Rear Main Cap Drain Tube Question:
- Thread starter JBR
- Start date
Dave in MN
Well-known member
Lots of oil on the floor!
If this plug is missing, the fluctuations in crankcase pressure or any blow-by would slow the oil from flowing back to the bottom of the tube which should be immersed in the pan oil. This probable venting through the drain passage could/would cause oil to be pushed out the rear seal area. Had a friend missing one on his engine...leaked! He installed the missing plug...stopped!
Good day!
Dave in MN
If this plug is missing, the fluctuations in crankcase pressure or any blow-by would slow the oil from flowing back to the bottom of the tube which should be immersed in the pan oil. This probable venting through the drain passage could/would cause oil to be pushed out the rear seal area. Had a friend missing one on his engine...leaked! He installed the missing plug...stopped!
Good day!
Dave in MN
JBR
Senior Member
Thanks Dave for your reply.
I just completed an overhaul because of a cracked center main bearing. The mains were poured and bored. I got the engine back together and she started right up. She ran so nice.
I have been driving it fairly easy at various speeds trying to break the motor in. It has been running great and I am really pleased.
On Tuesday, I left home and put about 60 miles on the car. I stopped for some gas and noticed about a 3" circle of oil under the car. I wasn't too concerned and started on my way.
When I got home, I ran the car in the garage, parked, and looked under the car to check for leaks. There was a puddle about 15" in diameter under the car in about 15 seconds. Something didn't seem right.
After talking with a buddy I pulled the pan. The only thing I could even see that could have been wrong was the plug missing. I only found that because I was checking to see if the drain tube was plugged and looked at another cap with the plug still in place.
I got plug from another cap and tapped it in place. I than spread some JB Weld on it to keep it in. I put the pan back and took about a five mile drive. I parked it in the garage and put some newspaper under it. After 2 hours of sitting I only had 2 drops of oil on the paper, and some of that may have been from before.
So, the operation seems to have been a success.
Thanks for your help.
Jon
Gees, I'm getting as bad ad Marshall.
I just completed an overhaul because of a cracked center main bearing. The mains were poured and bored. I got the engine back together and she started right up. She ran so nice.
I have been driving it fairly easy at various speeds trying to break the motor in. It has been running great and I am really pleased.
On Tuesday, I left home and put about 60 miles on the car. I stopped for some gas and noticed about a 3" circle of oil under the car. I wasn't too concerned and started on my way.
When I got home, I ran the car in the garage, parked, and looked under the car to check for leaks. There was a puddle about 15" in diameter under the car in about 15 seconds. Something didn't seem right.
After talking with a buddy I pulled the pan. The only thing I could even see that could have been wrong was the plug missing. I only found that because I was checking to see if the drain tube was plugged and looked at another cap with the plug still in place.
I got plug from another cap and tapped it in place. I than spread some JB Weld on it to keep it in. I put the pan back and took about a five mile drive. I parked it in the garage and put some newspaper under it. After 2 hours of sitting I only had 2 drops of oil on the paper, and some of that may have been from before.
So, the operation seems to have been a success.
Thanks for your help. Jon
Gees, I'm getting as bad ad Marshall.
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