Rockfrog

Capped off the vacuum port and idle is back down. Now I have an exhaust tick, yay ... Probably a warped manifold.

I can pass my original 88 manual along if anyone wants it, not really much good to me anymore.

That's the one, and I have the airbox line going to the manifold ... Probably means I found my high idle issue ... Crossing fingers.

Mine is not like that one, that would be a better one. Mine has the vapor in from tank, and another originally hooked to the intake airbox. No vacuum motor/valve on top at all. Has a carb line (but it's plugged off). Gonna just unplug the manifold line and cap it for return trip home and see what happens. Is that the newer Chryco replacement? Mine says AMC on it.

Anyone think the placement of the EVAP hose maynbe my high idle issue? Out on the water at work right now but i head back to land and the MJ tomorrow afternoon. Was looking at some stock vacuum drawings and the EVAP was supposed to go to the airbox before the throttle body, not the manifold like I added it. Almost wondering if I might repurpose the egr vacuum solenoid to use as a purge valve? Even though the egr system is no longer in use due to the 99 intake manifold, it should still open up at WOT no? Would that be a good time to introduce fuel vapors?

I go a kick out of it ... It's a jeep thing ... Does anyone REALLY understand? Oddly though, everyone I talk tells me how cool my truck is, anyone that drives it loves it. So ... Meh!

Should be PB74 for 88 motor to 94 trans

Having a hard time deciding on a paint color, ran the gamut from lime green or solar yellow to an AMC racing red/white/blue scheme, then decided on just metallic blue .... now, I'm not so sure again. It will be a cheap job, no expensive paint for this poor fellow. All I have decided outright so far it the trim will be black. I don't like red (my daughters choice), and have even considered a recoat in white. Too much time to think out at work I suppose.

And just so you know ... A 1310 series ujoint doesn't know if it's 2wd or 4wd. My 2wd 88 MJ uses the same ujoint as my 00 4wd XJ (just that the 2wd uses far less of them). I used a ballpoint press myself, make quick work at home or on the trail.

I ran TJ coils on my XJ for a while. They were 3.5" and netted 2.5" of lift. My understanding is this is due to the differences in spring rates and the leverage of the engine placement (XJ motors sit more over the spring, TJ's more behind them).

When you do it'll be with SAE sizes. Far less SAE on my XJ but still the odd bolt. My 88 is about a 50/50 split, but the last month I've been working in the engine bay and front clip.

So it was idling at 1000-1200 again after a 250km highway run... Is it possible that I created a vacuum leak when I plumbed the EVAP cannister to manifold vacuum instead of to the air inlet just post filter? Was just thinking of how I set it up and that came to mind. Probably going to look for a new cannister from something at the JY with a smaller profile if I can and move it to the empty spot under the air filter making room for an HO filter adapter and a less messy (compared to Renix) oil change. Currently the purge line is run into the forward vacuum fitting on the back of the intake manifold. Thinking that may have been a mistake. Easy enough the check on the way home Wednesday I guess.

I have a 3.55 27 spline 8.25 to throw in eventually... Guess it's just culture shock coming from the XJ on 35s and 4.56s Update... Way more power in 1st through 4th even some in 5th once I sorted out the IAC and a few vacuum leak issues.

My 88 MJ, 5spd non A/C has the smaller one. My 00 XJ, Auto with A/C has the exact same one.

To swap them, you need to change out the lower ball joint to the WJ/JK type (upper is the same for all years). The JK apparently uses a GM taper and you'll need to check ujoint to hub spacing. WJ's need a spacer but I'm not sure the JK uses the same knuckle (brakes and TRE's are different). Haven't seen much info on JK knuckle swaps but it would make more sense as a ujoint stub shaft is readily available (not so for WJ and why the spacer and late model TJ/XJ bearing is needed). Going to talk to a buddy on the way home Wednesday and see if I can get his JK knuckles for a comparison (he has a spare housing).

