Color of rod?

-
M

Mike moran

Member
Joined
Jun 3, 2021
Messages
14
Reaction score
5
Location
South Carolina
Pulled the pan on my date code 69 340 and saw this rod a different color. What would cause this . I have never seen this before

IMG_1090.jpeg


IMG_1089.jpeg
 
Perfectly normal and common. The factory coated some with copper. The reason has been hotly debated. To bring one back into weight spec sounds like the best reason to me, but there are other theories.
 
That thing looks brand new (rebuild) inside. Balanced too. May I ask why the pan was removed?
 
Yes, I didn’t like the oil pressure at idle in gear . Put in a new high volume one. Seems better now . Also there was some rtv stuck in the pick up screen
 
Mike moran said:
Yes, I didn’t like the oil pressure at idle in gear . Put in a new high volume one. Seems better now . Also there was some rtv stuck in the pick up screen
Click to expand...
Hopefully you replaced the stock oil pump drive shaft with a hardened one for use with the HV oil pump.
 
High volume pump does not always mean higher pressure. Did you change the spring in the pump for a higher pressure or just change the pump? What was the psi at before? Although I'm glad you're happy with it now.
 
It would have been better to find out why the oil pressure was low. The stock pumps have plenty of reserve capacity, so if pressure is low, there is a problem. Ignoring the symptom might mean the engine will come apart....without your help.
 
The pressure at startup cold was great like 45-50. After fully warmed up it would be down to 15 or so and in gear like 5-10. The oil light would flicker . Not sure yet if cleaning all the junk out of the pickup screen and the new pump did the trick . Thoughts?
 
Mike moran said:
The pressure at startup cold was great like 45-50. After fully warmed up it would be down to 15 or so and in gear like 5-10. The oil light would flicker . Not sure yet if cleaning all the junk out of the pickup screen and the new pump did the trick . Thoughts?
Click to expand...

What some are saying is that low oil pressure is caused by clearances inside the motor being to large and a new or higher volume oil pump is not likely going to solve the actual problem.
It may mask the problem by upping the volume of oil, but does nothing to solve the larger clearances issue.

It would be a good idea to go easy on that motor unless you want to risk exploding it.
 
Mike moran said:
The pressure at startup cold was great like 45-50. After fully warmed up it would be down to 15 or so and in gear like 5-10. The oil light would flicker . Not sure yet if cleaning all the junk out of the pickup screen and the new pump did the trick . Thoughts?
Click to expand...
A clogged pickup screen is more of a problem at higher RPM's than idle. I suspect excess bearing clearance there somewhere is causing the low oil pressure. I'd plastigauge the rod and main bearings while I had that pan off. If they're good, I'd suspect cam bearings.
 
Last edited:
RTV or copper colored rods?
First time I saw those rods and seeing badly worn bearings, as well as alot of junk on the pick up screen, including a couple large chunks of RTV, I thought it was from overheating due to oil starvation.
I'm glad to see that it wasn't and was something common.
 
Last edited:
You must log in or register to reply here.
-

Back
Top