Project!!!

[Datsunrider71]

Going to change my head gasket in a few days any thing I should know before I start doing it!?

[Datsunrider71]

It's on my L16

[athoose]

IBH

 

[laotsu]

yeah, you gotta wear a dopey Karate Kid style bandanna when you do it.

[thatguy]

And listen to "turning Japanese"!

[Tristin]

And post in the right section...

 

 

Edit: I see its been moved. Good luck.

[Ratwagon1600]

The Hainz video is a good start.

 

Try typing "head gasket change" into the search function, top right of the screen.

 

Theres heaps of threads which will give you all the edumucation to do this.

 

After you've read all that and watched the vid, if you get stuck post a question in the engine thread and someone will chime in with the advice.

 

Good luck!

[datzenmike]

Going to change my head gasket in a few days any thing I should know before I start doing it!?

.

 

Above all else. Be sure to block the timing chain before removing the cam sprocket to prevent the chain tensioner from falling out. Add an extra half day to fix this if you don't. Find out how if you don't know.

 

Loosen the cam sprocket bolt but don't remove yet. Now set the motor to TDC compression on #1 cylinder. Set e brake and place transmission in neutral to prevent vehicle movement from bumping the crank off TDC.

 

Mark the sprocket and the chain so that it can be put back in the same alignment.

 

There are two 10mm bolts at the very front of the head that bolt down into the top of the timing cover.. don't forget them

 

Take the fuel pump off. Remove the distributor cap so it doesn't get broken... put a baggie over it.

 

Drain a gallon of coolant out, at least, and store where the dog/cat can't drink it.

 

If possible drop the exhaust down pipe and lift the head with both manifolds attached. Less work, less gaskets needed and less chance of breaking a stud or having a leak. Be sure to collect the two alignment 'dowels' they may remain in the block or the head and look like half inch long pieces of 1/2" copper water pipe. You'll know when you see them. You can leave the carb on if you are careful but you risk stirring up sediment in the float chamber. If carb is left on...tilt head just enough to clean any gasket material off the surface. I like to use a brass bristle wire wheel on an electric drill. Take your time and don't force it.. the aluminum is soft. It's impossible to have it too clean

 

Head bolts are totally reusable if undamaged. Wire wheel them clean, inspect and wipe down with an oily rag.

 

The block surface and threaded holes must be clean. It's impossible to have it too clean.

 

Do NOT use any kind of gasket shellac, glue or sealer . This isn't the 1940s. Gasket goes on dry just like Nissan did when it was new.

 

Don't forget the steel washers under the bolt heads and put a drop of oil on them.

 

Torque the head bolts in this sequence to 20 ft pounds, then again, in sequence, to 40 ft. pounds and a final sequence to 60 ft. pounds.

 

RAD

7..8

3..4

1..2

5..6

9.10

[LenRobertson]

Is there any chance the gasket needs changing because the engine was overheated? If so, the head could be warped and must be planed flat by a machine shop. A new gasket won't seal if the head is warped. Not trying to scare you, but just something to think about if you know the engine did overheat. If the gasket had just died of old age, or you want to change it for piece of mind, then a new gasket should work fine.

 

Get a Fel-Pro or Nissan head gasket. If you already bought a gasket kit of another brand, use that head gasket for a wall hanging and buy a Fel-Pro or Nissan one.

 

Don't mess with the bolts holding the cam towers down. You don't need to touch them.

 

I've pulled several heads using a straight piece of 10mm allen wrench in a 3/8" drive 10mm deep socket. It has always worked, but every time I expect the socket to break and send me flying. I need to get a 1/2" drive 10mm allen bit socket and I recommend you do the same.

 

I've read you should loosen the head bolts gradually in the reverse sequence of how they are torqued when installing the head. I don't know if this matters, but it easy to do, so why not?

 

If you have head bolts that are hard to turn, it is probably worth spraying PB Blaster under the head and hope it soaks down to the threads. It might be better for the threads in the block if even a little Blaster gets down there.

