2.8 Swap/Rebuild; 2.8 -> 3.1 vs. 3.4

[Canyonero]

I have a spare 2.8L from my truck and a friend that might be wanting/needing a new one for his. Both are '90 Isuzu Troopers.

We're looking at spending at LEAST $500 for a used 3.4L, the only semi-local one we've found is about $800 (I forget what the mileage was). Anything else would need shipped (freight would be over $100).

So, is it practical to rebuild my 2.8L? I've traditionally thought not, but my friend will want to do it on a reasonable budget. What will be my parts checklist to go the 2.8 to 3.1 route? Is there any savings in rebuilding an engine vs. getting a used one?

My old engine was a good runner when I pulled it, but it has 168k on it so I'm not really wanting to drop it in as-is. Also, it would puff some smoke when first started, but didn't smoke at all while running. I never bothered to figure out why.

[Ray Hamilton]

The savings in $$ won't be there but having a rebuilt engine will give you peace of mind where as a used engine can have alot of things wrong with it that won't show up until after installation. As hard as these things are to R&R I would never put a used engine in w/o rebuilding it.
I just built a 3.1 out of a 2.8 for my S10 Blazer. I like the results, but I would have been far better off putting the money in a 3.4.
I got my parts pretty cheap on ebay. A.R.I has the crank rods and pistons for the 3.1 for $500. Then you have heads, cam, gaskets and many odds and ends you'll encounter. I didn't have enough money at once to get a rebuilt 3.4, or the GM crate 3.4 or that's the way I would have gone.
With the 3.1 build you have to use an '87 up oil pan and a front cover that will work with that pan. Then that's determined by if you use serpentine belts or not. Many variables and much research. However, the majority of my research was here.

[Canyonero]

Yeah, I'm putting a used engine in my Trooper, and I haven't been thrilled with the experience. However, I've never rebuilt an engine either (but someday I want to).

[geoffinbc]

Well if you want to try a rebuild the 60degree is a good start. Nothing fancy it builds just the same as a small block. So if you need a visual guide they are not hard to find. There are even a few 60degreev6 specific books out there.

[ssdurango]

168,000 kms isn't alot, If it just puffs smoke, replace the valve guide seals and drive it. Save your money, take your time and do a real build-up that you've fully researched. Learn from my mistakes

-Tom

[Canyonero]

168,000 miles, so about 270,000 km. The engine in there now has about 189,000 miles. Thinking it might just be a lifter, so we'll look into that.