Bottom end kit ?

My 89 4.0 has started to grow louder the last couple days. It has a rod knock going on down there. Well, I am thinking of just getting a crankshaft kit if theres one available out there ? I would just swap out the crank and bearings and put her back on the road. I may have a loose wrist pin as well.. so I may have to re ring the motor as well. Can you guys point me in the right direction.. as where to buy a good kit, etc ?

I went through the same thing and needed a new crankshaft and the bearings and all came with the Crankshaft when I bought it from Schucks. I cannot stress enough to replace the headgasket. I didn't and im paying for it now. :tears:

Interesting.. $184 for that deal ? I dont need a headgasket.. so why should I replace it now ?

Another thought.. why not just go stroker ? If I have to fix my wrist pin. I might as well get 4.2 crank/rods ? Since its a Renix.. I have not found info saying that a 4.2 crank works like it would in a 4.0 ho motor. I might as well go with a ho head/intake/exhaust too huh ? I would have to get an TB adapter then if I go this route.

just take the crank out .. get it ground and polished .. new bearing .. hone the cylinders put new rings /or pistons if u want . and all gaskets and ur good to go.. . i wouldnt go stroker.. u might need to clearance the block and a stroker kit cost alot more and i would replace the rods and pistons if i went stroker. ..and of coarse replace all gaskets .. why would u not? .. i would not do a inframe overhaul if i had a rod knock with such a easy engine to throw togeather.. how did u diagnose the wrist pin?? u have to take the motor apart to do that..i dont remember if the 4.0 is a full float wrist pin or a press in .. if its a press in u have to take it to a machine shop to get em pressed in .. and i would go new pistons that route..


******replace the headgasket******* newb mistake... replace all gaskets if ur gonna take the engine out .. .. last time i rebuilt a 4.0 it cost me $750 for everything ?*but my cousin works at the best machine shop in san diego ..

dan89XJ said:

Interesting.. $184 for that deal ? I dont need a headgasket.. so why should I replace it now ?

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something like that, it's been a while. I suggested the headgasket so you could spare yourself the extra labor in the future. just a thought. I think you should do a stroker. arty:

I'm thinking.. budget stroker. The recipe is out there, and no mention of needing to clearance the block.. but I'm not a expert. Anyone have good links to a 4.5L stroker upgrade ? For the wrist pin diagnose.. I bought the jeep with a knock in the motor at idle, and put almost 20,000 miles on it since then. It sounds like a bottom end knock, but it hauls ass and just knocks at idle. So, I figured - its piston slap. I agree with you, it'd prob have to be fixed at a machine shop.. so thats where the 4.2 rods come in play. It wouldnt be much more to go 4.2 stuff.

like i said . i dont know if u need to clearance the block.. ive only done ford and chevy strokers.. and u have to clearance the bottom of the cylinders so the rod bolts wont it .. .. but heres one on ebay .. cant go wrong with ross pistons and eagle rods.. check it i found one on ebay http://cgi.ebay.com/ebaymotors/Jeep...rQ5fTruckQ5fPartsQ5fAccessories#ht_500wt_1182

STROKE IT!
www.jeepstrokers.com
Www.angelfire.com/my/fan/selection.html
All the info you will ever need!

wanaB4x4 said:

like i said . i dont know if u need to clearance the block.. ive only done ford and chevy strokers.. and u have to clearance the bottom of the cylinders so the rod bolts wont it .. .. but heres one on ebay .. cant go wrong with ross pistons and eagle rods.. check it i found one on ebay http://cgi.ebay.com/ebaymotors/Jeep...rQ5fTruckQ5fPartsQ5fAccessories#ht_500wt_1182

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1200.00 is kindof a lot.. you can find the parts yourself for half that price!

Nice links.. I think I found what I need to know. So, I better start a new post over in the street performance section about a stroker build(yet another one, I guess it'll be boring too)