Archon 10 Report post Posted February 25, 2012 Ok so when the car is cold it has no problems. When it heats up the oil pressure drops significantly and I start to get a slight knock. I know the rear main needs to be replaced but would that fix my problem? Also what would be a reasonable price for a mechanic to charge to replace the rear main? Thanks. Quote Share this post Link to post Share on other sites
Archon 10 Report post Posted February 25, 2012 Ok so when the car is cold it has no problems. When it heats up the oil pressure drops significantly and I start to get a slight knock. I know the rear main needs to be replaced but would that fix my problem? Also what would be a reasonable price for a mechanic to charge to replace the rear main? Thanks. Quote Share this post Link to post Share on other sites
jkskinsfan 19 Report post Posted February 26, 2012 What weight Oil are you using? Quote Share this post Link to post Share on other sites
jkskinsfan 19 Report post Posted February 26, 2012 What weight Oil are you using? Quote Share this post Link to post Share on other sites
Flanders 46 Report post Posted February 26, 2012 My rear main seal was a piece of rope. I had to take the engine out (to lift the crank up) to get it out! If you have a 2-piece rear main then it can be done by dropping the oil pan and rear main only. So, I'd say it's tough to give an accurate guess on labour! Plus, I'd say a leaky rear main seal isn't going to cause the pressure drop that you're seeing. As asked above, what weight oil are you using? Quote Share this post Link to post Share on other sites
Flanders 46 Report post Posted February 26, 2012 My rear main seal was a piece of rope. I had to take the engine out (to lift the crank up) to get it out! If you have a 2-piece rear main then it can be done by dropping the oil pan and rear main only. So, I'd say it's tough to give an accurate guess on labour! Plus, I'd say a leaky rear main seal isn't going to cause the pressure drop that you're seeing. As asked above, what weight oil are you using? Quote Share this post Link to post Share on other sites
1969mustang 10 Report post Posted February 26, 2012 Sounds like your oil is way to thin, the bearing clearances are wrong, or the engine is worn out. What is your oil pressure cold? Whats it go down to when the engine warms up? Quote Share this post Link to post Share on other sites
1969mustang 10 Report post Posted February 26, 2012 Sounds like your oil is way to thin, the bearing clearances are wrong, or the engine is worn out. What is your oil pressure cold? Whats it go down to when the engine warms up? Quote Share this post Link to post Share on other sites
Lemon Owner 11 Report post Posted February 27, 2012 Rear main seal will not cause low pressure. How many miles on the engine? Quote Share this post Link to post Share on other sites
Lemon Owner 11 Report post Posted February 27, 2012 Rear main seal will not cause low pressure. How many miles on the engine? Quote Share this post Link to post Share on other sites
stangnet33 88 Report post Posted February 27, 2012 For starters stick a mechanical oil pressure gauge on it to find out what the oil pressure is from a cold start up to being warmed up...... Quote Share this post Link to post Share on other sites
stangnet33 88 Report post Posted February 27, 2012 For starters stick a mechanical oil pressure gauge on it to find out what the oil pressure is from a cold start up to being warmed up...... Quote Share this post Link to post Share on other sites
