Whenever I start my `Vert after it has been sitting overnight or longer, it takes about 5 seconds for the oil pressure to come off of zero. During this dry time, the engine makes a racket, then immediately quiets down when the needle moves. After that, it runs fine for as long as you want.

Altogether, I have 5 running Valiants, all with slant sixes. I have owned slants literally all of my life. I have never seen this problem before. It seems to me that the oil pump loses its prime and must pump up again every time it is started.

I attempted to cure this by swapping out the oil pump with a fresh unit. It behaves the exact same way with the new pump.

I am pretty sure this is killing my engine. The engine is a 1967 225. Any ideas are appreciated.

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1961, 1962, 1963 and 1965 Valiant 200. The `65 is a `vert.

You could try the premium oil filter with the built in anti-drain back valve. ( I can find the number for you) Does you oil pump have the standpipe on it?

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

Thanks for the quick response, Rick. My oil pump does not have the stand pipe. I can look around my parts and see if I have one if you think it would help.

So you know, I don't use FRAM or other cheapie oil filters. Also, my four other Slants do not exhibit this behavior. It is quite frustrating.

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1961, 1962, 1963 and 1965 Valiant 200. The `65 is a `vert.

Try a Fleetguard № LF-701, Wix № 51806, NAPA Gold № 1806 filter—they have an inbuilt standpipe.

But let's dig a little deeper here. What kind of oil are you running in this car? How many miles are on this engine? And what are overnight ambient temperatures like where you are right now?

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

that is the one. certainly won't hurt anything to try it.

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

Well, that's one of the ones. (all three I listed have the standpipe)

Of the three, my pref would be the Fleetguard; their filters are extremely well made. But it's also likely to be the hardest to find and most expensive.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

It did not seem too hard to find...
https://www.amazon.com/Cummins-Filtrati ... B001ISCRLS

Hope it is the correct one.

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http://www.youtube.com/hyperpack

- Most of the time it is full of Havoline 10W-30.
- The engine has about 11,000 on a rebuild.
- This week the nighttime has been a bit warmer. Mid 60's to mid 70's.

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1961, 1962, 1963 and 1965 Valiant 200. The `65 is a `vert.

The oil pressure readings go like this: Zero for about 5 seconds, then comes up to 50 psi, or just shy of it. After it warms up, the max drops back to 45 psi. Idling at a stop, it drops back to about 20 psi.

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1961, 1962, 1963 and 1965 Valiant 200. The `65 is a `vert.

I hope so too because I just ordered it.

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1961, 1962, 1963 and 1965 Valiant 200. The `65 is a `vert.

That's more than plenty of pressure, but zero for about five seconds is not optimal, especially since a cold start is going to have the carb on the fast-idle cam. Try out the filter with the inbuilt standpipe and see what happens, but I might suspect a sticking oil pressure control valve, even if the pump is new or recently overhauled. Maybe pull/clean/crocus-cloth it as described in these two threads: thread 1, thread 2.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Dan has a good idea to pull apart the oil pressure valve, since that is easy w/o disassembling anything internal to the engine. Filter is a good idea too. I wonder if the oil pickup inside the pan is cracked or has an air leak somewhere. That would require pulling the engine and oilpan...

Lou

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Home of Slant6-powered fun machines since 1988

Something I have wondered about is: are there any adaptors that would relocate the filter into a downward mounting position without hoses. I always find myself wondering if two of the 90 degree small block filter adapters could be used together to point the filter down.

You might try one of these many doodads if you want a relocated oil filter.

But I think you are going to need hoses. Unless you used the Australian Oil Pump and associated parts.
I believe they used a hard line.

Greg

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http://www.youtube.com/hyperpack

Updating... I purchased one of the Fleetguard LF701 filters that you recommended. It was due for an oil change anyway, so I did that this weekend and used the new filter. That solved the problem. No more dry running on startup. The pressure comes up almost instantly and that awful noise is no longer heard.

I have ordered two more of these filters. Since they are Chinese, I presume they are about to either be extinct or about $75 each the next time I see them. They are already not cheap. Even at their current price, two of them comes to $57.

Since we have determined that this is the problem, the next step is to find a standpipe, so I can go back to using off the shelf filters. Do any of you have a standpipe for a slant six oil pump hanging out in your parts pile? It is a small item that my slant would greatly appreciate.

Thank you for your help with this. It was driving me crazy and ruining my engine in the process.

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1961, 1962, 1963 and 1965 Valiant 200. The `65 is a `vert.