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New engine, one line

gluktar

NAXJA Forum User
Location
Canada
I have a 2000xj that is a daily but also relatively capable and sees the trails every few months. Its got 350,000Kms (220,000miles) on the original motor and runs ok in general. However, I have a motor that I pulled from a write off sitting on a pallet that I know nothing about except that it ran really well before it was pulled, has only 200,000Kms (120,000miles). Was thinking of just dropping it into my jeep and then I can tinker with rebuilding the old 4.0l over the next who knows how long as i have the time and money.



So here is the request. Give me a one line answer on what is an absolute necessity to do beyond just dropping the new engine in. Or what is some magic tip (I haven't installed an engine before but I pulled one so how hard can it be:). With the engine out am I crazy to not replace the ______ or check the _____??? In other words, I'm not asking you how do I swap an engine, I'm looking for someone to save me a headache or three.


Thanks
 
While it is out I would pull the oil filter adapter, oil pan and timing cover and replace all those gaskets as well as the rear main oil seal, front crank seal, the timing chain, timing chain snubber and the harmonic balancer.

As a second line (yeah, already breaking your guidelines) I would try to assess how well the cooling system has been maintained and consider whether or not freeze plugs need done. Freeze plugs are not a common problem on 4.0Ls, but given your scenario and my acquaintance with Murphy I can see one of those failing just for fun.

The above answers assume that you are already planning to replace hoses and motor mounts as part of the engine swap.
 
While it is out I would pull the oil filter adapter, oil pan and timing cover and replace all those gaskets as well as the rear main oil seal, front crank seal, the timing chain, timing chain snubber and the harmonic balancer.

As a second line (yeah, already breaking your guidelines) I would try to assess how well the cooling system has been maintained and consider whether or not freeze plugs need done. Freeze plugs are not a common problem on 4.0Ls, but given your scenario and my acquaintance with Murphy I can see one of those failing just for fun.

The above answers assume that you are already planning to replace hoses and motor mounts as part of the engine swap.

I'd add to this, replace the rear lip seal. Also, a full timing chain set, not just the chain itself. Check the trust bearing. Check to see how far in and out the crank moves. If and when you take out the freeze plugs, look inside the water jacket. Especially, the rear one. I had buildup on a JY motor I had. I've recently been burned on a second JY motor. Since I was going to replace about everything anyways, I'll be OK.
 
Thanks for the tips and the bonus lines. When I was researching pulling the engine I found a great tip about the e12 bolts at the back of the bell housing. Bought the fancy tool for it only to find that the previous owner must have already pulled it and replaced the e12s with standard bolts. It took quite a while to figure out why the special fancy tool did t fit.
 
LOL!

Murphy always finds a way to sneak in.
 
I'd add a new or rebuilt water pump. Not much $$. Stant thermostat. I have or do grind out a radius in the Thermostat body, where the tube intersects.
 
Don't try and pull the engine from the trans without removing the CPS.

Pressure wash everything before you start.
 
“Confirm the donor fits, then install it”.
Replacing gaskets turns into a ton more work really quick. That’s not to say don’t replace an obviously leaking gasket… only you know the condition of the donor!
 
Must admit that'd be my approach, although:-
the oil filter adaptor O-rings are a known failure - & well nigh impossible to do in situ
rear oil seal is another known problem, but not so sure I'd replace it as preventative maintenance - especially without an engine stand.
 
I would replace all seals/gaskets, check the flex plate, perhaps replace the torque converter because its exposed, replace harmonic balancer to maybe. Make sure the grounds to the engine are spiffy while its out. You may want some new sensors on hand, even after being careful, I had to replace a few once some great help diagnosed what was going on.
 
Typical forum over thinking. Everyone remembers what was wrong with that engine they swapped in 10 years ago, and think yours will have the exact same problems. Yours will just as likely have a different set of problems. Replacing sensors JUST TO replace sensors is for the birds. Furthermore, replacing a 10+ year old OEM sensor with brand new parts store crap is just as likely to cause problems problems as it is to fix them.I
Unload the parts shotgun until you know what your shooting at.
If it ain’t broke, don’t break it.
 
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