP-412 plugs from Rock Auto. Gap according to owners manual is 0.052-0.056 inch. Drivers side not to bad to change using various length extensions. Passenger side I removed wheel and inner fender. Watch out as there is a vacuum reservoir attached to the inner fender with 2 vacuum lines attached. I left it on but removed the one vacuum hose that was connected to it that goes to the top of the engine to give me a little more slack to reposition the inner fender. The other vacuum line I think goes towards the heater box which had slack so I didn’t mess with it. There is also an electrical wire attached beside the reservoir which was also disconnected to avoid putting strain on it. Truck has 80,000 kms. First time they have been replaced. Manual says to do at 96,000 kms. Truck was running fine but it was time. Existing plugs looked fine but gap was excessive due to age. Roger

 

Welcome to the forum

Good work

Nice detailed descriptions

The vacuum reservoir stores vacuum for the cabs Vent "motors" which are vacuum activated, Panel, Floor, Defrost
Defrost is the default(no vacuum) setting
So if you ever have an issue with vents then that black line that runs to firewall or the reservoir is the problem, the black line can melt or get brittle and crack from exhaust heat

 

Thanks for the info. You’re right those lines seem pretty close to the exhaust manifold. I’m surprised they haven’t melted yet. I did have a look at them and they are in pretty good shape though. Good to know if there’s a problem where to start looking. Roger

 

Thanks for the info. I had no idea there was a "vacuum reservoir". I must eyeball mine.

These lines being near the exhaust manifold might be THE BEST candidate for silicone replacement?
Plus you can get 'em in pretty blue or red.

 

Yes, the hard plastic vacuum lines are much cheaper to have made by the thousands, if not millions, but they are prone to cracking as they age, as we all are, lol

Vacuum reservoir keeps the Vents in the cab in the driver's selected setting when you are accelerating, vacuum drops to 0 in the intake at that time, you can tell if there is a vacuum leak in this system if air starts blowing out Defrost vent when accelerating then returns to panel or floor after you are up to speed(vacuum returns to intake manifold)

Power brake booster is also a vacuum reservoir, for the same reason, so you have power assist in case engine should stall while driving, no more vacuum, you should have 3 pumps of the brake pedal before vacuum is gone, you can test for that after shutting engine off

Yes, you can splice or replace these lines with any other type of vacuum hose of correct size, no clamps are needed if fitting is snug, these have negative pressure inside so PULL together, vs say a heater hose which has positive pressure so tries to PUSH apart and needs a clamp to prevent that

 

I had another look at the vacuum lines. They are close to the exhaust but seem stiff enough not to be pushed closer to the exhaust manifold or forced by higher speed creating more wind velocity in the engine compartment. I think the plastic breaking down would happen first. As Georgeandkira stated some high temp silicon hose may provide a long lasting repair. Today I plan to service the trannny. I will post my experience. Roger

 

If you dont have a smoke machine youtube how to make one so you can check for vacuum leaks in your truck. Wish I had made mine years ago. I have found leaks even on new parts!

 

On topic: My vacuum reservoir is sphere shaped, smaller and more forward than I expected reading this post.
The line extending rearward is the hard plastic type and flops around. Heater doors are working fine.
Were there securing clips? I'll look for myself but if anyone knows, I'd appreciate it.

 

No, no clips as far as I have seen on later model Rangers, you can add them

On my 1994 Ranger the vacuum reservoir is small, sits on top of heater box

Drawing here: https://i899.photobucket.com/albums/.../Reservoir.jpg

Super easy access