Installing 4g63 top end back on after a head gasket replacement

[Ghosted]

Ive done some pretty through searching and cant seem to find anything that relates to what Im looking for. Maybe I have a term wrong ???

Im installing a new top end back into my 4g63. I have no idea how to set the bottom end (outter pistons up, or inner postions up?) before I put the top end back on. How should the top end be set to make sure everything work.
Im not a noob, but feel this is a noob enough question to warrant this forum...

Some pics here (the top is just sitting, not bolted)
http://www.cardomain.com/ride/3204307/2

I never took off the pistons or the rods. Just the top end. I cleaned the bottom end the best I could.

Im trying to install the top end back onto the bottom end.

The bottom end hasnt been touched, (I turn the pistons with a wrench on the crank)(I just cleaned it)
I assume I need to have the pistons in a specific position, (2+3 at the top? 1+4 at the top? all 4 equal?)
as well as the top end rotated to the right position before I put it all back together(rotate the cams a certain degree or angle?)

 

[SrKegler]

Rotate the crank around until the lower timing mark is lined up. Then rotate the crank counter clockwise a little until all the pistons have dropped down in the bore some.

Rotate the camshafts until the dowel pins are up and the timing marks are aligned. Without the timing belt on, the cams marks won't stay in place. Exhaust will be a little higher and the intake will be down a little.

You can now install the head. Rotate the crankshaft clockwise until your lower timing marks are lined up again and install the belt. You will only be rotating the crank a little, the same amount clockwise you moved it counterclockwise earlier. Don't spin it in a full circle or you will bend some valves.









You always have valves that are open when the cams are installed. Don't want to take a chance on bending valves by rotating

 

[steve]

That's exactly what you do and then follow the VFAQ to put your timing belt on and tension it.

 

[Ghosted]

Yeah Ive noticed that i can only go so far in either direction. So thats the key, to turn it counter clockwise as far back as you can (without pushing it) than allign them up with the timing marks.

Put the top on, make sure the marks are at the top and than crank clockwise one spin until they align again....correct?

 

[SrKegler]

NO!!!

Before you put the head on, align the cam gears. With the head still off, turn the crank until the timing mark on the crank is aligned. Then rotate the crank backwards until you see the top of the piston slide down in the bore. You only need to turn the crank backwards maybe 1/4 turn. Just enough so you don't take a chance of a valve hitting the head.

After that you can then put the head on and turn the crank back clockwise to realine the timing mark.

Never turn the crank past the timing mark while the belt is off.

 

[Ghosted]

Ok, Im sure I got it now. I drew a picture!

can anyone give me confirmation that this is what he means..

 

[steve]

Pretty much, you can also just stop before you reach TDC. All your trying to do here is make sure that your close to TDC when you start out but not at TDC to give the valves some room when you bolt the head on. Once you have the head on and the cams are lined up you can turn the crank to TDC and not hit anything.

Another option is to lock the cams in time before you put the head on. Jay Racing makes a nice plastic lock to hold the cams in place.

You can also do the same thing with a bolt and some washers to fit between the teeth of the sprockets, tighten the bolt up and they won't move.

 

[knochgoon24]

I've never seen or heard of that trick to lock the cam gears before. Nice.

 

[steve]

I made some using wooden dowel instead of the washers and later found that on 3Si and though it was pretty much the simplest solution.

For those paying close attention, that's where the timing marks go on the front bank of a 6G72. You pretty much have to use some sort of lock on the cams or you'll spend your afternoon cussing with bloody knuckles as the exhaust cam won't stay put and snaps back if you look at it funny.

 

[HareyCarey]

Is there an in depth how-to on doing a head rebuild with step by step pictures? I've done numerous searches as I am in need of a rebuild, yet I have found nothing to my satisfaction. Perhaps I have overlooked an article? I have this thread bookmarked for when I do my rebuild.

 

[steve]

Is there an in depth how-to on doing a head rebuild with step by step pictures?

I don't believe there is an all inclusive head rebuild thread. You should try looking under the Tech menu and read all the VFAQ's on the various aspects and check the DSM FAQ's under the same menu to see what's there.

 

[HareyCarey]

I will recheck, thank you. Another quick question: I am a novice at mechanics and have never done a rebuild before but I have the service manual and access to all the tools, should I attempt it on my own or send it off the first time?

 

[SrKegler]

Heads aren't that difficult unless you replace the valve guides. Once you replace the guides the seats have to be cut to center the new valves.

Otherwise, the only problem is finding a valve spring tool that will fit on our heads. Best method I've read about is making one out of a c-clamp and a spark plug socket then cutting a slot in the socket to remove the retainers. I've got old 02 sensor sockets that should work, has the slot already cut.

