Hey all,
I started hearing what to me sounds sort of like a lawnmower/card in the spokes sound when throttling. Oil Level high, changed fairly recently. Has had new set of spark plugs/cables within the year.

If anyone recognizes the sound or has a better description any help would be much appreciated. Can provide more details if needed.

Thanks!

 

Talked to a friend who thinks it might be a problem with the exhaust manifold. Going to take a closer look to see if I can spot any damage once this snow clears up.

 

I agree, sure sounds like an exhaust leak to me. Oil level high? What does this mean exactly? Overfilled? If so, drain out the excess ASAP.

 

Sorry for the confusion, I mean the oil level is closer to the max than the middle of the dipstick markings.

As for the exhaust manifold, I pulled off the shielding to get a better look. I wasn't able to find any holes but the surface has pockmarks and is otherwise in rough shape compared to the other components around it. Next step is ordering a replacement manifold and gasket.

 

Progress update:

I ended up ordering this replacement kit: https://www.newegg.com/atp-101127-ex...82E16888972004 which included gaskets for both the 22R (round) and I believe the 22RE (pear shaped). It came in the other day and I did the removal of the old manifold yesterday.

The removal was pretty straightforward, I watched to get a vague idea of what to do. First I took off the air intake/air filter housing to get more space to work on top of the engine. I then labeled the spark plug lines with tape marked 1-4 and disconnected them. From there I used a 3 inch socket extension to make it easy to get the stud bolts off. All but one of the studs had fused with the nut and required some force to unlodge. I then took out the bolts that connected what the video says is EGR, but the comments say is air injection to the manifold. These came off pretty easy but have separate gaskets that had stuck on pretty fiercely.




The next part was to get under the truck just behind the driver side wheel to remove the bolts holding the manifold to the start of the exhaust pipes. I ended up putting a 10 and 6 inch socket extension together to get at these. The nuts on these came off eventually and the studs remained with the manifold. I then tried to take the manifold off but was not able to get enough clearance to get it off the center stud on the engine and the three studs remaining on the exhaust pipe side. I'm not sure if the video covered this, but there is a bracket that affixes the exhaust pipe to the bottom of the engine that needed to be loosened and slid off. This bracket was pretty crusty and took a bit of convincing to move. After that was off the exhaust pipe was mobile and I was able to get the manifold free.

The exhaust manifold gasket was in pretty rough shape and came apart while I was taking off the exhaust manifold. I took a comparison picture between the new gasket and the old in an attempt to isolate if the failure occurred with the gasket.


From this picture there is a bit of difference in the wearing near the 3rd and 4th cylinders compared to the 1st and 2nd. I do not believe the tear between the 3rd and 4th was related to the removal. Taking a look at the engine side of the 3rd and 4th cylinder it would seem that the gasket had failed leading to these two cylinders to be exposed to each other.


Compared to the other two:


At this time I believe this was the source of the exhaust leak and the noise.

I took a little bit of time to remove some of the carbon build up around the areas that the manifold made difficult to get to. I then took some fine grit sand paper to remove the parts of the old gasket that remained stuck to the engine. I plan to go over it again before I put on the new manifold but here is the first pass:


The replacement kit comes with three studs and since the nuts had fused on 5/6 of the original studs I am currently stuck until I can get replacements. I plugged the holes with some rags and will hopefully get the replacement studs today.

Is there anything I should do while I have this taken off?

Also here is a bonus picture of the old manifold from the inner side. The bit that looks like someone stuck gum to it is some sort of insect lair that turned to dust when I poked it.

 

You're doing a lot of good work here. Just try to get the mating surfaces on the head as clean & flat as possible without going too crazy over it. The metal gasket is a crush gasket & will "take up" any small imperfections on the mating surfaces of both the head & the manifold. I just like to give them all the help I can while I have access to those surfaces, especially those on the head. I usually use a steel wire cup brush on a drill to get all the old stuck-on gasket remains off, then 220 grit sandpaper on a sanding block. I just do enough so that the surface is bright & clean. It comes out pretty smooth.
I also vacuum out all available ports when I'm done sanding.
I've also been known to take a metal ruler to the manifold's mating surfaces to check for any warp-age. It would be interesting to know if you can see any warp on the old manifold near where your leak was.

Also, there is a correct pattern tightening the nuts on the studs. Tighten the nuts starting from the middle of the manifold and work your way out to the outer nuts, alternating sides. I did in stages, starting with 20 foot pounds & then going back & finishing them off at 33 foot pounds.
Exhaust pipe flange nut spec is 28 foot pounds.
After you get the job done and have run several heat cycles (like 50 miles or several separate drives), go back & check the manifold nuts again with a torque wrench. Due to the heat expansion & contraction form cooling off, one or more nuts may loosen up a bit on you. 2 of them did on mine but not much.
Only retorque the nuts on a dead cold engine, not when it's hot.

You're doing great, keep going.