tarmac2dirt

Hello, building a 4.0 for my jeep Comanche. This is a stock rebuild not a stroker. i have started checking all the gaps and clearances and have come up with no recommended ring gap for parts i have bought. The pistons a sealed power h802cp and matching ring set. There are no ring gap notes anywhere in the boxes, as compared to the stock pistons the sealed power pistons are hypereutectic and i know the ring gap needs to be wider than stock specs. i have come across the Keith black spec chart and it shows .0065 per 1" of bore dia. Is this applicable to all hyper pistons?? Out of the box i have .017 on my top ring and .017 on 4 and 2 at .018 on the second ring gaps. Keith black hyper specs calculate to about .025. should i go with .0065 calculations? comparing the stock and new pistons the top stock top ring land is at .321 and the new hypers are at .245, much closer to the top. I have also decked the block .020. What would be a some of your suggestions for the proper end gap. This engine will be a dd not needing any performance of race type specs. Thanks for any advice, Paul

Getting ready to order the second half of the parts i need for my engine build. Orig header pipe is cracked so i have to to get a new one. This is a 1994 block, head and intake going into my 88 MJ 2wd. Theres this ATP header #101212 on rockauto $205 any have experence with this or do step up to a better one. Can't really afford the banks header, are their other options that I'm not finding. can someone maybe give me some insight on something good and quality wise or is the ATP header decent. Thanks, Paul would anyone care to see pics as i go through my build

ive run across an issue with the knock sensor threaded hole in the block. The threads in the block where the sensor goes is very rusty and crusty. Looks like about half of the threads have rusted away. This block is a 1994 which i guess they did not have the sensor? Any way has any one done repair work to the threaded hole as put an insert in there or any other option to fix it. I'm using this block in a 1988 MJ which is of course a renix electronics . Thanks, Paul

i am going to go ahead and remove the p/s pump to rebuild. the radiator will be out not the a/c condenser; water pump off was really concerned about the intake and header.

As the topic says, how much of the accessories can be left on an engine when removed. when i get around to pulling mt engine for the swap i would like to do most accessories om the engine stand. Such as intake, header p/s pump and alt. this will be done with the trans off. hood off and the radiator support in. What can you guys tell me if any has to come off. I will also be doing this by myself, i will have no help. Thanks, Paul

Will be building a new engine soon (4.0) for my 88 MJ. At the same time I'm going to replace the clutch. What are you guys using as a good upgrade clutch for an engine with very minor mods. LUK--Precision--MPAC--ECT. so many to pick from off rockauto. At this time, I'm just collecting some parts before i dig into the engine parts for pistons and cam. This will be a dd and not a stroker engine, just a good built 4.0. I had a clutch replaced in 2007. but don't know what brand it was. It served me well. Please let me know what you or your buddies believe is a good replacement. Thanks Paul

Ok guys, a few answers about cams and using certain spring pressures, but your not answering my question. can a thrust plate type cam be used in a early type block. The cam companies do not have the early blank cores to even grind a cam. I did find one company that has some blanks for 1999 and newer ready to make me a custom cam but will it WORK thats what i want to know. The cam cores for early blocks seem to be hard to come by for cam grinders. Any hope to get the correct answer here. Thanks

i'm starting a new engine build 4.0 starting with gathering the parts needed. Seem like the 96 cams are like getting fresh dino dung. Can the 97 and later cam be used in a 1994 block. I know it has a retainer plate the can be eliminated by using the early cam bolt and button up front. Is there any other problems that stops me from using a newer type of cam. Oh yes i know comp cams shows early cams available but their quality is crap so no comp stuff for me. thanks Paul

Ok, gives me the work plan on what i need to do. Have to pull pan to see were a load knocking noise is coming from. i screwed up and left a scott paper towel in the filter intake and now created a lot of work ahead. thanks for the answers, Paul

need to pull the oil pan and was wondering if the pan will come off with engine in the chassis. Looks like there is enough room. this is a 1988 2wd MJ if that matters. thanks Paul

