Timing Chain Cover Oil Leak - Toyota Matrix

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Nov 25, 2020
Messages
13
hello:

I have a 2005 Toyota Matrix, which has a slow leak coming from the timing chain cover

leaking at the rear side, at the 3-way junction where the head, block, and timing chain cover meet up... this also happens to be where the timing chain tensioner is located (a known leak point, but this has already been fixed and is not leaking)

the leak is modest, getting approx. 2-3 drops per week on garage floor... oil level does NOT drop noticeably between oil changes (and I just went 10,000 miles, oops)

VEHICLE
Model: 2005 Matrix, base model, 2WD (similar to Corolla)
Engine: 1.8L 1ZZ-FE R
Mileage: 51,000 miles / 85,000 km

NOTES:
  • currently using 5W-30 Pennzoil Synthetic Platinum (not HM version, not Ultra)
  • used conventional oil up until 35,000 miles / 59,000 kms
  • timing chain cover is sealed at the factory using RTV, not a gasket
  • moderate winter climate (Vancouver Island, Canada)... rarely much below 32F / 0C
  • this engine is known to have oil passageway clogging issues, hence my switching to synthetic oil (after I purchased the car)
  • the leak area is located higher up so does not sit "underwater" at rest... also, the timing cover chamber is hollow and not under full liquid oil pressure

clearly, the gasket has failed, and thus some oil is able to escape

sure, the proper fix is to renew the gasket seal(s), but this is a MAJOR job requiring engine removal, and I can't justify spending $2,000 to fix... plus won't risk disturbing a perfectly good but 15-year-old engine, possibly introducing new problems

POSSIBLE SOLUTIONS

1. switch to a different oil... eg. non-synthetic, non-synthetic HM, synthetic HM ???
2. add some sort of "stop leak" product to the oil
3. replace PCV valve (to ensure excess pressure is not occurring inside timing cover chamber due to sticky valve)
4. ensure oil level is not too high and between dots on dipstick (to ensure excess pressure is not occurring inside timing cover chamber)
5. tighten cover bolts in that area
6. apply some sort of sealer ON THE OUTSIDE of the leaky area... for example, "Permatex Spray Sealant Leak Repair #82099" (product info)

regarding #6: having a "magic spray" solution sounds very nice, but apparently surface prep is critical for success (complete degreasing), but this is a fairly hard to access area, so cleaning and application could be very difficult... also, the spray is very watery, so the permanent overspray mess might be brutal

PHOTO GALLERY HERE

I would really appreciate hearing any comments on my possible solutions, tips, experiences, or suggestions

thank you!
 
Try M1 HM 5w30. I might try something regarding solution #6 as if oil can leak out then air,dirt, moisture can get in. Thickest I would go is M1 0W40 but I would try making sure PCV valve is working and getting that vehicle up to temperature regularly to burnoff moisture will help significantly too. Was a Canucks fan when the Sedins and Kessler were there.
 
As to PimTac's question, the original post seems inconsistent. Sealant only, or failed gasket?
I once thought I got your #6 to work, but that was in a more accessible area on a transmission.
 
As to PimTac's question, the original post seems inconsistent. Sealant only, or failed gasket?
I once thought I got your #6 to work, but that was in a more accessible area on a transmission.


I’m not familiar with this particular engine but many use a sealant in that area versus a gasket. In that case a HM oil would be of no help.
 
here's a photo, just to make sure it's saved with this thread:
DSC00443.JPG
 
As to PimTac's question, the original post seems inconsistent. Sealant only, or failed gasket?
I once thought I got your #6 to work, but that was in a more accessible area on a transmission.
clarification to my OP... I meant to say: "clearly, the gasket sealant has failed, and thus some oil is able to escape..."
 
If tightening the bolts doesn't work, my solution was to buy a large aluminum tray at autozone and place it in the garage under the engine and monitor the situation. You could go another 100k miles without any worsening of the leak.
 
It uses sealant. If you are able to reach the area where it’s dripping get some Black RTV the oil resistant one and put it on there then tighten down the bolts some not too tight but snug.
This, and spray down the area first with brake clean, let it dry, apply the RTV, and let that set overnight before driving the vehicle.
I would revert to a HM conventional 10W-30 as well if it was my car.
More frequent oil changes are more effective in preventing blockages vs using synthetic in your climate imo.
 
That has been an issue for other older Toyota models . I think it was related to the sealant or poor sealing from the factory . A removal of the cover and resealing solved the issue . The new sealant was black , factory was white . Your issue may be different . May want to use a dye . Clean area thoroughly before checking . Good luck .
 
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additional info:

before the photos were taken, I had a mechanic spray all oily areas with brake cleaner, then I drove car for a week... source of leak appears to be coming from where I've indicated (ie., not oil pan, not crank pulley)
 
Give it a good cleaning if able . I use window cleaner ( ammonia ) . Does a good job of dissolving oils / lubricants . Use it for messy O.C.s and cleaning pail used for draining oil .
 
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