A co-worker told me that he uses a new AC Delco oil filter on his 90 something pickup V-8 TBI that has a check valve in it and this has stopped his lifters from bleeding down between startups. Says that this new filter stops his lifters from ticking on initial startup. Comments?
-
-
Re: C3 Oil Filters
Jim-----
Yes, it's true. The AC PF-1218 replaced the old PF-35. The PF-1218 has the check valve; the PF-35 does not. It was my understanding, once upon a time, that the PF-35 was to be discontinued. However, maybe because it's been around so long and some folks just can't get used to using anything else, GM has, apparently, decided to keep the PF-35 in the inventory.In Appreciation of John Hinckley -
Re: C3 Oil Filters
Joe,
Quite true. I was puzzled as to why the later recommendations were 1218 instead of the 35 but that is the reason. This appears in GMC trucks also.Comment
-
Re: C3 Oil Filters, other numbers
Is there any other AC filters that have this feature? Namely the filter used on the late model, 94-95 LT1's, PF 52, I think.Comment
-
Re: C3 Oil Filters, other numbers
bruce-----
Yes, the PF-52 has the same feature as the PF-1218. The original filter used on 92-93 LT1s was the PF-51. For late 93 or the 94 model year, the filter was changed to the PF-52. At about the same time, the PF-51 was discontinued and the PF-52 specified to SERVICE all 92+ LT1s. The PF-52 is the correct filter for all 92-96 LT1s and 96 LT4s. However, it's not technically "correct" for 92-93 LT1s. But, swap labels and who'll know the difference?
Actually, for at least 92-93 LT1s, the PRODUCTION PF-51 oil filter was a special black-painted filter (instead of blue) and it had a special black and silver label. This filter was only used in PRODUCTION and was not available in SERVICE. This way, if the zone rep found one of these filters on your Corvette with 40,000 miles and a blown engine, they KNEW that you hadn't changed your oil as the warranty requires. In later PRODUCTION, possibly late 93 onward, the PRODUCTION and SERVICE filters were the same blue color and label. Perhaps, this change took place with the change from the PF-51 to the PF-52.In Appreciation of John HinckleyComment
-
Re: C3 Oil Filters, other numbers
Thanks Joe....I thought I had heard this B4, but wasn't sure.Comment
-
Gotta ask-
how does having a check valve in an oil filter stop the lifters from bleeding down?Comment
-
Re: Gotta ask-
Mike - this prevents backflow in the oil galleries and the oil can't drain out of the lifter feed holes...so there is no pump up time when started. It also means you get oil to the valvetrain components much quicker, and since 80% of engine wear is at startup, this helps add longevity to your engine....CraigComment
-
Re: Gotta ask-
O.K. so I gotta ask, does the oil drain down when removing the filter? Do you get more mess when removing the filter. I would think there would be oil above the filter even after punching a hole in the filter and draining it seperatly. Will these same numbers fit the newer big blocks? It does sound like an improvement.
Thanks JohnComment
-
Re: Gotta ask-
John----
Yes, oil does drain down when removing the filter, but I don't think that you'd notice the difference between a check valve and non-check valve filter. When starting an engine after a filter change, there will be a short period of no engine oil pressure. That's why you should never rev the engine immediately after starting. Just turn the key and let the engine start without touching the accelerator, if possible. Also, the momentary period of no oil pressure can be further by filling the oil filter with oil before installation. I always do this.
The PF-1218 will fit all 68-02 Mark IV, Gen V, and Gen VI big blocks. The PF-1218 is not applicable to the new 496 cid big block used in some 01-03 pick-ups and marine applications. That engine uses a new oil filter, the PF-454. I don't know how that filter differs from earlier varieties. Yet, anyway.In Appreciation of John HinckleyComment
-
Still doesn't click-
why wouldn't the oil just flow backwards to the lowest 'open' spot in the lubrication system, ie. the main bearings?
Am I missing something here?Comment
-
Re: Still doesn't click-
I agree. The oil filter is vertical-up. It is filled with oil on shut down and start-up. What does a check valve do in such circumstances?Comment
-
Re: Still doesn't click-
Sounds like marketing hype to me - I can't count the number of cars I've had in the last 40+ years with hydraulic lifters, and not one of them has ever "ticked" at startup and then quieted down when the oil pressure came up (but I remember some early 50's Olds V-8's that did that). Every Ferrari I've owned has used the Fram PH-2804-1 filter (special filter with extra-heavy can and a check valve), as Ferrari mounts the filters upside-down on top of the engine and they need the check valve so they don't drain down after shutdown and don't make a mess when you unscrew them at change time - they also run 90 psi oil pressure hot (and up to 160 psi at cold start), which will blow the can right off a standard filter. The -1 is only $1.50 more than the run-of-the-mill PH-2804, don't know what the price premium is on the GM check-valve filter.Comment
-
Re: C3 Oil Filters, other numbers
Can you tell me the new number for a PF-25 ?Comment
-
Re: Still doesn't click-
only engines that have the filter in a non vertical postion need a check valve. the ZR-1 needs one because even though it is mounted vertical it is up side down and it will empty when you shut off the engine.i found this problem back in the 60 with a caddy that i bought used that had a horizontal mounted filter. it had lifter rattle when started but it had a pennzoil filter and as soon as i change to the correct AC filter the rattle was gone. the "iron duke" 4 cylinder engines had the filter mounted horizontal and GM speced a PF51 which had no check valve but the PF 52 did. GM later speced the PF 52 for the engine did away with the PF 51. this new filter may also be used on a engine that does not have a vertical mounted filter.Comment
Comment