Head Gasket issue inquiry

[Seiler]

Hey guys,

Firstly, info: '97 XJ with ~140k AW4

I'm starting to suspect my head gasket is causing some problems. I'm burning/leaking coolant from somewhere. I can see a buildup of anti-freeze if I lay under the jeep, and look up towards the exhaust manifold. It almost looks like it's leaking out the exhaust ports onto the bottom of the manifold. From what I understand, there's no place for it to leak out at that location, besides the head gasket.

What's puzzling me, is the lack of blown head gasket symptoms I don't seem to be encountering. It doesn't feel like I have a loss of power, no white smoke from the engine bay or exhaust, it doesn't overheat, and it runs fine. Last time I changed my oil there was no milkshake like appearance, and there's no oil buildup in the cooling system.

Besides the visible buildup of anti-freeze I found, once the engine warms up and the thermostat opens, there is a STRONG, profound smell of maple syrup coming from under the hood.

By any chance, does anyone have any advice? Or, would anyone be willing to loan a compression tester out for a few hours while I try to figure this one out?

Thanks,

Scott

 

[YELLAHEEP]

Check your freeze plugs. Look for rust/rot, green/white crusty stuff, and drip trails down the block from around the plugs. If they're rusty/rotten, they may have a pinhole leak that's spraying onto the manifolds.

Could also be just the outter part of the head gasket leaking - not into the cylinders, but from the water jacket out between the block and head. Again, corrosion of the head gasket may have allowed some leaking out that way. It also will mist/spray out and could be spraying onto the manifolds...... and it won't cause those symptoms you're describing because the coolant isn't getting into the oil or cylinders.

Should be a fairly visible white/green crust built up from where it's leaking from no matter where it's leaking, but given that the manifold side of the engine is obviously the hotter side, it may be vaporizing the moisture quicker than other locations around the engine.

 

[Seiler]

Checked the freeze plugs. They all look fine. No visible leakage signs. (the ones I could get to anyway, excluding the 2 that are not on the side of the block) I also checked the water pump, in thinking it might have run towards the rear while the vehicle is moving if it was leaking. Nothing.

The leak I have is above the freeze plugs, way above. Looking down from the top of the motor, I can't see anything. But, when I look up from the bottom of the motor, I can see a moist, wet to the touch buildup right at the base of the exhaust manifold. I tried to take a snapshot, but that was practically impossible. I couldn't get enough light up to illuminate the spot. In relation to a "white/green crust build up," It's all wet. Nothing appears to be dried up enough to display that particular characteristic.

Scott

 

[YELLAHEEP]

Yep, sounds like a seeping head gasket. There isn't much distance between the bottom of the head surface and the exhaust manifold flanges so I'm betting that's the issue.

You can see the small triangular chambers of the water jacket between the cylinder and the exhaust manifold.... there's maybe 3/16" to 1/4" of gasket that seals those water jacket chambers.

If I were you in this situation, I'd check the torque on the head bolts with the engine cold. Check all of them to ensure you have good even torque. To do that, you'll have to remove the valve cover to get at all of 'em.

If you get any of those head bolts to turn on the manifold side of the head, you may be lucky and get it to seal. Otherwise, yeah, it's gonna need a new head gasket. Not the easiest job, but not the worst.

If you have to do the head gasket, make it simple by leaving the intake/exhaust on the head. Use an engine hoist and chain to lift the head straight up when you have it apart. Clean both surfaces real good, then replace the head gasket and lower the head using the engine hoist. A second set of hands would be ideal.....

 

[xj-grin]

Yep, sounds like a seeping head gasket. There isn't much distance between the bottom of the head surface and the exhaust manifold flanges so I'm betting that's the issue.

You can see the small triangular chambers of the water jacket between the cylinder and the exhaust manifold.... there's maybe 3/16" to 1/4" of gasket that seals those water jacket chambers.

If I were you in this situation, I'd check the torque on the head bolts with the engine cold. Check all of them to ensure you have good even torque. To do that, you'll have to remove the valve cover to get at all of 'em.

If you get any of those head bolts to turn on the manifold side of the head, you may be lucky and get it to seal. Otherwise, yeah, it's gonna need a new head gasket. Not the easiest job, but not the worst.

If you have to do the head gasket, make it simple by leaving the intake/exhaust on the head. Use an engine hoist and chain to lift the head straight up when you have it apart. Clean both surfaces real good, then replace the head gasket and lower the head using the engine hoist. A second set of hands would be ideal.....

