CivicRider

hi, I have 2001 civic lx sedan 1.7 which might have bent valves. I will do compression tests soon to confirm but if I had to go for a valve job what parts to order.
for air leak down testing, piston being tested needs to be at TDC right!?

scooty

The head needs to come off to determine the extent of the damage first. You might get very lucky and just have one or two bent valves, or you might get unlucky and have to replace a piston or two as well.

CivicRider

I will do that, but say if two valves are bent, I should order only valves, or guides, seats seals will also have to replaced even if they are good! I m able to start car but it shakes like crazy! I m not expecting major damage to engine but I do know that car was cranked while timing was off!

ezone

A "valve grind set" will have the head gasket, the other gaskets for the job, and the valve stem seals.

I'd replace just the valves that are a problem. Normally, guides are not cracked (but should be thoroughly inspected!). Seats are not a problem either.
Actually, I let the machine shop do this work. It isn't profitable for me to do it at work.

I'd do compression and leakdown checks before pulling the head so I know where to look after the head is on the bench.

I could back off all of the valvetrain to do the leakdown checks, that way it wouldn't matter where the pistons are, and you wouldn't even need the timing belt on it or turn the cam. ALL the valves should stay shut no matter what this way.



Leak checking the valves (with some low surface tension liquid) is done on the bench after the head is off.

HTH?

CivicRider

bad news, compression test results
1-- 0 psi
2-- 0psi
3-- 70 psi
4-- 0psi

couldn't do air leak testing
i will start taking things apart, then do fluid leak test while head is out! which low surface tension fluid is usually used?
does exhaust manifold has to be removed?

ezone

You got problems.
Yank the head.
There will be a bunch of obviously bent valves.
All 4 cylinders look like they will have bent valves, but I can''t tell you which ones.


You can check valve clearances, any that are bent will have suddenly developed a huge amount of clearance.

But the head has to come off regardless.

CivicRider

thanks ezone!

which low surface tension fluid is usually used for valve leak testing on table.
my exhaust manifold nuts are extremely rusted and I can't take them off so far. can I leave exhaust manifold connected to head or it has to come off to have valves changed?
thanks

ezone

Water based liquids generally have a high surface tension.
I would probably use whatever is laying around on my workbench.
If water gets through then you should know you definitely have a problem.

Gasoline is usually handy and has low surface tension. Don't burn garage to the ground though.

Blue windshield washer fluid (Methyl Alcohol + Water) has a medium tension.

Mineral spirits would be good, won't evaporate real fast, good for an overnight soak if you really have some not obvious.



You can take it off that way, sure. Makes it heavier and awkward though. Then take the manifold off on the workbench.

The 12mm nuts holding the manifold to the head should come apart far easier than trying to get the pipe off of the bottom of the manifold. Remove the bolt holding the small thick bracket to the block near the bottom of the manifold, then the manifold and the entire exhaust should move to allow the manifold to slide forward off of the studs on the head and drop down a little bit. I haven't had any problems this way so far, and I'm in the rust belt. I use air tools wherever I can get them to fit.

If any of the studs break off in the head, the machine shop should have no problems getting them fixed for you.

(I'm not a machinist, and I don't do the actual valve jobs. I diagnose, pull the head off, then send it to a trusted machine shop.)
HTH

CivicRider

thanks

so head is off to my work bench as of Sunday evening. I aligned timing marks on crank and cam before removal. on head cylinder 1 and 4 valves are closed and 2 and 3 are open. is it ok to turn cam shaft from cam gear pulley to close #2 & #3 cylinder valves to do leak down tests on them ?
will post photos soon
I had to use extractor sockets for rusted / rounded exhaust manifold bolts.

ezone

Yes.
You can turn the cam to wherever you want to right now, just be sure it is timed on the marks again before you set it on the engine later.

(While working with it on the bench, I set the head on a thick stack of towels or a pair of wood chunks on the ends so I don't damage any open valves. They are kinda flimsy.)

If you already know that you have to do valves, you may as well strip the rockers and shafts and all that off now. That will get all of the valves closed at the same time.

At this point, you can lay a straight edge across all the valves on each side and look for obviously shorter ones. Those will be bent.




BTW, if you have the cam timed on #1TDC right now, the valves on #4 are on overlap and may not be truly 100% closed. There must be clearance between each rocker and valve stem to be assured the valve(s) in question are closed.

HTH

CivicRider

To "strip the rockers and shafts" , which bolts need to be opened or loosened. i am attaching a picture so that i can understand it well instead of messing up.

i would love to have all the valves closed so that my leakdown testing would be easier.

Or is there anyway i can find out which valves should closed at what cam pulley position.

so i guess turning it clockwise wont hurt at this point

Thanks

ezone

The first step--the adjusters, valve adjustment-- will have to be done when you put it all back together.
I would go to step 2, loosen all the bolts that hold the 2 rocker shafts and let them rise until there is no pressure from any of the valve springs.

Valve action is only determined by the lobes on the cam.

Watch the valves and rockers as you turn the cam, if you don't want to lift the rocker shafts. Turn it 1/4 turn for each next set (cylinder TDC position) in the firing order.


You aren't going to hurt it now by doing that.

mikey1

it is probably cheaper and easier to just remove the head, bring it to a shop and have them refurbish the entire thing.....either that or just buy a used head

CivicRider

so , i ended up taking the camshaft off with rocker panels. It was much easier and reliable to make sure that all the valves were closed.
all exhaust valves were bent so replaced those. I rented autozone valve spring compressor to replace valves. It took me few hours to learn how to out prong of compressor into spring as they were way thick than spaces in spring.
Intake valves were not leaking with camshaft off so left those in place. (yes, i chose to cheap out to save money). I used WD-40 to check leakage. Ezone might like to comment on that.
put everything back together with new headgasket. fixed up the head on block
then connected all hoses, connectors ETC !(i am still left with 4-5 screws that i have to figure out where they would go)
so engine ran. smoke wasnt that great in start, but it become normal.
BUT oil started leaking under timing cover like somone opened a tap. i thought it is bad oil pulp seal but turned out that while tighting camshaft, camshaft seal wasnt put in right place so then fixed that. NO more oil dripping.
engine runs great !
some new codes popped up, one asked about IAC valve problem, other said misfires in cylinder 4 and 2. cleared the codes and they haven't came back yet.
does anyone know what is the torque on spark plugs, i might havent tighted spark plugs enough and that might be causing misfires. will clearn IAC valve this weekend.
i drove it around the block. i drove ok. no overheating.
will take it to a long ride soon and will let you guys know

ezone

No problem if they were not a problem. You only need to fix the bad ones, right?
Why? If it was handy and it works, no problem.
That's not something on my workbench at work though.
The NGK website has some handy advice on this.

http://www.ngksparkplugs.com/tech_su...x.asp?mode=nml

If you got the correct NGK plugs, you have "flat seat type with gasket", 14mm threads, and the head is aluminum: 18.0~21.6 ft/lb




Heck, it runs! Yay!

HTH