I haven't done a compression test for a while but I have done them since this issue has come up. And each time it tested fine. I think the engine has to be HOT HOT for this issue to show up which makes it hard to do the compression test.

I think the only way I am going to find it is to tear the engine down.

 

well, it's a pretty good bet you have at the very least a blown head gasket...... If this ISN'T your daily driver, yank the heads, and see what ya got. I would have a look at cylinder walls as well while you were in there.

If you have the budget, I would simply replace the heads, as opposed to spending money on them, even to get them checked. (assuming there isn't any obviously fatal flaws in them....) They are prone to cracking, due to very thin castings. New, BETTER heads can be had for right about 300 bucks apiece, fully assembled. Take 'em out of the box, and bolt 'em on.

 

HeyYou,
I have a set of EQ heads sitting in the garage right now that I had bought for my planned 408 build. Of course life has gotten in the way of that and it has been on hold for at least 6-10 months. So I do think I will tear the engine down and put the EQ heads on it. I have a Hughs air gap intake to install too. Plus some Harland Sharp rockers. Sure would be nice to be able to wheel my Jeep again.

 

That sounds like a very good plan. You should like the nice boost in power you will get too.

 

Well actually last night I got a wild hair up my tush and tore down the 5.9 I have sitting on a stand in my garage. I had bought this engine 2 years ago and never touched it because I didn't have the funds to build my 408.

Well now I am kicking myself in the butt for not tearing it down sooner. The guy I got it from must of had it sitting outside or something. I found rust in a few cylinders, water contaminated oil. Now so far the only issue I can point to with this engine is a blown plenum gasket. Now since it sat with the water in it I am going to pull the pistons and crank. Clean everything up as best I can then install new bearings & rings. I know it isn't the BEST idea to do this but I need to do this on the CHEAP.
So I figure if I hone and (not sure what it is called) use the ball type hone on the cylinders that should clean them up enough to run. Then I will add all my new parts to the engine and swap it into my Jeep in place of the 5.2.

So hit me with all the why nots and then help me to build this budget engine.
I will start a new thread about it.

 

A balll hone or one with 3 stones shoudl work. I prefer the stones unless all I am doing is knocking the glaze off trhe cylinders. I think that is what the ***** were designed for. Parts store probably has a hone you can use. Do not run as fast as drill will turn. Slow and steady, keep moving up and down and keep it oiled. As long as rust isn't deeply pitted, you should be OK. Would be best if you can get engine vatted first. It'll help get any rust out of passages as well. I had the same issue on a Jag engine I had shipped in from Houston a couple years ago.

 

Yep I wish I could get it hot tanked butthere isn't a machine shop close to me that does it. I am going to do some checking and see if I can fid some place. Just to get this thing clean would be nice. And no none of the rust is deep. It was all just surface stuff but it did have the engine locked up until I rotated it back the other direction a few times.

 

Replace the rings if you can spring for them.

 

Rings and bearings are getting replaced. I'll keep the stock cam for now too. Also going to reuse the lifters. I have them seperated by what cylinder and valve they came from. If there something I should do to them before reinstalling? And of course I'll use tons of assembly lube. I am going to call around tomorrow and see if I can find a place to get the block cleaned.

 

For the lifters, just make sure they are clean, but oily.