 

Depending on how clean the threads in the block are, it may be worth using a tap to clean the threads (after the head is off}. There is a trick of grinding a burr on an old head bolt to make a thread chaser, but if you don't have an old bolt, buying a tap will be easier. I'll post the tap size if I can find my tap. Often some of the block threads have rust or carbon down them and should be cleaned out.

 

If for some reason you decide to change the manifold gasket too, you will need a 3/8" drive U-joint to get to a couple of the nuts under the manifold. Wire brush and Blaster the nuts you can get to to make them easier to remove.

 

I seem to remember reading of cleaning the block and head surface with acetone, but don't do this unless someone else posts that this is a good idea. I may be think of the wrong chemical. Wear chem proof gloves when messing with the acetone. Brake cleaner might work instead.

 

I don't know what everyone's thinking is on what to lube the head bolts with. I think probably just motor oil. Or does that carbonize with heat and make the bolts tough to remove? Is no-seize compound better?

 

Len

 

 

[Datsunrider71]

Thanks guys...

 

 

I just drove here and she getting hot but it didn't reach h she just stayed infront of the p.

 

my poor baby is sick :(

[LenRobertson]

I drove my 510 with the original 1600 most of one summer with a head gasket getting steadily worse. Toward Fall, I was adding coolant on a daily basis and the temp increase on the 13 mile trip kept getting a little higher.. Finally coming home one day, the needle climbed higher and faster, and I decided it was time to give up on that head gasket. I knew I didn't want to have it boil over and warp the head.

 

But that led to swapping in an L20b and 5-speed, which was a fine idea, but took me years. I really should have just replaced the head gasket on the 1600 and kept driving it.

 

Len

[Datsunrider71]

That's what's happening to me bro smh, when it was colder out it only heated up just a lil passed the normal temp, but now she heats up quick :/

[LenRobertson]

Changing your head gasket sooner is probably wise. I was pushing my luck running mine as long as I did. But my commute is a country highway, not in traffic, If the temp had gone too high, I could shut it down and walk.

 

Dunno what predicted temp for you are there in MA next week, but here in WA it is supposed to hit 100F or so for a few days. I hope it is weatherperson hype. If not I'll find out how my SX likes hot weather. It will probably handle it better than I will.

 

Len

[Datsunrider71]

Fuck that I'm not diving her if that happens..

 

 

 

I hope you SX can stand that

[datzenmike]

High temp could be the gauge. If the gasket is the cause there should be other symptoms. Doctors don't do brain surgery for a headache.

 

Does it use coolant but you can't find any reason for it?

Are one or more plugs mysteriously cleaner that the others?

Is there a cylinder or two adjacent cylinders with slightly lower compression?

Does the coolant have a gas smell or oily film?

With the rad cap off, if you rev the motor hard, do you see air bubbles a short while later?

Have you checked that your ignition timing isn't retarded?

Do you have tight clearance on any exhaust valves?

Could your carb be running lean? Part blocked jet?

Are your plug porcelain insulators white around the tips?

[Datsunrider71]

To be real with you idk if the compression is off I will have to check that.

 

No oily or gas smell but their always some white crap on the rad cap every time I open to add coolant because the coolant gets spit out, bubbles I don't know I would have to check later when I get home and tell you if it happens.

 

I will I know if it's the gauge??

 

I don't think so how will I know if the ignition

timing was retarded?

 

 

Are one or more plugs mysteriously cleaner that the others? What to you mean here

 

Valves are lose

 

The carb is acting up on me so it could be a jet I know it's tuned messed up I'm trying to tune it but I can't get the sweet spot

 

Are your plug porcelain insulators white around the tips. what r those?

[tr8er]

Mike is suggesting you pull your spark plugs to look at the tips.  If coolant is getting into one or two cylinders, you will see major variance in coloration.  You can tell if your carb is proper as well by looking at those plugs.  Worth reading up on.  

[Datsunrider71]

I took them off the other day to regap them and the wet with gas.

 

Where can I read up on that

[Datsunrider71]

 

 

That's what I'm talking about

[hobbes_the_cat]

That looks like milkshake to me. That means oil is getting into your coolant. That is almost always a sign blown head gasket.

[Datsunrider71]

Okay bro I will change it thx