Disappearing Coolant?

[Ecomike]

To non-OP poster, ihscoutlover:

Anything under 120-125 PSI is too low and needs repairs. The MAX allowed delta P, between two adjacent cylinders is 20 PSI!!!

VERY, very hard to believe a jeep can get 18 MPG with those super low compression numbers, 90-115, WOW!!! New 4.0 is about 170 PSI, IIRC, 160-170 is normal on a new engine!!!

You might retest with the wet method, add a teaspoon of oil into the spark plug hole first, then retest. If they are still that low, you have serious engine problems, and it is hard to enough get combustion that low, with out frequent missfires.

Sounds like some serious coolant leaks (head cracks) into the combustion chambers.

 

[Ecomike]

Well i just bit the bullet. Bought a head for $500. Gaskets are going to be like $100. Head Bolts were $40. $50 for the test on my old head.

About $700 later my jeep should be back to running condition. Could be worse i know, but my god, i did not want to spend any money. I'm trying to save as much as i can. Hoping the jeep is more reliable after this.

I had the same symptoms. My oil fill cap was milkshaked, then about two weeks later i pulled the valve cover, and that too was milkshaked. Oil level seemed fine as well, no lack of performance, and my temperature was lower than 210. Spark plugs looked fine as well.

I even had the 0630 head, and it still cracked.

I'm curious. Where are you guys traveling to?

I have a question. I've never replaced a headgasket in my life. Do i apply the headgasket dry, or do i add RTV around all of it, or do i put on a few dabs of RTV around the outside of it to hold it onto the head or what?

After reading that tip about using old bolt heads with cut off heads and slots in them, i was thinking i should just drop the headgasket over those bolts dry, and then drop my head down on top of that. No RTV or anything. Is that correct? Or do i need RTV?

What about the intake manifold and the exhaust manifold? Those installed dry as well?

Thanks!

Do not use RTV on the head gasket! Either paint it with a light thin coat of aluminum paint, or use Indian head gasket shellack compound.

Use the Copper RTV on the front driver's side head bolt that goes into the coolant chamber on the head. The one that gets the reduced torque spec. Then coat both sides of the intake-exhaust manifold gasket (intake-exhaust is one gasket), with a thin coat of the copper RTV as well.

BUT, check the exhaust manifold for cracks at the welds before you install it, and check it flatness. Use a long metal ruler edge.

Clean out all the bolt holes with solvent and later a shop vac (after it dries). I used 90% IPA alcohol and Q-tips for the final cleaning step.

Seriously consider using new exhaust manifold bolts and nuts if they are rusted badly!!

 

[ihscoutlover]

To non-OP poster, ihscoutlover:

Anything under 120-125 PSI is too low and needs repairs. The MAX allowed delta P, between two adjacent cylinders is 20 PSI!!!

VERY, very hard to believe a jeep can get 18 MPG with those super low compression numbers, 90-115, WOW!!! New 4.0 is about 170 PSI, IIRC, 160-170 is normal on a new engine!!!

You might retest with the wet method, add a teaspoon of oil into the spark plug hole first, then retest. If they are still that low, you have serious engine problems, and it is hard to enough get combustion that low, with out frequent missfires.

Sounds like some serious coolant leaks (head cracks) into the combustion chambers.

Thanks Mike. The Haynes manual calls for 125 per cylinder. He's running everything to check and rule it out. I averaged 17mpg from Louisville back to stl running 70mph. I scanned it for codes last night and none. If had a recurring O2 sensor one but it hasn't been back for almost 1k miles but no misfires so far. It's probably way non-efficien right now but with the repairs I should be back in business again.

Jeff

 

[joe_peters]

1. Your (anyone's) oil filler cap can look that bad or worse from NORMAL condensation in the crankcase IF the CCV system is not operating properly and you make a lot of "cold start short trips". If the engine doesn't reach normal operating temperature for a long enough time the oil will not be heated to the point of burning off the naturally occurring moisture in the crankcase.

