Valve cover caps milky after 30 min on hose - condensation or something else?
06-27-2011, 10:13 AM
#1
Valve cover caps milky after 30 min on hose - condensation or something else?
Background - brand new engine, stock iron heads, Performer RPM intake, FelPro #1211 intake gaskets, Lightning headers. Stock cooling system with factory circ pump and T-stat housing. Heads have had maybe .030 milled off of them, and block was decked about .006 to square things up. I told the engine builder that I did not want any more material taken off the heads than would allow me to safely run an intake that had not been milled.
I had a few issues early on getting water flow - replaced impeller, but I think the issue was actually the suction hose leaking air at the transom inlet. Fixed that, and am now getting a steady flow of water out the exhaust. I ran it on the hose for about 15 minutes last night, air temp was about 85*, somewhat humid. After it ran for a while, I noticed a lot of condensation building up in the clear vinyl tubes I have running from the VC breathers up to the flame arrestor. Uh oh. I shut it down and pulled both filler caps off the valve covers, and noticed some milky looking residue on them. Pulled the stick, and level was still the same, and oil looked crystal clear. I may have seen just the faintest coating of milky residue on the top of the stick, but I could not be sure. Ran my fingers along the inside tops of the valve covers, and got maybe a little bit of residue. Did not see anything on top of the heads.
Does the amount of "junk" on the filler cap in the picture look too heavy for condensation? I did not check the previous 3 or 4 times I ran it. The engine has a total of maybe 30 minutes run time on it, all on the hose.
I am tempted to just drop it in the water and run it a little bit to see if it gets better or worse, but I am worried about milkshaking a brand new engine. Should I consider pressure testing the cooling system before I proceed?
I had a few issues early on getting water flow - replaced impeller, but I think the issue was actually the suction hose leaking air at the transom inlet. Fixed that, and am now getting a steady flow of water out the exhaust. I ran it on the hose for about 15 minutes last night, air temp was about 85*, somewhat humid. After it ran for a while, I noticed a lot of condensation building up in the clear vinyl tubes I have running from the VC breathers up to the flame arrestor. Uh oh. I shut it down and pulled both filler caps off the valve covers, and noticed some milky looking residue on them. Pulled the stick, and level was still the same, and oil looked crystal clear. I may have seen just the faintest coating of milky residue on the top of the stick, but I could not be sure. Ran my fingers along the inside tops of the valve covers, and got maybe a little bit of residue. Did not see anything on top of the heads.
Does the amount of "junk" on the filler cap in the picture look too heavy for condensation? I did not check the previous 3 or 4 times I ran it. The engine has a total of maybe 30 minutes run time on it, all on the hose.
I am tempted to just drop it in the water and run it a little bit to see if it gets better or worse, but I am worried about milkshaking a brand new engine. Should I consider pressure testing the cooling system before I proceed?
06-27-2011, 02:41 PM
#6
Registered
That is a lot of moisture, I run my boat in really cold water (34F) and have never seen anything like that. How much has this motor been run since you put it together? I've run mine on a hose in the spring and my water comes from a deep artesian spring and I have never seen anything like what you have. I would run a pressure test, cheaper than wasting a good motor.
06-27-2011, 02:56 PM
#7
That is a lot of moisture, I run my boat in really cold water (34F) and have never seen anything like that. How much has this motor been run since you put it together? I've run mine on a hose in the spring and my water comes from a deep artesian spring and I have never seen anything like what you have. I would run a pressure test, cheaper than wasting a good motor.
06-27-2011, 03:58 PM
#8
I feel you are fine. But that is just my input, i see this all the time from Dodge cars and trucks to my 600 Merlin real bad with Aluim heads too both of my buddys Baja same thing all motors running great to this day..............
Skydog P.S. Just keep a eye on oil level and you will be fine. Been there done that.........
Skydog P.S. Just keep a eye on oil level and you will be fine. Been there done that.........
Last edited by skydog; 06-27-2011 at 04:01 PM.
06-27-2011, 09:55 PM
#9
Well, the verdict is in, and it looks like.... condensation!
You nailed it, SkyDog. Took it out to the river and dunked it - actually ran it on the trailer for 5 minutes or so to make sure water was coming out the pipes and it was running OK. I had a temp gun, and the intake manifold was only getting up to around 71*. Water temp was around the same. I was seeing some condensation in the tubes at this point. Backed it off the trailer and ran it for a while. Stopped several times to check dipstick and VC caps. Dipstick stayed crystal clear - in fact, this oil is so clear that it is hard to see on the dipstick. Caps still showed a very tiny bit of white stuff, but nothing to be concerned about. Ran it easy until it started to get dark, then back on the trailer. I feel much better about this rig now! Never got above 3600 RPM, but this motor has a ton of torque! Getting up on plane is effortless. I have a few small issues to work through, like installing the oil temp gauge and water pressure gauge, and I'll run it again this weekend.
You nailed it, SkyDog. Took it out to the river and dunked it - actually ran it on the trailer for 5 minutes or so to make sure water was coming out the pipes and it was running OK. I had a temp gun, and the intake manifold was only getting up to around 71*. Water temp was around the same. I was seeing some condensation in the tubes at this point. Backed it off the trailer and ran it for a while. Stopped several times to check dipstick and VC caps. Dipstick stayed crystal clear - in fact, this oil is so clear that it is hard to see on the dipstick. Caps still showed a very tiny bit of white stuff, but nothing to be concerned about. Ran it easy until it started to get dark, then back on the trailer. I feel much better about this rig now! Never got above 3600 RPM, but this motor has a ton of torque! Getting up on plane is effortless. I have a few small issues to work through, like installing the oil temp gauge and water pressure gauge, and I'll run it again this weekend.
