xintersecty

2006 Grand Cherokee 3.0 V6 240K plus miles

My head gasket blew and lost one my cylinders. I suspect this is going to be a top end overhaul. However when I was in the engine bay, I notice some oil from the main accessory pulley from the crankcase on the front. I suspect that the seal on that is gone. If the front is gone, then the rear might be a gonner.

So here is my question, how hard is to pull the engine? I got the equipment. I could do the top end overhaul in the engine bay OR pull the engine and put it on a stand.

Suggestions Ideas are welcome.

97grand4.0

240k miles? You will be immediately and sorely disappointed if you only do the head. Take it from me I just did that. While tempting to do it, it is after all the easier part and therefore more tempting, but, ..and it's a huge but.....with that many miles .....

xintersecty

I plan to use re-manufactured heads and just replace them. The local shop took too long and charged a lot. What do I need to do with the bottom replace seals and rings?

97grand4.0

Um, more than that. Cylinder clearances, new pistons, bearings, cam, hone or bore, oil pump to name a few. and I would leave off the timing chain tensioner as the FSM makes no mention of it and they break and don't do anything anyhow but may make noise that you will never track down. Also have the machinist be sure to measure the cam preload bolt and either set it up with the spring and pin, or with a custom pin and no spring, depending on the clearances. Jeep did a typical poor job with this, and if the cam walks you will have all kinds of noise problems with the valves.

dave1123

That V6 is a delicate and sophisticated engine to begin with so even I, who has been rebuilding engines most of my life, would be reluctant to tear into one. I've seen Patriot's and Compass'es engines totally destroyed just by a jumped timing chain. BUT that's just me and my opinion.

97grand4.0

Oh it's a V 6. Ok then what I was saying was the cam preload bolt may not apply. Or it may idk. And my paper was late.

dave1123

ROTFL! "And my paper was late!" Is that a dig at me? Seriously though, my experience with engines is dated and I've forgotten a lot, but I do know I wouldn't want to try my hand at a 3.0 CRD. If you're talking about either the 3.7 or 4.7 OHV engines, maybe. Still, I doubt it unless it belonged to a family member with a little understanding that I'm not familiar or comfortable with them.

xintersecty

A lot of engines are delicate and sophisticated. It's a miracle that they even work.

I have done some things in the past like, replace my rangers engine with a junkyard engine. I have pulled and rebuilt heads on a chevy aveo. I have replaced a short block on a seadoo boat. But I am reluctant to rebuild this engine because of the increased cost. So if it's that far gone that means about 2.5 to 3.5 K to replace the engine with a remanufactured one. Or I can go with a junkyard engine with a good going over with lower mileage.

So is this engine really that hard to rebuild?

dave1123

First of all are you talking about the 3.0 common rail diesel or the 3.7 OHC gas engine? I'm not doubting your ability, but there's a lot to consider with even just the cam drive chains and getting everything timed right. Then the cams run directly on aluminum and a warped head can bind up the cam. And I know NOTHING about rebuilding a turbo-diesel.

Any engine from a junkyard is a crap shoot at best, in my opinion. Even if it's guaranteed, I wouldn't want to change it twice! Your best bet on that route is a used engine from a reliable source that has been inspected and tested. If you want to keep the truck, My advise is to go with a tested and guaranteed used engine or a remanufactured one. OR you can try fixing it yourself. Your choice.

xintersecty

The 3.7 OHC engine. I made a mistake in my original post. My truck has the 3.0 V6. :-D

I bought this truck for 1400 and I have sunk about 600 bucks into various repairs to get it going. The head gasket thing just blew recently. It took a while before I got that identified with the disappearing coolant. So replacing the heads with remanufactured is 800, an engine rebuild kit is 350, and various things is 200 for a total of 1350. So it's not too far from a remanufactured engine.

So how do you find a "used engine from a reliable source that has been inspected and tested"? I have not seen those and that might be the best option.

dave1123

My mechanic searches the web to find anything he wants. That's where he found my rear axle and t/case. He gets engines the same way. Usually they are out of wrecks because of body damage and are totaled. It's a lot different when you are a business looking for parts. When I looked at remanufactured engines on the web, they will only ship to repair shops or you don't get the guarantee. The returned core has to be bolted to the shipping pallet with the original bands also.