[GK13]

so, this seems to be the last thing on my list for a little while. after I take the plastic off, how easy is it to do my own valve adjustment? I'm no familiar with engine work, so this would be my first time. would it be better to just have my mechanic do it?

 

[Buffalo]

It's not a difficult thing to do on the 03-06 400 because of the type of adjusters it uses. If you know the basics of how to use a feeler gauge then it's just a matter of taking enough parts off to allow you to remove the valve cover then using a feeler gauge to check the gap. If it is out of spec then you loosen a lock nut and turn a screw to get the gap right. Once you have it right you tighten the nut back down and button everything back up.

The only touchy part is that you need to have the engine at top dead center on the power stroke before you check the gap. There are alignment marks to align up so that you know it is at the right spot. A service manual is a good thing to have to show you how to do that. If you don't have it I believe there are some videos that show the procedures.

 

[oakcreekeric]

I may add...

Make sure you are at top dead center at the top end of your stroke (intake), not top dead center on the downward stroke (exhaust). You can put a pencil in the spark-plug hole and watch it come up, and then down. You need to insure the pencil is at the top. If you do it based on the markings (per the book), you could inadvertently forget to make sure it was at the top, not the bottom.

I made the mistake and adjusted my valves incorrectly. It wasn't a major issue, just a royal pain-in-the-a$$ since you have to almost put it all back together to test it.

I got fed up and took it to the shop, it wasn't very expensive (around $150).

Good Luck !!

 

[John Holbrook]

Would it start when you adjusted it on the exhaust stroke?

 

[Buffalo]

Making sure you are on the power stoke is pretty simple if you have the valve cover off. Just watch the valves and see if the intake valves are closing as you turn the crank to get the alignment marks even.