Register or Log In To remove these advertisements. |
|
|
|
Thread Tools | Display Modes |
06-19-2018, 01:02 AM | #1 |
Revitalizing a 6T C10
Join Date: Aug 2017
Location: Santa Barbara, CA
Posts: 209
|
Small Block Normalcy (what should it be doing?)
Lets start with the basics ..
= makes noise, smells bad, gets hot, leaks oil= makes noises - check! sounds great smells bad - check! smells like old truck should gets hot - check! yep- stays cool since the shroud was installed leaks oil - check! shes absolutely a leaker - we will deal with that in a bit I have a small block in my recently resurrected truck thats starting to give me some worries (oil pressure) So, this is an unknown year / make / model of small block - its got a smog era intake on it, and a rebuild / re manufactured tag on it. I am trying to get an answer as to what normal oil pressure for a well worn small block is ( i have been told lots of different answers ) So I have been checking the oil level before I start it, and here is what I am seeing Ive got a 80 psi gauge - probably a bit of a wide swing, but thats what ive got for now... im checking to see if I can borrow something that may show some better numbers Cold Start : 40 PSI @ Idle Freeway : 30 PSI @ 55 mph / 2900 rpm Off Freeway (after freeway driving) : 20 PSI @ 30 mph / 1900 rpm Hot idle : 5ish? Is this acceptable? If not, what are the odds that I can just pop an oil pump in there? It looks like the pan can come out with having to pull the engine - I am working on the street, so I want to try and plan what I can do and get it done in one go. Thank you! |
06-19-2018, 07:59 AM | #2 |
Account Suspended
Join Date: Jun 2015
Location: No longer here
Posts: 1,000
|
Re: Small Block Normalcy (what should it be doing?)
10 lbs of pressure for every thousand RPM is the rule of thumb, If you pull the the oil pump it may not just be the pump.....once you pull the pan, oil pump, pull off the bottom half of the rod bearings and CHECK the bearings, you may find the bearings have a bit of clearance....just my 2 cents. Have fun on the street and good luck !!
|
06-19-2018, 09:38 AM | #3 |
Registered User
Join Date: Aug 2009
Location: Bowser
Posts: 13,531
|
Re: Small Block Normalcy (what should it be doing?)
First thing you do is put a good mechanical gauge on it.
If you get the same numbers and you hear no rattling at idle, keep driving it. |
06-19-2018, 06:45 PM | #4 |
Senior Member
Join Date: Dec 2011
Location: Moraga, CA
Posts: 809
|
Re: Small Block Normalcy (what should it be doing?)
What viscosity oil are you using? I have used heavier oil (DELO 15W-40 or even tried different brands of 20W-50) to slow down leaks in my older vehicles. You're in So-Cal, so you can probably get away with using heavier if you need it.
If you were in the northern US or Canada, I'd say only do that in the summer. Next oil change put in the heavier stuff. See if it makes a difference with the oil pressure and leaks and noise.
__________________
(Very) Slow-Going Build Thread: Stock 1970 Short Step with Stock 1970 LT-1 http://67-72chevytrucks.com/vboard/s...d.php?t=567340 |
06-20-2018, 09:10 AM | #5 |
Registered User
Join Date: Aug 2012
Location: Oklahoma City, OK
Posts: 2,509
|
Re: Small Block Normalcy (what should it be doing?)
Normal oil for a stock 350 is 10w-30. The only number that is a little bit worrisome is the 5psi at hot idle. But you are probably in a part of the gauge scale that makes that a bit of a guess. If you don't have lifter rattle/clatter at hot idle, don't worry too much.
Changing to a thicker oil to 'fix' low oil pressure just masks a problem, it doesn't fix it. Valve cover gaskets are the leading suspects for SBC oil leaks. As for bad smells, a small fuel leak can create a lot of bad engine smell. |
06-20-2018, 11:11 AM | #6 | ||
"I ain't nobody, dork."
Join Date: Sep 2007
Location: Whidbey Island, Washington
Posts: 8,921
|
Re: Small Block Normalcy (what should it be doing?)
