spark plugs change - any tips?

[AJay]

Hi All,

I have a 1999 Forester 2.5 L automatic 62,000 miles. I've decided to
change the plugs myself. Is this a major undertaking? I heard that I
might have to remove the battery and washer fluid container to get at
the plugs on the left side. Is this true?

Thanks for any assistance.

A.J.

 

[MN]

Hi All,

I have a 1999 Forester 2.5 L automatic 62,000 miles. I've decided to
change the plugs myself. Is this a major undertaking? I heard that I
might have to remove the battery and washer fluid container to get at
the plugs on the left side. Is this true?

Thanks for any assistance.

A.J.

Google the group.

There have been articles about this topic.

Access is difficult. I use a piece of plastic tubing (Home Depot
lawn section) about 10 inches long as an extension when mounting
the new plugs.

First, I delicately, but securely, insert the ceramic end of a new spark
plug into the tubing. The plug fastened in the tubing, then I proceed to
insert the plug into the deep cavity in the engine- where the spark
plug holes are located.

I manipulate until I find proper fit into the threads, then screw it as
much as possible turning the plastic tubing, then I pull at the tubing
until it separates from the plug (if you insert the plug into the tubing
to tigh youre going to have pull hard!). Only then I proceed to tighten
with a wrench.

Be careful, visibility is almost non existent, using a small mirror
helps a bit. The job is very easy when using the tubing but can
be a bit intimidating nonetheless ( I am not a mechanic!).

MN

 

[Edward Hayes]

On my 2000 Forester I needed to remove the window washer bottle and
the air intake plumbing up to the filter housing (10 & 12mm sockets).
Twist and pull very hard to remove high voltage cables from each plug
(grab only the boot end & not the wire). I use a 3/8 inch ratchet (8
inch) and a FLEXHEAD spark plug socket with a rubber insert and a 3 or
4 inch extension. If you purchase NGK plugs for your Forester they
come pregapped to spec. of 0.044" but I check the gap anyway with a
wire gage. I coat the outside of the spark plug rubber boot with
dielectric grease (very thin coat). I use a very small amount of
antsieze compound on the spark plug threads. Recommended torque is 15
ft/lbs +/- 2 ft/lbs which is just snug AFTER you feel the crush gasket
collapse. Expect ~ 1.5 hours the first time and 25 minutes each
succeeding plug change. Cheers. Ed Hayes

 

[Rick Courtright]

wire gage. I coat the outside of the spark plug rubber boot with
dielectric grease (very thin coat). I use a very small amount of

Hi, Ed

Just checking, did you really mean the OUTSIDE of the boot? Maybe I've
been doing it wrong: I put a little on the actual metal end of the plug
where the wire connects, then a tiny bit more INSIDE the boot to help
keep it from sticking to the ceramic. But I'm also left-handed and
dyslexic...

Rick

 

[Edward Hayes]

I just do the outside of the boot where it slips into the metal tube.
Maybe it would be good to coat lightly the connector too.

 

[AJay]

Thanks for all of the tips. I appreciate it.

A.J.

 

[JohnO]

Hi, Ed

Just checking, did you really mean the OUTSIDE of the boot? Maybe I've
been doing it wrong: I put a little on the actual metal end of the plug
where the wire connects, then a tiny bit more INSIDE the boot to help
keep it from sticking to the ceramic. But I'm also left-handed and
dyslexic...

Speaking as an electronics guy...dielectric grease is non-conductive.
At first glance it would seem a bad idea to coat the conductive metal
parts with non-conductive material. Obviously it still works or you'd
be writing something different, but I can't help but think that it
increases the resistance of the connection.

-John O

 

[Rick Courtright]

parts with non-conductive material. Obviously it still works or you'd
be writing something different, but I can't help but think that it
increases the resistance of the connection.

Hi,

I never checked the conductivity thing--I was always taught dielectric
grease is used to help prevent corrosion and "stickosis." Considering
the high voltage and low current involved w/ plug wires, I doubt it's
much of an issue. OTOH, Subaru once issued a TSB or other directive
suggesting its use for the various sensor connections which carry both
low voltage and current (they were having corrosion problems) and I've
used it for them w/o problems.

One place I've heard NOT to use it is your O2 sensor connections: I've
read some O2 sensors use some kind of hollow insulation for heat
dissipation, and grease will block whatever tiny little bit of air flow
that exists, creating "bad" readings from the sensor.

Rick