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EQ Magnum head issues?

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  • EQ Magnum head issues?

    I have bought 3 sets of EQ Mopar heads over the last 10 years, 2 of which went onto LA blocks with all the "conversion" parts// the custom pushrods, Magnum engine rockers, valve covers, etc. These were drilled with the LA intake pattern from the factory.
    The 1st set was bought bare, and I fitted it with the best pieces cherry picked off of 5 cracked OEM Magnum heads' valves, springs and retainers, put onto an 83 318 in a 3/4 ton truck. Ground the valves and lapped them in. . the 2nd set was bought "fully dressed" and put onto an LA 360. and into a Ramcharger. Runs fine with no issues. both of these are carb'd applications.
    not sure that means anything but thought I'd mention it
    In both instances, there was a huge noticeable difference, in how the engine they were installed onto, ran.// though to be fair, in both cases they also got "1 step over stock" RV type cams along with the EQ heads......the 318 went from 2bbl to 4 bbl, and the Ramcharger went from that horrible late 80s TBI to a 4 bbl and "Mopar orange box" ignition at the same time, as well.

    now the 3rd set.... actually went onto a Magnum 360 bottom end, otherwise 100% stock rebuild in an 01 Durango. only deviation was an 0.030 overbore and coated hypereuctic pistons. I had plans for a couple of bolt on upgrades once it was broken in// but never got that far.

    A little backstory/ get a beer, some popcorn maybe some no-Doz..... sorry. PLEASE BEAR WITH ME//// ASKING FOR OPINIONS/ASSISTANCE I haven't been here in a while, things have been crazy. and not just with this Durango either.

    I had bought this Durango 5-6 years ago, as a clean transplant from the South, no rust at all, came from Louisiana just a month before I got it. Had the highest miles on it of any vehicle I have ever bought, right off the bat. but it was CLEAN. it was a choice between either this one, or a black 01 a mile from home, with 100k less miles but a 4.7 engine and a "rebuilt" title. I wanted a 5.2/5.9 "or nothing". still haven't owned a 4.7 anything. This Durango was found on CL about 55-60 miles away. was a great vehicle for us from 214k (when I got it) until 250-some K miles when I started getting a chronic code for a cyl 6 misfire. Fought that for most of a year, thought I had it licked, then the bottom end started getting rattley. I had done a thorough tune-up, many sensors, had injectors rebuilt, went thru wiring harness, and more/ everything humanly possible from "outside" the combustion chamber. Until just before the end, the code would come up but engine didn't run like it had any sort of misfire. in the end, "it showed".

    so figuring that my misfire must be internal, (yes I had done a compression test a few times while chasing "external engine" possibilities and it was always 150-ish) but I bought a used 360 from CL and proceeded to tear it apart completely, sent to a machine shop for "the treatment". Complete stock rebuild. Not wanting to get into paying someone to tune a computer for mods, I went back stock.
    I rebuilt the trans at the same time. Brand new cat, muffler, tuneup, O2's, sent starter and alternator in for rebuild at local starter/alternator shop, everything. New fuel pump at same time, even. just because.

    I thought I had my misfire licked, I had sent the computer in to one of those "computer rebuild" places. still had issues. went to a local boneyard and got another 01 Durango 5.9 brain. Start/quit. Start/quit. reminded me of the old ballast resistor issue. It was the damned "security" crap. So I sent the original brain and the junkyard brain back to the computer store. told them that between the 2, please get me 1 good working functional computer, that will run this damn truck. program junkyard brain for my VIN. They did as I asked, "n/c" because I was still having problems. Did what was asked for BOTH brains for free. said both had lifetime warranty, both ran fine on a "test truck" they had out behind the place. Upon the 2nd time sending them in, they apologized profusely for the problems with the original one, and made it known "in no uncertain terms" that the guy who had worked on my original brain "no longer works for us, you won't have issues with either one, very sorry". I guess that whatever had worked loose originally and was re soldered back in, had come loose again. being that the original had been into twice IDK if I can ever trust it again..... they hole sawed a hole in the computer housings and silicone the drilled out piece back in. IDK if that is "normal procedure" or not. I hate computers anyways. the newer you go the more of a PITA they are.

