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Build Thread I'm making progress on my project 79 CJ

Build Thread I'm making progress on my project 79 CJ
Guess I can now update my profile. The head swap is done and so far I'm very happy with the results. The newly rebuilt Motorcraft 2100 carb is also working great!
 
Alright lets hear it. Where'd you take it ? How many miles? What terrain? Seat of the pants feel? Cmon I crave details. :drool: Seriously though Im really interested. I have another AMC 258 i6 / 4.2l Im gonna rebuild and am looking for ideas. Love the way you went about it and got it done.
 
Petescj said:
Alright lets hear it. Where'd you take it ? How many miles? What terrain? Seat of the pants feel? Cmon I crave details. :drool: Seriously though Im really interested. I have another AMC 258 i6 / 4.2l Im gonna rebuild and am looking for ideas. Love the way you went about it and got it done.
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I've only driven it around my area of town so far, but seat of the pants feel tells me it is much zippier, it definitely has more power, and the coolest part is it super smooth! I said this before, but it has a totally different personality to it now. It feels more solid. I'm driving it to work tomorrow on the other side of KC. I'll get a better feel for how much I gained on the highway then.

As for the way I just got it done, that's just how I roll. I decide to do something, and I just do it. :D
 
After a real world test drive to work this morning I have an update. On the loooooong uphill on 435 where I use to lose 5 miles an hour with my foot on the floor, with the new head it maintained its speed and I didn't have to put my foot into it. I'd say that settles it. It definitely has more power! :chug:
 
A couple other things to add on the 4.0 head swap. I have to down shift way less often than I did before, and though I haven't calculated the fuel economy yet, I know it's better. Started with a full tank and I've driven to work twice now along with a lot of other driving, and my gas gauge is still on full. It's never gone this far without the gauge going down some.

I ran in to one snag that's worth mentioning. It started leaking oil pretty bad out of the timing cover seal. I replaced the seal and installed a micro sleeve on the balancer but the leak didn't go away! I was really worried that the bottom end was giving out a lot more blow by with the higher compression from the new head and causing oil to be forced through the seal. It turns out that it wasn't that. It was caused by blow by, but not because it has too much. It was because my new Mr. Gasket oil breather was nearly impossible to blow through compared to my old one, and because the 4.0 head has metal restrictor plates in the baffles that hardly let any pressure through. I removed the restrictor plates and reinstalled the baffles without them, and I opened up the breather. Oil leak fixed!

If anyone is thinking it still must mean that I have too much blow by, when I remove the oil breather and PCV valve with it running, it has very little blow by, even when reved up. I know it was the breather/restrictor plates in the baffles causing my small amount of blow by to build up pressure in the crank case on longer drives.

It's amazing how one little thing like an oil breather not functioning well can cause us to work our arses off on something else before we realize it was just the one little thing!

Glad I didn't tear into rebuilding the bottom end with a fresh bore and new pistons, only to find it still leaking because of an oil breather! :eek:
 
Rescue Diver said:
As for the way I just got it done, that's just how I roll. I decide to do something, and I just do it. :D
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No doubt about that. Congratulations on your build.
This has been a great read.:chug:
 
My gut just turned thinking "what if my AMC 304 was blowing so much oil due to something stupid like a clogged PCV. But then I realized it was blowing a quart a week!!!!!!!

I think I feel better believing it was just a bad bottom end....PLUS I got a 360 out of it!
 
hybridmoments said:
My gut just turned thinking "what if my AMC 304 was blowing so much oil due to something stupid like a clogged PCV. But then I realized it was blowing a quart a week!!!!!!!

I think I feel better believing it was just a bad bottom end....PLUS I got a 360 out of it!
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Mine probably would have lost a quart in a week of my driving, but it was more than a clogged pcv. The brand new Mr Gasket breather I bought might as well have just been a solid plug before I opened it up. Thankfully my AMC 258 i6 / 4.2l doesn't make much blow by. It just couldn't breath at all.

But going to a 360 was a plus either way for you, so who cares why you did it?:D
 
I figure it's as good a time as any to do an update on my build thread. I've been driving my CJ with the new head on it for about a year now, and all I've had to do to it is change the oil every 3000 miles, and tighten a bolt or two that were trying to work their way loose. I drive my old Jeep to work on the far side of town most days to save putting the miles on my "Daily Driver" BMW, and it never misses a beat! :D
 
I finally swapped out the really crappy riding Rough Country 4" lift rear springs!!!! Rough Country suspensions really live up to their name. Even after removing a leaf from each side, they were still way too stiff for my light weight fiberglass body.

I picked up a new pair of Superlift YJ rear springs for only $65 each and they made all the difference in the world! It's great not getting my teeth jarred every time I hit a small bump in the road! I stayed with the Rough Country front springs for now. With the weight of the motor over them, they don't ride too terribly bad, but I still plan to eventually replace them with a pair of Superlift YJ front springs. To do that I'll need to replace the CJ's stock 2" front spring hangers with 2-1/2" rear hangers and I'll also have to make a few other changes to accomodate the wider springs.

A couple of days ago I got out the arc welder and fabricated a Jerry Can mount that'll bolt directly to my home made spare tire carrier. With only a 14 gallon tank, it'll be nice to have a place to carry a few more gallons, just in case. I'll post pics up once I have it bolted on and my new Jerry can arrives.
 
I decided to take a couple of new pics on break just now. :D
 
Man Rescue Diver it looks Great! Good to see another Midwest Jeep! I know I have been following your Head Swap in the other post and you have been a big help. Looks Great Buddy especially Topless!!!:chug:
 
Got a few more things done. I installed heavy duty shackles, and I finally replaced the weak factory lockouts. Oh, and I finished the Jerry can mount.
 
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Hey Rescue,

Where did you find a 2 inch hitch? Can you take a close up so I can see how it is mounted? And maybe post the manufacturer? I need something strong enough to hold a bike rack with 4 bikes! Thank You
 
Renegade said:
Hey Rescue,

Where did you find a 2 inch hitch? Can you take a close up so I can see how it is mounted? And maybe post the manufacturer? I need something strong enough to hold a bike rack with 4 bikes! Thank You
Click to expand...
It's just a bolt on type receiver hitch that you can pick up at most hardware stores. I welded it to my home made spare tire carrier. I use it for my bike carrier, and I also have a 4x6 utility trailer that I tow with it.
 
I decided to get the welder out once again. I'd been thinking of adding a steering box brace for a long time, and somehow the ones they sell for $70 with the collar that clamps around the round lower part of the box didn't look very solid, so I decided to design my own. At the bottom of the steering box there's a tab in the casting that was just begging to be drilled and tapped to use as a great mounting place for the brace. I bought a $2 piece of square steel tubing, cut it to length with the proper angles, welded tabs on each end, painted it and bolted it to the tab on the box at one end, and bolted the other end to the existing extra tapped hole in the bottom of the passenger side of the frame.

I can't believe the difference in how tight it steers now! I had no idea it was flexing so much!!!
 
Next on the agenda is a heavy duty tie rod that I ordered last night. After that I'll be adding an Aussie locker to the front differential, and soon I'll be welding the AMC20 axle tubes to the housing, adding a truss, and installing solid 1 piece axles in the rear. I'm thinking of going with a posi in the rear instead of a locker because I don't want all the clicking and popping you get with a locker for daily 2 wheel driving.
 
Man Rescue that engine looks great! :chug: I know we both have the same set up, it looks like we are both about at the same stage. I checked with my paint shop and it was going in the booth today. I will be happy to get it back. Keep up the great work, looks great!!! Following this post till the end!!!:popcorn:
 
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