Slow to build oil pressure on cold starts
#1
Track Day
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My search-fu is failing me. 1986 928s (early one). It's taking too long to build oil pressure on cold starts - especially on an incline (nose up hill). Like 10+ seconds. What's going on - bypass valve, pressure relief valve??? It's got me pretty concerned.
#4
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Hmmm. 0W- or 5W-anything is thin as water. Consider using a grade of oil recommended for your car and your climate. 15W-50 or 20W-50 would be good choices. Brand is less important than viscosity.
#6
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If it's hot out and you have that thin of a grade of oil in the motor, your gauge won't register much oil pressure. 15w50 - 20w50 is what will get that gauge reading the proper numbers.
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#8
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Common misconception, or maybe common mis-description. 0W-40: At 0ºC (32ºF), it has the viscosity of 0 single-weight. at 100ºC (212ºF) is has the same film strength and may have the same viscosity as straight 40 weight does at 100ºC. The oil does not get thicker as it gets hotter. The polymer chains keep it from thinning but don't cause it to get thicker.
#9
Track Day
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since I couldn't remember what it got for the last oil change it got 15-40 yesterday. Same issue - very slow to build pressure on a cold start. Instant pressure on a warm start.
#10
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did you also change the filter?
what filter did you install?
are the wire connections tight at the sender?
are the pins clean at the 14 pin connector and do you have a hot post cover?
what filter did you install?
are the wire connections tight at the sender?
are the pins clean at the 14 pin connector and do you have a hot post cover?
#11
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Didn't change the filter - no one had one in stock - will have to order, Pins are clean, wires are tight and there's a hot post cover. Not a sender issue - lifters make a little noise until pressure builds.
#12
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This really needs to be confirmed with a manual pressure gauge.
If indeed you aren't building pressure, then you need to replace the oil pump pickup seal to lower block
If indeed you aren't building pressure, then you need to replace the oil pump pickup seal to lower block
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what filter is in the car now?
have you ever taken the oil pan off?
have you ever taken the oil pan off?
#15
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It's not the type of oil.
May I suggest u remove the oil sender and the check valve assembly above it (watch for the springs and note how it all come apart).
Clean out all the gunk and re-test, and agree that a real oil pressure gauge is the only way to know for sure, especially if you heare lifter noise.
May I suggest u remove the oil sender and the check valve assembly above it (watch for the springs and note how it all come apart).
Clean out all the gunk and re-test, and agree that a real oil pressure gauge is the only way to know for sure, especially if you heare lifter noise.
Last edited by davek9; 06-11-2013 at 11:26 AM.