drsab2000

It's been a while since I've posted because the car was running great. The car has developed an oil leak in the front of the engine. The oil is dripping from the vent hole in the lower cover. It was time for a timing belt change (195K) so I dove in. After removing the upper and lower covers, there was not a lot of oil around the crank and cam seals but there was oil aroung the dipstick tube. There was no oil on the belt or sprokets. The face of the head and block has oil on it. So I changed the crank seal, cam seal, dipstick tube o-ring, valve cover gasket, water pump, idler and all the belts. Drove the car about 30 miles, put cardboard under it and an hour later, same oil leak. The oil pan gasket was changed about 3 years ago when I did the rear crank seal. What did I miss? Is it possible it's the head gasket? Car runs great. No oil in antifreeze, no antifreeze in the oil. Plugs look great. 1999 Civic EX needs help! Thanks in advance.

P.S. I hate that crank pulley bolt.

Former User

<p>The oil pump is another common site for an oil leak behind the lower cover. &nbsp;Did you inspect that area with the crank pulley off?</p><p>Removing the oil pump, replacing the O-ring, and forming a new gasket with HondBond fixed my leak.</p>

drsab2000

Thanks Ron. I did remove the pulley and cover and inspected that area. There was signs of oil but I couldn't pin point the source. I found info on this site regarding the oil pump o-ring. I did not change that one. If I have to take this apart again, I want to get it right. How likely is this a head gasket oil leak behind the cover? Is there oil passing throught the block into the head in this area? I don't see any signs of oil around the head-to-block seam outside the cover. Thanks again.

TomCat39

This is my secret weapon for crank pulley bolts.

If 730 ft-lbs of torque can't break it free, then something is seriously wrong.

The other challenge was finding a 3/4" drive 17mm socket which I just got recently.

Torque Multiplier | Princess Auto



Looks like this:
https://honda-tech.com/general-discu.../#post50461115

Former User

<p></p><p>It's possible, just not as common as the oil pan gasket, crank and cam seals, and oil pump for a leak from behind the lower cover.</p>

drsab2000

To Tomcat: Thanks for the info on the 3/4 inch drive solution. I was able to loosen it with a 1/2 inch drive extension attached to a breaker bar and the 5 foot handle from my pump jack as my cheater. WOW when it breaks, look out.

To RonJ: Your advise has helped me in the past (rear crank seal) so I hope your "Honda Zen" is correct about the head gasket and it's just the oil pump o-ring.

Thanks for your help again!

Former User

<p></p><p>The oil pump O-ring itself would not cause the oil leak. &nbsp;The leak generally is from the HondaBond gasket you create after you carefully scrape off the old gasket material. &nbsp;Buy a small tube of&nbsp;HondaBond from Honda, and consult your service manual. &nbsp;While the oil pump is off, replace the O-ring and the gasket for the oil strainer.</p>

TomCat39

Another little tip about the hondabond/flange sealant bit you might find helpful.

Besides scraping off the old material, cleaning the areas (block and pump surfaces) with non chlorinated brake cleaner will remove any oil residue and evaporate residue free.

This procedure leaves the mating surfaces clean and fully prepped for the hondabond/flange sealant to adhere to the metal.