First run went well, fair bit of vibration the first 100 or so km, but smoothed out after that. Rotors were pretty rusty from sitting so had a good pull here and there as they cleaned off. Steering stab is shot, and the shocks are toast but semi functional ... Probably hit that next days off. Power seems a little light on the top end, and there is a stumble on deceleration only. Temp is bang on 195-210 and cycles with the thermostat so one less worry. Oil pressure is just over 40 cold and just under hot with hot idle just above first mark ... About typical for 5w30 in this motor, plan to change it out for 5w40 rotella when I get home again. Given the piss poor life this motor saw before me, I'd say it's doing fairly good. Idle is back up to 1000-1200 hot, have to wait for Wednesday to see what it is cold again. Thinking I might try a 2.5L idle circuit, maybe even a throttle body as well, to bring up intake velocity. Thinking maybe the 4.0L circuit is too fat for my setup. I dunno, posted a thread on the subject to get some input. Plan to hammer the wiring one day. Have no left Park lights but pretty sure it's just a ground, was no wire on the vehicle side and it "looked" like it was spliced to the right side after the plug ... Guess I was wrong there. Turn signals work fine, so easy fix. Just that annoying "bulb out" indicator driving me nuts for the last 250km. Still need to get a 97+ antenna base to get the radio working again. Any way that's it for this week, back to work again.

So, just made the first run in the Ratmanche .... Seems a little down on top end (maybe just in my head, haven't driven her since june). Hold steady in 5th but not a lot of pull available (probably due to 3.07s and 235s). Anyway, to the meat, I was thinking about something I read about adding the 99 intake to earlier 4.0s and it was about a reduction in intake velocity causing a top end power loss. Any thoughts on this? I do have a 2.5L throttle body available which is the same size bore as the Renix TB (at least to my eyeball Guage they appear so) ... Any merits to the theory? I was also thinking I might swap the 2.5s IAC housing onto the stock 94 TB in an attempt to reduce the idle (hot idle is back up to 1200 or so rpm, have to wait til Wednesday to see where cold idle is again). Only other issue on the first 250km run was a slight stumble on deceleration only. Otherwise she runs smooth as a babies bottom.

Yep, my 88 2wd uses a hub/rotor similar to most cars (hub is the rotor, inner and outer bearings no with an inner seal) And needs periodic cleaning/repacking. I have a 2000 2wd front axle that uses all the same parts as my XJ but just has a dummy shaft in the unit bearing.

Hammered on her hard today, need to get to work at 3am tonight (this morning?) so... Header on and all body work lined up, lighting tested ... And she passed the burn to the ground test. Bled the brakes, added GM lowering shackles, slapped the old bumper on for now and Torqued the suspension. Then started slapping the interior back together ... So she's gone from this ... To this so far ... So far I'm happy, but lots more to do yet.

Not looking at SOA's just yet, really just want about 2" in the rear... If I add a second main leaf should I see about 1.5-2" and increased load capacity? Or should I be adding the shorter leaves in? I'm already adding longer shackles so the spring height is in addition to that. Thanks

She's sitting on her own wheels again. Just need to bleed the brakes, and Torque the control arms. Leaving just the header panel install. Wired up the front swapping my corroded to crap 88 plug for a 2000 XJ plug and harness adding a relay system at the same time. Decided to call her Ratmanche ... since bodywork, well, just isn't. Work called me back a week early so pretty can come later I guess.

Everything you need to know. http://comancheclub.com/index.php?/topic/44420-MJ-Renix-to-HO-Oil-Filter-Adapter-&-O-ring-Data My Renix kit cost me $1.92

Your Fastenal guy was .... Less than useful ... Lets use that term today, I'm feeling chipper since the MJ is almost done-ish. The Renix TPS bolts are 8-32 (there may also be another size though as my BWD TPS came with bolts but we're too small a thread), the HO bolts are M5 ... Pretty standard parts. I can get the lengths if you want.... But you'll have to wait ... Kids bedtime, and lunches to be made.

Sounds like a little bit of everything .... Pop the valve cover and look for loose Rockers and or twisted pivot bridges. Sounds like there may be a bit of rod knock in there as well (but it was awfully faint). Was that a cold start or was it up to temp, may be piston slap. My 88 sounded similar before I parked it, replaced rods and head (had one, otherwise it would have needed new rockers, pivots and bridges). Mine did not have that louder deeper background knocking, the ticket no is top end (rockers and pivots most likely). Anyway that's my guess on that one, but Internet diagnoses are generally just that ... A whole lotta guessing, based on past experience (but ain't it all?).