2. However, you can have disappearing coolant without coolant getting into the crankcase--it can be going out the exhaust. With the angle of the picture of your spark plugs I can't tell if any have been "steam cleaned" by a bad headgasket. Try posting up a photo with a head on angle of the electrode end of the plugs. That said, the second from the right and the third from the left appear pretty clean.

 

[Kingkong0192]

Alright my last group of questions (or so i think) before i replace my head. I'll probably come up with some more that need answering when i begin putting it all back together.

So to put the head back on i first need to clean the block off (where the headgasket goes.) What's the best way to do this? I'm pretty sure i want to avoid an angle grinder with a wire wheel. What are those things called that are like plastic fingers that you put in a right angle die grinder? Would one of those work to clean off old gaskets? How do you normally clean off gaskets? As i said earlier, this is my first time.

Anyways, once i get the old gasket off, you're telling me to take a thin layer of either aluminum paint or indian head gasket shellack compound and paint it over the headgasket it self on both sides? Then drop the headgasket over the old head bolts that have been modified to help line up the head?

But before this, i take my exhaust-intake gasket and paint that on both sides with a thin layer of Copper RTV and bolt that to the new head because it's easier to do it in this order. Correct?

My exhaust manifold was cracked. I welded it in the area of the crack and fixed that. Then take a long metal ruler and check to make sure the exhaust manifold is flat.

What bolt holes do i clean out? My bolts weren't rusted at all. Would you reccomend using anti-seize on them or just running them back in dry?

Once i drop the head on, i proceed to torque down the head bolts in stages (i have the stages already saved - just not going to type them out.) then i simply proceed to put everything back together, correct?

Am i missing anything? Want to make sure i do this correct and don't have to go back and re-do anything later for a flaw now.

 

[Ecomike]

Alright my last group of questions (or so i think) before i replace my head. I'll probably come up with some more that need answering when i begin putting it all back together.

So to put the head back on i first need to clean the block off (where the headgasket goes.) What's the best way to do this? I'm pretty sure i want to avoid an angle grinder with a wire wheel. What are those things called that are like plastic fingers that you put in a right angle die grinder? Would one of those work to clean off old gaskets? How do you normally clean off gaskets? As i said earlier, this is my first time.

I just use a carpenter's putty knife-scrapper.

Anyways, once i get the old gasket off, you're telling me to take a thin layer of either aluminum paint or indian head gasket shellack compound and paint it over the headgasket it self on both sides? Then drop the headgasket over the old head bolts that have been modified to help line up the head?

Yes, but you do not take a thin layer, you make a thin layer, paint a thin layer on.

But before this, i take my exhaust-intake gasket and paint that on both sides with a thin layer of Copper RTV and bolt that to the new head because it's easier to do it in this order. Correct?

That is how I did it. It was heavy as hell, and took me, my son and daughter on three sides levitate it (LOL). Others say it is not that hard to install the bottom manifold bolts last, I disagree. Take your pick!!

My exhaust manifold was cracked. I welded it in the area of the crack and fixed that. Then take a long metal ruler and check to make sure the exhaust manifold is flat.

If the Exh manifold is not flat, if it warped from the weld repair, it will leak!!!!! It needs to be flat!!!

What bolt holes do i clean out? My bolts weren't rusted at all. Would you reccomend using anti-seize on them or just running them back in dry?

Clean all the bolt holes. I did not use antisieze as it changes the torque spec on the bolts!!!!

Once i drop the head on, i proceed to torque down the head bolts in stages (i have the stages already saved - just not going to type them out.) then i simply proceed to put everything back together, correct?

Am i missing anything? Want to make sure i do this correct and don't have to go back and re-do anything later for a flaw now.

Sounds good to me.

 

[heyhar]

Take a look into all the coolant passages. I had the head off my '92 years ago, and the passages were rather coked up with coolant residue. It never overheated before, but it ran cooler afterward. Your 'new' head should be nice and clean, so concentrate on the block, and hopefully you'll have a cool ride!

