millball

You're getting distracted and wasting your time.
Check the valve clearances and adjust, if necessary.
If that does'nt correct your #1 cylinder problem, the head will have to come off in any case.

jereli

Thanks for everyones responses i been learning a lot with everyones input.

But yea I will remove the cover when I get a chance and check clearance.

jereli

Do I need to drain all the coolant from the radiator for removing the plenum? Is there a way I can drain some of it so that I won't spill out when I take the plenum off?

oldblue

i wouldn't worry about draining it. you won't loose much, if any, coolant. i think the only coolant lines to remove are the hoses on the throttle body, and you could just unbolt that from the plenum and leave those hoses attached.

jereli

So I removed the valve cover only the passenger side and now not sure how to check clearances. I got a PDF guide from a user here that i am un familiar what guide it is but it starts on page EG2-18 for valve clearance and inspection. It says to start on TDC for cylinder one and starts by checking the driver side. I don't have that cover off yet. Do I need to start on driver side?

millball

Just turn the engine until the cam lobes for #1 are up and the base circle of the cam is toward the lifter pucks.

jereli

Okay got some values.

PASSENGER
Cylinder 5
In= .203mm (.008in)
Ex= .203mm (.008in)

Cylinder 3
In= .203mm (.008in)
Ex= .178mm (.007in)

Cylinder 1
In= .152mm (.006in)
Ex= NO GAP

DRIVER SIDE
Cylinder 6
Ex= .127mm (.005in)
In= .127mm (.005in)

Cylinder 4
Ex= .152mm (.005in)
In= .178mm (.007in)

Cylinder 2
Ex= .127mm (.005in)
In= .178mm (.007in)

millball

Well, the first thing is to restore some clearance to #1 exhaust valve and see if decent compression value is re-established or not.

jereli

Almost all of them appear to be out of spec according to my Haynes guide. Should all shims be replaced?

How would I restore clearance, smaller shim? I would think I would need bigger shims if anything.

millball

Smaller shim. (thinner)

Sometimes, after all clearances are measured and carefully recorded;
All shims are removed, keeping track of their positions in the head, and the shims are measured with a micrometer for their thickness.
Shims might then be swapped out to other buckets to give more correct clearances.
In this way, not all the shims may have to be replaced, although you will likely have to buy some.
At this point though, you should just work with the #1 exhaust valve to give it some clearance so you can see if compression can be restored.
Maybe yes, maybe no.
If giving the valve back its clearance does not restore good numbers, the valve is likely already burned and the head will need to go to the machine shop for overhaul. The shop should adjust all clearances at that time.
Most machine shops I know don't change out pucks to adjust clearances when they overhaul these heads; they just grind the end of the valve stems to get the clearances right.

scope103

I agree, but steel yourself for bad news. The exhaust valve is cooled by sitting tightly to the valve seat, so if it has been propped open, however slightly, it will overheat and pieces will just break off the edge.

But the only way to tell for sure is remove the head and look, so there is no reason not to try adjusting the valve first and hoping for the best.

jereli

Thanks. I will try removing the shims.

Wouldn't there be something going on under the shims that is keeping it up high not allowing any clearance? I am trying to understand how the shim could be to big now. I will try swapping the shim with another one.

millball

The valve wears itself into its seat over time, effectively making the valve stem longer and thus making the clearance less, and exhaust valve stems often stretch in service, causing the same trouble.

jereli

Aah I see makes sense now. Will give it a shot tomorrow.

jereli

I decided I am gonna just pull the head off instead.. The valve is most likely no good and will have to be fixed. I am gonna just pull both heads out and have them both checked out and re shimed. Seems like it's gonna be a pain.

millball

I think that you have chosen wisely.

How many miles on your engine?

jereli

220k.. Not sure of the history on it. I just recently got it.

jereli

Having issues removing the exhaust cross over pipe..there's a nut on the passenger side that I just can't get off...really hard to break loose and no space.

jereli

Is there any special way of removing the nuts from the cross over pipe? ... I managed to get two out but the rest are super tight. Cannot get them to break loose at all!

millball

Just some brainstorming:
Curved, swivel head specialty rachet?
Penetrating oil.
Remove tranny crossmember and lower engine/tranny assembly to get some more clearance for tools.
Remove both heads at the same time with crossover still attached.
Universal hot wrench AKA acetylene torch.
I haven't had to part mine yet. Good luck!