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Old 09-01-2002, 01:37 AM   #1
WORNBRAKES
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I am back and with problems

Well it has been a month since I last posted. The 3000 mile trip across the country is over and we are settled here in Pensacola, FL. But that did not come without engine problems. I know I burned up my valve guides. There is a little smoke coming out my breather on the valve covers. I think that either my oil pump is going bad or I have worn rod bearings. Oil pressure is fine while I am driveng but when I slow down at a stop light, oil pressure drops. I know some of you have had this problem before, what was you cause? Any pointers would be great.
Thanks,
Mario
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Old 09-01-2002, 09:42 AM   #2
nu2-72
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Good to see you back. Oil pressure depends on the drop. Most Chevys are designed to build pressure of 10 lbs per 1000 rpm's. Meaning if your idle is 30 on a fresh engine at 800 rpm's, it would be around 50 at 2800 or highway speed. If it drops below 10 lbs at idle, I would look at some work very soon. Some drop is normal.
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Old 09-01-2002, 10:35 AM   #3
da-burb
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smoke out the breathers is usually blow-by. Your rings no longer seal the combustion chamber. Pull your breather cap and your PCV valve, run the engine up in rpms and watch the valve cover openings. If it is blowing smoke like a chimney, it's rings.
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Old 09-01-2002, 10:52 AM   #4
6869704X4
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How you liking Fla so far? That make three members that I know of in this area.
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Old 09-01-2002, 10:57 AM   #5
greasemonkey
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Where do you live 6869704x4? By the why Wornbrakes, that's the problem I have with mine too, blowby. At least that's what it sounds like yours has, mine blows clouds all over when I pull the PCV valve.
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Old 09-01-2002, 11:43 AM   #6
6869704X4
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Make that four members. Im in Navarre.
WORNBRAKES, I meant to ask you how much your pressure drops at idle. 10psi per 1000 rpm is minimum. Also, what wieght oil are you running? Here is a good source of info.
http://www.melling.com/techbul1.html
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Old 09-01-2002, 12:07 PM   #7
tom hand
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I love this 10 psi per 1000 rpm rule except for one thing, a stock chevy oil pump won't do it. On a stock chevy oil pump the pressure relief spring is set at 40 psi, it won't go any higher. Most chevys I have seen that the oil pump has not been modified run 10-20 psi at idle and 40 psi cruzing. The tempature the engine is running at will play a major part in what the pressure is at idle, the hotter the motor the lower the idle pressure will be. Also don't trust the stock gauge, if you want to know what your oil pressure is, hook up a quality gauge.
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Old 09-01-2002, 09:47 PM   #8
WORNBRAKES
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I am still using the fossile guage that came with the truck. Before the trip, I would always run at 3/4. Sometimes it would drop a little but not much. Now while I am driving, I am at 3/4 but when I slow for a stop light it slowely dropes to 1/4. On the way here it did it a few times but I was leaking oil so I can see a problem with pressure then. I have fixed the oil leak since and still have this problem. As far as the area members, I believe cyco path is in Robertsdale, AL. Not to far from here. We should all get together some time. Anyone going to the Super Chevy Show in Montgomery this month? The wife and I are planning on it.
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69 C10 305/350
71 K5 Basket case
75 K10 Rescue **Parting out**
77 MG Midget **Parting out**
15 6.7L Cummins
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Old 09-01-2002, 10:33 PM   #9
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My stock pump pushes 55-60 all day long on a quality gauge and has for 141,000 miles. Quaker State 10-40
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Old 09-02-2002, 12:27 AM   #10
O'l Buck
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try some 50wt synthetic
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Old 09-02-2002, 07:05 AM   #11
ChevLoRay
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A heavier viscosity oil will help you get by until you can rebuild your engine....or just replace it with a crate motor. I had a '67 Impala convertible that did all yours is doing, plus when it got about a quart low, and I was in a curve on an off-ramp, the oil light would flicker. So, you know it was running on borrowed time. When I sold it, three years later, it was still doing the same thing.

Since your weather is milder than some other areas, you should be able to run a 20w40 or 20w50 oil, non-synthetic, and have your engine survive for quite some time. As long as you keep oil in it, it will run. Barring any component failure, i.e., spun bearings or oil pump failure, you'll have time to build an engine that will be just what you want.
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Old 09-02-2002, 08:18 PM   #12
WORNBRAKES
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Right now I am running streight 30w in there. Maby I will try some 20w40 or 20w50. I am planning on rebuilding the motor sometime this winter when it is cooler here. Right now the garage is too humid to work in there for longer than 30 min. Thanks for the feedback. I guess I will have to keep a closer tab on the motor than I have had to in the past.
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Hughesville, MD 20637

69 C10 305/350
71 K5 Basket case
75 K10 Rescue **Parting out**
77 MG Midget **Parting out**
15 6.7L Cummins
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