Jeep Nathan and Tanja's 99 XJ Build up

[thenag]

Well Clegg says the head is reparable!

He said it was only slightly warped and could be milled flat, but since it was warped it did overheat. I didn't get a chance to ask him too many questions, the good news was that I don't need a new cylinder head.

I should have it back next week, depending on how many other parts I end up replacing the jeep should be back together for a fall leaf run.

Nathan

 

[thenag]

Ok so Clegg said that the main reason the motor failed was that it over heated. Other things may have contributed but the only reason a motor fails with less than 10,000 miles with a warped head is that it over heated.

I have had 3 times that a radiator hose has come off including the time that had a stuck valve. It is possible that I lost coolant and then the valve stuck. I have convinced myself that over heating is the main issue.

I already have the super duper Mishimoto Radiator and a Flow cooler pump, I also have a small hood vent and have removed the weather strip at the rear of the hood.

I am going to do a few things to help;
add a wetting agent to the coolant and run my coolant 60% water 40% coolant, I am going to run prestone, that Mishimotto Synthetic may have been an issue.
install a "high flow" thermostat housing
I found an AC Delco "high flow" thermostat, although it looks like what I had in there it claims to be "high flow"
Install another tempurature gauge
always have at least 2 gallons of water or coolant in the back.
New radiator hoses (again)
I am going to remove my Ford oil to coolant cooler. (ford guys remove them because they end up having problems with them leaking coolant into oil, I installed it because my exhaust ran too close to my oil pan, the exhaust is much different now so the oil cooler is probably not required)
I am going to move my crank position sensor slightly more toward the OEM location. I am at 5 degrees advance, I want to be at 3 degrees. I don't know really know why I am doing this one.
Install the spark plug that Clegg recommends (Autolite 3924)

I have always felt that something wasn't quite right with my stroker, maybe the head gasket didn't quite seal right or something, so I do have a hope that when I put it together it will just run better and cooler...

Anyway here are some pictures.

Bent exhaust valve


head ready to be installed


The head gasket they sold me is a MLS (multi layer steel)... bling bling right


A box from Summit Racing came in, Redline Water Wetter


This is the temp gauge I ordered from Summit, it is like a digital alarm clock LCD, it is white. Still not sure where it is going in the cab


The 7120 head that I have has a port for a temp sensor on the back of the head


The head dropped down really easy, I did have to do it twice since I forgot to install the back head bolt in the head before placing it on the block. (uni-body prevents dropping the bolt in after the head is in place, I knew this and still forgot...)


Rocker arms installed and moving properly, it took me longer than it should of to realize why it was so hard to crank the engine by hand... had to shift into neutral...


Valve cover back on, so the engine is really back together. You can see the melted motor mount that needs to be replaced and I am going to build a little heat shield for it. It is probable that it melted when I was driving with a stuck exhaust valve, that would put combustion into the header and super heat the header, but a heat shield won't hurt. The 2000,2001 xj's have a heat shield from the factory. BTW if anyone has one of those heat shields laying around let me know I will give you a few bucks for it.


I should have it mostly together this weekend. My "high flow thermostat housing" doesn't come in until next week so it won't be running this weekend.

 

[gatchmo5710]

Id look into your timing advance for the reason heat build up....not the cooling system. You might have to compromise between power and heat management unfortunately.

 

[mbryson]

Still running OEM fan setup?

 

[thenag]

Id look into your timing advance for the reason heat build up....not the cooling system. You might have to compromise between power and heat management unfortunately.

Yeah when I modified my crank position sensor I wanted it to be adjustable, it wasn't it was 5 degrees, I have now made it with a little adjustment in it, I brought it back a bit. It is really a guessing game with a timing light it doesn't stay right on the mark like timing my old bronco. I would have to put an OEM sensor back in get a good feel for where the timing is, then put the modified CPS in and play around with it. With the lack of accesability of the CPS I doubt I will mess with it.

Still running OEM fan setup?

Yes, and I don't know that there is a better option, other than solid spacer on the mechanical fan. I am not convinced that the 3, 10 inch electric fan setup will actually move more air than the OEM setup. It certainly depends on using really good fans. I could mix fans with different CFM's and of course with and aftermarket fan controller I could have one fan run for a minute after shutdown which would help with the "heat soak" issue. On so many of the forums a lot of guys switch back to the OEM setup after trying the 3, electric fans. Also the Dirtbound electric fan shroud doesn't look that sturdy.

Nathan

 

[thenag]

Pretty much everything is together except the parts I am waiting on, and the paint to dry on the spacer for the new temp gauge.

speaking of the new temperature gauge...


Here is the melted Motor mount, I have decided that this had nothing to do with the stuck valve. The stuck valve was #5, #5 exhaust doesn't go anywhere near this mount... #1 however...





New bushing installed.



My new little heat shield



And how close the header runs to the motor mount



You would think that it would be easy to get to the crank position sensor like this, you would be wrong...



This is my modified crank position sensor, I removed the the allen bolt and it all stayed together, so without the the allen bolt in the hole the sensor is allowed to slide on the slotted holes a little, I moved it back toward TDC.


This header is really really hard to install with the engine in the jeep. In this picture you can see 4 ratcheting box wrenches on the 4 nearly impossible bolts to get to. Those 4 bolts are shared with the intake, so after this picture I slide the intake on and then somehow become double jointed on all my fingers to actually tighten the bolts. I made it extra hard by having the exhaust installed too. I always laugh that the FSM expects you to torque the bolts to exactly 24 ft/lbs.



After work tomorrow I should be able to put the dash back together.

