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Ticking now comes with misfire at 1200RPM and higher...
#429354
08/05/09 07:35 PM
08/05/09 07:35 PM
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Joined: Sep 2007
Posts: 5,037
hi
sharpie
OP
Moparts Linguist
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OP
Moparts Linguist
Joined: Sep 2007
Posts: 5,037
hi
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I can't think of anything else to do to diagnose. I am literally pulling my hair out, and on the verge of sticking a "For Sale" sign in the back window of the car, all because of the frustration this engine is causing me. This is the roller motor 5.9L Magnum with a .520/.544 Hughes cam, stock lifters/valvetrain/pushrods, RHS heads, and stock valves. It has a very loud ticking. Some days I can pinpoint it to the valvetrain, other times, it sounds like it's coming from the carb, and still other times it sounds like it's coming from the distributor or coil. It moves around. But now, there is another issue: the ticking gets much louder than at idle when at about 1500RPM, and accompanying it is a misfire. The misfire can NOT be heard at idle, though the engine does run rough. This is both with an Edelbrock carb or a Holley carb, both 650s. I guess my carb rebuilds could have been bad, and the misfire sounds kind of random, in the way that it's not always a certain cylinder misfiring (I think?). Since I previous had valvetrain issues, I pulled each valve cover and inspected the pushrods, rockers, and valve springs. All *seem* to check out. I say *seem* because I have no precise measurement tools (nor can I afford any, so don't ask). Summary of the valvetrain: - Torque specs are correct on rocker arm bolts
- Not even a .010" feeler gauge fits between the valve stem and rocker arm
- No cracks, premature wear, or other damage to note on the rocker arms
- Lifters look fine visually and don't move when I press on them with a pushrod (I've heard from multiple sources that this is good, and others say it's bad?)
So I decided to check the plugs and wires. The plugs are wet-fouled a little (gasoline, not oil), but they're fine otherwise. No carbon-fouling. The spark plug wires are all in their correct order, and timing seems to be generally good. At least good enough where it shouldn't run really rough. The only problem I do get is that when I pull #4's spark plug boot, I get a nasty shock. Even when I'm holding the silicone. This has happened on another cylinder too (I forget which one) Summary for ignition system: - spark plugs minimally wet-fouled, but no carbon fouling
- spark plug wires are in the correct order on distributor
- ignition system getting correct voltage and resistance before and after the ballast resistor
- spark plug wires have a tendency to shock
- timing is in the general vicinity
I got a semi-credible tip saying that maybe I have a bent valve on cylinder #5 from the bent pushrod and sheared rocker that I suffered earlier (which has since been fixed). Since I don't own a leakdown test kit, I tried a compression check on three cylinders on a cold engine. I checked #1 and #3 first to get a baseline, and each maxed at about 160psi. I then tested #5, and what do ya know, 160psi the darn thing reads. I suppose I could do a leakdown, but I don't know anyone who could let me borrow the kit and show me how to test it properly. Summary of the cylinders: - compression on #1, #3, and #5 was all reading about 160psi
- piston rings seem to have seated, as there is no oil fouling the plugs
Anyone have any other diagnostic methods to find out where the ticking and misfire are coming from? I fear that soon I will be removing the intake and the head to check out the lifters in more detail, and I really don't have the interest for it. If it comes to that, the car may just be sold or the engine will come out and go back onto a stand and be rebuilt again. I'm unhappy with an automatic transmission behind it anyway. 
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Re: Ticking now comes with misfire at 1200RPM and higher...
[Re: sharpie]
#429355
08/05/09 07:42 PM
08/05/09 07:42 PM
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Joined: Jan 2003
Posts: 4,558
Montana
FuryUs
master
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master
Joined: Jan 2003
Posts: 4,558
Montana
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Quote:
I fear that soon I will be removing the intake and the head to check out the lifters in more detail, and I really don't have the interest for it. If it comes to that, the car may just be sold or the engine will come out and go back onto a stand and be rebuilt again. I'm unhappy with an automatic transmission behind it anyway.
Wow! What happens if the paint gets scratched? Totalled?
If the plugs are wet, change them. Do a compression test on all cylinders. Check the inside of the distributor crack for signs of arcing between terminals--what do you have for an ignition system? And you don't have to remove the heads to pull the lifters.
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Re: Ticking now comes with misfire at 1200RPM and higher...
[Re: sharpie]
#429356
08/05/09 07:51 PM
08/05/09 07:51 PM
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Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
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on the misfire you might pull the wet plugs & dry them w a shot of starting fluid & see if that takes care of the misfire
live every 24 hour block of time like it's your last day on earth
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Re: Ticking now comes with misfire at 1200RPM and higher...
[Re: Neil]
#429363
08/05/09 10:04 PM
08/05/09 10:04 PM
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Joined: Jan 2005
Posts: 12,419
Kalispell Mt.
HotRodDave
I Live Here
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I Live Here
Joined: Jan 2005
Posts: 12,419
Kalispell Mt.
