Ticking now comes with misfire at 1200RPM and higher...

Posted By: sharpie

Ticking now comes with misfire at 1200RPM and higher... - 08/05/09 11:35 PM

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.

Posted By: FuryUs

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/05/09 11:42 PM

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.

Posted By: RapidRobert

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/05/09 11:51 PM

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

Posted By: sharpie

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/05/09 11:54 PM

I have a Mopar Performance ignition system. MP distributor, orange box, ballast. Pertronix epoxy-filled Flamethrower coil. BWD spark plug wires from O'Reilly.

The plugs are now fine. All have been cleaned and lightly scotch-brited on the metal areas so it will be conducive to a spark situation. By fouling, I meant there were two drops of gasoline on them or so.

As for the lifters, you can't get them out unless the head is off - they're too tall otherwise.

Posted By: buildanother

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 12:07 AM

Is the retainer plate for sure on front of block, to hold cam in place?

Posted By: sharpie

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 12:10 AM

Yes, it is there. I put it there myself even and torqued them down with locktight

Posted By: Neil

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 12:11 AM

Bad plug wire on number four since you say it's shocking you when you touch it? Start it up when it's pitch black out and look for arcing coming out of the plug wires, particularly wire #4. Got another plug wire you can try out? If not then move the suspect wire to the other side of the engine and see if the miss doesn't follow it around.

A wire with a hole in the outer sleeve will create a missfire condition since the current is going to your header tube, valve cover, or whatever else happens to be be conductive that's close to the hole. You can read the resistance on spark plug wires with a meter too if you have one.

BTW you can start the car with one wire off at a time and not hurt anything, beats shocking yourself.

If you had a bent valve problem your compression test would have shown that right away with a big fat zero on the guage - don't think that's the issue here.

Carburetors can't really cause a missfire unless it's a dual plane and one jet is plugged. If that were the case the car would run so rough you'd have a hard time even getting it to idle.

Posted By: sharpie

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 12:16 AM

I suppose it could be the carb problem then. Until something goes right (don't know what), it does in fact have a hard time idling. And it is a dual-plane Edelbrock air-gap on top.

Posted By: Neil

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 12:20 AM

Your carburetors(s) can't cause a single cylinder to act up at any rpm range. Go after the plug wires first and see what you have going on there.

Posted By: HotRodDave

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 02:04 AM

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.

Posted By: Posest

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 04:10 AM

I agree with Dave. Once a plug is fouled throw it away. I went against my own advice and re used a set in my Dakota. Used them to plug the cylinders when going in with the engine. Had a slight miss at 2K and up. Put new plugs in and slight miss is gone. It was just a slight sputter but still there and bothering me. The open hood at night trick works real well. I have found several bad wires this way.

Posted By: thecarfarmer

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 04:41 AM

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

Posted By: enelson

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 05:43 AM

sounds like you should do plug wires first. Get good ones so you can have em a while. I think it cost me 50-90$ for pliers and a make-my-own set of msd red ?mm set a few years ago and they've served me well and left me with tons of extra parts to fix anything I need to.

I'm in sacramento, and have a spare msd 6a if you wanna swap ignition systems, but I doubt it's a box. Most likely parts and shocks are never good.

Hit me up on PM and I'd be happy to help if I'm not bumping the thread.

Posted By: enelson

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 05:45 AM

Oh yea, good luck!

And check those header gaskets with a stethescope or broomstick, you might be hearing them accompanied by misfires

Posted By: MoparforLife

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 11:34 AM

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.

Posted By: HotRodDave

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 02:07 PM

I caught that too about the valve lash, just forgot to type it

Posted By: patrick

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 02:38 PM

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?

Posted By: sharpie

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 04:48 PM

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!

Posted By: bobby66

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 07:50 PM

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.

Posted By: sharpie

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 08:16 PM

Yeah, but assuming they've been set up correctly either by Edelbrock or the previous owner, it's one less thing I can screw up!

Posted By: Neil

Re: Ticking now comes with misfire at 1200RPM and higher... - 08/06/09 08:40 PM

I have owned several of the edelbrock carbs and they are never set up right from the factory. I always take them apart and make the neccessary corrections before attempting to use them. A few have been close to being right, and some have been off by a mile.

The floats are easy to set up, but it takes a few tries to get them set in the right spot(s). Keep in mind that there are two adjustments to be made per float.

It's worth the effort though since it makes the engine run all the better, the engine won't want to die when you come to a fast stop or make a sudden sharp turn, and you probably will never have to mess with them again after they are set.