    so I pull the original 360 (still here collecting dust, sitting in the same spot) and put this overhauled 360 in its place with those brand new out of the box EQ heads on it. Fired right up, ran excellent/ not even a lifter tick when it 1st fired/ everything seemed great. I reused the original cam, but brand new OEM roller lifters. Warmed it up good a couple of times in the garage, set distributor SYNC with a scanner, felt good about it.
    The 3rd night, I decided it was time for maiden voyage. I took off, and right off the bat I tried and failed to get the thing to achieve 60MPH. Built up gradual, was acting like it was starving for fuel. Went 2 miles, got it up to maybe 50 max, (all it would do) slowed down, left turn, it stalled. Started right up. Went a mile, tried another left, died again in middle of turn. Would not restart. had gone a total of 3-1/2 miles at this point.
    Called my son for his truck + a tow strap, and while waiting the whole truck was glowing underneath like red neon. the whole exhaust was cherry red. In the end it melted down the new cat, and the front half of the new Magnaflow muffler is now gun barrel blue.
    Got it home, got it running connected the scanner, and don't remember all prameters but one stuck out.... the injector "on time" which should be ~3 to 3.5 milliseconds at idle was running 17.some second mS. yes like 6 times what it should have been..... at this time having no clue where to go next, wondering if it was still the computer, or the injectors that were just rebuilt, flushed, and screens replaced, or what, I went to a U-pull and there was an 01 R/T Durango. Looked like a brand new rebuilt trans, computer was missing, it was a "sale weekend" so I got the whole wiring harness, and that fresh looking trans for a price I could not leave behind (always good to have a spare!)
    I put that other whole engine harness on, and no change. Don't really remember seeing a problem with the original one, but grasping at straws at the time...

    The kicker was going to drop the break in oil out and do the 1st oil change on it, with about 3 hours'' (max) run time. It came out a silver slurry, more silver in the mix it seemed than oil. It needed to come back out.

    In the meantime I parked it, forgot about it. that was Nov. of 2016. The wife absolutely loved that Durango and she has been bugging me since to get back on it---- but I was pissed at it and decided I dint feel like screwing with it no more.... I needed to cool down and quit seeing RED. go at it with a clear mind. Besides I had 2 Dakotas, I pointed at the '96, 4wd one and said "Drive it"....
    well I found a (nother) 136K mile 360 on CL (more than 100K less, than what is on the Durango's body!) for a better than good price. this time, no rebuild.
    the plan was to regasket this (2nd) CL 360 and drop it in. Head off any leaks before it was confined in an engine bay, preventive maintenance sort of things...
    but there was 1 thing... I had that brand new set of EQ heads sitting on that engine that had gone bad on me, sitting in the Durango engine bay, hey, I WANT my $700 new heads on this engine! I pulled the CL engine down to its short block anyways, so I might as well get some good out of that $700 that I'd spent on those things (a small small percentage of what I have in this turd)
    but guess what.... I go to pull the heads off, while that engine is still in place.... WHAT!? #4 exhaust pushrod bent... bad. pulled the valve covers.... #4 exhaust valve stuck wide open. This thing has sat, all this time untouched, to this point I haven't turned the crank a bit from when I pushed it into that side of the garage. W T F!?

    so I pulled the EQ's, and also got a set of stock original heads out of the shed that I have here, a set of heads that is "guaranteed" to be good, off of a buddy's 200k mile 360 that has had synthetic oil from day 1, whose owner removed only because he wanted to build a stroker and wanted aluminum heads..... and these were now "in his way"..... I also still have the ones here that came from the (2nd) CL engine as well.....
    I took the EQs, and the set of heads from the shed (just in case) out to a machine shop that I have worked with several times in the past.....

    I got to the machine shop and the guy recognized them as EQ Mopar magnum heads before I even had a chance to say a word. I carried in the 1st, he went out and got the other one....
    He said " Let me guess... You bought these fully assembled EQ heads, bolted them on your engine and the valves are sticking".... He was dead nuts 100% spot on....
    As it turns out he had a set do the same. He told me he built up a 318 for some kid with a 60s Dart, and thought this would be ideal.... save machine work, time, and not much more than what it would have cost to go thru the original heads from that engine. "No brainer" well in his case he had this customer's 318 on the Dyno (I didn't even know they had a Dyno) and during the 2000 RPM cam break in, the set of these same heads that he had bought for his customer had done the same thing.... said it ruined a piston, ruined the new cam, and then some.....

