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Choreboy
09-05-2003, 14:13
I know that this subject has been talked about before but I need some reassurance.

I am running an Amsoil Dual Bypass filter. When I first start my truck after sitting for more than an hour or so the oil pressure does not build quickly. Sometimes the oil pressure light comes on for just a moment. This is most of the time sometimes oil pressure builds quickly after sitting all night.

My question is whether or not this is the guage playing tricks on me or is there a problem? I do not know whether or not I had the oil pressure issue before the Amsoil Dual filter. Do those of you that run the Amsoil Dual system see the same results? Do those of you who run the Oilguard system have problems with oil pressure upon startup after sitting for some time. Even those of you who do not run bypass filters.

No oil preesure at startup bugs me. :mad:
Do I need to check this out or add another guage to ease my mind?

Thank in advance,
Choreboy

Gbenzx01
09-05-2003, 19:56
Well Choreboy,
here's resurance @ abt 50/50.
Ours does the same thing you are describing when first starting in the am & to lessor extent when sitting for short time.
Do not yet have a bypass system installed & yes expect this to be more pronounced with more plumbing togo thru.
GM guages er not best known for expedience nor accuracy & I agree oil press is first thing to see/saw when grabn the key.

Gben

And btw, Knoxville, Truck/Tractor Pull 5th&6th & wish we could be there! smile.gif

jbplock
09-06-2003, 07:21
On my 03 the oil pressure on the OEM gauge has always come up in 1-2 seconds (with or without the OilGuard Bypass) and remained steady. One thing you could do is plumb in a temporary mechanical oil pressure gauge to see if it tracks the OEM gauge. I did this when installing my oilguard just to be sure I had the correct oil pressure. You can pick up an inexpensive gauge at Wal-Mart or Autozone and plumb it to one of the plugs on the oil filter adapter. Doing this would let you be sure the problem is just with the OEM gauge.

Idle_Chatter
09-06-2003, 07:52
I would suspect that you've got an "iffy" factory gauge or sender, Choreboy, but I'd be as worried as you are to check it out. I've been running an Amsoil dual remote for over two-thirds of my 67,000 miles and have never seen pressure lag for more than a couple of seconds, even on a cold start after sitting for a couple of days. It has taken a bit more on filter changes, especially both filters, when it takes an extra second or two to make up the air in the system (even though I prefill both fitlers, there's still a "bubble" and some air in the hoses). Just a thought, have you second-checked your dual remote hose hookup to ensure that you're flowing in the right direction to-from the filters?

a bear
09-06-2003, 08:57
Does the Amsoil have a quality anti drain back valve to keep the oil suspended. I'm not at all familiar with this unit.

Choreboy
09-06-2003, 20:51
Gbenzx01
Thanks for the reassurance. I think that others have said that their trucks do not always build pressure quickly as well.

Jbplock
I may give your idea a try before changing my filters. How did you plumb in to the system. Do the kits come with adapters that will screw in to the extra ports at the oil filter?

Tom
My system is mounted behind the cross member. This may have something to do with my problem. IIRC your system is close to the engine. I will check to make certain that I have plumbed the filters correctly.

abear
The system has a spring loaded valve to keep the oil flowing in to the by-pass filter. When the pressure over comes the spring force the oil will flow through the full flow filter. There is nothing to say that the oil could not drain back through the by-pass filter. My problem could have something to do with the height or rather how low my system is compared to the rest of the engine.

Thanks for all your responses. smile.gif
Choreboy

jbplock
09-07-2003, 03:32
Originally posted by Choreboy:
Jbplock
I may give your idea a try before changing my filters. How did you plumb in to the system. Do the kits come with adapters that will screw in to the extra ports at the oil filter?
Choreboy,

There is 3/8 NPT plug on the bottom of the oil filter adapter that you could use (shown here (http://community.webshots.com/photo/65003591/65005642hlJEYv)). I used this port as the feed for my bypass filter. Before installing the bypass, I checked the available oil pressure at this port using a mechanical pressure gauge connected with a 3/8 to 1/8 NPT adapter. These gauges usually come with a 1/8 NPT to 1/8 compression fitting that connects to 1/8 plastic tube. The plug comes out hard but it will come out. smile.gif