[AdamIsAdam]

Originally Posted by nytrainer

HWYSTR455 has a great point there Adam. Is your gauge tapped into the oil filter adapter or the back/top of the block. Either way, though, you are seeing a decrease in previous pressures right?
If you're gonna swing the engine I have a crane and a strong, agile 17 year old son you can borrow. Let me know. We'd be glad to help you.

Be careful, I might just take you up on that offer for labor and cherry picker! My problem now is space and time. I only have a one car garage now. Last time I did this I had double the space.

Yes, it's a change from before. That's what has me worried.

The pickup for my AutoMeter gauges is in the back of the engine near the oil filter. I'll check more closely tonight but I think it's at the filter housing.

Question to all: can I drive the car (gently) until I can get it fixed with this type of PSI? I'm talking about a few hundred miles, usually around 20 at a time.

PS: I've got almost no oil leaking from anywhere now that dino oil is back in. Plus, I'm finally getting double digit MPG with my Qjet (twice that of my Holley). Small victories.

[AdamIsAdam]

Is that round brass thing in this picture above my old filter, is that the sending unit for my oil pressure gauge? I have an electric gauge (I think I may have said "mechanical" earlier, but it's electric)

[STEELCITYFIREBIRD]

If it makes the pressure cold,I'm sure the bypass is moving lots of oil. A positive displacement pump will exploded an oil filter in like 1 second @ start up without a bypass. LOL I watched it happen to a bud who insisted on putting an unknown heavier spring in his pump, lets just say that idea was all wet.


On the flip side of that, if the engine is using that much volume of oil inside that it won't reach or get close to the by pass point spinning high, hot, I'd be looking for more volume from pump and of course pan too, if clearances are in order.

Nothing seems out of order from the info provided on the build. The lack of main clearances and and the rod bearing room all exactly the same,interesting, I don't recall seeing a end play #, or side clearance on rods.

Anyway, this does seem to be a clearance issue, as it is temp dependent. Whether it be bearings or lifters to bore or pump. You had mentioned rear main seal had to be replaced right before you got the car, so that cap was off.

If your going inside after talking with Butler, do your self a favor and just pull it out and have ALL clearances checked(yank crank and check with tools not wax!!!). And make sure rods are installed correctly on each journal, not 180 out. You will be more confident turning it 6k..... where you have you red line set on your tach.
Good luck.


Edit..man I type slow!!!
Your headers may be doing a number on that sending unit also.

[HWYSTR455]

That answered my questions, electric, and at filter housing. I don't trust the gauge. I don't believe it's a check ball issue, just to say. And yes, as long as you don't load it too much and go much past 5k RPM, I think you're good until you are sure there's no issues.

I suggest a mechanical gauge at the back of the block by the distributor, you will generally see 10 or so less psi than at the filter housing, and still think you're good. You can put a mechanical gauge at the filter housing as a test, less variables, and see what your reading is.

40 at 3k is good to go, general rule of thumb is 10 psi per 1000 RPM, to give you an idea. And you will see a dip at higher RPM when the check ball unseats. Could be you are cruising right at where the check ball is unseating too.

.

[nytrainer]

Yes Adam that is the sending unit for the Auto Meter Oil gauge. Anything electrical like that might be worth validating even though Auto Meter stuff is high quality. You can buy a relatively inexpensive mechanical Oil pressure gauge and check that against what you're seeing with the electric unit. That sending unit just unscrews and you can plumb into same spot the fitting and tube of a mechanical gauge and retest. Might be worth the effort if what you're experiencing is a faulty sending unit. If the tubing for the OP gauge is nylon be aware that it doesn't touch the headers.

[Bruce Meyer]

Originally Posted by AdamIsAdam

I bought this car just over a year ago from a friend. The prior damage pictured was from 2007 on my prior car.

This engine is a 1970 400 that was completely rebuilt from scratch using 3 years ago using a Butler balanced stroker kit to 469 cid. Block prepped (line-honed, edges filed off, oil passages rifle brushed, etc.)

The #46 heads have extensive work done, including the obvious screw in studs (not sure why he started with #46, I think it's just what he had), porting and filling exhaust crossover with aluminum.