In my opinion, with all the work involved checking spring heigth, spring tension, removing/replacing valves, etc, I'd rather just pay a reputable maching shop to do the work.

Do a search for the name BogusSVO on here. He has some pretty good articles on head work just to give you an idea of what is involved. Lot more involved than just pulling the old valve out and throwing a new one in.

 

[Ghosted]

I have a stock turbo. A whole bunch of new parts though, i have them listen on cardomain. My main objective is to get this car running asap and get it painted. I eventually plan on installing a 6 bolt bottom end so Im not going to turn it up yet.

I have a haynes manual as well actually. Been using it as a reference, but theres some stuff I really just make to make double sure of before it all goes back together.

I have spent 2 days cleaning the block with wd-40 brake cleaner, and various others,
prepped it with a little bit of engine oil to keep it nice
after turning it clockwise as far as I could go without pushing it I Set the timing, (just the one cranked with socket wrench (turned it back just a hair for clearance), the second one above to the left of the main dial. and then just turned the dial by hand on the third lower one to match up.

I have made sure the head is alligned properly, using a bolt to hold it in place, it was surfaced before I bought it and was always kept in bubble wrap.



So before I put it all on and start tighening it down (i understand tightening specs 1-16-8-15-2**ok not 16 bolts but you get the idea** and so on, and tighten 30-60-90 (some say 100 after 90)

Who uses a sealant on

Quick question

QUICK QUESTION

Im lining up the timing marks for the bottom end. How far should I crank it? It I go cw, and keep going it starts to turn the wheels?

 

[steve]

QUICK QUESTION

Im lining up the timing marks for the bottom end. How far should I crank it? It I go cw, and keep going it starts to turn the wheels?

Is the car in gear?

You don't need to move the crank far, just enough so the pistons aren't at TDC in case your cams aren't lined up when you put the head on so you don't try and bolt it down with the valves open on the wrong cylinder and have them hit the pistons.

 

[Ghosted]

Got it, the car was in gear, just a stupid mistake.

Im in the process of installing the top end now!

 

[BogusSVO]

from what issues you are having with setting the time belt, I would have to recommend that you have your head done at a decent machine shop.

yes you may be able to get it apart, and even back together, but being albe to check guides and springs may be a little beyond you at this time.

read thu this info and see what you understand....
Thanks agin to DSM Wiseman BigWoo for this write up
http://www.dsmtuners.com/forums/articles-engine-fuel/303225-engine-machine-work-explained.html

http://www.dsmtuners.com/forums/cyl...how-aluminum-head-pressure-tested-cracks.html

http://www.dsmtuners.com/forums/newbie-forum/341287-how-test-valve-springs.html

http://www.dsmtuners.com/forums/newbie-forum/341209-4g63t-valve-spring-info.html

http://www.dsmtuners.com/forums/articles-engine-fuel/341627-how-check-head-warp.html

http://www.dsmtuners.com/forums/cyl...0613-why-not-let-your-head-belt-surfaced.html

http://www.dsmtuners.com/forums/new...face-4g63t-cylinder-head-mls-head-gasket.html

http://www.dsmtuners.com/forums/newbie-forum/341218-how-change-valve-guides-4g63t-head.html

http://www.dsmtuners.com/forums/newbie-forum/341028-4g63t-head-oil-port-mod.html


all the above links you should read so you will have an understanding of what you are trying to do.

 

[Ghosted]

Oh i should have explained earlier. I actually bought the head off of an experienced builder all put together. So i dont need to mess with any lifters or springs or anything like that. I put the head on today, and feel confident that I have installed it correctly. Everything lines up thus far. I guess the next step would be to get that timing belt on there asap.

BTW Thank you BogusSVO, I have read the links, and have bookmarked them as well for future reference!

 

[nek]

Is this,

You don't need to move the crank far, just enough so the pistons aren't at TDC in case your cams aren't lined up when you put the head on so you don't try and bolt it down with the valves open on the wrong cylinder and have them hit the pistons.

why you said this?

Don't spin it in a full circle or you will bend some valves.
You always have valves that are open when the cams are installed. Don't want to take a chance on bending valves by rotating

When your cams are tdc, arnt all valves closed? Or maybe valves in 2+3 are closed and 1+4 are open?

Sorry for thread revive, just enjoy haveing full understanding.

 

[steve]

Nope. At TDC on cylinder 1 pistons on 1 and 4 are all the way up and the valves on cylinder 4 are open in overlap (both the exhaust and intake valves are part open). You can work out the rest of the cylinder strokes and which valves are open yourself.