Repair-It

Finally back to fixing my own cars.

Since I fixed the belt squeak (tensioner) now I can hear other noises. Like the supercharger. It has a little bearing rattle noise at idle. It's not completely terrible yet, but it really shouldn't be making any noise. So, I decided to change the supercharger oil. Its not clear what the interval is, somewhere between every 30k and never. The car has 124k on it, so its likely that it was never done.

Step #1: find a 3/16" allen wrench. I found mine at the hardware store.
Step #2: remove the fill plug. Normally you'd have to remove the engine cover first, but mine is missing, so problem solved.
Step #3: find a spray bottle. Greater than 8oz is helpful as the capacity is 8oz.

Step #4: take the sprayer out of the bottle and insert it into the fill hole in the supercharger. Put the bottle over the spray nozzle.

Step #5: squirt all the old oil into the bottle.

Step #6: look how dirty it is! The bottle on the left is 8oz of new oil. Compare it to the ~7oz of oil I got out of the supercharger.
Step #7: fill 'er up. I put just about all 8oz of new oil into the supercharger. The "fill line" is the bottom of the threads of the fill plug.

Step #8: reassemble. Then go do burnouts.

I think I'll check the state of the oil next oil change and make a judgement from there on how often to change it. Once a year is probably sufficient. In the mean time, I'll monitor the bearing noise.

The spray bottle is a clever idea to get the old stuff out.

kevm14 wrote:The spray bottle is a clever idea to get the old stuff out.

I learned it on the internet.

Actually, balance shaft rattle is a thing on these engines. From the FSM:

Rattle (Balance Shaft)
Balance shaft rattle sounds like a tinny, chattery rattle or a knocking noise that seems to come from the top rear of the engine. This noise is most pronounced when the engine is hot, and is not affected by engine load. An example would be dirt lodged in the root between two gear teeth. Each time the root between two balance shaft gear teeth meshes with a cam hear tooth, the balance shaft is momentarily forced upward. This pivots the shaft through the front bearing, causing a downward force on the rear bearing that eventually wears the rear bearing, causing a rattle. The following are other factors that contribute to balance shaft bearing rattle:
- A tight link on the timing chain
- Damaged, broken, or dirty teeth on the balance shaft gears
- A worn timing chain tensioner
- Misaligned rear balance shaft bushing

The fix is probably clean the gears at the front of the engine and replace the bushing at the rear of the engine. This requires removing the supercharger and the front timing cover. Not a trivial job. Turns out its fine.

The Eaton M90 supercharger also seems to be famous for various rattles. The easier is the coupler in the input shaft. The harder is the bearings in the rotor pack.

There is a little bit of play in the coupler. I'll probably change it the next time I do a supercharger oil change.

Kevin has a 6 dollar tube of miracle liquid that fixes everything.

billgiacheri wrote:Kevin has a 6 dollar tube of miracle liquid that fixes everything.

He has always been a fan of those.