I gotta replace my injector seals so while I do that I'll be checking my valves. Is there any coating on the valves that a chemical may eat off? I got a heavy duty degreaser at work we use to clean metal, this crap can strip paint and if u spray it on plastic it melts and eats the plastic. Wanted to give it a try on the carbon if there is nothing to damage on the valves. I'm sure it would work within a few minutes to soften it enough to brush off

 

You've got to be careful,
Because it'll be easy to let that run down on top the valve and get into the engine, and the carbon coming off isn't good if ingested

 

The good thing is this stuff is like brake cleaner, it evaporates after 5 minutes

 

The gm stuff you can get from the dealer is very good. It's "gm top engine" cleaner. Just make sure the valves are completely closed when you let it sit. Walnut blasting a lot easier rather then trying to brush it off.

 

Tom, get yourself a set of pics, ( like at harbor freight) you will need then to reach behind the valves. I let mine soak overnight in seafoam and it loosened it up. But just like someone else said, make sure your valves are shut. You will probably have i cylinder that inst closed.

 

Idk if it will need it yet, motor only has 25 k Kms on it and I got the Powell oil separator now. Hope not. But I shall get picks just in case. Walnut blasting just seems like a pain . I'd try cleaner first

 

Wait I do have picks set. That's solved then

 

using chemicals that can hurt the rings is not a good idea. walnut blast is not expensive ; as long as you two ports at a time 1 & 4, 2&3 with the appropriate pistons at tdc you will be good, and walnut media will burn and not hurt the motor....chemicals? can leak past the valve seats. So like most things, do it right the first time...

 

yupper.

 

How do you get the back side without using the soak and scrape method
Im sitting at almost 94k I need to do this soon

 

I did the walnut blast with Powell, well worth it $ wise I'm at 90k KM the car feels like new again and got his PVC upgrade to stop it from happening again

 

I made a special tool so my blaster can reach in and it has qwik change tips, so I have a long curved tip to get to the back of the valves. I also use some fine long piks as a check tool ( harbor freight, as already posted and suggested on here by a member - I forgot who- they posted up and had done a very good job at this) But the bottom line is it is mostly a relatively easy but time consuming job. On Dutchman's LNF his PCV valve was totally not 100% and I replace that valve anyway as SOP.

I have found the coked material is not that hard in itself. Its kinda like a soft plaque, and the job I do is roughly like a dentists job, masking all around the port to be cleaned.



Dutchman's ports looked like this when I was finished.


Its amazing to me the cars run at all with coked up valves; the ports are so small due to the buildup, I can certainly see where there would be a performance drop off.

Toyota currently now have some DI engines with 8 injectors, 4 DI and 4 port fuel. And there may be something to running that ZZP fifth injector, if the fuel distribution gets to all the ports... and certainly the way the Powell PCV upgrade seperator is doing its job is most gratifying for me; its important that the products we devise and sell, work.

I also dont want to share to much on how I do things anymore, the vendors copying stuff gets old...

Thanks Dutchman for coming by and visiting the walnut dentist....