Resealing the magnum..

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j par

j par

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So I've had my 98 Dodge 5. 9 for about 8 months now and my wife and I absolutely love the truck. Seems to burn a quart of oil about every hundred and fifty miles though. No smoke out the tailpipe and not a drop on my driveway? LOL I'm going out on a short limb here and assuming my intake manifold gasket is toast. I'm pretty sure I have a small rear main gasket leak of some sort and valve covers are pretty ugly as well. The game plan is within the next month or two to pull the motor and put it on my motor stand. I want to give it a complete regasket cleaning up and repaint. Probably a nice corporate blue instead of the black so I can see any new oil leaks and also I'm old school and like that old school color LOL. I should say here that this motor is just now approaching a 130k miles soon so I believe there is a lot of life left to be had here. So far it looks like I'll be going to Hughes for there intake repair kit? I'm not big on the hype that they sell, but I also think they do have a few good products. The one thing I have purchased from them I'm happy with (The Rocker set up for my La motor). Sometimes it's separating the hype from the good products can be the trick LOL.
Of course if you know my duster you know I like my engine bay to be extremely clean. I don't care if the rest of the ship is not ship shape but that motor and compartment must be immaculate. And that doesn't necessarily need to be expensive but clean. obviously I'm going to be into this a few hundred dollars at the very least along with some tune up parts and whatnot. I was hoping I could get some advice and some things that worked for others? What products and procedures have you used on your Magnum? There's a lot of cool stuff when I research, but budget must be kept under control. I just don't want to miss something easy I could have replaced along the way that wasn't too expensive? I sure appreciate everyone's time and experience if they got a comment I'd sure appreciate anything and any knowledge...
Thank you..
 
I would start with a good pressure wash while it is still in the truck.
Do a leak down test for a baseline.
Then a complete gasket set from Fel-pro.
Hand lap the valves in, don’t pay any attention to the cracks between the intake and evhaust valves.
New timing chain and oil pump.
Put it back together.
 
I wouldn't pull the heads if there is no issue there. Everything else sounds like a plan. Hughes plenum kit, good gasket set, maybe put a timing set on it while its apart. Yes, 130k is nothing. I have had several of them and 300k is not a problem. My old 5.2 out of my Dakota had 192k when I pulled it to swap the 5.9. You could still see the crosshatch in the bores and pushed the pistons out by hand with zero ridge.
 
I think there are some selling that plenum fix for about 60 bucks now on ebay

P.S. - if those heads are cracked you can always have them pinned :poke:
 
j par said:
So I've had my 98 Dodge 5. 9 for about 8 months now and my wife and I absolutely love the truck. Seems to burn a quart of oil about every hundred and fifty miles though. No smoke out the tailpipe and not a drop on my driveway?
A quart every 150 miles? I has to be going somewhere.
Click to expand...
Click to expand...
 
1 quart of oil per 150 miles is 0.2 oz per mile. If it’s a steady leak into the combustion system, you wouldn’t see any smoke from it.

Calculate it out and assume that you are averaging 30 mph at 1500 rpm.

0.2 oz = 6.4 mL
30 mph = 1 mile every 2 mins
2 mins = 3000 revs
6.4 mL divided by 3000 is 2 micro-liters

For reference, a single drop of oil is 40 micro-liters
 
I did the Hughes plenum kit on a 99 5.2 Magnum. Worked great. First time I just replaced the gasket and then shortly thereafter, she was using oil again!!!!! Lesson learned
 
Mine does the same jada said it was my plenum gasket. switched to 5 quarts 40 weight and one quart of Lucas and so far so good I will check it later and give you an update but last time I checked i was over 500 miles and hadn't lost a drop. Before I made this change I had lost 4 quarts in about 1200-1500 miles maybe.
 
Years ago when I had to do the intake on my 98 Jeep Grand Cherokee 5.2, didn't have kits dedicated to the fix. Service manager and neighbor at the dealership said they prick punch the gasket surface on the intake, glue the gasket to the plate, worked for me.

Your results may vary
 
If you want to know for sure. Open the throttle blades and look at the bottom of the plenum with a flash light. If it's leaking there will be a small pool of oil toward the back of the engine. Most of them leak BTW.
 
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