Hey guys,

I am getting back into the hobby and while running my 360 I see its smoking a little on the passenger side exhaust and the valves are making a ton of noise. I had it rebuilt 8 years ago but with my new family I have just took it out sporatically over the years. No time.

I did a leakdown test and the cylinders are leaking at 20% which is low so says my leakdown tester. All the same.

Well it misses bad, car shakes, power is low and I have a lot of valvetrain noise on the passenger side of the engine as well. It used to be a bad tapping lifter but not it sounds like a bag of nickles in there. So I pulled the intake and the cam looks perfect but I will replace the lifters anyway.

I pulled the passenger side head and once cylinder is shiny bright and wet as its burning oil. Cylinder has no damage, slight honing pattern remains from rebuild but not as much as other cylinders. Feels super slick and smooth. I check the valve seals and guides and they are ok.

The thing about this cylinder that's different than the others is that its a sleeve. Are they made of harder steel and thus why its not sealing as well as the rings didnt seat? But I do have real good leakdown test results. Should I pull the piston and ball hone it and intall a soft cast iron ring to get it to seal vs the harder moly that are in the rest of the cylinders?

I just dont want to pull the motor as its a 4 speed in a A body and its a lot of work.

Any suggestions greatly appreciated.

Thanks
sean

hmmm...interesting. I might have the same problem, but my stroked 383 is still making enough power to bring smiles to my face, everything sounds normal, I have good oil pressure, etc. So, I realy don't want to go looking for problems at this point. only problem is that I MIGHT have a slight blow-by issue on one cylinder that does have a sleeve in it.

I would guess that the piston and sleeve are not a match. Wrong size piston. Could also be a broken ring.

If the cylinder passed the leakdown test, it probably isn't a ring seal issue. That would rule out the ring/wall incompatibility question. Looks to me like that cylinder isn't firing. What color is the exhaust valve on that cylinder? If it isn't a shade of brown then you aren't firing. Fuel, fire, and mechanically sound are all required to work. Start checking what you don't have. Good luck.

Check you intake port on that cylinder for oil. It could be a sealing issue for the intake. Oil will show up on the intake valve too.

Thanks guys for the suggestions. It may be the intake gaskets. I wonder if they are not sealing properly due to age and not running the motor much over the years. I'll throw it all back together and see what happens.

When I pulled the intake valve it was a little shiny in the backside. I also noticed that I am getting some oilish carbon buildup in all the other cylinders as well. I also smell gas in the oil for some reason.

When the motor was built, the short block was heavily milled to raise compression and square it up thus the intake had to be cut as well to fit.

Does anyone have any sugestions for intake gaskets as these printoseals may not be thick enough to seal correctly?

Thanks
Sean

Did you use block off plates for the exhaust crossover?

well, if you really are not firing in that cylinder, all that fuel has to go somewhere, and will find its way into your oil pan. that's why your pan smells of gas.

my oil smells of exhaust and is super black after maybe 500 miles of driving.

but then again, It's been about 4 years now since my Cuda's been on the road, and all our other cars are modern, computer controlled EFI crap, so maybe I got spoiled in that short amount of time and am being too critical of my engine!

The top of your piston looks like it's either being washed down by fuel with no combustion or is not getting any fuel at all entering the cylinder. This would definitely contribute to the engine running rough. As stated, you could have an ignition problem caused by a bad spark plug wire, dist. cap, severe vacuum leak, etc. In regard to the excessive noise you are hearing have you checked for zero valve lash on each cylinder?

This may be fishing, but when you put the engine together, all your pistons looked alike/correct. I think the engine bottom is all good. I might suspect you have an intake or an electrical problem. Are your wires on correctly and was the dizzy installed right. That one cylinder could possibly indicate something is out of firing order and by the looks of the other ones and your description, it may be all of them are out.

Could it be a collapsed lifter on that cylinder that's keeping the intake valve from opening and not firing? just a thought.

Rug Trucker id you use block off plates for the exhaust crossover

A: I am running an edelbrock performer and fel pro 1213, no exhaust crossover.

Mopar 4 me: In regard to the excessive noise you are hearing have you checked for zero valve lash on each cylinder?

A: Umm no. I just used the original rocker set with new pushrods but used .030 shims to put it back to what the machine shop said it cut off the deck. I never had valve problems with it before but after I let it sit for 1 year one of them started tapping real bad on startup and it always did after that point, even after an oil change. Now i think its just went bad and maybe its not pumping up anymore to open up a valve.

Cam looks perfect so I’ll put new lifters in there, they are cheap enough.

Klunick: I think the engine bottom is all good. I might suspect you have an intake or an electrical problem. Are your wires on correctly and was the dizzy installed right. That one cylinder could possibly indicate something is out of firing order and by the looks of the other ones and your description, it may be all of them are out.

A: Dist is an aftermarket mopar unit, unchanged from when it ran great. Idles perfectly but under load it runs like crap. I think the plugs are fouled and/or the dist is not pumpin out the amps. I’ll ohm check the wires, and check every spark at the end of the wire. If if no good I’ll put my MSD6 on the car.

I appreciate everyones suggestions. I am going to throw the intake on tonight sans gaskets and see how much clearance I have between it and the heads to make sure the intake wasn’t cut too much leading to an oil intake problem. Then I will pick up new gaskets/plugs and all of that and get it all back together.

This just illustrates why you can’t leave engines sitting for a long time. I was getting real depressed there for a while.

Thanks
Sean

Have you rotated the engine by hand to see what the cylinder wall looks like farther down the hole? I had a problem with a 360 a while ago that drove my crazy.

I had a bad miss and the car was shaking badly. I sprayed water on the headers and the water burned off instantly on all but one cylinder. I did a compression check and it was ok. I put a new plug in that cylinder but nothing changed. I took the valve cover off and installed 2 new lifters on that cylinder and still no improvement. I finally pulled the head and found the problem.

The cylinder looked fine about 1" from the top but after that the cylinder was scored badly. The piston pin had walked out of the rod and was hitting the side of the cylinder. I bet there were two 1/8" gouges out of the cylinder wall were the pin was hitting.

It's probablly a long shot but just thought I would mention it.

Bad valve guide? You said the intake valve had some oil on the back.

Won't water do the same thing?

IMO, 20% leakage is way to much. Do it again and listen for the leak.

A nice tool is the infared thermometer. I bought it when I bought my Cummins to check it. I found one cylinder on my Duster is running 160* so somehing is going on there. It may be valve lash is too tight. I've been running some pretty close lash with the stock cam.

Looks like no fire to that cylinder. Thats why its clean in there. Also explains why it runs like crap. Also explains why you smell gas in your oil. The fuel isnt getting burned. Probably just the spark plug or wire.