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98 TJ Engine Swap

Posted: Sun Jan 24, 2010 3:50 pm
by tsouth07
Rings or the valves are bad in the jeep so I am thinking of replacing rather than rebuilding. It's only got 115k and is a damn shame. Any advice or tips? Engine sizes? Trying to possibly get a little more horses than the old 4.0 but am trying to keep my transmission. Simpler the better. Also know anyone who may be getting rid of a compatible engine??? Thanks

Posted: Sun Jan 24, 2010 4:02 pm
by zach119
how much you looking to spend? you could put a stroked 4.0 in it which would have more horses and bolt right up.

Posted: Sun Jan 24, 2010 9:23 pm
by tsouth07
That's certainly an idea, dont know if it's really an option. Would really depend on how much the 4.0 was. Thinking 500 bucks would be in the ball park figure. That's total I'd like to spend on that engine. Best I can do, and yea wish me luck finding a stroked 4.0 with that...

Posted: Sun Jan 24, 2010 10:30 pm
by BadAssEddie
piston rings and valves are not that big of a problem, ud spend probably more time in doing a swap (esp if you are not going with the stock engine). A simple tear down, replacement of the worn out parts claen it and slp it back together, would prob be the best way to go

Posted: Mon Jan 25, 2010 5:07 am
by TerryD
A used engine with a 6mo warranty is minimum $500. Then you have to replace (should replace) water pump, hoses, thermostat, plugs, wires, cap, rotor, and other tune up items. An engine swap like this usually costs from $800-$1000 by the time it's all said and done.

I think I'd do more looking and make sure what's going on. What makes you think it's the rings or valves?

Posted: Mon Jan 25, 2010 9:29 pm
by tsouth07
Snagged a motor from a YJ for $200. New rings, cam, crank, ported and polished heads. All seals were just replaced. Quality engine to say the least. As far as getting that 91 YJ 4.0 in my 98 TJ... I understand I may run into some ecu issues. Please elaborate on these as well as any other thoughts. Thank you all

Posted: Mon Jan 25, 2010 9:38 pm
by TerryD
Different head, injectors, intake manifold, exhaust manifold, sensors, and pretty much everything. They even changed some of the block design. The 98 engine was like a 94 or 96 through 98 run. They changed again in 99 and went to yet another cylinder head design. You've got your work cut out for you...

Posted: Tue Jan 26, 2010 12:39 pm
by tsouth07
Indeed I do have my work cut out for me. I understand there are some distict differences in the two engines. Have to make it work though. Needing some advice/suggestions please!!!

Posted: Tue Jan 26, 2010 4:42 pm
by TerryD
I think I'd try to sell that 4.0 and make $100 on it to go towards the correct engine. You'll save money in the long run by doing it right.