I'd go ahead and replace the crank sensor while you have the intake off. Also the valve cover gaskets.
Planning on replacing plenum gasket
2
Hi guys.
1996 5.2 ZJ ltd.
My ZJ had several issues since I bough it 6 months ago. Last time I got the throttle body off, I looked inside and there was some oil, not much, but it's shiny down there.
I borrowed a cheap inspection camera from a friend, to take a better look, here are the best pictures I could take (not much):
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Some bad plenum gasket symptoms are there, bad mpg (10), oil consumption (more on this later). I had some hesitation at higher RPMs when hitting the gas pedal hard, but that went away when I did the injectors swap. I don't know about power loss because I don't have how to compare.
There are a couple of other issues that I'm not sure if are related. I'm loosing a lot of oil, I did 600 miles since I bough it and lost a qt. I checked everywhere and there are no signs of oil leaking. I've been having considerable amount of white smoke on idle (even when the engine is warm), but it's white, doesn't smell like burned oil, and the coolant level doesn't drop.
I thought of a blown head gasket, but the coolant level not dropping baffles me.
Anyway, back to the plenum gasket fix, I'm going to buy the Hughes kit with Felpro gaskets. And while I do this I plan to replace some other stuff:
- Thermostat (195º)
- Both O2 sensors
- Rotor and distributor cap (just because I'm taking the intake out)
- Coil and spark plug cables (because I have to do that eventually, and I'm changing cap and rotor, I dunno)
My questions are:
Is there anything else I should be changing/buying/taking a look at while I do this?
I have a standard tool set (wrenches, sockets, etc), do I have to buy something else than a torque wrench and a fuel disconnect tool?
Any help will be appreciated, thank you!
1996 5.2 ZJ ltd.
My ZJ had several issues since I bough it 6 months ago. Last time I got the throttle body off, I looked inside and there was some oil, not much, but it's shiny down there.
I borrowed a cheap inspection camera from a friend, to take a better look, here are the best pictures I could take (not much):
Some bad plenum gasket symptoms are there, bad mpg (10), oil consumption (more on this later). I had some hesitation at higher RPMs when hitting the gas pedal hard, but that went away when I did the injectors swap. I don't know about power loss because I don't have how to compare.
There are a couple of other issues that I'm not sure if are related. I'm loosing a lot of oil, I did 600 miles since I bough it and lost a qt. I checked everywhere and there are no signs of oil leaking. I've been having considerable amount of white smoke on idle (even when the engine is warm), but it's white, doesn't smell like burned oil, and the coolant level doesn't drop.
I thought of a blown head gasket, but the coolant level not dropping baffles me.
Anyway, back to the plenum gasket fix, I'm going to buy the Hughes kit with Felpro gaskets. And while I do this I plan to replace some other stuff:
- Thermostat (195º)
- Both O2 sensors
- Rotor and distributor cap (just because I'm taking the intake out)
- Coil and spark plug cables (because I have to do that eventually, and I'm changing cap and rotor, I dunno)
My questions are:
Is there anything else I should be changing/buying/taking a look at while I do this?
I have a standard tool set (wrenches, sockets, etc), do I have to buy something else than a torque wrench and a fuel disconnect tool?
Any help will be appreciated, thank you!
1 - 20 of 27 Posts
3
It may be that after the twelve bolts are removed / broken, that the plenum to head gaskets and the plenum to block gaskets are cementing the plenum to the engine.
Has all the stuff been moved aside / removed from the front of the engine to permit unfettered access? The power steering pump / bracket should be flopped to the drivers's side, the generator should be removed, the A/C compressor should be flopped to the passenger's side and the generator / compressor bracket should be removed. Once all that is gone, then there is plenty of access to pry / pop the plenum off the engine.
The wall thickness is better for prying under the thermostat and is very thin under the coolant hose. Try starting in the front passenger's side corner.
Ensure that the TSB 18-48-98 for the spark plug wire routing to correct cross-fire ignition is performed.
Pick up a fresh set of bolts, because the TSB 09-05-00 sequence stretches the bolts. I got my bolts from Rock Auto and the quality is great.
Edit, link broken so TSB attached.
Chase the threads on every bolt and every hole. Check that every pan bolt can be finger tight w/o the pan and w/o the pan gasket prior to assembly and torque per the TSB. On mine the crud would have prevented proper pan tightening / sealing w/o chasing all the threads. These are blind holes and the bolt clamping force will be wrong if the bolt bottoms out in the hole instead of clamping against the pan.
The small coolant bypass hose can be changed during this service.
The lifters could be removed, cleaned, reassembled and replaced during this service.
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Has all the stuff been moved aside / removed from the front of the engine to permit unfettered access? The power steering pump / bracket should be flopped to the drivers's side, the generator should be removed, the A/C compressor should be flopped to the passenger's side and the generator / compressor bracket should be removed. Once all that is gone, then there is plenty of access to pry / pop the plenum off the engine.
The wall thickness is better for prying under the thermostat and is very thin under the coolant hose. Try starting in the front passenger's side corner.
Ensure that the TSB 18-48-98 for the spark plug wire routing to correct cross-fire ignition is performed.
Pick up a fresh set of bolts, because the TSB 09-05-00 sequence stretches the bolts. I got my bolts from Rock Auto and the quality is great.
Edit, link broken so TSB attached.
Chase the threads on every bolt and every hole. Check that every pan bolt can be finger tight w/o the pan and w/o the pan gasket prior to assembly and torque per the TSB. On mine the crud would have prevented proper pan tightening / sealing w/o chasing all the threads. These are blind holes and the bolt clamping force will be wrong if the bolt bottoms out in the hole instead of clamping against the pan.
The small coolant bypass hose can be changed during this service.
The lifters could be removed, cleaned, reassembled and replaced during this service.
You can pull the whole assembly as is and set it on the passenger's side fender - no need to remove the A/C compressor or alternator from the bracket at all
Other than that, info provided by Wingless was pretty much spot-on. I had four of the intake manifold mounting bolts snap (all of the ones on the front- and back corners), which required pulling the heads. I ended up installing aluminum heads, but the stock ones could've been re-used after drilling out the old bolts. ..and no, I could not get the bolts out by welding a nut on top of them. They were solidly freezed on the heads.
As for the intake manifold cementing against the cylinder heads: my intake was stuck pretty damn good. I had to use a crowbar to carefully pry it free. As was mentioned, pry where the material is thickest on the intake manifold. There's a sort of a small lip on it that is pretty handy on sticking a prybar or crowbar under it :thumbsup:
Knocking on wood...
The engine rebuild kit I purchased included both molded rubber and impregnated cork front + rear block-to-manifold gaskets. I used the cork gaskets and also purchased four of the Mopar 4006 583 gasket dowels, to hold / align those gaskets.
There is RTV in the corner joints, per the FSM.
These gaskets have held up fine, for less than a year, so far.
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The engine rebuild kit I purchased included both molded rubber and impregnated cork front + rear block-to-manifold gaskets. I used the cork gaskets and also purchased four of the Mopar 4006 583 gasket dowels, to hold / align those gaskets.
There is RTV in the corner joints, per the FSM.
These gaskets have held up fine, for less than a year, so far.
I tried them as well, but couldn't get them to seal. Tried twice
:shhh:Then used RTV, and zero issues. If you look at most Dodge forums, they all suggest using RTV in place of the cross-over gaskets, no matter if they are OEM style or not.
1 - 20 of 27 Posts
