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Oil pressure question again?

Gel

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Hi,
I notice that when I start up my oil pressure goes up to 60psi. I thought it should be lower than this. Maybe this is a good thing. Forgive me but I'm new to all this.
 
Hey, Gel -

Count yer blessings! 60 psi is great at startup. What does it "settle down" to?

Mickey
 
So, its 60-65 at idle when warm & also at speed when warm?
 
10 to 25 at idle and 50-80 at 3000 RPM is the range per Haynes. Pretty much the same in the Moss catalog spec section. Idle should be around 800 - 1000, I believe.

Guinn
 
Pressure at idle is a bit low...you might want to start saving a few bucks for an engine refresh....rings, bearings (actually, you might think about pulling the oil pan & looking at a rod bearing)
 
My pressure never drops below 50lbs at idle warm and holds 60 to 65lbs when running at speed. Of course my engine only has about 500 miles on it since total rebuild. /ubbthreads/images/graemlins/thumbsup.gif /ubbthreads/images/graemlins/thumbsup.gif PJ
 
My 78Bs got well over a 120K on it and the engine has never been apart. But even with that amount of mileage she still holds her oil pressure pretty well after it’s warmed up.

On start while it’s still cold I’ll get about 50 to 55PSI at idle. As she warms up the psi at idle slowly starts dropping off, but it never gets below 25psi once she’s completely warmed up. At speed or under load I see bout 65 to 70psi (warm or cold).

I suspect that even after my engine swap (I’m building another engine right now), my old engine would be a great candidate for a rebuild down the road.
 
If you're used to "other" engines' oil pressure readings the MG's will scare ya. Cold idle can be really high. Bret's is about an average reading.
 
[ QUOTE ]
Pressure at idle is a bit low...you might want to start saving a few bucks for an engine refresh....rings, bearings (actually, you might think about pulling the oil pan & looking at a rod bearing)

[/ QUOTE ]

I think Guinn was saying that 10-25 psi at idle is what Haynes says is acceptable, not what he has....
 
Mine's about identical to Bret's oil pressure readings.
 
[ QUOTE ]
that 10-25 psi at idle is what Haynes says is acceptable

[/ QUOTE ]

One of the reasons I don't trust Haynes manuals!

I'd almost bet that any MG with that low oil pressure at idle has some brass showing on the bearings.
 
Mine (well, Janet's, really!) has whatever the mark between 50 and 100 is on startup. And even when warm, it doesn't drop far below that at idle. But then, it's a fresh rebuild. And I checked it with two different gauges - both had the same readings. It'll be interesting to see how long it stays like this.

Mickey
 
Mickey - IMHO any MG that has less than 25psi at idle needs an engine refresh! (& I think 25psi is too low as I've seen engines like that with worn bearings!)
 
I gave you wrong info. My MGB runs 60psi at idle and also at highway speed, cold or warm. My old Jeep has low pressure.

Guinn
 
Well, if nothing else, this thread made me check my oil pressure. It's always been good on the Midget, but yesterday, I just had to verify everything. 75 psi cold startup, 45 psi at hot 750 rpm idle, and 65-70 psi hot at speed. This is an untouched, 65,000 mile engine, running the old standby, Castrol 20W50.
I can live with that.
Jeff
 
[ QUOTE ]
Mickey - IMHO any MG that has less than 25psi at idle needs an engine refresh! (& I think 25psi is too low as I've seen engines like that with worn bearings!)

[/ QUOTE ]


Tony, easy for you to say! I love that expression, engine refresh . You make it sound so simple.
We on the other side of the wall, Triumph that is, call this a major overhaul! Perhaps the MG is easier work on. I doubt it.

It's really like pulling teeth. Oh, wait, that is easy. I do that for a living. Maybe it's like....whatever.



Bill
 
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