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I second (or third or fourth) the motion to replace the plug wires, they should not be shocking you. Get some fire wires from sunroof GTX.
I would also replace the plugs instead of just cleaning them. I would use good plugs like NGK, don't waste money on platinums and set the gap to .040-.045 the hotter ignition will fire accross a bigger gap and the bigger gap it has to jump the hotter the spark will be and the better it will light the fire and the better it will keep the plug clean.
What is happening is the plug can fire under light load like idle but as soon as it gets more load it fouls out a plug or 2 randomly and it cleans up the next time it gets reved and another one does it. The plug wires are the spot of least resistance when the load gets high so you need to fix that leak. Think of it like a cracked PVC pipe with a spigot on the end, when there is no resistance on the end from the spigot water flows fine, when you start increasing resistance then the crack in the pipe(plug wire) opens up and the water leaks out.
I am not causing global warming, I am just trying to hold off a impending Ice Age!
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Re: Ticking now comes with misfire at 1200RPM and higher...
[Re: Posest]
#429365
08/06/09 12:41 AM
08/06/09 12:41 AM
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Joined: Apr 2007
Posts: 871
WA 98043
thecarfarmer
super stock
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super stock
Joined: Apr 2007
Posts: 871
WA 98043
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FWIW, if a plug wire shocks you, it's failed.
And, it can make a 'tick'.
Do I know for a fact that it's your problem... no. But, I do know it is a problem which should be fixed regardless. And if it doesn't solve the problem, then it's ruled out.
Hope it cures it it.
-Bill
Seduce the attractive, and charm the rest.
******
489 C.I.D., roller cam, aftermarket heads, tunnel ram, stock '54 Dodge rear axle assembly: which of these doesn't belong?
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Re: Ticking now comes with misfire at 1200RPM and higher...
[Re: sharpie]
#429368
08/06/09 07:34 AM
08/06/09 07:34 AM
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Joined: Jan 2003
Posts: 25,200
Upper Midwest
MoparforLife
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 25,200
Upper Midwest
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Quote:
This is the roller motor 5.9L Magnum with a .520/.544 Hughes cam, stock lifters/valvetrain/pushrods, RHS heads, and stock valves.
Not even a .010" feeler gauge fits between the valve stem and rocker arm
For starters with a hydraulic roller lifter motor you should have preload not lash and you should therefore not be able to any feeler gauge between the rocker and valve stem.
Did you use the valve springs that are compatable withthat cam lift and did you check for coil bind. Alos did you check to make sure that you have enough cleanarance between the valve spring retainer and the valve guide and seal so that it does not hit. In boththe above instances you need at least (preferabley more) .060 more travel at full valve lift if you don't you have potential problems and could very well do as you have explained your problem. 
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Re: Ticking now comes with misfire at 1200RPM and higher...
[Re: MoparforLife]
#429370
08/06/09 10:38 AM
08/06/09 10:38 AM
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Joined: Jan 2003
Posts: 16,123
Grand Haven, MI
patrick
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 16,123
Grand Haven, MI
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Quote:
Quote:
This is the roller motor 5.9L Magnum with a .520/.544 Hughes cam, stock lifters/valvetrain/pushrods, RHS heads, and stock valves.
Not even a .010" feeler gauge fits between the valve stem and rocker arm
For starters with a hydraulic roller lifter motor you should have preload not lash and you should therefore not be able to any feeler gauge between the rocker and valve stem.
Did you use the valve springs that are compatable withthat cam lift and did you check for coil bind. Alos did you check to make sure that you have enough cleanarance between the valve spring retainer and the valve guide and seal so that it does not hit. In boththe above instances you need at least (preferabley more) .060 more travel at full valve lift if you don't you have potential problems and could very well do as you have explained your problem.
Don has some good points. when I originally read this thread (especially about the part of the bent pushrod), I thought of maybe coil bind or other hard interference. .544" is A LOT of lift for a magnum style head. my OEM magnum heads had .54" of travel before the seal hit the valve locks, about .57" after the valve job (where I asked to sink the seats a little for more installed height). for your lift, Ideally you'd want at least .58" or more.
I presume you're running hughes 1110 springs? I measured stock springs and they only have about .480" travel before coil bind, and are very soft w/low seat pressure, and wouldn't be able to control an aggressive lobe like the hughes cam has. I am running 1110 springs with 2.2L retainers and magnum locks. I only got 1.60" IH before the valve job (~1.63-1.64" after). The hughes springs coil bind at 1.04, so I had .56" (now .59-.6") travel before coil bind. I'm running a cam with .506" lift. with your cam I'd want AT LEAST .59" travel, preferably .6-.61".
another possibility is the magnum hydraulic lifters don't have a lot of plunger travel, only in the .060" range. maybe with all the parts swapping, head gasket thickness, if the heads or deck were milled, if the valves were sunk, the new cam's base circle, etc, maybe your pushrods are either too long or too short. to short, you might not have enough preload on the cam's base circle, making the ticking noise, which shouldn't affect idle quality, unless the pushrod pops out of the lifter or pushrod cup and bends. Too long, and you may have excessive preload to where it bottoms the plunger and hangs a valve open, or where a valve hangs open if a lifter pumps up.
