Here are some pic's of the engine...

PS--After Hesco sent me a new computer the 258/4.0 head/MPI started right up...To say the least I was relieved.../wwwthreads_images/icons/tongue.gif

Robert87yj/wwwthreads_images/icons/tongue.gif
engine rebuild w/4.0 head done, now for the MPI

 

let's see
so you are not sure it is overheating?
just that the gauge is telling you so?

you probably felt the top rad hose to see if it gets hot when the thermostat opens?

engine looks sweet!/wwwthreads_images/icons/smile.gif

my red 87 wants fuel injection too!

would really like a v8/wwwthreads_images/icons/tongue.gif

 

Very nice looking workmanship,
Looks like you paid close attention to the details, and it really shows in the finish product.
Looks better than it ever did right off the showroom floor. Yeah I would get the motor up to operating temp,(idle for about 10 minutes) and simply place your hand on the hoses and see if its really hot, if its not noticeably hot to the touch then start looking for a problem in the sensor or wiring.
Im in need of a new motor at the time, hhhmmmhh How would you like to come out to Reno to take in a Reno BlackJacks Baseball Game(maybe a double header), I have a special parking spot for you. Heck the Beers are even on me, uuhhhhh... but Ill wait out in the parking lot. Ahhh if only they had a team.


Jeff
89 Wrangler
Chance and luck, favor the well prepared.

 

what is that dirty strapping device on the fender by the battery used for. Don't you have a can of black paint laying around. do you really need that device, dosen't it unbolt. You know save weight save gas.

brownbagg

 

Thanks for all of the compliments...

Yeah, I felt all of the tubes. all got hot, so the fluid is going through them. I just took the thermostat out...same thing. I am going to check the wiring next. If that is all kosher, then I guess I'll have to pull the head to see if the water is flowing through it. If I hadn't had someone else rebuild the engine and put on the 4.0 head, then I would know for sure that the water if going through it. I hate having it reubilt, but under the circumstances... time and money necissitated it. I wish I had had the time to do it my self/wwwthreads_images/icons/frown.gif

the uncertianty is killing me/wwwthreads_images/icons/crazy.gif/wwwthreads_images/icons/frown.gif/wwwthreads_images/icons/crazy.gif

Robert87yj/wwwthreads_images/icons/tongue.gif
engine rebuild w/4.0 head done, now for the MPI

 

Yeah , I would have to say it about time you get a little more wheelin time and a little less wrenching time real soon.

Jeff
89 Wrangler
Chance and luck, favor the well prepared.

 

The dirty strappy device holds the jack and the arm that turns it. If I ever have the time to clean it I will, just isn't on the priority list right now. I'm working on a center consul that is framed with 1" x 1/8" angle steel to replace my old one that I made out of only plywood. I wan't something that someone can't take a crowbar to and rip out of my jeep like someone did to my radio 4 years ago...that was a big mess. That way I will feel comfortable putting my CD-changer in there. I guess I'll have to work out a good sealing lid to my design though.../wwwthreads_images/icons/tongue.gif

It is getting hot out side right now, the smog and humidity are necessitating an afternoon nap. I'll work it all out later I guess.

Robert87yj/wwwthreads_images/icons/tongue.gif
engine rebuild w/4.0 head done, now for the MPI

 

Was the new computer set up differently for the rebuild? I have the MPI kit and am planning a rebuild soon and I have heard that you have to reflash the computer to keep it from pinging from the changed compression ratio of the bored over cylinders.
As far as the overheating, is your gauge just reading high or is it actually boiling over into your resivoir? The kit comes with a higher rating t-stat (195 i think?). The MPI requires a higher operating temp that the origional carb set up. If your using the original guage/sender set up your gauge should reflect a higher temp than before.

 

I do not know if you still have the heat riser on the exhaust manifold ,but if you do check to be sure it is operational .I sold a perfectly good chevy once because that thing was stuck and causing it to overheat,The co worker who bought it off me just unstuck it and never had a problem again.Live and learn ....... the hard way.