What Yella said -- I'm becoming a head gasket pro, if you want to do it in the springs, and if I could manage to make garage space for ya :tears: Plus, I currently have FrankZ's hoist, so I can do the above pictured manuver and avoid taking off all the intake/exhaust - Highly recommended. Oh, and buy the more expensive HD Felpro head gasket, black with blue ridges, not blue with red -- get them side by side and you'll see the difference in quality. eace:

 

[Seiler]

Thank you for your offer xj-grin! I might have to take you up on that if I can find a way to get it down to you. Not to mention, I'm somewhat inexperienced when it comes to engine work. I think it would make me more comfortable tackling this with someone who has done it before. :thumbup: I'm not sure I feel comfortable driving the rig down there if it's something to be concerned about. I shall get back to you if I figure something out. I really appreciate it. Does a hesco head gasket lean towards the better quality spectrum? They sell a single layer as well as a multi-layer gasket on their website.

In a situation like this, isn't it necessary to have the head machined, maybe a valve job as well? Back when I had my Eclipse, I had considered replacing the head gasket. Part of the recommended procedure always included getting the head machined.

Thanks for your replies,

Scott

 

[xj-grin]

LOL - Scott, you probably aren't aware, but my XJ has been stuck in my garage for the better part of 5 months having stroker surgery. I'll be putting the 3rd head gasket on it this week sometime, having disassembled/rebuilt/reassembled/disassembled/reassembled... searching for a valvetrain problem post rebuild. IF I can get it fixed this week, I'd be happy to help out.

That said, you likely should have your head checked for warpage - it could be you've had an overheating issue you weren't aware of and warped your head, which would lead to the symptoms you're experiencing. Better to have it checked and do it once than to throw a new gasket on and find out you didn't fix the problem. If you knew it was a gasket, driving down here likely wouldn't be a big deals since you indicated you've had no indications of coolant consumption in the engine - but, no offense, I really don't want your rig in my garage for the 2 weeks it might take my machine shop to getting around to checking your head! (you probably don't want to either).

Like I said, happy to help, but you'd best get the head checked in the process.eace:

 

[Seiler]

LOL - Scott, you probably aren't aware, but my XJ has been stuck in my garage for the better part of 5 months having stroker surgery. I'll be putting the 3rd head gasket on it this week sometime, having disassembled/rebuilt/reassembled/disassembled/reassembled... searching for a valvetrain problem post rebuild. IF I can get it fixed this week, I'd be happy to help out.

That said, you likely should have your head checked for warpage - it could be you've had an overheating issue you weren't aware of and warped your head, which would lead to the symptoms you're experiencing. Better to have it checked and do it once than to throw a new gasket on and find out you didn't fix the problem. If you knew it was a gasket, driving down here likely wouldn't be a big deals since you indicated you've had no indications of coolant consumption in the engine - but, no offense, I really don't want your rig in my garage for the 2 weeks it might take my machine shop to getting around to checking your head! (you probably don't want to either).

Like I said, happy to help, but you'd best get the head checked in the process.eace:

I had a feeling you were being slightly sarcastic. I thought maybe a little thrown back at ya wouldn't hurt? I'm familiar your stroker thread, and giggled at your garage space comment.

Think any ol' machine shop will do, or should I look for one that specifies in auto machining? Like I said, new to all this. :eye:

S

 

[xj-grin]

I had a feeling you were being slightly sarcastic. I thought maybe a little thrown back at ya wouldn't hurt? I'm familiar your stroker thread, and giggled at your garage space comment.

Think any ol' machine shop will do, or should I look for one that specifies in auto machining? Like I said, new to all this. :eye:

S

I bet one of the brethren will chime in with a good machine shop referral for the Aurora area, yes Automotive machining. Once you know you have a good head, if you can turn a wrench, you can swap a head gasket, its just alot of accessories and such to remove.

 

[old_man]

I highly recommend spraying the head gasket with CopperKote before assembling the head. I've been using it for 40 years and it really helps.

 

[xj-grin]

I highly recommend spraying the head gasket with CopperKote before assembling the head. I've been using it for 40 years and it really helps.

I agree, I've always used the spray permatex copper stuff too...

 

[JJacobs]

That would probably be ok even though the gasket kits say 'use no sealer'. Reason being it's an iron head, iron block engine. In an aluminum head, iron block engine that'd cause problems as the gasket continually scuffs sideways between the two metals.

 

[xj-grin]

I always liked the inconsistency of the gasket instructions saying "use no sealant" and the manuals (Haynes, Chiltons, FSM) saying "use permatex or equivalant on both sides"... :wierd:

 

[JJacobs]

Haynes and Chiltons don't count as manuals. I think they reconstitute 1973 Maverick information in all their books with just enough real info added in to confuse people. The FSM is tailored for factory parts- and what you got from Felpro probably isn't.

 

[Hypoid]

I tend to heed the information provided with the gaskets. After all, they made the stuff, they should know what works with it.

 

[YELLAHEEP]

From personal experience - as JJacobs is as well - I'll second the no permatex/copper coat on aluminum heads, but definitely use the copper coat on iron heads. :thumbup:

 

[xj-grin]

one of you Denver-ish dudes should recommend a machine shop for Scott to have his head checked...























































(yes, innuendo intended...):cheers: