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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Apr 2009 Posts: 121 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2009 Posts: 121 | hey there, took my 49 6400 with a 1962 261 out for its first run on the big road today and everything worked great....except for when i got back, i pulled the valve cover cap and found some milky slimy stuff.so im getting water in my oil.where should i start?cracked head,blown head gasket?Just wanna get this taken care of so i can get back on the road! thanks, Dan | | | | | Joined: Feb 2004 Posts: 29,875 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,875 | What does the oil on the dipstick look like? It's not uncommon for condensation to form inside the valve cover, and if you don't drive far enough to get the whole engine warmed up well, that slimy mess in the valve cover will stay there. A serious coolant leak will turn the crankcase oil milky, and make the level show above full on the dipstick. Give it at least a 20-mile drive as close to highway speed as is safe, and see if some of the slime goes away. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
| | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 | Dan,
When did you last change the oil/filter?
| | | | | Joined: Apr 2009 Posts: 121 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2009 Posts: 121 | the oil/filter is new, and the dipstick shows clean oil.i did drive it enough today to get it fully warmed up, but maybe that wasnt enogh to get the slime to go away? im driving it to town on wednesday to get the exhaust done.when i get there, ill check to see if the slime goes away.if its still there under the valve cover, what should i do.should i pop the whole head off to look for cracks or a blown head gasket? Thanks, Dan | | | | | Joined: Aug 2009 Posts: 295 Shop Shark | | Shop Shark Joined: Aug 2009 Posts: 295 | I think this is just condensation in the crank case. Very common in engines without Pos Crankcase Ventilation PCV. If you are not getting the engine warm ie short trip driving it is worse. Only solution is longer trips, cardboard on radiator, more frequent oil change.
Instead of doing hunt n peck as far as leakage in engine 1. Compression test 2. Pressurize coolant system - if hold pressure for 15 minute no problem. Do NOT go over say 10 maybe 15 psi.
Dan Bentler | | | | | Joined: Apr 2009 Posts: 121 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2009 Posts: 121 | welll today i found water on my dipstick.what should i do first? Danny | | | | | Joined: Dec 2008 Posts: 319 Shop Shark | | Shop Shark Joined: Dec 2008 Posts: 319 | Beads of water ABOVE the oil level indicate condensation. Is the oil level normal? How about the coolant level? Water will sink to the bottom of the pan, and gradually make the oil level rise. Major drawback is oil pump picking up water, which isn't near as good a lubricant as the oil  Head gasket is most probable site of a leak, but the fluid levels will tell you if that's the problem. Good luck. cm If you can't fix it with a hammer and screwdriver, you need a bigger hammer.1965 Chevy C10 | | | | | Joined: Apr 2005 Posts: 1,971 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 1,971 | Don't start panicking yet. The milky white is most likely condensation from short trips. It will probably be worse if you park it in a garage with a cold floor every night. Getting it to operating temp isn't enough. You have to keep it at operating temps longer. Like Jerry said, take it out 20 miles, stop and have a burger and coke, then turn around and come back. Check it when you come home. If it makes you feel better, take off the valve cover and clean it off first.
| | | | | Joined: Apr 2009 Posts: 121 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2009 Posts: 121 | i took it for a good 20 minute drive today to get the exhaust done.when i got there, under the valve cover was covered in milky residue, but the oil on the dipstick was fine.when i drove back,it started overheating and pegged out past 220.im going to get an aftermarket temp gauge to make sure im getting the correct reading. anyways, i also got coolant to blow by my 15lb radiator cap.milkyness under the valve cover when i got home was still there.any suggestions? Dan | | | | | Joined: Jan 2008 Posts: 4,963 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,963 | If coolant blew out of a 15# cap, that is a good indication of an overheated condition. My guess is that you have a cooling problem which could also indicate a cracked or warped head. The simplest way I have found to determine if the head needs pulling is by filling the radiator as full as possible, remove all the spark plugs, roll each cylinder to a compression stroke one at a time and apply 150# shop air to the cylinders as they are on their compression stroke. This will show up as bubbles in the radiator if you have a cracked or warped head. If you have to remove the head and it is not cracked, be sure to check it for being straight. Overheating causes heads to warp. | | | | | Joined: Apr 2005 Posts: 1,971 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 1,971 | The milky white in the valve cover isn't going to just go away after a drive. It could stay there for years if daily 20 minute drives aren't the norm. If you took the valve cover off, it is likely you will see it in various placeds on the head too.
Fix the cooling problem first as crenwelge suggests. Remember not to add cold water to a hot cooling system. | | | | | Joined: Apr 2009 Posts: 121 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2009 Posts: 121 | im just curious now as to what would be my cooling problem.ive gotten a bigger diameter water pump pulley to slow down the pump and stop creating bubbles.i have a good sized pusher electric fan. im not sure as to what else could be causing the overheating. | | | | | Joined: Jan 2008 Posts: 4,963 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,963 | Either a stopped up radiator, stuck thermostat will cause overheating. I'm not familiar with 261 water pumps, but impellers can fall off most water pumps. Did you have the radiator cleaned? What is the history of the engine? Do you know that it ever ran without getting hot. If engines sit around a long time, cooling passages can clog up with rust or dirt. Did you buy the vehicle with the engine in it or did you buy an engine and install it? | | | | | Joined: Apr 2009 Posts: 121 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2009 Posts: 121 | it has a new radiator, and we bought the engine which was a real mess when we got it, we mainly just cleaned up the outside and painted it and dropped it in the truck.dont know the history of the engine. | | | | | Joined: Jan 2008 Posts: 4,963 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,963 | I think the first thing is remove the thermostat and drop it into boiling water and see if it opens. A quick test of the water pump is to remove the heater hoses and hold both of them shut with your thumb. Have someone start the engine. If the impeller is intact, you will feel pressure on the one coming from the pump. If that checks out, I would consider getting a leakdown tester. This will not only give you a good indication of the the rings and valves, but if the radiator bubbles, you know that the head needs to come off. I still have fears that the engine got hot before you owned it and the head either warped or cracked. | | | | | Joined: Apr 2009 Posts: 121 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2009 Posts: 121 | are those heads easily warped by having a good overheating.seems like it would be tough to warp that head.ill pull the thermostat tomorrow and boil test it. Dan | | | | | Joined: Jan 2008 Posts: 4,963 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,963 | Yes heads can be warped from overheating. Its quite common. A machine shop can true them if they are not cracked. Cracks can be repaired, but I don't think its worth it. | | |
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