Ray
Learn to let go of what does not serve you ,but forces you to serve it
why does everyone ask if I am gonna paint it ?

 

I,m just thinking here so please do not get mad at me for repeating a thought.

before I would tear apart, take the thermostat completely out, remove hoses from radiator and stick a garden hose in top hose and see if water run out of bottom, if so cooling not clog.

do same with rad, I know its new but , I do not know it a try

hook back up and crank, run garden hose through rad fins, could be fan clutch. could be something fell in water pump hose( I have kids) tear down would be last step for me

could be gauges my runs 210 all day every day

brownbagg

 

Well..
bad news, Took the thermostat out, it over heated. I let it go until it boiled over...
I'll check on the heat riser, never heard of one, I hope that is the problem, what ever it is...I'll look it up and check it out before I hit the sac tonight...

My dad has Mondays off. He said that he would tear the water pump and head off tomorrow for inspection. /wwwthreads_images/icons/crazy.gif/wwwthreads_images/icons/frown.gif

Atleast it runs finally,...or in other words...atleast there is a light at the end of the tunnel/wwwthreads_images/icons/crazy.gif

Jeepchick's mom is very adimit about me selling it and buying a more reliable car...I don't value her opinion though because she didn't check her oil for a year or so and had to put her car in for maintenance after the oil light came on... Sometimes I wonder which is more frustrating, having a jeep that I can drive, but only in the drive way, or having a future, know-it-all mother in law with strong opinions about jeeps and self proclaimed knowledge about cars in general.../wwwthreads_images/icons/tongue.gif She does make a good quilt though............/wwwthreads_images/icons/tongue.gif...

Robert87yj/wwwthreads_images/icons/tongue.gif
engine rebuild w/4.0 head done, now for the MPI

 

aren't we just full of advice/wwwthreads_images/icons/smile.gif

how long did you run it without a thermostat before it overheated?

it will overheat w/o one on any car.
doesn't give time for the water to cool in the radiator.

if the thermostat was not opening it would also overheat-not trading cooled water for the hot water.

try another thermostat or test that one in hot water to see if it opens. or wait you said the top hose got hot when thermostat was in?

i don't know/wwwthreads_images/icons/tongue.gif

 

It took about 45min to an hour to boil over...with out a thermostat.

I think that there is water flowing throught the head, but possibly not enough. The guy that rebuilt my car is a friend of my dad's and has built race cars and rubilt engines for a living for many years now. Dad says that before he will pull the head he'll go over and talk to him to see what he did to the head before he put it on...

Thanks to everyone for all of the advice...It is one of the only things that is keeping me sane right now. \

I can't even begin to tell everyone what a great help it is to bounce ideas off of other capable and knowledgeable jeepers.

Robert87yj/wwwthreads_images/icons/tongue.gif
engine rebuild w/4.0 head done, now for the MPI

 

I run my engine without a T stat whenever I go to the Hammers. I have never heard of an engine overheating because of a lack of thermostat. It will not get up to propper operating temperatures in cold weather. But I run about 15 to 20 degrees cooler with the T stat removed. The hi po water pump I run(Summit Racing) is designed to move as much water through the engine as possible, the more and faster the water is moving the more it is exposed to the outer surfaces of the radiator core where heat can be released, new cooler water does not need to stay in the engine block to cool, in fact its quite the opposite you want it to move from the water galleys as rapidly as possible to transport the heat to the radiator for release. Im not advocating running without a T stat, but it is helpfull in extremely hot conditions with little or no added airflow of the vehichles forward motion.

Jeff
89 Wrangler
Chance and luck, favor the well prepared.

 

Jeff (H8)

I was considering getting a hi flo water pump, how much do they run? I guess I should go over to summit's site and check it out. I was thinking that the water ports that had to be plugged up would have restricted the flow of coolent possibly. My dad is going over to talk to his friend that rebuilt the engine to see how many of the water ports he actually plugged up... The well is a little dry right now. I'll have to see if there is money to get the jeep running and sitll be able to pay for fall classes. This fall is very important because it is my last one/wwwthreads_images/icons/smile.gif/wwwthreads_images/icons/cool.gif.