I lucked out (kinda) with my build, virgin LA318 roller shortblock, uncut (AFAIK) magnum heads, magnum rockers & lifters, and reground LA roller cam (base circle reduced ~.060 to up the lobe lift from ~.26" to .316"), and valves sunk .030" (which raised the height of the valve tip, requiring shorter pushrods) everything worked out that the stock magnum pushrods put my lifter preload right at .020-.030", about mid travel of the plunger. I say I lucked out only kinda, because I had already bought a set of 6.936" pushrods (stock according to my '97 FSM are 6.9-6.916") figuring I'd need longer pushrods with the reduced base circle cam.
and as someone else mentioned about the tick. make sure it's not an exhaust leak. a lot of times they sound like a lifter/valvetrain tick.
another thought on the miss/poor running. double check the reluctor gap in the distributor. it should be .008" measured with a brass feeler guage.
one other thought, when you put this together, did you check valve to piston clearance? .544" is a lot of lift for stock pistons w/o valve reliefs....I wonder if the valve is kissing the piston?
Last edited by patrick; 08/06/09 10:43 AM.
1976 Spinnaker White Plymouth Duster, /6 A833OD
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Re: Ticking now comes with misfire at 1200RPM and higher...
[Re: patrick]
#429371
08/06/09 12:48 PM
08/06/09 12:48 PM
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Joined: Sep 2007
Posts: 5,037
hi
sharpie
OP
Moparts Linguist
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OP
Moparts Linguist
Joined: Sep 2007
Posts: 5,037
hi
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Well I have an update kind of, but some clarification, too. The engine ran fine, sans ticking or misfiring, up until the day I broke that rocker arm bolt. After that, since I switched back to the Holley carb and repaired the rocker arm bolt, it's been acting up.
I am running a combo that, straight from Hughes' collective mouth, "would be fine". I am running 1278 retainers, 1110 springs, and stock locks with the stock lifters, pushrods, rockers, and valves. My valves shouldn't be bottoming out if they're still straight, as not only am I running RHS heads which have a larger dome height than stock, but I am running Speed Pro pistons with four valve reliefs milled into the face.
The minor update was that yesterday I decided to clean up and reinstall the Edelbrock Performer carb I am borrowing. It's a 1405 with non-adjustable floats. I slapped it on and the car not only doesn't idle rough anymore, much of the ticking went away. Even more, the misfire at 1200+RPM is only very slight right now, probably due to the spark plug wires (I'd guess).
What's left of the ticking I can attribute much of it to a leaky exhaust system. I have been a bad boy and never got my exhaust system welded up; it's still clamped together. I figure that I can live with the subtle ticking right now until I get the exhaust welded up, and then I will re-evaluate there. I drove it around yesterday a bit, and I found that it's running easily three times better than it was the day before.
I still have a lot of diagnosis to do on the wires, the misfire, the valvetrain noise which is there but subtle, but I'm feeling a lot better about it. It really helps when you have working parts on your car!
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Re: Ticking now comes with misfire at 1200RPM and higher...
[Re: sharpie]
#429372
08/06/09 03:50 PM
08/06/09 03:50 PM
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Joined: Jul 2004
Posts: 3,809
Arlington, Texas
bobby66
master
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master
Joined: Jul 2004
Posts: 3,809
Arlington, Texas
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Quote:
Well I have an update kind of, but some clarification, too. The engine ran fine, sans ticking or misfiring, up until the day I broke that rocker arm bolt. After that, since I switched back to the Holley carb and repaired the rocker arm bolt, it's been acting up.
I am running a combo that, straight from Hughes' collective mouth, "would be fine". I am running 1278 retainers, 1110 springs, and stock locks with the stock lifters, pushrods, rockers, and valves. My valves shouldn't be bottoming out if they're still straight, as not only am I running RHS heads which have a larger dome height than stock, but I am running Speed Pro pistons with four valve reliefs milled into the face.
The minor update was that yesterday I decided to clean up and reinstall the Edelbrock Performer carb I am borrowing. It's a 1405 with non-adjustable floats. I slapped it on and the car not only doesn't idle rough anymore, much of the ticking went away. Even more, the misfire at 1200+RPM is only very slight right now, probably due to the spark plug wires (I'd guess).
What's left of the ticking I can attribute much of it to a leaky exhaust system. I have been a bad boy and never got my exhaust system welded up; it's still clamped together. I figure that I can live with the subtle ticking right now until I get the exhaust welded up, and then I will re-evaluate there. I drove it around yesterday a bit, and I found that it's running easily three times better than it was the day before.
I still have a lot of diagnosis to do on the wires, the misfire, the valvetrain noise which is there but subtle, but I'm feeling a lot better about it. It really helps when you have working parts on your car!
The floats on that 1405 are adjustable. You bend them to the correct height and drop settings. 
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