Oil consumption and ticking after cam swap?

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Burlapen

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My son and I installed a junkyard 5.9 magnum into a 72 duster last year for the Roadkill 3k hooptie challenge. It was out of a 2001 durango with unknown miles (rear end collision). We finished the install and took off on a 1500 mile road trip the same day. We made it with no issues and the engine ran great other than the distributor loosening up and shifting timing at one point. The event got rained out so we headed back home but then got invited for the filming of the show. I ordered a Hughes 2226-10 cam with matching springs and slammed it in so we could make a bit more power. After doing that, it seems to be burning a considerable amount of oil. It smokes out the pipes under hard accel and through the breathers on decel. It also makes an audible valvetrain ticking in the upper RPMs though this seems to be intermittent. I'm thinking I'll just grab another junkyard 5.9 (they are cheap and plentiful here) and swap the cam over, but I'm wondering what the heck happened. Seems like rings but I don't know why that would happen right after the cam swap and a leakdown test shows all cylinders <25%. Any ideas?
 
i would think it maybe sucking oil around the intake manifold you need to be careful putting them on and bolting it down straight .
 
Thought...
If the cam has more lift than stock. Maybe the tick is valvetrain contact, rockers to valve springs, valves to piston, etc.

New oil smoke... valve seals on a part of the valve stem that was dirty, carbonbuild up etc.

Again just thinking outside the box
 
Thought...
If the cam has more lift than stock. Maybe the tick is valvetrain contact, rockers to valve springs, valves to piston, etc.

New oil smoke... valve seals on a part of the valve stem that was dirty, carbonbuild up etc.

Again just thinking outside the box

Or even just smacking the stem seals, since magnum heads don't have much lift clearance.
 
<<<I see you got the matching springs, good>>>>

intake sealing, but your cam lift exceeds your stock spring height.

"..The valve stem seal and seat to retainer clearance is usually 0.465 to 0.470 max. So cutting down the seat and stem guide boss are required on Magnum heads.."

"...
Another option is to run 0.100" longer valves, but you will need to change pushrod lengths. Rocker geometry will still be safe if you stay below that 0.100 length. If you stay with your stock springs due to wanting low end torque for your Moab or Bear Trail machine, then for a safe setup when choosing a camshaft, keep the lift around 0.450". That gives you 0.060" or more safe bind clearance as the stock spring will bind at 0.520". That is why 1.7 roller rockers work well on stock cams and springs.
  • Stock coil bind 1.125" @ 0 .525"
  • 1.650" @ 85lbs stock
  • 0.480"/1.170" @ 218lbs
So as you can see a 0.480 lift cam list only gives you 0.045" safe clearance from bind on the stock spring. Better to stay safe, use a cam with a mild ramp lobe profile so the stock springs follow it closely and keep the lift around 0.450". Here is the Mopar spring info:
  • 1.425" od 1.055" id
  • 26 grams Mopar retainer
  • 1.640" Installed Height @136lbs
  • 1.150" (0.500" valve lift) @329lbs
  • .990 bind "
 
i would think it maybe sucking oil around the intake manifold you need to be careful putting them on and bolting it down straight .
Good point. It doesn’t seem to run like it has a vacuum leak but definitely a possibility I suppose.
<<<I see you got the matching springs, good>>>>

intake sealing, but your cam lift exceeds your stock spring height.

"..The valve stem seal and seat to retainer clearance is usually 0.465 to 0.470 max. So cutting down the seat and stem guide boss are required on Magnum heads.."

"...
Another option is to run 0.100" longer valves, but you will need to change pushrod lengths. Rocker geometry will still be safe if you stay below that 0.100 length. If you stay with your stock springs due to wanting low end torque for your Moab or Bear Trail machine, then for a safe setup when choosing a camshaft, keep the lift around 0.450". That gives you 0.060" or more safe bind clearance as the stock spring will bind at 0.520". That is why 1.7 roller rockers work well on stock cams and springs.
  • Stock coil bind 1.125" @ 0 .525"
  • 1.650" @ 85lbs stock
  • 0.480"/1.170" @ 218lbs
So as you can see a 0.480 lift cam list only gives you 0.045" safe clearance from bind on the stock spring. Better to stay safe, use a cam with a mild ramp lobe profile so the stock springs follow it closely and keep the lift around 0.450". Here is the Mopar spring info:
  • 1.425" od 1.055" id
  • 26 grams Mopar retainer
  • 1.640" Installed Height @136lbs
  • 1.150" (0.500" valve lift) @329lbs
  • .990 bind "
I guess I should’ve mentioned I got the matching springs and retainers from Hughes. I was told this setup would be good go as far as coil bind and piston to valve on a stock short block.
 
Good point. It doesn’t seem to run like it has a vacuum leak but definitely a possibility I suppose.

I guess I should’ve mentioned I got the matching springs and retainers from Hughes. I was told this setup would be good go as far as coil bind and piston to valve on a stock short block.
how? coil bind I can understand but how about retainer to valve seal? That is a pretty fixed dimension. IE, how much valve stem is showing under retainer? Is it gross lift inches plus some clearance? Im not a magnum guy but if someone can tell us the max lift cam they are running ona stock magnum head, then we could determine what the max lift available to stock valves and guides is.
 
how? coil bind I can understand but how about retainer to valve seal? That is a pretty fixed dimension. IE, how much valve stem is showing under retainer? Is it gross lift inches plus some clearance? Im not a magnum guy but if someone can tell us the max lift cam they are running ona stock magnum head, then we could determine what the max lift available to stock valves and guides is.

I assumed the shape of the bottom side of the retainer is different.
 
On mine, no modifications were performed at all except installation of Hughes cam SER1418ALM-10 and their retainers and locks. I used light checking springs and a set of dummy lifters I plugged to make into solids, and found right at .550" test lift the intake retainers contacted the factory style valve stem seals. The exhaust retainer contacted the seal at .540" test lift. I had my guides cut down for clearance.
Others have said they successfully used a bigger Hughes cam with same retainers and had no failures, but did not check clearances.
When I measured mine, the retainer to guide clearance was an issue way before valve to piston clearance, with stock pistons.
 
On mine, no modifications were performed at all except installation of Hughes cam SER1418ALM-10 and their retainers and locks. I used light checking springs and a set of dummy lifters I plugged to make into solids, and found right at .550" test lift the intake retainers contacted the factory style valve stem seals. The exhaust retainer contacted the seal at .540" test lift. I had my guides cut down for clearance.
Others have said they successfully used a bigger Hughes cam with same retainers and had no failures, but did not check clearances.
When I measured mine, the retainer to guide clearance was an issue way before valve to piston clearance, with stock pistons.

Thanks for the real world info Bobzilla. Could be some clearance issues there then. I didn't check anything as I was assembling it at 3:00am and we had to leave at 5:30am :)

I'm glad I did the magnum swap however I'm finding the budget/power deal only goes so far. Even EQ heads are pretty expensive compared to aftermarket heads for non-magnum stuff. Tough to get a good pair of budget heads for the magnum for sure.
 
on umbrella seals, can you grind the valve guides down manually?
 
Magnum engines use positive seals, not umbrella seals, but you can definitely cut or grind the guides down using a number of different methods with varying results. Just another modification, and end result will be as good as the effort put in.
On Magnums, you need a cutter because of the two different diameters that need to remain intact. One is the small diameter that the positive seal goes on, and the one below it is larger and used to position the bottom of the spring.
 
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