 

[ihscoutlover]

Well King Kong, my XJs diagnosis is in. No external leaks found. All evidence points to a head gasket or head. I am rounding up the parts today through this weekend. Head is gonna set me back the most, but is available locally. All other parts are going to cost wholesale so parts should be less than $1k. Now to enlist help from the local jeep clubs. I will be starting a thread on this to show my progression day by day.

Jeff

 

[Ecomike]

`1K????????????????:wow:

I bought two jeeps for that much!!!! OUCHI!

 

[ihscoutlover]

Mike the head from Alabama cylinder head/coldwater cylinder head was $455. Parts like head gasket set and bolts and other misc stuff is probably another $300. I am just fixing it so we have another reliable DD jeep. True I've bought two Scouts for under $1k before too, but if I do it right once I won't have to do it ever again. Besides if I've done it once ill be more confident doing it again...if I have to and the price is reasonable.

Jeff

 

[Ecomike]

Mike the head from Alabama cylinder head/coldwater cylinder head was $455. Parts like head gasket set and bolts and other misc stuff is probably another $300. I am just fixing it so we have another reliable DD jeep. True I've bought two Scouts for under $1k before too, but if I do it right once I won't have to do it ever again. Besides if I've done it once ill be more confident doing it again...if I have to and the price is reasonable.

Jeff

Head gasket kit is only $50 IIRC, just the gasket may be less (mine included valve stem seals), and about $45 for the head bolts, few dollars for the other goodies. Unless you plan on replacing a bunch of stuff, maybe $125 plus the head.

 

[Kingkong0192]

Mike the head from Alabama cylinder head/coldwater cylinder head was $455. Parts like head gasket set and bolts and other misc stuff is probably another $300. I am just fixing it so we have another reliable DD jeep. True I've bought two Scouts for under $1k before too, but if I do it right once I won't have to do it ever again. Besides if I've done it once ill be more confident doing it again...if I have to and the price is reasonable.

Jeff

Do you know about the advance auto discount codes? If you have a local advance auto and you buy the parts online you can get like 25% off and save yourself a good chunk of change.

Just buy as much as you can from advance auto, because the more you spend the more you're going to save.

I'm going to buy the kit from them that has all three of the gaskets (head, exhaust and valve) it's like $130. I should be able to get it for around $90 with codes. Then i'm going to need some copper RTV and some other stuff. Head bolts were like $38 shipped. You shouldn't be spending anywhere near $300 for misc stuff. Closer to like $150-175.

Here's the link to the discounts from advance auto. I just keep using codes until i find one that saves me the most. I normally either use "M20" or "A124" though. They seem to work the best.

http://www.jeepforum.com/forum/f13/advance-auto-discount-codes-1327649/

 

[ihscoutlover]

Well I'm privvy to the fel-pro gaskets. Mine was $100. It is the whole set. It includes the expensive reusable rubber valve cover gasket. Most of the parts stores carry that one for almost $150. I saved $50 just there. I have the factory heater hoses to replace, spark plugs, a replacement temp sender that I broke during water pump replacement, the tensioning pulley, head bolts which were $23/change. Basically I spent $240 on the parts. Ordered the head from Clearwater which was $455 shipped. I figure I'm gonna have $700 in the parts when I'm done. Considering the labor at one shop for R&I of my head was $1100, I'll spend the money on the parts and save the labor dough for some buddies to help get it done, ones that have already done this before. This way I can feel pretty confident that I've got all my bases covered. Mike I have no idea where you got that whole head set for $50, but it must have gone up since you bought it, or the parts suppliers want us to pay since they know we will need to do the repair. I'm happy.

Jeff

 

[Kingkong0192]

I just bought all my gaskets as well. My total to fix everything is;

$568.61. Probably going to be closer to $600 even as i forgot to buy new coolant, and i need to buy another heater core hose (i accidentally cut mine.)

Another question i just thought up;

How do i install the push rods and rockers again? The lifters will all be in different positions, and won't some of the valves have to be open? Do i need to get each piston to the very bottom of the cylinder when i put the push rods and then rockers back on?

Or am i over-thinking this?

