Idle oil pressure concerns

[Ross1.8t]

I have a 99 1.8t passat that I installed a amsoil bypass filter on. The filter has been on for almost a year. I also have a dakota digital oil pressure gauge.

My hot (oil temp 200F) idle oil pressure is 12-13 psi. The specification for this engine is a minimum of 14 psi at idle. However at 2000 rpm the oil pressure is at 34 psi and the spec is 29 psi. What is my problem?

The engine has no sludge, as I recently dropped the oil pan to quell my fears of sludge on this sludge prone motor. I really like the benifits of the bypass filter but if it is doing more hard than good I will remove it.

One solution I thought of was some sort of a pressure activated valve that opened on the line going to the bypass when a certain pressure was reached. Does such a aparatus exist, and is it practical? I think this would solve my problem as the oil pressure is only low at idle.

Let me know what you think, Thanks.

 

[Ken2]

I think you have no problem. If you don't like what you have, find the orifice that limits oil flow to the bypass filter. Measure it with the shank of a drill. Fill the orifice with silver solder or braze metal and drill it out one or two drill sizes smaller.


Ken

 

[Gary Allan]

Can we assume that this is a single bypass unit? The restrictor should be very small ..even difficult to see if you're in bifocal range.

One possible cause/remedy (for a problem that I don't think you have). Don't use the spec'd VW filter. Use a common FL1A (buy a cheap one of any manufacturer) and see if you get a better reading. If you're using a typical VW filter, it's got a 30 psid bypass valve. Many here have reasoned that this is due to the media being having finer capture ability ..and higher loading capacity (as well as being reinforced/stronger). With the bypass filter you are providing an alternative path pre-filter/pressure sender ..so the limited flow through the restrictor would be higher then with a conventional filter.

For the first objection to trying a cheap FL1A ..the response is that since you have a bypass filter ..the more robust VW spec filter is not necessary.

I may not have said this in an easily understandable manner ..

 

[sgtgeek]

I agree with Gary Allen....I run dual remote filters ( Perma Cool)on the GTO...FL1A size/type filters.....

 

[Ross1.8t]

Yes, it is the single bypass unit with the smallest size filter. I am using the factory spec oversized filter.

Thanks for the response, but pardon my ignorance what does FL1A mean? Is this just a cheap filter like a supertech at walmart? Is there any oversized FL1A filters avaliable? I would like to keep as much oil in my engine as possible, which is one of the reasons I purchased a bypass filter.

 

[mjo]

There could be a noticeable pressure drop across the oil hose - depending on how long the hose is.

An oversized oil filter is a good idea. Another good idea is to get a spin-on with a silicon ADBV; this will keep more oil in your engine when your engine is shut off by having a better seal.

 

[LateArrivalforLSU]

quote:

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Originally posted by mjo:
There could be a noticeable pressure drop across the oil hose - depending on how long the hose is.

An oversized oil filter is a good idea. Another good idea is to get a spin-on with a silicon ADBV; this will keep more oil in your engine when your engine is shut off by having a better seal.

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I believe Amsoil puts a 1/16" restrictor orifice in their bypass filters, correct me if I'm wrong. With the restrictor orifice there really shouldn't be a pressure drop of any substantial amount.

I definitely agree with the oil filter and ADBV valve.

 

[Gary Allan]

Mine was approx a 1/32 ..but different things happen when you allow oil to bypass the engine in terms of pressure readings. Oil flows incredibly well, when warm, through very small openings. I discovered this when I doubted Ralph and drilled two very small holes (about 1/12 the area of the normal openings in an oil filter) when I used a Permacool sandwich to plumb my MEGAfilter. After warm up ..I had a cold can. No flow.

Anyway, I think that there's a slight impact on his pressure after warm up through the bypass ..but it's of no real consequence.