[ebrodnick]

After dropping a valve seat I bought 2 brand new cylinder heads from power torque. The install went smooth. Replaced timing set and all gaskets. Engine starts up a seems to run great. Took for a short test drive and after a few minutes the oil pressure dropped to nothing I pulled over and popped the hood and on the top of intake manifold and underneath my k&n cai it was shiny like something had been sprayed on it. I checked around the cylinder heads and all I could see is a small pool around the coil for cylinder #2. (4.7l v8). I don't see how it could be leaking from the head and spraying up to the top of the intake manifold. I replaced the valve cover gaskets and maybe it's leaking from those but I don't think they would cause the drop in oil pressure.

randomly the oil pressure will jump back up to normal only to fall back to 0 shortly after.

 

[ebrodnick]

There is also white smoke coming from passenger side engine and exhaust. Lessens when engine warms up. White makes me think coolant. I didnt use new head bolts because I took a straight edge to all the old ones and all the threads made contact as per the service manual. If I wanted to try new bolts could I just take the old ones out and put in new bolts? Or once the old bolts are removed is the head gasket ruined and a new one is needed?

Thanks all.

 

[Baalic]

Ive not had much experience with these new hemi's but when changing out heads, on other cars, I would always recomend changing the head gasket out as well. A lot of them are only made to be used one time, not sure on the Mopar gaskets personally, but for the 30 bucks it costs for the new gaskets, I don't know why you don't just buy new ones. Also make sure all your bolts are tightend to spec. There are a number of things that could be wrong, but I think you probably need to pull the heads back off completly, to see if you can visually see something wrong. Maybe your lucky and its just a head gasket.

Also I know some bolts are made to be only used one time, so you may pull your heads get new head bolts and gasket and try one more time, if your still having issues, I would have a shop do a leak down test or something.. They may just be bad heads....


Cheers

 

[ebrodnick]

The chances of a bad head at run likely being that they were new, but you never know I guess. I bought new head gaskets for this install. The only thing I reused were the bolts.

 

[Frango100]

If you checked the head bolts for necking and they where all ok, then there is no reason to put in new bolts and it would not solve an existing issue.
Is it continiously producing smoke and was it not residu coolant which is evaporating now?
Does the engine noise change when the oil pressure drops to zero (the lifters would normally start making more noise) or could it be a pressure sensor problem?
No change that some rag or alike dropped into the carter and is blocking the oil pump screen?
I would clean the engine well and then see if any leak can be observed.

 

[ebrodnick]

I was meticulous on the torque sequence as well. the white smoke is coming from the passenger side of the engine and exhaust. It is fairly continuous but reduces a little once the engine warms up. What worries me is the coolant residue that was all over the intake manifold and on the plastic part of my intake tube. Not sure how it could have sprayed up there from the bottom of the cylinder? There isn't a noticeable noise from the valve train when the oil pressure drops. I don't believe anything fell and is blocking the oil pump screen. If it wasn't spraying whatever coolant/oil on the top of the engine Id think the problem was with the oil pump or send unit. I don't know what I could have goofed up on when installing new headgasket and head. Perhaps didnt clean the engine block surface well enough?

 

[ebrodnick]

Is there any correlation to bad head gasket install and oil pressure falling to 0?

 

[Frango100]

Did you use the head bolts torque method as mentioned in the service manual and did you use engine oil on the M10 bolts? The 4 M8 bolts need sealant and no oil on the threads.
In the text below, the 1-10 bolts are the larger M10's, 11-14 the smaller M8's

Tighten the bolts in sequence (Fig. 30) using
the following steps and torque values:​

*

​

​

Step 1: Tighten bolts 1–10, 27 N·m (20 ft. lbs.).​

* ​

Step 2: Verify that bolts 1–10, all reached 27

N·m (20 ft. lbs.), by repeating step-1 without loosening

the bolts. Tighten bolts 11 thru 14 to 14 N·m (10

ft. lbs.).
​

​

* ​

Step 3: Tighten bolts 1–10, 90 degrees.

* ​

Step 4: Tighten bolts 1–10, 90 degrees, again.

Tighten bolts 11–14, 26 N·m (19 ft. lbs.)​

 

[ebrodnick]

For my 02 wj with the 4.7 the torque sequence was...

1-10 15 ft lbs
Then 1-10 35 ft lbs
Then 11-14 18 ft lbs
Then 1-10 90 degrees
Then 11-14 19 ft lbs

I dipped the large bolts in oil prior to installing and put blue thread locker on 11-14 bolts.

I'm beginning to think it has to do with my prep. The heads were brand new but all I did with the engine block was remove the old gasket and wipe it down with a rag. I feel like an idiot for not taking the time to clean the block. Was to focused on the fresh shiny smooth heads.

To address my other question. Would a bad seal of the head gasket be the cause of the oil pressure drop to nothing.

 

[ebrodnick]

Well before I tear it all down again any last thoughts on my situation? I suppose this time ill take more care making sure the engine block mating surface is clean and smooth before putting on another new gasket. New bolts as well. I'm still not convinced this will help with the drop in oil pressure but the fact it's spitting white smoke from engine bay and exhaust isn't right.

 

[Frango100]

I do not see how a head gasket could make the oil pressure to fluctuate. Would be interresting to measure the pressure, to be sure that it is really dropping, or just only an indication problem.
What would you like to solve by using new bolts? The money is yours, but seems to be a waist without a good reason.

 

[ebrodnick]

Well not only am I trying to figure out the oil pressure but the white smoke from passenger side engine bay and exhaust pipe.

 

[2005JGC]

DO NOT TEAR DOWN TILL YOU ACTUALLY TEST THE OIL PRESSURE. Oil pressure senders are decently common and if your dropping out randomly and picking it up randomly I would lean towards an oil pressure sender, obviously being a total S.W.A.G. (scientific wild ass guess).

Coolant, you have the heater core hoses around that side, ensure you dont have leaks... honestly I dont know how long you have run it, but they can smoke for a long time after open heart surgery. Figure out your oil pressure issue and then let it run. It could be your radiator cap leaking externally on the passanger side of the motor... I have seen one that visually was perfect but if you revved the engine up for a couple seconds it would spray externally.

 

[ebrodnick]

I appreciate your response. Hopefully it works out. Ordered a mopar sending unit online since I read terrible things about aftermarket. Seems like an odd coincidence for that to go out at the same time after an cylinder head replacement but I suppose stranger things have happened. if that doesn't work I'll check to see what the pressure is with a gauge to see if its actually low. Will inspect all hoses and cap and see what happens when I give the engine a good Rev. I'm still worried about smoke out the exhaust but it was only running for 15 minutes. Will also check the oil and coolant to see if either look like it has been mixed with the other. Ill be sure to post my results and findings.

 

[ebrodnick]

Put on a Coolant system pressure tester. Saw a dripping leak from one of the heater hoses. Explains the white smoke from that side of the engine. Next was to take a look at the oil sending unit. turns out that the wires for the sending unit were exposes and looks to be causing the issue with the oil pressure reading as the engine seems to be having good pressure. Last was the main leak that was spraying over the top of the intake manifold. Had a friend rev up the engine while I inspected and it was shooting straight out of the valve cover seam. Strange since I put brand new gaskets on it but perhaps they didn't seat properly.

So looks like I discovered the causes for my problems. Going to attack this tomorrow and see how it turns out. :thumbsup:

 

[ebrodnick]

All problems fixed and running great. Thank you all.