This thing has really got me scratching my head/wwwthreads_images/icons/tongue.gif/wwwthreads_images/icons/crazy.gif. Jeez...I was having enought problems with my corporate finance class this summer, I guess murphy figured it out and decided to dish out more...But on the bright side...my climbing buddy came over the other night to pick up his nailgun that I borrowed. We were looking at the jeep and he mentioned taking off the pin-striping and decals off the hood and body. I was worried about the paint underneath being a lot brighter red than the rest of the jeep. He offered to paint it for me. What a great guy/wwwthreads_images/icons/cool.gif/wwwthreads_images/icons/tongue.gif!!!

Robert87yj/wwwthreads_images/icons/tongue.gif
engine rebuild w/4.0 head done, now for the MPI

 

Hey Robert, if it were me, I'd wait to pull the head and do the simple/in-expensive stuff first. Do you have a fan shroud on the radiator? I had a friend once who's car kept overheating. We went through the thermostat thing, engine timing (too far advanced and they tend to overheat) etc, etc. He took it to a local radiator shop and the guy put in a new radiator cap. End of problem. We bought the radiator cap from him and gave him an extra $20 being a straight shooter with us (he could have easily told us we needed a new radiator). Turns out that the radiator needs a certain pressure release to keep everything flowing properly (it's black magic to me). He told us we had a cap with the wrong pressure rating.
Good luck
-Gus-


90YJ 4.2L NV4500 456:1 33's Twin ARB's

 

Its got a fan shrowd on it, proper pressure on the cap...I'm going to wait until my dad has a talk with the guy who rebuilt the engine and put the 4.0head on it. I am also considering a Hi-Flow water pump, if they make one for the 4.2. Until now I thought I had a good undersanding of how the engine cools its self. The coolant is flowing, just not enough. It doens't over heat immediately. I put a 160 themo in it and it hovered around 160 for about 10 minutes before it got any hotter. The water is flowing just not enough...I think...

Robert87yj/wwwthreads_images/icons/tongue.gif
engine rebuild w/4.0 head done, now for the MPI

 

Robert-
If you have circulation, water is going through the head.
Make sure you used the proper head gasket.
It is supposed to be one for a 4.0, not the 4.2 head gasket.
Better double check that for sure.
If you do pull the head, don't worry if you see that there are no corrisponding small round water jacket holes on the 4.0 head that match the four small round holes surounding the 4.2's deck. Only a pair on one side match up. The 4.0 gasket seals the other pair and there are are no corrisponding jacket holes on the 4.0 head.
I hope you aren't doing all this worrying while running the new mill while parked. Yer supposed to be cruising the neighborhood in it, getting good air flow through the neighbor hood.
There's a lot of friction in a new mill.
What shape is your old raditor in?
Did you get it flushed while you had it out during engine rebuild?
Maybe it's a good time for a 3-core.
And yes, you can get a high-flow water pump from FWDHardware.

JAF
http://www.monsterslayer.com/jeep

 

Thanks for the help...

My dad is going to talk to the guy who rebuilt the engine and put the 4.0 head on. I'll make sure to ask him what headgasket he used on the head.

The radiator is new, that is why I am thinking about going with a hi-flow waterpump. But before I make any $$$ decisions, I need to know from the mechanic who rebuilt the engine, how he mounted the head, what gasket he used etc... I'll find out more this evening when I get home from work.--frustrating...not being home to work on it/wwwthreads_images/icons/frown.gif/wwwthreads_images/icons/crazy.gif...My jeep misses me...I can already tell...

Robert87yj/wwwthreads_images/icons/tongue.gif
engine rebuild w/4.0 head done, now for the MPI

 

Correct me if I am wrong here, but won't a rebuild engine run hotter for a while, than the previuos engine did? I am just theorizing because the new clearances in a rebuilt engine are all tighter, and I know that alot of demolition derby cars are built with "loose" engines to prevent overheating.

