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Unread 02-07-2012, 04:34 PM   #31
Peter Nuss
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I think these will be the major issues with the carbed 4.0 swap in your jeep.

1) If you have the stock 5 speed trans, the pilot bushing need to go to a machine shop and be cut down to 1 inch to fit the crank/flywheel. (I had a similiar issue putting in my NV3550 trans)

2) Use the power steering pump, water pump and alternator etc. from the 4.0 (standardize the belts)

3) Grind the 2 tabs off of the bottom of the 4.2 intake manifold for clearance (you'll see where when you try to fit it)

4) 4.2 had a mechanical fuel pump mounted on the block. The 4.0 does not have a provision for one. You'll need a low pressure electric fuel pump available in auto parts stores.

I probably missed something, as I haven't done this swap. But, I would if my 4.2 suddenly dies.

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Unread 02-08-2012, 04:03 AM   #32
JeepJon15
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Hey guys, thanks for all your posts. Glad to hear a couple other guys are doing similar projects... but i hope you were not forced into the situation like me haha.

Anyway, i think i'm bumping up my budget. I got to thinking long term, and if i really want to start sinking major money into her, i may as well do it right. That being said, i want to stay as close to stock as possible.

I'm strongly considering going with a re manufactured 4.2. That way ill have a simple bolt in that will be hard to mess up (for someone who knows what theyre doing.) I'll also still have a solid, basically new engine. I'm a little confused on the small/big block though.

Isn't the 4.2 a small block? I was told that if i order a small block engine, the head would not be included and that i should get the big block. I was under the impression the only difference was the spacing between the cylinders?

If there is any major reason i should still go with the 4.0 (im staying carbed) please, let me know. But now, since i'm getting a rebuilt engine either way, the 4.2 makes the most since for me.

I know Ebay was suggested for used engines. But is there a place where someone has had a great experience with a re manufactured engine? I'm in central ohio so local would be awesome, but i expect ill need to order one.
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Unread 02-08-2012, 05:40 AM   #33
laybackman
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Quote:
Originally Posted by JeepJon15 View Post
Hey guys, thanks for all your posts. Glad to hear a couple other guys are doing similar projects... but i hope you were not forced into the situation like me haha.

Anyway, i think i'm bumping up my budget. I got to thinking long term, and if i really want to start sinking major money into her, i may as well do it right. That being said, i want to stay as close to stock as possible.

I'm strongly considering going with a re manufactured 4.2. That way ill have a simple bolt in that will be hard to mess up (for someone who knows what theyre doing.) I'll also still have a solid, basically new engine. I'm a little confused on the small/big block though.

Isn't the 4.2 a small block? I was told that if i order a small block engine, the head would not be included and that i should get the big block. I was under the impression the only difference was the spacing between the cylinders?

If there is any major reason i should still go with the 4.0 (im staying carbed) please, let me know. But now, since i'm getting a rebuilt engine either way, the 4.2 makes the most since for me.

I know Ebay was suggested for used engines. But is there a place where someone has had a great experience with a re manufactured engine? I'm in central ohio so local would be awesome, but i expect ill need to order one.
You mean short block VS long block. Short block does not have the head attached. A long block does.

Another alternative but not likely to happen; You could find a runnning 4.2 locally. Buy it and have it rebuilt at a reputable machine shop near you. Talk to your mechanic about that option.

Severl major engine rebuilders have been mentioned numerous times here and on other forums. Jasper engines comes to mind. BUT, it would be nice for any member to chime in here and tell you which company they they bought their engine from.

One other possibility is for your mechanic to further inspect your engine. There is the slimmest chance that it could be rebuilt....keep in mind I did say slimmest chance.
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Unread 02-08-2012, 10:10 AM   #34
JeepJon15
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haha, yeah i guess i did mean short vs long... thanks for clearing that up.

I found a 4.2 on CL thats complete and already pulled. Engine and ALL parts (alt starter water pump) are included for like $150. I'm waiting to hear back from the guy, see how many miles are on the thing. He didnt say whether or not it ran, so it may not be rebuildable, not sure yet.

So... still looking for a 4.2, ill check out Jasper engines and see who other people have had a good experience with. What would be the benefit of having a 4.2 rebuilt vs buying one thats already rebuilt? Just the shipping and core charge?
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Unread 02-08-2012, 10:26 AM   #35
laybackman
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Originally Posted by JeepJon15 View Post
haha, yeah i guess i did mean short vs long... thanks for clearing that up.

I found a 4.2 on CL thats complete and already pulled. Engine and ALL parts (alt starter water pump) are included for like $150. I'm waiting to hear back from the guy, see how many miles are on the thing. He didnt say whether or not it ran, so it may not be rebuildable, not sure yet.

So... still looking for a 4.2, ill check out Jasper engines and see who other people have had a good experience with. What would be the benefit of having a 4.2 rebuilt vs buying one thats already rebuilt? Just the shipping and core charge?
If he went to the trouble to pull this engine maybe this engine is a decent running engine. Who knows??? Let thius guy tell you why he did pull it. Was it out of his Jeep? Is hee doing a part out on a rotted out Jeep?

I would ask to pull the base to make sure nothing 'fell off' and is sitting in the base pan.

Also make sure the crankshaft rotates smoothly. Pull the plugs while rotating the engine and note if you have compression in each cylinder when you come up on the compression stroke for each cylinder.

