Machine Head: Pros/Cons - "While I'm in there"

[Jdub]

Background: I have a decently loud ticking/missing every once in a while. To be honest the missing is not really noticeable at all while driving, its only noticeable to the guys at the shop -- apparently while their ear is near the engine listening closely, and possibly the cause for a slightly shaking engine at idle. (Plus this is my first m20 so I don't really know exactly these engines are supposed to run when they're running properly)

I have recently replaced: cap and rotor, timing belt and tensioner, spark plugs, plug wires, adjusted valves (multiple times: 3)

With all that being said:

The guys at the shop said I need to have my head machined and I need to reseal a bunch of stuff. They said the worn seals are the reason the valves aren't closing properly leaving room for misfires.


1. What are the pros and cons of machining a head
2. Is it likely to improve performance/fix ticking issues and misfires?
3. I want to boost in the near future, so would machining, replacing the head gasket/o-ring the head be a smart investment anyway?
4. For a guy who who hardly ever turned a wrench on a car, but figured out how to do a timing belt, would it be unwise for me to try to take the head out myself and send it in, or should I leave a job like this to the shop?
5. Is there anything I should do while the head is off?

I know thats a lot, and I have spent time researching but can't seem to find the specific answer to the question, hoping you guys can help me out!

PS: They want to charge $800 for labor, Im not sure if this includes the $250 machining cost they mentioned. need to get new ARP bolts and all the seals too. Im assuming the total cost will be around $1500 or so when its all said and done.

Also willing to hear from anyone who has advice for best bimmer shops in Orlando.

[digger]

Read this thread.

http://www.r3vlimited.com/board/showthread.php?t=380845

It's hard to say without hearing it idle in person but it might be pretty normal mine was not butter smooth at idle but drove fine. There is nothing wrong with a head job but there could be nothing majorly wrong fwiw. There are probably about a dozen or so things I'd look at before yanking the head

A good mechanic can diagnose things and say for sure its valve sealing issue with leakdown test etc

[TobyB]

They said the worn seals are the reason the valves aren't closing properly leaving room for misfires.

Hmmm. Loud ticking occasionally can, indeed, be a valve sticking.
But are you burning a ton of oil?
Because I've run some engines that eliminated the mosquito population
in the entire county and those valves didn't stick...

They might be right, but I'd go get a second opinion, and a few more details, personally.
usually you only machine the head when it's not flat, and the only way
you can tell that is by taking it off first. So unless they're saying your
head gasket is gone, I'd be skeptical.

t

[Jdub]

Thanks for the advice guys, I went and got a second opinion and he said that the ticking I was hearing wasn't out of the ordinary. I ran seafoam through it early on and I needed to change the oil so I did that and put in 20w50, much thicker than the 5w30 that was previously in it, and it seems to be helping a bit!

My next project is now getting the stereo up and running (bypass the amp), and I need new tires badly (hoping to make that a wheel and tire combo) :)

Im hoping when I move up to Denver officially I'll make some friends in the e30 family up there and someone might be willing to show me the ropes on a turbo build.