Well it seems to have dropped about 4mpg from what it used to be. Ran a trip of about 120 miles and refilled the tank and calculated at 13.8 mpg. does this seem low to you guys. This is a stock 1988 MJ long bed 2wd 4.0 engine with 706 injectors and a 60mm throttle body cruised at 65 with a/c on one way and off coming back home. Tires are a little larger 30x9.5-15. I kinda thinking the O2 sensor is bad, happened once befor about 10 years ago. change the O2 and got my mileage back. Does it sound like the sensor has gone bad again. probably has about 60k since the last sensor change. Is that about limits for an o2 sensor 60k miles. I'm going to go ahead and chane it but is the any other things killing the mileage, MJ is at 200k on the clock so it is getting tired too. thanks Paul

As the title shows the chrome trim work above and below the grill. Going to try and refinish the shine but not ruin the metal. A magnet will stick to it but that doesn't mean its a pure stainless. Doesn't look like its chrome plated I'm just not sure. Anyone have an answer. to this. Thanks

thank you gogmorgo going out to start working on it now.

Would you think that i have now ruined or stressed the TRE with too much torque??

looking to see if someone has the correct torque for the tie rod ends. The write up i found shows to torque the TRE to 80 ft lbs which i did (maybe he meant 80nm). Now I'm afraid the i have either streched the threads or stressed the TRE ball stud. I'm going out in about an hour to pop everything apart inspect and retorque all TRE nuts to 55 ft lbs unless someone has a TSM that shows the correct torque. Most XJ websites shows 55 ft lbs. I would greatly appreciate any feedback to the correct torque. Thank you, Paul

OK, here is the link---

After more searching i found a good wright up on DIY section here on CC page 5, as if anyone else wants to know.

i'am going to change all steering parts tie rods, draglink tomorrow. This is on a stock 2wd 1988 MJ. I replaced the track bar a couple of months ago and now this has messed up the alignment. New track bar same length as orig, but now tires are pushed to the left steering wheel is also off. Truck has 200k so it's time for some new parts. Any way where is the starting point for adjusmnets. My guess is the dradlink going from pitman to the right wheel would be the first adjusment and then adjust toe in too the left wheel. Is this correct? Just wanting to get it close enough to drive to the alignment shop. Appreciate any answer that i can go by. Thanks, Paul

Thanks, guys, for the answer. I had done some web searches and found out the glass is the same but seems no one mentioned the nibs. Did see some complaints about the gasket quality though. I think I'll chance it and leave the nubs on in case the next owner wants it to change it back orig. Sometime after the holidays i will get it the w/s replaced along with the gasket set up. Thanks again Paul

Hello, once again i have a question. Going down the freeway yesterday i had the windshield right trim blow off. I believe someone posted something about going to a later rubber trim 1997+. I know the w/s needs to be removed to do this but how about the fitment to my 1988 MJ. Do the clip tabs need to be cut off or can they stay. Is it even possible, with good results. i only have the oem upper and lower trim pieces left no side pieces now. Thanks Paul

Hello to all, main question is for the ring gear. Bought a new gear set (for a mopar 8 3/4) switching from a 4.30 to 3.73 gears. The 4.30 ring gear when new i had to heat up some to put on the carrier. now this new set 3.73 ring gear just slips down on the carrier. I do not feel any side movement or play in the fit just that it didn't require heating up to fit the carrier. Has anyone had a ring gear that slipped on or must the fit of a new ring gear always require some heating to expand the gear and fit the carrier tight. Thanks Paul

Any thoughts on excessive water blasting out the tail pipe during the first startup in morning. I know that condensation will put a little water but i think mine is more than just condensation. This has been going on for a few years and would like to hear what you guys might say. Cracked head or head gasket bad. This is a 1988 renix 4.0, were they known for cracking heads like some of the later 90 model 4.0's I live in a dry climate to, southern New Mexico desert. Coolant does drop slowly from reservoir but i think this is from a bad heater core as i can smell coolant in the cab. Please give me your thoughts, Thanks Paul

Thanks for posting the pics eaglescout . Long piece below the letters is what i need. Hope to find a good used one with no dents. Thanks

posted a couple of years ago and still looking for the upper grill trim like the one pictured. either painted of chrome and no damaged to it. if you have one or know were one may be available please pm me.thanks

Looking and have searched here through nearly 100 pages here and can 't find my answer. I then went to the naxja web site and found just one answer and wasn't thrilled at all. Can some one verify that the dash pad is or isn't a removable piece. naxja said that it is not removable and is glued to the main dash. Can this be true. not removable ?? i wanted to remove my dash pad and have it redone when i pull the complete dash for a heater core change. Thanks for your time. Paul