    So now I am REALLY confused.... did the sticky valves (and now bent/ stuck open #4 exhaust) cause the clogged cat and wide open injectors somehow? OR did the fuel problem cause the valve issue?
    I have let this thing sit for most of 3 years (and out of 3 winters, 2 of which very bad, the only "good" part of this mess) and am determined to solve this issue. I have to get a mechanically "sound" engine back in there to eliminate that part of the issue, down the road I have some shorty headers, 1.7 roller rockers to put on, and then (guys on another Dodge forum that I am actually an admin on are twisting my arm) maybe a computer tune. I'm ready to put an Edelbrock 4bbl and Mopar "orange box" on this thing. I have to get it going and get some miles from it, the only way I am gonna get any of my moneys worth out of it.
    being as how the wife likes it so much (or "did) I don't think that will be an issue.
    When we were regularly driving this Durango, we did pull trailers with it occasionally.... nothing huge, the biggest load was a Wrangler on a borrowed trailer down, and a 80s Bronco II back, 600-ish mile round trip... and I'd have appreciated a bit more grunt.... usually a 6-1/2'X13' with a lawn tractor or 2 on it, sometimes a '78 Apache popup camper.
    When hauling the mowers or the popup, the Durango always handled "like it wasn't even there" these are the most typical loads towed, and only a handful of times a year at that...…
    so, if you made it thru to this point, can you PLEASE offer me some suggestions and insight on this Durango situation? Chicken or egg? Fuel system/computer issue vs sticky valves. This is 1st car/truck engine I have ever experienced valves sticking with, in my life. is there still life left at Mopar Style? I have never ever had this many problems in all of the vehicles I have owned over the years/ let alone all of this on ONE vehicle.... I am not going to be defeated
    Last edited by volaredon; 07-11-2019, 06:31 AM.

  • #2
    nobody knows anything about sticky valves on brand new heads?


    • #3
      I read the entire Post, and I'm at a loss for a logical response. Frankly, I'm not familiar with EQ Heads. Hopefully someone will guy gave an answer.
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      • #4
        ok I cut out some of the extra side story stuff out, that may have been confusing things...that make it any easier to help figure out W T F happened to this thing? . but yeah things have been nuts around here.

        since I came back here and asked for help with this thing, I went onto another (used to be) popular Mopar site and did a search... seems like lots of similar issues with these heads in that same timeframe...
        so would the sticky valves have anything to do with the long injector "on" times? To add to the story, cyls 1,2,3 looked like I bolted the heads on and took them right back off w/o running the thing, cyls 4-8 were as black as coal on the combustion chambers and the plugs....


        • #5
          just heard back from the machine shop... essentially needs a complete valve job in the proverbial sense, all 16 guides "too tight" and need reamed to size, will need at least 1 exh valve (bent) and new guide seals (even though the heads have less than 3 hours of total run time since taken out of the box...… $200+ parts... SOB..... He said I am "lucky" as the last set of these he had, cracked the head around the set didn't/ at least.... gonna have more in the damn heads than in the whole rest of the motor (well almost) for a stock rebuild.

          this has me wondering about the set of EQs that we bought and bolted onto my son's Ramcharger…. he has ~500 miles on that engine, hasn't said anything about any problems/ but he bought "those heads" because he knows how much they woke up the 318 that I put the 1st set of them that I bought.... if his go to $#!T I will never hear the end of it


          • #6
            All throttle , no bottle .


            • #7
              Does anyone here know if sticky valves can cause the computer to add fuel? What is the thinking of computer theory related an issue like this?
              could the computer or injectors still be faulty it has taken me almost 3 years to be able to afford to get back into this thing, I CANNOT afford to destroy another engine. I have rebuilt many engines before this one and a couple since, and never encountered any of the problems as I have on this one job. I have thought about converting to a carb to eliminate the damn computer. As crazy as that sounds


              • #8
                All throttle , no bottle .


                • #9
                  huh.... nobody here has any idea? In a "which came 1st/ chicken or egg" line of thinking I called the outfit that rebuilt the Durango's computer at the time.... supposed to have a lifetime warranty (as long as I own it)
                  but I gotta pay (again) to mail it back to them.... called to pick their brain today and they said they'd recheck things for me, no problem..... still at a loss..... as I again gather parts, and wait on the machine shop.
                  picked up a Cloyes double roller for this CL engine.... its going back. cam sprocket from Taiwan, chain from freaking China.... no way..... not in MY engine.....