Spark Plug Cramps

[usaru]

Getting set to do the first cramped up SP change on the boxer engine. Found different opinions in previous threads about whether the engine should be warm or cold when taking plugs out/putting them in. Anybody with a definitive answer? Ta.

 

Cold/hot, 30% less torque with anti-sieze, it could be easy to put them in and end up too loose or too tight.

 

Anybody with a good tip for this job they'd like to share?

[idosubaru]

i don't think there's a definitive answer because not every plug removal is the same. some catch, some do not. if every single one stripped when removed in a certain fashion, then yes a "definitive" way may arise, but that is not the case. i do them cold all the time without issue, try that way first. if you notice a plug getting stiffer and catching, then you may want to tighten it back down and warm the engine up to see if that helps. if that happens, chasing the threads with a hole chaser is a good idea, to keep your piece of mind.

 

definitely use antiseize on the ones you install.

 

NGK plugs, Subaru OEM wires only if this is for your 99 EJ25. that's a fun one to do spark plugs on (J/K).

[Skip]

"Anybody with a good tip for this job they'd like to share?"

 

1) Pull the front wheels

I believe you will see access holes for the ratchet extensions

there.

 

2) Be very careful removing the boots, twist and pull.

 

Hope this helps.

[srs_49]

Don't know how much room you have in the engine compartment, but it was a real bear doing the plugs in our '02 OBW H6. I used every adapter, extension, spark plug socket, flex joint, etc in my collection to get the job done.

[Rooster2]

I did the spark plug and wire replacement on my 99 OBW last Spring. I bought the car used with about 150K on the odo. It didn't take me long to figure out that the car had the original plugs and wires on the motor. I had a devil of a time getting the wires to pull off the ends of the spark plugs. I actually had to rip the wires off using long handled channel locks. The turn and twist method of removal was out of the question.

 

To remove the plugs, you will need to remove the battery and wind shield washer fluid reservoir on one side of the engine, and the air intake plumbing on the other side of the motor. This is necessary to gain access to the plugs. Have available every size small drive extension that fits on the end of a 3/8" drive handle. Different length spark plug sockets are helpful too. You will be doing a lot of finger untightening of the plugs, once you have "broken loose" a tight plug. Again do finger hand tightening of the new plugs. This prevents cross threading of the plugs into the soft aluminum head.

 

You will be amazed how much time you spend installing just 4 spark plugs. It is just tedious work that makes you want to cuss a lot during the process. Thankfully plug replacement is not something that needs to be done often. Of all the work to be done on a Subie motor, changing plugs is one of the worst.

Doing other motor work on a Subie is a piece of cake. Good luck and have patience.

[wtdash]

RE: replacement:

On my '97 there was a Subaru spark plug tool (in the rear w/the tire stuff). I wasn't smart enough to remember it when I did mine, so can't tell you how well it would work.

 

Also, people suggest using a piece of hose/tubing over the end of the plug to help fish 'em out/in.

 

Good luck

[usaru]

"You will be amazed how much time you spend installing just 4 spark plugs."

 

Given that, does the job have to completed all at once? Would it be wrong to do one or two (with new wires) at a time and drive around for a couple of days before doing the otherS?

[ericem]

It would sort of be wrong because one side will be working more efficiently then the other most likely.

[OB99W]

[...]Would it be wrong to do one or two (with new wires) at a time and drive around for a couple of days before doing the otherS?

Only if you think the remaining cylinders would be likely to go on strike, protesting preferential treatment of the others.

[Rooster2]

"You will be amazed how much time you spend installing just 4 spark plugs."

 

Given that, does the job have to completed all at once? Would it be wrong to do one or two (with new wires) at a time and drive around for a couple of days before doing the otherS?

 

 

That is exactly what I did. I installed two plugs one night, then two plugs the following night. Suggest as others have....use antisieze on the threads of the new plugs going into the car. It helps lube the threads during installation, and prevents galling when the plugs are replaced in the future.

 

I also put some of that electrical jelly on the inside of the spark plug wires connectors upon attaching to the spark plugs. This helps seal out moisture, and prevent the wires from getting really tight on the plugs.