3B Head removal (85 BJ70)

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bj70alex

Joined
Feb 28, 2003
Threads
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Location
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About a month ago I decided to replace the valve seals and found out that my exhaust rockers and valves are in pretty bad shape. So instead of just replacing rockers, i decided to pull the head and do the job right. I plan on keeping her for a long time. Before pulling the head, i decided to spray PB to loosen some rust on some bolts for a few days, espesialy exhaust manifold and visible head bolts.
After I removed the exhaust heat shield, the last stud with nut, the one near the firewall on top of manifold was laying between the head and manifold. I had a tiny exhaust leak on startups, now I know where it was coming from.

It's rather difficult to spray the PB onto the bottom bolts of the manifold.
First question, can the stud be fixed or ??????
Second, can I pull the head with the exhaust manifold, just by disconnect the downpipe and then worry about the removing the manifold.

Thanks,
Alex
 
While you have it apart why not replace all the studs to prevent anymore leaks.
They break off due to hot corrosion and cyclic loading hot cold hot cold.
You should be able to retap the hole if it is stripped if you can't you may need to helicoil it or drive a larger bolt in there bearing in mind it has to be heat rated. You should be able to pull the head with the manifold but i have never tried on mine. don't know why not

hth
 
pull the head with the manifolds on , actually mafes it easier to handle as you have somewhere to grip as that head is pretty heavy . Do yourself a favor and replace ALL exhaust studs and intake studs with new ones . Also replace all nuts and lock washers with new . When I did my head I replaced all and it only cost $50 cdn. for the hardware from UAP NAPA . You don't have to worry about a stud snapping off when you are torquing to spec. Yuo said you wanted todo the job right , then this is one of the steps .
If you you can't get a stud out or nut off here is a trick I have used in the past that works ( if you don't have oxy torch). Drill a 3/32 hole through center of stud all the way through , stick the penetrant straw in there and fill her up let soak for a few hours or better yet over night and it usually comes right out . Saves the trouble of having to heli-coil or taking it to a machine shop .
HTH Daryl
 
once the head is sitting on the bench then yyou should be able to use a reverse drill bit and that bugger will just turn right out...
BTW, wicked idea about drilling a hole and squirting the fluid into the bottom. i never thought of that one...
i would suggest do NOT use and easy out. i have had nothing but terrible luck with them. a gent suggested the reverse drill bits on another list and after buying a set of them, life got much easier...
cheers
 
Jesus Wayne , don't you sleep ?it is like 6:30 am there ! I have used easy outs a couple of times in my early years but they are to damn easy to Fudge up and when they break off in there you are totally fudged , I do not use them any more and do not suggest them either . I have spent hours up on hours trying to chip out broken off easyouts that apprentices have broken off . This is in parts on aircraft so it gets really expensive ! The reverse bits work great also .
If you are real steady and the 2 suggestions don't work here is another one that has saved my ass a few times . Step drill up slowly to almst the size of the tap clearance size , then take a GOOD sharpe small pin punch and chip the remaining threads from the stud or bolt away . reach in with needle nose and pull it right out . has saved my ass when all else fails.
HTH Daryl
 
Daryl, the step up size is what i do with the reverse bits usually all at once it grabs and the whole broken bit just turns right out. it seems to work quite good. my hand is nowhere near steady enough to try drilling that close to the treads but worse case he could drill the stud out completely and go one size bigger...
i think he will find the exhaust studs are going to come out quite easy once it is on the bench...
on bolts that have nothing behind them i just use regular bit and drill the bolt, usually they catch and walk right out the back, rmove from drill bit and you are good to go...
we are up at 5:30 every morning except sunday... then it is "spend time with my wife watching Cornation Street" once you allow yourself to get into the show it gets quite addictive.
(there goes my tough guy image)
;^)
cheers
 
Pull the head mostly assembled, put it on the bench and use some head on the fasteners if they are stubern.

My favourite tool is my impact on a low setting, the hammering effect almost always works. If it does not I use a little more heat.

Almost always the impact does the job.

My choice is the titanium IR gun.

Rob
 
Guys,

Thanks for the great suggestions. I will pull the head with both manifolds on and work on the bench.
Another couple of questions and probably a couple later on.
1. Is there anything special, like caution, removing two clear hoses from intake?
2. Do I have to remove the fuel hose from the filter assembly or just kind of move out the way?
3. After removing the injector pipes, what is the best thing to cover the injection pump to make sure that dirt will not be introduced into the pump?

Thanks,
Alex
 
Thanks for the great suggestions. I will pull the head with both manifolds on and work on the bench.
Another couple of questions and probably a couple later on.
1. Is there anything special, like caution, removing two clear hoses from intake?
--- go for it
2. Do I have to remove the fuel hose from the filter assembly or just kind of move out the way?
---either / or i usually just move it out of the way
3. After removing the injector pipes, what is the best thing to cover the injection pump to make sure that dirt will not be introduced into the pump?
--- shop rag
 
Guys,

A friend of mine came over to help me to pull the head. To my surprise I didn't find any visible cracks between the valves, but the are some small cracks in pre-cups. What do you recommend, replace them or just leave them alone. Another thing that I found was some metal shaving near the water jacket between 3rd and 4th cylinders. My guess is that from warn exhaust rockers. I will post the pictures of precups tomorrow. Head gasket looked ok.

What is the best way to cover the water jackest while cleaning the remains of the head gasket?

Thanks,
Alex
 
Live from moab slickrock campground.. good to hear things are better than planned alex.

On a side note, we ran Hell's revenge today and the BJ performed flawlessly :)
 
Wes,

You should have 8 pounds of Gibbles some time next week. Enjoy them when you return from Moab!!

Alex
 
bj70alex said:
What is the best way to cover the water jackest while cleaning the remains of the head gasket?

Thanks,
Alex
Click to expand...

Just flush it a bunch when you get it back together. Its impossible not to get some crap in the water jackets. I find that those cheap rollup foam earplugs work really well at pluging holes other than ear canals.
 
Well, I was going to take some pictures from precups, but I don't think its worth doing it. All 4 precups have cracks in them. So I guess I have to replace them.

Guys, where is best source for them? Dealer is about $100.00 each, not sure about 4wheelauto. I tried to access there website and for some reason, doesn't work. I think someone mention th eprice of $25.00 each.

Thanks,
Alex
 
lowenbrau said:
If you can get them for $100 ea at the dealer, go for it. Last I heard they were 4x that.

4 wheel auto is $99 each.

http://store.4wheelauto.com/view_product.php?product=PRED0LAS22
Click to expand...

I sell the stainless cups for about 40.00each or around 32.00 US, good quality. I even have the injector crush washers, most shops will give you the washers when they reman your injectors.

When your into the engine that deep, recommend changing out the water pump (unless recently doen) replacing rad hoses.

Does everyone here adhear to the fsm when removing a head and loosen the bolts in the opposite fashion to torquing them down?
 
i always untorque all heads opposite to the tightening sequence. Just makes sense. Never really thought about it!!!
 
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