So maybe a tighter engine will run hotter due to more friction, at least for a little while, until things move around for a while and get looser.

Also what about a lean fuel condition?

Definately check the gauge though. I am just sending out some ideas.

Jesse

What does not kill my wallet, will still make me poorer.
AOL Instant Messager: jessemyers

 

Jesse,
Thanks for the ideas...
I don't think that the tighter tolerances would cause it to run too much hotter than an older engine would. I checked the guage and it is pretty much right on where it should be...
My dad said that the guy who rebuilt the engine said that he used the 4.0 head gasket, but also said that it might need a hiflow water pump...great, just my lucky day.../wwwthreads_images/icons/crazy.gif

Robert87yj/wwwthreads_images/icons/tongue.gif
engine rebuild w/4.0 head done, now for the MPI

 

I do not know anything about this but it is all heresay

I remember something about that one of the head (4.0 or 4.2) had a water jacket hole that had to be welded due to not a hole in the block.

now I do not have the staight six but I read it here on the bbs

brownbagg

 

Yup. thats right there were water jackets that needed to be sealed. The guy that did my engine used some sort of plastic steel to seal the outside water jackets, but that would leave the other two on each of the ones that were welded up. For a picture see Jaffer's site I think the url is
http://www.monsterslayer.com/jeep

The 258 block is convex, rather it curves in between the cylinders and the 4.0 head is straight along the edge that the 258 is curved, half of some of the water jackets are exposed, it wouldn't be enought to restrict the flow that much I would think...

Man it runs like a dream, it just over heats so quick that I don't feel comfortable driving it out of the driveway./wwwthreads_images/icons/crazy.gif

I wish that there were better words than
thank you
for all of the help that every one has given, even if a post wan't particulary helpful, it still got me thinking and was great to be able to bounce ideas around as to what it might be../wwwthreads_images/icons/smile.gif

It's like having a good psychologist, but even better, a bunch of jeep psychologists./wwwthreads_images/icons/cool.gif/wwwthreads_images/icons/cool.gif/wwwthreads_images/icons/smile.gif/wwwthreads_images/icons/tongue.gif/wwwthreads_images/icons/smile.gif

Wow!!! I just noticed that my status changed to enthusiast...I guess that is what jeep problems will do to ya...

Robert87yj/wwwthreads_images/icons/tongue.gif
MPI-4.0head-on 4.2
Man I whish it would just stop over heating

 

Robert,
good to see you got promoted enthusiast, the trick now is to try to get that Jeep on the trail before you make Pooh Bah, I think one or two more complicated modifications and your probably gonna be there. Hope you get that high heat prob solved soon, so you can enjoy that new mill. Its driving ME crazy, just thinking about it sitting there almost ready to go and you cant drive it..... I trully feel your pain brotha

Jeff
89 Wrangler
Ol Murphy(Murphy's law), should be in prison by now, for all times he's kicked the crap out of Lady Luck.

 

I just thumbed through my 4wd hardware catalog. That hi-flow water pump looks tempting at $90-100, that is less than I thought it would be. I looked at summit's website and didn't see anything. there. I'll have to balance the check book and look a the callendar to make sure I'll have money for the bills, but I think I can swing it. I really wanted to be able to drive it on my climbing trip this weekend. This trip is special because I'm gonna' slip Jeepchick the ring. I guess that would make her Official Jeepchick.../wwwthreads_images/icons/cool.gif/wwwthreads_images/icons/crazy.gif although she will always be the same old Jeepchick, besides, Official Jeepchick is a lot to type/wwwthreads_images/icons/tongue.gif

I got some info from the guy who mounted the 4.0 head, I'll post it tomorrow to see what you guys think, right now I'm starting to hear my pillow calling me...

Robert87yj/wwwthreads_images/icons/tongue.gif
engine rebuild w/4.0 head done, now for the MPI