If the seller gives you any crap then stuff your $$$ in your pocket but do it real slow then tell him OK, Thanks any way an slowly walk away. You already have one boat mooring you do not need a second one. Maybe this guy can set it up to start/run for you. If he will do that thenthrow some extra $$$ at him. More money can turns a NO into a Yes real fast.

Maybe you could spin in a new set of crank/rod bearings and swap out the oil pump before it goes into yuor YJ.
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Unread 02-08-2012, 12:50 PM   #36
JeepJon15
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Well, in the add it does mention he had 2 yjs and made one. Leads one to believe he used the good engine and is trying to get rid of the bad one. Though, he could have had two good 4.2s and just used the one with less miles... wont know until i look at it. Still haven't heard back from him though.

So i discovered autozone sells engines. Anyone ever bought an engine here? They all have 3 year warranties. I'm a little unsure of which to get. They range from $1600 to $2150. The main difference i am noticing on them is the crankshaft snout length. It ranges from 2.06-2.5. Also, some are for aluminum valve covers, some are not. Can anyone help me out here??
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Unread 02-08-2012, 02:28 PM   #37
40dog
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150 is cheap for a " good" engine. If i am planning on selling a engine from a donor vehicle i always at minimum run the engine for a proposed buyer.If you cant hear it run, you maybe buying a $70 scrap value engine for 150. Many years ago i bought a engine and didn't hear it run first. Shortly after i installed new gasket kit and setting it in the car we noticed a tapping knock sound.3 weeks later it spit a rod thru the oil pan . Out 350 for the engine 65 for the gasket kit all the time for the swap . Lesson is always hear it run " if i had heard it run i would have probably thrown a set of rods and main bearings in it or not even bought it at all."
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Unread 02-08-2012, 03:14 PM   #38
JeepJon15
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Sound advise 40dog. He never got back to me so i'm guessing it was either bad or already gone.

I was impressed by Jasper engines website. They look like they do a very good job. They also come with a 3 year 100k mile warranty and free shipping to my area. Their 4.2s are about 2,000 bucks with a 500 dollar core charge. These are reman engines, not rebuilt... they thoroughly explain the difference.

I think ill go with these guys and have my father's mechanic friend put it in for me. He mentioned possibly replacing the water pump and any sensors as well, in case overheating damaged them. My water pump is only a year old. Its not that i dont trust his opinion, just wondering if there is a good chance these components were damaged.

I'll update anyone who is interested on the official price once i order the engine. There are enough threads of this type of project, but ill be snapping pictures for my own record when i can if anyone would benefit.

I think i'll be happy i did this once its done, but this is the biggest investment i've made in my YJ (including when i bought it with 116k on 'er.)
Anyone who's put a stock reman motor in who'd like to chime in??
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Unread 02-11-2012, 11:29 AM   #39
Peter Nuss
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I would not be impressed with a good website, here's some compliants:

http://jasper-engines.pissedconsumer.com/

Now, all engine shops have their faulty engines from time to time, it's how you resolve the problems that count in my book.

If you take a rebuildable engine core to a local machine shop, maybe one or two guys will be working on it. They generally do a good job as they are local and depend on their good name for business. Their name goes on the work so they have a personal attachment to the quality. They put in good parts and and try to insure it's built correctly, because they don't want it come back on their reputation. Big businesses that rebuild engines have lots of guys working on it. Some care to do a good job, most probably are there for the pay check. The company has it name on it and no one has personal ownership of the work. Engine warranties are worthless. If the work is done correctly and use good parts, who needs a warranty? I would not favor a big business shop over a local shop with a good name. You could check the local better business bureau also. I'd only use a big shop to get an engine and sell the vehicle as they are generally a little cheaper, because they generally mass buy parts of a lower quality to insure profit. Of course local shops make take a little longer to get quality parts and get the work done as they are usaullly busy. But, if long term ownership is the goal, I would check around for a local shop. YMMV

Oh, the remanufactor vs. rebuilt is total BS hype, meant to confuse the issue. There's nothing wrong with a junk yard low mileage engine that's undamaged either. I would not get one of their engines after visiting that website and reading that nonsense.

Good luck with your project.
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Unread 02-11-2012, 01:15 PM   #40
lobukjeep
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I think Jasper engines are Dookie.We have dealt with Jasper at work and use their engines only when we have to.I cringe every time i or someone else has to put one in.I don't know if we just get crappy rebuilds because we are a big fleet shop and they give us the "garbage" or what.We have had engines that overheated and we took then apart and it turned out to be the coolant port in the intake was completely blocked.Which shows you they didn't even look at it when they installed it.We have also had more than one just self destruct.We have had some good ones also but the success to failure ratio is not very good.Gotta remember,they only replace severely damaged or worn parts.That's it.So if something is in spec then it gets re-used.So god help you have a component that is in spec by 1 thousandth of an inch and then it takes a big crap-ola in 7 months because that item finally fails.Now of course i am exaggerating a little but you get my point.Just look at a couple places before you decide.
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Unread 02-11-2012, 01:20 PM   #41
lobukjeep
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I personally agree with Peter Nuss.I would much rather have a junkyard engine(given proper inspection) and rebuild it or have it rebuilt than buy one of those.
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