My "high flow thermostat housing" should arrive on Tuesday.

Nathan

 

[mbryson]

I’ve had good luck with the XJ stock cooling system as well

 

[Jay5.9L]

Would it help getting the headers ceramic coated?

 

[thenag]

I did get this running again, everything seems fine except I can't seem to get all the air out of the cooling system. You come across forums of people with issues getting the air out of an xj so I guess it is my turn. I haven't had issues in the past. Fill up the radiator, start the engine, top off the radiator, put the cap on fill up the expansion reservoir, heat up the engine a few times keep the reservoir topped off, repeat until reservoir is at the same level when cool. I think it is now drawing coolant from the reservoir so fingers crossed.

I even bought a "spill free funnel" which still didn't burp all the air out.

Until I get the air out I can't really comment on if I think the Water Wetter is working.

A few observations;
The OEM temp gauge is an idiot gauge (we all knew this but to have an actual gauge to watch opens your eyes to how stupid it is) For example my fancy new guage will say 210, the dash gauge is straight up at 210. Cool. My new guage says 220... the dash gauge is a needle width above 210.. so the dash says 212-215ish... My new gauge says 230 (quick turn the heater on!) the dash gauge is barley above 210... Not cool. I have a bluetooth OBDII scanner and looking at the water temp that the PCM is reporting to the OBDII app the OBDII app temp is almost identical to the new gauge. Which I find really interesting since the new guage sensors is on the back of the head and the OEM sensor is in the thermostat housing. So if you feel like you need to monitor your temp and have an OBDII scanner just use that.

It is pretty cool watching the temp come up to about 200 then watching it drop quickly back to about 180 when the thermostat opens. (this is on initial warm up when the coolant is still pretty cool)

Also don't buy a Hesco "high flow" thermostat housing, it is visually identical to the OEM one. I didn't mesure anything but there is not any difference in it. (there is a small chance that the one I had on there was a Hesco that I forgot I bought so I might be comparing Hesco to Hesco but I don't think so)

lets see some pictures...

OEM and Hesco


Fancy spill-free funnel


spill free funnel in action


How I really made my upper radiator hose lower than the funnel... un-hook swaybar, open tire carrier, let air out of tires, put hi-lift on rock slider. This still did not get all the air out of the system


Shot of gauge

 

[thenag]

Would it help getting the headers ceramic coated?

Probably.

I could coat the header and the first part of the exhaust pipe too.

 

[thenag]

I have been able to get the cooling system to draw a little coolant from the reservoir, It only seems to work if I get the engine up over 220 degrees, then it only sucks a little bit in.

In the past the first couple of warm ups it would only suck down a little coolant, then it would suck down quite a bit and then it would stay the same level when it was cool. (the coolant in the reservoir would rise when warm then return to the same spot when cool)

I am thinking that I am having issues purging the air out because of the water wetter.

It seems to be purging out so hopefully it will work the rest of the air out.

Nathan

 

[Jay5.9L]

Not sure why water wetter would make a difference in the purge. I've used it and more recently purple ice and it seems to act the same in general .

 

[gatchmo5710]

Id offer you my vacuum coolant filler from snap on but im down in hurricane ut. Might wanna see if someone near you has one. They work amazing.

 

[thenag]

Id offer you my vacuum coolant filler from snap on but im down in hurricane ut. Might wanna see if someone near you has one. They work amazing.

If I am still having issues by the end of the weekend I might have to order one, It looks like the mighty vac is pretty similar. I wonder if the small radiator cap in my Mishimoto will be still work with that...

Thanks

 

[OrangeSkidPlate]

I had the dirtbound fans on my xj. They sure do look cool.....and don't do anything.....the stock fans were way better.

 

[thenag]

I had the dirtbound fans on my xj. They sure do look cool.....and don't do anything.....the stock fans were way better.

I don't think Dirt bound sells fans with the shroud anymore. For every one guy on the boards that you find that likes the electric setup you find 5 that switched back to the OEM setup. It seems like you need to spend a ton of money on high cfm fans. The Mishimoto 10 inch is advertised at 1710cfm, three of those would move some air, but probably not nearly as much as a mechanical fan with a solid spacer.

Also the Dirt bound shroud doesn't seem super sturdy, I am not sure I want to hang $400+ worth of electric fans that close to a $350 radiator on that shroud.

Any chance you still have the dirt bound shroud?

 

[OrangeSkidPlate]

I sold it all years ago. When you say should, do you mean the aluminum sheet that the fans mounted to? I never had an issue with the fans moving or coming loose, just never pulled enough air even with all three hot wired on constantly.

 

[Jay5.9L]

Got a recent quadratec catalogue and saw that DEI has injector heat kit for the 4.0L.

DEI 4.0 kit

 

[Jay5.9L]

Well I ordered one since my CJ 4.0l has that hard starting problem. Will keep you posted

 

[thenag]

Well I ordered one since my CJ 4.0l has that hard starting problem. Will keep you posted

I got one of the OEM style heat shields that comes with that kit, the one that sits on top of the intake manifold. I took it off since it seemed to trap heat at the manifold, with it off air can flow through the manifold (into the bottom of the hood...) Some guys believe that shield is mainly to prevent leaves and stuff from getting through the intake manifold and onto the exhaust manifold where it could catch fire. Seems pretty far fetched but OEM's do some weird things.

I do have the heat sticky tape on my fuel rail and injectors, it helped a bit.

If you have a "heat soak" or "heat sink" issue the non-ethonal fuel, or an electric fan that runs after shutoff are the two best ways to deal with that.

Nathan