V6 Timing Chain Replacement

The timing chain in my Dauntless is long overdue for replacement. Since I will have to replace it in the parking lot here at school, I want to get a few things figured out before I start to make sure it goes smoothly.

1. Obviously I need to drain the coolant. Will the petcock at the bottom of the radiator drain enough of the coolant out? Or do I need to remove the plug near the rear of the block? I'm hesitant to do this because it will be messy.

2. When removing the timing cover, must I take the oil pump apart? The FSM mentions taking it apart and then packing it with petroleum jelly to make it prime, but if I can avoid tearing into it altogether that would be ideal.

3. Does the water pump have to be separated from the timing cover? I read that it does, but I don't understand why. I just replaced it, so I would prefer not to mess with it again.

4. Should I expect any oil spill out when I remove the timing cover?

5. What size is the crankshaft bolt? Are there any fasteners where torque is critical? I don't have a torque wrench here, but I can make the 30min walk to Autozone if I must.

6. Will either sprocket require a puller to remove, or do they typically slide right off the shafts?

Sorry for so many questions. Normally I would just dive right in and figure things out as I go, but this time I am working in a parking lot with limited tools and time, so I want to be prepared. Thanks!

 

Drain as much water from as many locations as you can, as it will find it's way out to the ground or places it should not be.
The oil Pump can remain on.................but if you have the cover off this is a good time to do a check on it's condition and rebuild if necessary...........this may help ( Blueprint 225)
The water pump has some through bolts to the block so some have to come off...........
There will be oil in the timing cover.
All of the related bolts should be torqued to seat the gaskets.........and I only say that as some that do this work all the time will just use there built in ability to feel how tight it needs to be.........but it's a good Idea to use one during the install and then come back and hand check the bolts once the motor has gone through a few heat cycles.
Most sprockets come right off...........take a pictures as you disassemble......and rotate the motor to become familiar with where the timing marks are and how to align them. There is an oil slinger inside that has to go back correctly, Make your choice early on the type of replacement timing chain set you want to use.......the single chain has rubber bumpers that should also need replacement. The double chain does not use them.
Get all your parts together before you start...........tools , gaskets, sealer, a scraper to remove old gasket materials.............not fun working in a parking lot!

 

I will add that putting a stiff piece of cardboard against the radiator, or removing the radiator(4 bolts and 2 hoses) all together will help you avoid inadvertently sticking a tool through it. I will also give you much more room to work. You usually get some coolant down into the oil pan so an oil change is probably in the works also. Be very careful on the four 5/16" bolts that go through the water pump as they can be stuck pretty well. Most time just working them back and forth slowly instead of just twisting them off will yield better results. There is a bolt just above the oil pump that is easily missed as well as the oil pan bolts that go into the bottom of the cover that must be removed.

 

And save the skin on your knuckles.

+1 on planning for an oil change after reassembly, and before you run it again. A fair amount of coolant will drain into your pan; probably enough to do damage if you ran it.

If I remember correctly, I think the bolt on the end of the crank requires a 15/16" socket. I can't remember the size of the crankshaft bolt offhand, but it's not larger than what you'll be equipped with a basic tool set.

Good luck!

 

all above . me I would bump engine till you have it at TDC on crankshaft timing mark with distributor rotor pointing to number one cylinder . remove distributor and fuel pump . but your going to need a harmonic balance puller . so rent it at auto store when you buy parts

 

That's been up for debate here before. Personally, every one of these engines I've worked on, the balancer just slid off. Maybe first just back out the bolt in the crank a few turns, loosen the belt(s), and see if it wants to slide out without help.

That will also let you know if you'll be able to get the crank bolt loose without an impact gun. Some are easy, some are stubborn.

 

The one I just took off required a puller. Better to have a puller and not need it than the other way around...

 

I got the front cover off today. Plenty of nylon teeth floating around in it. Everything came apart without too much fuss, but the coolant sure made a mess.

One thing I noticed is that it was pretty easy to turn the engine over with a wrench on the crankshaft bolt. With the trans in 3rd gear, I can pretty easily roll the jeep and spin the engine. Shouldn't compression make the engine a lot harder to turn?

 

With or without the timing chain on? If it's off, certain valves would be cracked open and not allow compression on all cylinders.

 

Even with the timing chain off there still should be a near equal amount of valves either opened or closed.........so some resistance should be present.......was the motor turning over when you were pushing it while in gear? If not then perhaps the clutch is history also?

 

Yes, the motor was turning while pushing the Jeep in gear. That's actually how I lined up the timing mark before taking things apart. On my F134 Jeep, I have never been able to move it while in any gear.

 

Spark plugs out?...............If not it sounds like it's got some serious leakage...........like , head gskts, valves, Rings & pistons??? or just flat worn out?

 

It also matters what gear you are in while pushing. 3rd gear will be easy to push while turning over the engine. 1st or reverse will take more effort. The opposite is true if you are turning the crank pulley with a wrench instead of pushing it.
-Donny

 

Another possibility.... The v-6 probably has 3.73s and the f-head probably has 5.38s? Big difference right there.

 

Could it be that the old timing chain is so loose that the valves are opening and closing at the wrong times, causing lack of compression? I don't have the new one on yet. Also, this Jeep has 4.88s, while my F4 Jeep has 4.27s.

 

Fix one thing at a time..........no reason in getting distracted. Once you have done whatever you feel necessary to the front cover, timing gears and chain, oil pump and seal , get it timed correctly and button it up then proceed to do a compression or leak down test on all cylinders. If there is an issue it will show up.

 

Thanks. I'm making more progress, but probably won't finish it this weekend.

Here's a pic of the old timing set. I'd say it was time to change it out!

 

Yep..........Long over due for a change...........might warrant while you have the front cover off to pull the manifold, remove the lifters and then pull the camshaft and take a look at it.

 

Did you check to see if the timing marks still lined up before you pulled it apart? Those stripped teeth may have allowed it to skip a little which would explain the ease of engine movement.

 

The plastic and metal went somewhere. Pull the pan and clean the pickup screen too. Wow, thats really bad.