Removing Wiring Harness.... Need Help(Changing Head Gasket)

[XxBLiNdxX]

I'm in the middle of trying to dig down into my block and get down to the head. I'm at the point where you remove the wire plugs from most of the components but they each have a lock device on them making them impossible to remove without breaking the tab. Is there some sort of special tool to remove these wire plugs from the block? If so where can I purchase one and what is the name of it? I have a 90 240sx

[NISTECH]

If your talking about the squre plugs with the steel metal lock clips, I use a 90 degree scribe to lift and slide the metal lock out of the connector. I bought a variety pack from sears for like 3 bucks.

[Touchdown038]

Anything small.... flathead screwdriver works best for me.

[XxBLiNdxX]

I tried a flat screw driver, thats how I started breaking off the little tab you have to get the clip over. I have tried many things, but I am in fear of breaking all the tabs on the backends of the connectors. Would that affect the connectors ability to stay locked on if those are missing? Are they just there to deter DIYers. I've noticed a couple other connectors has the tabs off from previous repairs that I didn't do.

Well anyway's in a few days I will be getting into the cylinder head and was wondering if you guys had any recommendation, besides taking it to a mechanic, on what I should be doing. I'm just guessing that the head gasket needs to be replaced since the oil that is coming out of my car is white and my reservoir is losing antifreeze. One day I started to leak oil from the oil pressure switch and then the next day I have white oil. This will be my first time doing any big repair to my 240 other than replacing the brake booster and master cylinder, so any help would be great.

I purchased a head gasket set off of ebay. I believe I have all the gaskets needed to do the job but I am unsure of what gaskets will need sealant and which ones wont. I know the valve cover gasket is silicone and the head gasket is graphite. It's a APEX Head Gasket set if that will help any. I have a 90 Nissan 240sx with the original KA24E Engine in it, with 140k on it.

Any help or advice anybody can give me will be great. If needed I can provide pictures of whatever, as I am taking them for pretty much ever step I do so I dont get lost. Thanks for listening to my sob story. =)

[NISTECH]

the retiner clip always breaks on those connectors , as long as the metal part wil slide back in and hold the connector on you will be fine.

Do not use any sealer on the head gasket at all, take note of the points on the v/c gasket where sealer was applied previously, those are the only points requiring sealer.

When you pull the head off be sure you have a flat surface on both the head face and the blocks deck, use a straight edge to do this, if there is any warpage on the head send it out to be machined. The block shouldn't have any warpage.

you can get away with out removing the intake manifold from the head when you pull it as long as you have a friend to help you lift it. Be sure to not ever lay the head on its face while its off the car, you could scar it or bend a valve if you do. also make sure all your timing marks are lined up before you pull the chain off.

[XxBLiNdxX]

Ok get this..... not to sure what to do about this and any opinions would be great. I take off the heat shield, at least unbloted it because I can manuver it out yet, and I hear a bolt drop. To my suprise the exhaust manifold on the left side only has one bolt on it and some kind of rod shoved into one of the ports. This had to be done by some mechanic because I have never under my ownership down any work around that manifold. See picture attached.

Also in my Repair Manual it says to torque the intake manifold and the collector to 1215 ft. lbs. from the center owkring to the end , in 23 stages. Thats some kind of weird typo I would think?

Here is picture of exhaust manifold.

[NISTECH]

Also in my Repair Manual it says to torque the intake manifold and the collector to 1215 ft. lbs. from the center owkring to the end , in 23 stages. Thats some kind of weird typo I would think?

LMAO 1215FT lbs in 23 stages...LMFAO The torque wrench would have to be 10ft long.

I think its suppose to read 12 to 15 ft lbs in 2 to 3 stages.

[NISTECH]

where is this rod your talking about?

[XxBLiNdxX]

I guess it is a little hard to see..... sorry. Here is another picture with arrows and comments. Notice how there is a rod shoved up into the place where a bolt would be, and then the bottom part should have a thread for a nut just like the other ones. I'm not sure what to do here.

[NISTECH]

thats not a rod, its a broken exhuast stud, that side gets a nut. what you need to do is completely remove the manifold from the car and extract the stud from the head. I suspect the bottom one is the same way and has a stud broken flush with the head.

[XxBLiNdxX]

How do I set TDC at position #1 and when I take the head off is there some kind of cleaner I can submurse the head into, to remove all the build up inside and out? Just so you know this is what I am dealing with.......here is the rocker cover.


Modified by XxBLiNdxX at 4:10 PM 4/24/2005

[XxBLiNdxX]

and head.....also where would I be able to pick up a bolt and a thread to mount the exhaust manifold. Someone tried to drill out one of the bolts but seemed as though the gave up 1/4 of the way through....=(

[NISTECH]

there are some threads on here that show where the marks should be on TDC, also try the 240sx.org FAQ section There are several writeups in there on doing this work.

[NISTECH]

also when you take it to the machine shop to have it milled or pressure checked you can have them extract the broken studs as well.

[XxBLiNdxX]

Sorry to bring this thread back up but I figured its better than starting another one.

So I pulled the head today and one of the head bolts were covered in black oil and smelt like burnt rubber. The rest of the bolts were perfectly clean. Note that all the oil when I drained it was white. The head gasket look perfectly normal to me besides where the bolt was at. Does this mean I have a cracked head?

Here is a picture of the head gasket.....

[NISTECH]

you have the front cover off I assume, take a look at the inside near the water jacket and see if the chain ate through it. Its hard to tell if the gasket is damaged by that picture.

[fallen180sx]

shoulda gave it a compression test before hand.. it looks like the 4th cylinder would be low (looking at the gasket) it looks like a rat was eating on your top left hole. What mine looked like and mine was blown..