Yes, I like to play with it and wind it out, but I have never over revved. I shift around 5,200. The bottom end should be good to well over 6,000 with Eagle H Beam rods, keith Black pistons, Federal Mogul Race main bearings, Eagle Cast crank 3" mains 4.25 stroke, 2.200 rod journals etc. The top end is com camp XE274, comp cam lifters #852, and comp cam #995 double springs. Valve guides are bronze, it says they were knurled, whatever that menas. Intake and exhaust seals are poly. rocker arms are C.A.T. 1.65. Oh, and Ferrea Valves (2.11, 1.77)

Oil pressure cold at fast idle of around 1,800 is about 63PSI as shown here:


Oh, and thanks for the kind words. I like the car and am pleased with it so far. Aside from this

Eagle cast crank? Check your crank endplay. Could be a bearing issue with the dreaded Eagle thrust surface.

[AdamIsAdam]

Originally Posted by Bruce Meyer

Eagle cast crank? Check your crank endplay. Could be a bearing issue with the dreaded Eagle thrust surface.

Remember, this all started when I changed my oil. Why would I suddenly have issued like this that start when I changed my oil? (I'm not an engine builder by any stretch, so I'm not trying to second guess anyone. Just honestly asking.)

I spoke w/Jim Butler. He said to cut open my oil filter first and see what it's telling me. Metal in there? is is collapsing? etc. I saved the K&N filter that I put on in November and drove about 100 miles. I'll start with that one. But when I changed the oil last week it looked fine - no metallic flakes that I could see.

Oh, and for the record, I never run it to 6k. I have my shift light set at 5,300 and that's where I shift (when I'm really on it). I just liked that redline tab on the 6k mark. Looks cool.

[Tim Corcoran]

I doubt your problem is related to changing your oil. I would not be worried about 15 PSI at warm idle, but 45 PSI at 4,000 RPM sounds low to me.

[Chris-Austria]

I also have a Butler stroker kit and as low as 20psi oil pressure when the engine is really hot at idle (240°) for example after a long high rpm drive... most of the time (normal usage) the idle pressure will be 25-30psi since I switched to VR1 oil (5w50). It gave me about +5psi compared to the 10w40 I used before. I always use Wix filters, I think they give more psi than a K&N filter and they can handle the pressure.. never had a problem with one of them.

But at higher rpm's my engine will make more psi, for example 3000rpm at 220° oil temp is about 75psi (I use the 80psi pump). 45psi at 4000rpm isn't very much, but at least it's more than 10psi for every 1000rpm

I read that the Melling select pumps or the Butler one can give more pressure and more oil flow, about 6 gpm.

[Chris65LeMans]

Originally Posted by HWYSTR455

40 at 3k is good to go, general rule of thumb is 10 psi per 1000 RPM, to give you an idea. And you will see a dip at higher RPM when the check ball unseats. Could be you are cruising right at where the check ball is unseating too.

.

Good info there. I was wondering why my oil pressure sometimes dipped slightly at highway speeds. (3.73 rear end)

[HWYSTR455]

Originally Posted by Tim Corcoran

I doubt your problem is related to changing your oil. I would not be worried about 15 PSI at warm idle, but 45 PSI at 4,000 RPM sounds low to me.

That's where I'm at, doubt it's related, unless somehow a piece of crap got into the sender or something. But I still suspect the sender, or the lead running to the sender, or to the gauge.

On the clone, I have a Classic Industries electric, and it moves around, reads different at different times. I changed the sender, no diff. Hooked a mech up to test and it's 8-12 psi more than the Classic. So be it.

A 60 psi pump is an approximate, it's based on a spring, so it's not like you're going to get an exact 60 at peak. It may only provide 55, or even 50 at peak, then there's clearances to take into account. The 10 per 1k is a 'general' rule, a little less is still fine.

Now if it was a big change, like if it went to 5, and never goes about 15-20 at any RPM, then I would worry.

Cut the filters open and look for debris, if it's clean, run it. Keep cutting filters open when you change your oil, watch it. Break down and buy a filter cutter, they're like $30 bucks, worth it. For a piece of mind, test with a mechanical gauge. That right there will resolve any doubt.

.

[STEELCITYFIREBIRD]

Where did you get the STP filter, BIG LOTS! LOL

Being an electric gauge, check your electrical connections.
From experience, I never use crimp connections on any thing but temporary connections, they do deteriorate. And with a gauge that works off either voltage or resistance, or voltage controlled by varied resistance. Re crimp new terminal ends or solder them.
It did sit a while.

