Mazda saying can't JUST do valve seals?

[Daninski]

I'm gonna post a little write up on how to change the valve stem seals without removing the head. In case other people are cuious abou thow its done.

Didn't happen to get around to that write-up yet did ya?

[Skuce]

Filling the combustion chamber with rope (through the spark hole). The cranking the engine by hand to mash the rope against the valves.
That's the only sure way to NOT drop a valve when you are changing seals, with the head still on.

Buy a "lever style" valve spring compressor. It's the only easy way to do it.
Unless you get the Snap-On/Bluepoint "Keeper remover" for $50

I've changed all the stem seals in my BP. Took about a day just because there are 16 HLA/keeper/retainer/spring/seal assemblies in the engine.

Get VITON seals too. Don't get the stock rubber ones.

[Daninski]

I thought there was a tool to do the job with the heads in place?

[hgallegos915]

Dealers always want more money.. thats what they are in business for.

My friend ivan replaced the seals on his ze and it was fine.


Until he boost spiked and blew the thing, totally unrelated.

[SuperK]

You know, this happened to my mx-3 when I had the stem seals done. I took the head off and into a head shop, and wouldn't you know, new seals and head gasket and the sucker blew so much oil by... You could look in the combustion chamber and just watch oil seep on the face of the piston while cranking the engine.


When we removed and reinstalled the head, the torque removed/applied to the block disturbed the already weak piston rings. This caused them to seat slightly differently and poof! out comes the oil into the combustion chamber.

So doing the seals without removing the head is a good option. On the flipside, if you remove the head, do the seals, and have your car blowing oil still, then it wasn't your seals all along and the bottom end needed some rebuilding as well.

[Daninski]

Has anyone found those additives that are suppose to soften seals to be any good? The Dealership told me to add two at once on a MPV I use to own.

[Tunes67]

I'm gonna post a little write up on how to change the valve stem seals without removing the head. In case other people are cuious abou thow its done.

can u do the same on a K8 ?

Replacing the valve stem seals on a K8 with the engine in the car would be almost impossible. At least on the rear head.. no way to get to the valves unless your a very talented contortionist If you remove the rear head then you could replace them and reinstall the head. That is doable but still a lot of work. Lots more valves to work with on the K8 Btw.. I completely agree with wytbishop. Replacing the valve seals alone wont change the compression or affect the piston rings at all. Removal of the head.. well if the engine is in bad shape.. eh.. maybe that could cause issues.. stranger things have happened. I always recommend replacing head bolts too.. or at the very least.. use a tap n die set to clean both the bolts and the bolt holes of the engine block prior to reassembly. Nasty threads WILL change torque specs. You might think you have only applied a certain amount to the bolt when retightening.. but it could easily be more or less or the torque could relax after the engine has heated up and cooled down a few times. Its not cheap to replace them and certain engines actually Require it when doing a head removal/replace. Shop manual should tell the tale there.

Tunes67