ok A buddy of mine just bought a 77 power wagon that was one of them military 1 1/4 ton ones i think they were.. well anyway its got a 360 that was rebuilt anout 1000 miles ago it has an edelbrock manifold with a holley 700 or 750 4 bbl carb... it just started smokin out the tailpipe very bad he runs it to and from work and it burns about a quart of oil a day.....Head gasket???? valve seals???? what could it be???but it is very white smoke..while its ideling and even if hes only goin 10mph...any info is greatly appreciated and also we would like to convert it from full time 4x4 to part time...can i just get a set of louckout hubs or is there more involved????...thanks alot
Probably the intake manifold gaskets are bad, a very common small block problem. My 77 had major problems with it, until I used the right gaskets, and some insanely bad smelling glue on them.
I had 3 360 powered vehicles, a 74 Roadrunner, the 77 PWagon, and an 86 Ramcharger, and all had to have the gaskets changed at least once. I only had the ramcharger a short time before I sold it, but the other ones were bought new and I had them both for over 3 years.
I think this guy hit it right on the head with the intake gasket suggestion. Old Dodge 360's are not the only engine to suffer for this. Even some new ones do too. BTW, a 700 or 750 is way to big for that engine (bigger is not better with carbs) it would run better over all with something around a 500 to 550.
I agree with some of the other replies -- he could very-well be sucking crankcase oil fumes into the intake ports. I suggest that after verifying the compression is good, he start by checking the fit of the manifold to the heads. If it's a b*itch to get the manifold sit low-enough to get the bolts in, you're likely sucking crankcase oil and the manifold should be shaved to fit (or the gaskets are too thick). If the bolt holes in the manifold line-up on-center with the threaded holes in the heads (with gaskets in place and allowing for a small amount of gasket compression), he's fine as far as fit goes.
The other concern are the gaskets themselves. While the OEM cast iron intake manifold will work with the teflon gaskets (FelPro PermaTorque, etc), aluminum intake manifolds have a tendency to warp when those types of gaskets are used. My automotive machinist clued me in about that when my racecar's 340 (Holley Strip Dominator manifold) wouldn't return to idle as quick as it should. He suggested I use paper gaskets. I dunno if they're still made but, my machinist suggests "'75 360 gaskets made by Victor" or if the manifold fits loose, gaskets made by Mr. Gasket (they're thicker). With the paper gaskets, use *a little* sealer (Permatex "Aviation Form-a-gasket", "High-Tack", etc) around the ports. Be sure to not overtorque the bolts (you'll have to guess at the middle bolts). On the other hand, my other
340's OEM cast iron intake manifold is so rigid, I can use whatever gasket I throw at it.
The end seals (under the front and rear of the manifold) in the gasket kits are either soft foam (which weep after time) or cork/rubber, which are a b*itch to compress. Chrysler used roll pins to locate these end seals in place. My machinist discards the roll pins & end seals, and lays down a suitable bead of RTV silicone rubber (after cleaning *all* oil from the gasket and engine block surfaces). Never a leak, and the manifold is easy to get to sit down onto the intake gaskets.
Your friend's carb might be a /tad/ on the large side, but still should be ok. A smaller carb would have somewhat better off-idle throttle response (due to the smaller venturis) at the sacrifice of a little top-end power. I believe that the ideal size carb for a bone-stock hp or slightly warmed
340/360hp would be 600-650 cfm, so you're likely not tooo much over that number.
I can't help you with the 4x4 stuff... no savvy there!
A 700 or 750 should work ok, since they had a Thermoquad on my Roadrunner, and it was an 850, I think. I knew a guy that bought a 73 Charger with a 340 and a 750 Holley on it (Aftermarket). The Holley got cracked by his brother when he got carried away tightening it up, so he borrowed my spare TQ and kickdown linkage (Assembled out of several corpses I got from a junkyard) and it ran a lot better, on and off the track. A TQ that is set up right is unbeatable, for milage, and for power.
My Power Wagon came with a Holley 2 bbl, and I swapped it to the aluminum version of the stock 4 barrel and put an AFB I got cheap on it as soon as the warranty ran out. Once a "flat spot" just off idle was fixed by a local carb guru and his magic drill bit, it ran great, and had great throttle response. I added a cam, lifters and had a friend's uncle clean up the intake and lightly port the heads, and it ran great,
15.10's when it was 110 degrees out, and solidly in the 14's when it was cool out. It was LOUD with the giant pipes and turbo mufflers I had on it.
360 is going to use about 550 CFM at 5500 RPM at most and a stock one will be long past is power range at that RPM. 4 bbl are flow rated at a 1.5 inch pressure drop (2 bbls 3 inches) so even a 500 will flow more than 500 CFM. Smaller carbs give higher mixture veleocites and better reaponce at lower and mid range RPM's. Many use big carbs think thay help but they never bothers to try a smaller carb to see how it would indeed run. I think it is the number os saying that they have a
750 or 850 on there small block that it makes it "bad" when with a smaller carb it would be "badder" most of the time.
ok well if it has anything to do with it.. it does have a mild saturday night special cam in it... but it just started smoking like 3 days ago and hes been driving it every day for the past two weeks with no smoke at all...the smoke now is absolutly rediculous he actually got pulled over by a cop wen he went into down yesterday....... the guy only used it to plow in the winter so it wasnt driven very much, now my freind drives it everyday...i will check compression as soon as i can get the plugs beoke loose they are very rusted into the head they are goin to be a b*tch to get out, what is the ideal compression for a 360,i only really mess with chevy smallblocks....if compression is good then i will pull the manifold and drop a set of gaskets on...should i just get a junkyard cast iron manifold??? thanks alot you guys realy help out alot and i really appreciate it...
Dood, I don't remember that long ago, I am getting old. But I'm pretty sure mine had a 340 in it. The military ones just said Dodge PowerWagon on them and nothing else.
The problem could be intake manifold. If the heads were machined excessive during the rebuild , It will have a hard time sealing. As to 360 id look on the block by the starter. Another way is the thickness of vibration dampner the 318/340 is 1" the 360 is about 1 3/8" The 340 was dropped from production in 72-73. 360's were notirous for low compression. Any HP cam will cause a lower cranking compression 160 psi is in the ideal range. Pratical it is probably
130 psi. I built a custom 360 street motor years age had machine shop cut .050 off the BLOCK for 0 deck height & .040 off the heads & it did require a custom fitted intake manifold
Well, I could be WAY off base here, but this exact thing happened to me many years ago. I had a 65 Chevy Impala SS with a 283 with powerglide tranny. You didn't say if you had an auto tranny, and I have no idea if the Dodge was in any way similar to Chevy's setup BUT..... I was getting clouds of white smoke out of my exhaust....turned out it was a small diaphram valve on the auto tranny, which was hooked up to a vacuum hose on the engine. The diaphram blew and the engine was sucking tranny fluid making immense clouds of white smoke. I know this is a very long shot, but my symptoms were the same except for the engine using oil (the transmission was though!). LarryD
Chrysler transmissions didn't use vacuum modulators, makes them great candidates for super and turbocharging. Good thought though, tranny fluid makes great clouds of white smoke.
Thanks for the info. Like I said, it was a long shot, but I will never forget those billowing clouds of white smoke. A friend and I had just rebuilt that engine and put it back together. We thought we had screwed up big time, and the white smoke really threw us. When we finally had to add trans fluid, the light bulb came on. LarryD
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