If straight 30wt wasn't so hard to find... I'd still be running that. LOL.
Main rule of thumb I've always gone by... If a SBC ain't leaking oil... it's out! Gary
__________________
'cuz chicks dig scars... My 1972 GMC 1500 Super Custom (Creeping Death) "long term" build thread. The Rebuild of Creeping Death after the wreck Quote:
Quote:
|
||
06-20-2018, 10:41 PM | #7 | |||||
Revitalizing a 6T C10
Join Date: Aug 2017
Location: Santa Barbara, CA
Posts: 209
|
Re: Small Block Normalcy (what should it be doing?)
Quote:
Quote:
Quote:
I am thinking about doing an oil-change, and sticking a camera up the drainplug to see if I can see anything worrysome Quote:
It doesnt' sound any different engine wise hot vs cold, so I guess thats a good thing ? I have no problem putting different oil in, but as you said, if I am just manipulating the gauge, won't we still have the same problem of not building enough pressure? Ive got a set of rubber gaskets to go on Quote:
Thanks All - I will report back shortly... |
|||||
06-21-2018, 04:11 PM | #8 |
Senior Member
Join Date: Dec 2011
Location: Moraga, CA
Posts: 809
|
Re: Small Block Normalcy (what should it be doing?)
Yes, that and it helps with the diagnostics. Or maybe buy a little time before getting the rebuild it really needs. It's bought me at least 4-5 extra years with my daily driver Accord.
__________________
(Very) Slow-Going Build Thread: Stock 1970 Short Step with Stock 1970 LT-1 http://67-72chevytrucks.com/vboard/s...d.php?t=567340 |
06-22-2018, 06:26 AM | #9 |
Registered User
Join Date: Oct 2013
Location: Maine
Posts: 2,351
|
Re: Small Block Normalcy (what should it be doing?)
I'd say it is better to mask the problem than tear into an engine that still runs ok. They like 10w30 when they are new and tight. When they get older they start liking some 15w40. When the bearings get loose that nice 10w30 has a hard time filling the extra clearance.
__________________
76 Chevy K20 76 GMC K15 77 Chevy C10 77 Chevy K10 |
06-28-2018, 10:51 PM | #10 | ||
Revitalizing a 6T C10
Join Date: Aug 2017
Location: Santa Barbara, CA
Posts: 209
|
Re: Small Block Normalcy (what should it be doing?)
Quote:
Quote:
I did an oil change last night, dang I love that truck, no floor jack, just a drainpain and a wrench - 15 minutes in and out. Put in 5.5 quarts of Del0 15w40 - oil pressure was definitely better last night (both cold and warm), but this morning after the drive in to work, it still feels like its sitting a bit low on the gauge (buddy is looking for correct adapters for his gauge) I will try and attach some photos to help illustrate what Im seeing. this first picture is warm idle the night of the oil change Warm idle night of oil change by Keith, on Flickr this second picture is warm idle the morning after the oil change Warm Idle day after oil change by Keith, on Flickr I am wondering if there may be something in the pan that is getting stuck towards / infront of the pickup, but if I am dropping the pan, I will probably change the pump anyways. Thanks all! |
||
06-29-2018, 08:06 AM | #11 |
Registered User
Join Date: Mar 2013
Location: Campbellsville, KY
Posts: 888
|
Re: Small Block Normalcy (what should it be doing?)
That pressure is low, but the engine is still lubricated so as long as it's not something going downhill fast it could last a good while. I don't default to thick oils, but I second the suggestions to put some 15w40 in it and see what it does for it. Especially in the warmer climate it certainly won't hurt it, and if it brings your oil pressure up a bit I'd run it and not worry. BTW, in your stock engine high ZDDP content isn't necessary so any 15w40 is fine - Rotella T4 is cheap and has a good reputation.
__________________
Alex V. ------ 1967 C10 Suburban, 350/NP435, Green/Green, PS, PB, HD cooling, charging, shocks, and springs. 1985 GMC C3500 SRW, Sierra Classic, 454/TH400, white/blue. |
Bookmarks |
|
|