Magnum engine misshapes..,

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j par

j par

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My 98 3/4 ton 5.9 gas was steaming mad today...
151k on the clock.
Driving to work I thought I smelled what seemed like wires burning???... Only one stop off the freeway and was idling a little rough... Got to work and smell seemed still there but faint..
Truck sat for five hours and I start it and take it up to 2k and hold for a few seconds and noticed a cloud of what looked like white smoke... I shut it off and kind of thoughtful.? Then I started again and let it run and it's puffing white smoke and I'm like well head gasket blown...
Of course I try to drive it home and hit the freeway and I'm really not having any problems with it. Not overheating and before I left I left and there was no water in the oil... I got home and no water in the oil and not see any dead cloud smoke or steam...
This ever happened to anybody else and it not be a major problem to fix? As far as I know I'm in for taking the heads off...
Thank you for everybody's time and experience..
 
My experiences with the magnums (I've owned a few) has not been that experience. As you know, 5.2/5.9 share the same heads. Heads are known to crack, but usually not in a place where it hurts the running. But that doesn't mean yours didn't. If I remember correctly, you replaced the intake plenum gasket ????? ?? Your confident it was white smoke and not blue ? I agree, early indication seems like a head gasket. Do you have dual exhaust? If so, coming from one pipe or both?? Spark plugs will tell a story.
 
Ouch, hate hearing that! How much coolant has it lost? While you’re looking at the spark plugs do a compression test. And if there’s not anything really obvious, maybe invest in a bore scope camera for a phone or tablet. After it sits overnight, you may want to pull the plugs out and have someone spin it over while you watch. You might see it blow coolant out one of the plug holes. And, in the event that one or two cylinders has substantially filled with coolant, you may keep from risking a hydro lock event, too.
 
318willrun said:
My experiences with the magnums (I've owned a few) has not been that experience. As you know, 5.2/5.9 share the same heads. Heads are known to crack, but usually not in a place where it hurts the running. But that doesn't mean yours didn't. If I remember correctly, you replaced the intake plenum gasket ????? ?? Your confident it was white smoke and not blue ? I agree, early indication seems like a head gasket. Do you have dual exhaust? If so, coming from one pipe or both?? Spark plugs will tell a story.
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Thank you 318 I'm 100% confident it was steam that smelled like coolant LOL... It's still retains the factory two pipes that go into the catalytic converter and come out as one... I did put the Hughes sticker on my core support and wrote the date of November 2019 so that's when I did the intake manifold. The good part about that is when it comes off I've already broke the bolt that was going to break and I already drilled it out LOL.,
Of course right now I'm finishing up my 74 truck with 600 miles on the brand new engine and redoing the head gaskets on it. I'll try and wrestle that out by this weekend and then starting on this truck. After all this by the time I got home from work yesterday I just had enough of head gaskets... Two trucks and 2 weeks with blown head gaskets it's like winning the lottery but NOT..:(...
 
j par said:
Thank you 318 I'm 100% confident it was steam that smelled like coolant LOL... It's still retains the factory two pipes that go into the catalytic converter and come out as one... I did put the Hughes sticker on my core support and wrote the date of November 2019 so that's when I did the intake manifold. The good part about that is when it comes off I've already broke the bolt that was going to break and I already drilled it out LOL.,
Of course right now I'm finishing up my 74 truck with 600 miles on the brand new engine and redoing the head gaskets on it. I'll try and wrestle that out by this weekend and then starting on this truck. After all this by the time I got home from work yesterday I just had enough of head gaskets... Two trucks and 2 weeks with blown head gaskets it's like winning the lottery but NOT..:(...
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Yeah, not a good streak to be on..... I agree, already having the intake off before will be a huge blessing. Hopefully your luck changes quickly, because though not unheard of, it's still uncommon for these to kick head gaskets. I've had them with a lot higher mileage, and my truck is at 307,*** currently. I'm confident you'll have both trucks on the road soon.
 
Hope ist not the head or head gasket. I'll will say that I over heated my Durango real bad one winter. Twenty something below and I just started it and drove to get home without warming it up at all. Thermostat stuck and I pegged the gauge and kept driving, it was too cold to stop. Didn't even replace the thermostat and never had any problems after that. Kept the engine and sent it to the crusher with 300K.
 
Did you smell it in the cab or was it coming from under the hood or out the tail pipe? Something you just smelled or could you see it?
 
It didn’t suck the gasket in on the bottom side of the intake did it? Is the oil level down?
 
318willrun said:
Yeah, not a good streak to be on..... I agree, already having the intake off before will be a huge blessing. Hopefully your luck changes quickly, because though not unheard of, it's still uncommon for these to kick head gaskets. I've had them with a lot higher mileage, and my truck is at 307,*** currently. I'm confident you'll have both trucks on the road soon.
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Really hoping to have the white truck back and running very soon within the next couple days. But of course that's just a fair weather truck... Fortunately we have other vehicles but I need to get the green truck well sorted out before snowmobile season that's for sure...
With 150k I was certainly not expecting any major problems as well...
 
I have a bore camera if you need one. The lead on it is plenty long to get wherever you need it, and it will fit easy down a spark plug hole.
 
j par said:
Steam out the tailpipe no question...
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Cracked head, head gasket, or a intake gasket leak into a cylinder or runner. Pull the plugs, one will be washed. At least you will have it narrowed down.
 
Power wagon is "so far so good"...
Monday I plan on starting the process of pulling the engine...
 
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Joy ...
 
The one you boob video I watched they took the front bumper off but I don't really see the need for that. Likely it was to accommodate their cheap harbor freight engine hoist that doesn't have a long reach...
 
Just about ready to pull... Just have to take out the two bottom easy bolts trans to motor and one easy motor mount bracket to block bolt on each side...
Hopefully I'll have it on the engine stand tomorrow...:thumbsup:
 
Well it's definitely #8.... Clue number one, the cylinder had a half cup of water in it when I pulled the head.... It was the only piston that looked new??? And the only valve area that is wet looking...
Looks like I'll have that head pressure checked and hope for the best...
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magnum head cracks are usually easy to see. wire brush the area between the valves and look for the crack.
 
You can get a set of reman heads from allied motor parts for $550 , the last pair i got came with free head bolts and a complete gasket set
 
A crazy deal popped up on craigslist last night on a 75 la 360 and short shaft 727 and I was first one on it .. when I picked it up I mentioned I needed a magnum head and he had two sets...
I bought a set for $60...
Took my head to the machine shop today and most all valves had cracks in between them but the number eight that had the water in it the cylinder had a much more noticeably larger crack in it... It was quite obvious it was toast so I didn't leave them
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at the machine shop. At that point I had decided to buy a new one but ran into these two that looked near perfect with zero cracks from a 318 but I don't think it matters...
 
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