Mac8 MJ

[Mac8]

Started a new project, got a 1990 MJ with the inline 6 and 4x4. I installed a rough country 4.5 inch lift, and 31's. while I was in there I replaced the front brake lines, calipers, and pads. Problem is I'm not able to bleed them or get fluid to the calipers. Thinking I got a master cylinder problem. Any help is much appreciated.

[gogmorgo]

Did you let the master cylinder run dry? You'll need to bleed it first. Also make sure the bleed nipples are pointed up on the callipers. The casting is the same for both sides, only difference is where it's drilled for the nipple.

[DirtyComanche]

Sometimes the shuttle valve in the distribution block will shuttle one way or another and then fail to reset when you go to bleed it.  Smack it with a screwdriver handle and see if it helps.

[Mac8]

Will do. Thanks for the info.

[Mac8]

Well, I got the fronts to bleed but not the backs. Got other issues, stuck in 4 wheel drive, and smoke coming from the exhaust and dip stick!

[Mac8]

 

 

Sent from my iPhone using Tapatalk

[DirtyComanche]

Is it actually stuck in 4wd, or is the indicator light just on because the vacuum switch is screwed or the CAD won't disengage?

 

Smoke from the dip stick ain't good.  Make sure it's not overfilled with oil, then compression check and go from there...  The engine is probably less than healthy.

[Mac8]

Nope, it's stuck

It'll get a make over after hunting season

 

 

Sent from my iPhone using Tapatalk

[Mac8]

Also, where is the full cap for the radiator? Just through the overflow tank?

 

 

Sent from my iPhone using Tapatalk

[DirtyComanche]

Just the pressure bottle cap (it's not actually an overflow tank).

 

If the system is drained you often need to bleed it.  A steep hill may help with this.

[Mac8]

Man I wish I understood. The only place that I can fill or even check the fluid level is on the over flow tank. I'm not liking it. Not sure why it's set up this way and not sure that it's factory. I'll try to post a pic tomorrow. Also I'll post a pic of the flatbed I'm going to try and build.

 

 

Sent from my iPhone using Tapatalk

[Mac8]

But without the tire mounted in the middle....

 

 

Sent from my iPhone using Tapatalk

[Mac8]

Any vendors y'all would recommend for a wiring harness?

 

 

Sent from my iPhone using Tapatalk

[MeanLemons]

What kind of wiring harness

[Mac8]

For the inline 6. Motor harness for now. I'm going to get a new motor and was figuring I'd replace it while I'm there if it's a 100 or so.

 

 

Sent from my iPhone using Tapatalk

[Mac8]

Will a 4.0 out of a wrangler (2000 model) work? Someone told me something about crank sensor?

[Mac8]

Finally got around to doing a few things

 

 

Sent from my iPhone using Tapatalk

[Mac8]

And fought this.....

So I'm not sure if I need to rebuild, replace, or go a different route?

 

 

Sent from my iPhone using Tapatalk

[DirtyComanche]

That looks bad.  I'd guess there is more to the story though.  I'd suggest doing a leakdown test to confirm that there is definitely dead cylinders.  Or take the head off and just visual things.

 

If it is dead, find another 4L.  The 87-90 Renix version would be the most direct swap, but you can use a HO from an XJ Cherokee or ZJ Grand up until they stopped building them, but be careful with TJ/WJ engines as the later ones have different mount bosses on the block.  To make the CPS work if you're using a HO engine you have to retain the flywheel or flexplate you have.

[Mac8]

Thank you sir, it'll be making progress over the next few days. My plan is to pull the head and see what's going on before I start making big decisions.

 

 

Sent from my iPhone using Tapatalk

[Mac8]

Decided to stick with a 4.0. Is here anywhere in particular that you guys like to get your motors from?

 

 

Sent from my iPhone using Tapatalk