 

[heyhar]

Nah, not over-thinking. What I like to do is liberally drizzle some oil into the lifters, slide all the pushrods down into the lifters, set the rockers and the bridges on their studs, and run the nuts down close to the final spot, just don't tighten them down yet. Give 'em a good dose of oil! Start with #1, just because, and rotate the crank to TDC, on the firing stroke, and you'll know that both valves should be closed. What I've done is then tighten the nut down till the rocker barely has a load on it, maybe a hair loose, as the lifter will fill with more oil, pump up, and take the rest of the slack. Repeat this for all six cylinders, and you'll be close. After the engine is started, and it comes up to temp, you can tighten away a loose or tapping rocker, taking care not to over-do it, because if a rocker is too tight, it may not allow its valve to close completely. Hydraulic tappets take the guesswork out of valve adjustment. Somewhere between loose and tapping, and too tight and a valve not closing, you'll find the sweet spot. Good luck, and keep us informed of the ensuing madness!

 

[Kingkong0192]

Alright that makes sense.

I just cleaned off the head, and made those old head bolt studs to help align the new head when it comes it and screwed them into the block. (through the method ecomike explained.)

My other question(s) are this;

1. I noticed in the oil passes on the driver side of the block if i spray compressed air down there and move the mixture around i can see green in there. Obviously from the cracked head leaking coolant down. Is there any way to clean this out? I mean, i can't think of a vacuum cleaner or something like that to do it.

2. Is there any method to "Break in" the new head? Should i run like marvel mystery oil through it (i think that's what it's called) or should i do an oil change every 500 miles or so for the first 3,000 miles, or something like that?

I think that's about everything i need to know, and i should have the jeep back together. Unless anyone else has any tips.

I can't thank you guys enough.

 

[ihscoutlover]

Use a wet/dry shop vac, if you are wanting the fluid out of the jackets so that there isn't any oil and coolant mixed. Or what I would do is just run the engine after you get it all back together and can get it up to operating temps, then shut it down and change the oil. I am going to change mine, as it not only has 4k on this last change, my plan is to redo the exact composition of Lucas and Rotella that I had in there before.

Jeff

 

[Kingkong0192]

Use a wet/dry shop vac, if you are wanting the fluid out of the jackets so that there isn't any oil and coolant mixed. Or what I would do is just run the engine after you get it all back together and can get it up to operating temps, then shut it down and change the oil. I am going to change mine, as it not only has 4k on this last change, my plan is to redo the exact composition of Lucas and Rotella that I had in there before.

Jeff

Ill run some cheap oil through it for like 200 miles, then i'll change out the oil and filter again. Should be good to go from there. Vacuumed out the coolant/oil with some success.

My last question as my head should be in tomorrow.

Ecomike said i should apple Indian Head Shellack Compound to my headgasket.

Do i literally paint both sides of the head-gasket with this stuff with like a nice thick layer of it, or do i just lightly brush it onto both sides? Do i paint the head and block with it as well, or just paint the gasket?

I'd hate to have the headgasket leak on me.

 

[Ecomike]

Thin layer only, on both sides of the gasket only. Do not use it on the head or block, they should be clean and dry.

Get the coating as thin and flat as possible, let it dry on one side, then do the other side. I think it helps water proof and seal the gasket. Some people just spray paint the gasket with an aerosol can of aluminum paint.

You might try a thin long paper towel, and long screw driver to reach in and soak up any coolant in the deep recesses. Might also look on line for a water absorbing spin on oil filter, to swap ever hour of running time the first couple hours? As they remove water the back pressure climbs, so just watch the dash oil pressure for when to replace it.

 

[Kingkong0192]

I have another question. My head still has NOT arrived. It's been over two weeks, and needless to say for $500 i think they should of had the thing in already.

I'm going to cancel the order tomorrow, and get my $50 deposit back. That's ridiculous.

I found this entire 4.0 engine from a 1998 Wrangler. Guy wants $125 for the cylinder head. Says it has over 100,000 miles on it. Is this compatible, and would you guys go for it, or would you get a head from somewhere else?

Link is the craigslist ad;

http://nwct.craigslist.org/pts/3672070906.html