Hello,

I'm new to the forum and looking for advice. I recently had a balance shaft seal ejected from the engine and into the timing belt cover. Luckily I was able to pull over and shut the engine off prior to causing damage, oil light was on for maybe 4 seconds before the engine was shut off.

I took the car to a local shop who I've used before. They got the car all fixed up and completed a timing belt service as everything was coated in oil. I picked up the car and it drove perfectly fine, however I noticed a vibration/hum that starts around 2,500 RPM and seems pretty noticeable thru the remainder of the rev range. The vibration/buzz can be felt all over the car, and I can notice the rear view mirror vibrates like an electric toothbrush.

A week after the work, I took the car back to the shop and they mentioned that I may never had noticed the vibration prior to the fix. They said everything was fine. I understand they may not want to pull it all back apart to inspect for a "vibration".... However from what I've read on here, and other areas is that the rear balance shaft may cause vibration if not timed properly. Makes sense. I've also seen that the rear balance shaft is a 3/1 in terms of the shaft rotation, and that there's an inspection port that can be used insert a screwdriver/bolt to verify the balance shaft is properly timed. I'm thinking this may be the issue.

All of that to ask, if the rear balance shaft is not timed would the result be the "electric toothbrush" type vibration I'm feeling or would this vibration be caused by something else? I'm going to take it back to the shop, but I'd like to have an idea of what may be causing this in order to help them troubleshoot.

Some additional info if it helps.

2000 Honda Accord SE
2.3 Vtec
Automatic Transmission
150,000 miles
Newer motor mounts
New Tires, recently balanced at 148,000 miles
The shop has worked on the car in the past with no problems.
Work completed during the last repair:
- Balance shaft seals replaced
- Crankshaft seals replaced
- Camshaft seals replaced
- Timing Belt replaced
- Water Pump replaced

I'd appreciate any insights.

Take Care

 

Motor mounts could cause a vibration, but it looks like they were replaced. Were the mounts replaced before the timing belt job? If yes, then I'd ask the shop to check if the balance shafts are in time. Also, the timing belt tensioner pulley needs to be installed on a post to pivot properly. Both can be checked by pulling the timing belt covers.

 

Sounds to me that if this particular noise came after t-belt replacement, shop got rear shaft misaligned and or
the tensioner not positioned properly in the alignment pin

 

All,

Thanks for replying, it helped troubleshoot. I ended up taking a look at the position of the balance shaft, it was correct. I was confused, but just figured my car would vibrate for life. A week ago it came to a head, the front balance shaft seized. The belt was kicked off and it made a terrible noise.

The shop I took it too before worked with me and warrantied the work. We decided on a balance shaft "delete" and remove the balance shaft belt. The car runs GREAT! The vibration is completely gone and it feels back to normal. I don't suppose this will be a big problem as there's virtually no buzzing anymore.

Again, thanks again for taking a look and helping with suggestions.

Have a great day everyone