I need a rev limiter, too many 8-9k motors in my past to control myself.

[AdamIsAdam]

Hey, that STP filter cost me THOUSANDS! (meaning, it came with the car when I bought it LOL)

I'll be cutting open the K&N filter when I get home.

But listen folks, remember that I've lived through this with another car 7 years ago. Same exact scenario: changed oil, small debris got caught in the ball valve in oil pump. And the only thing that cured it was a new oil pump.

When the change is tied so specifically to the timing of the oil change, doesn't that greatly reduce if not eliminate the gauge theory? Also, why would an electrical problem change gradually as the car is warmed up? And vary with RPM?

That being said, maybe I'll swap in a mechanical gauge since I can't pull the motor any time soon. I just hate to introduce more variables.

[HWYSTR455]

Originally Posted by AdamIsAdam

...But listen folks, remember that I've lived through this with another car 7 years ago. Same exact scenario: changed oil, small debris got caught in the ball valve in oil pump. And the only thing that cured it was a new oil pump...

Oh, so are you saying you're sensitive to the issue? Heh-heh! If you want to go down that logic road, then maybe it's with the way you change your oil? Explain to me how it would matter that you changed your oil and it started a check ball issue? Oil is draining out, not in, so IMO, that debris would have gone there anyway, or was already in there, really.

And you don't take your filter housing off or anything when you change the filter do you? Another possible entry point for contamination. Or crap in the filter before you screw it on. \

Think about it.

As for a poor electrical connection, yeah, it can cause inaccurate readings, and those readings can still be skewed even if the needle swings. Hot it can be seeing more (or less) resistance, totally feasible.

Do the mechanical gauge, that will tell you for sure. Don't buy a real crappy one either, they're like $40 with the line kit, you may need it to test again, or even on your next engine.

.

[ta man]

When you say engine temps are at 200?Is that oil temp or water temp?

[AdamIsAdam]

Temps are water temp, not oil temp.

Yes, I know the debris getting into the ball valve during oil change is odd, but it did happen last time for sure. And being that I documented it here in 2007, I see that this time it's exactly the same.

Yes, I actually have doubted my oil changing skills. Sad, but true. I very much had this on my mind when I went to change my oil! I didn't remove the housing, just the filter. I keep a few strong earth magnets on the oil pan near the drain plug now and I didn't even remove them before draining the oil for fear of letting something loose. The used oil looked ok.

I then put the new filter on, added oil and started up the car and went for a drive to get it good and warm before parking it for a few weeks.

I'll try the mechanical gauge. Couldn't hurt and it's easier to do than pulling the motor

[Ben M.]

Everything HWYSTR455 has been saying has been my experience as well. I understand you're sensitive to junk in the check ball, but of the last 3 engines that were new that I had that experience "oil pressure issues" all of them were explained by something he has said (most were flaky gauges, verified with an ohm-meter at the sending unit or with a mechanical). Electric gauges are fine, but I've found that the electric sending units tend to be a bit iffy at times and you have to take them as "indications of pressure" rather than truly accurate measurements compared to an AutoMeter mechanical.

Originally Posted by HWYSTR455

Do the mechanical gauge, that will tell you for sure. Don't buy a real crappy one either, they're like $40 with the line kit, you may need it to test again, or even on your next engine.

This is especially important. I have a known good oil pressure gauge I specifically use for this.

Junk in the check ball... I get that it happens but if our engines are SO sensitive to a little debris, how in the world did Pontiac get so many out of warranty back in the day? We're considerably more in tune and anal about our engines and oiling than the factory or average consumer likely ever was...

[AdamIsAdam]

Well, all I can say is I hope you guys are right about the gauge! You've actually got me feeling hopeful about it!

should I buy an inexpensive gauge or should I buy a tool like this guy used:
https://www.youtube.com/watch?v=I8teB16U0LA

[grivera]

Nothing wrong with that tool, but I would also plumb in a permanent quality full sweep gauge so the pressure can be monitored under various engine speeds, temperatures and driving conditions.

[AdamIsAdam]

Heading to S-K speed now for this
http://www.autometer.com/2-5-8-oil-p...h-phantom.html