[Healeys] OIL PRESSURE

[Michael Salter]

There seems to be some misunderstanding of the function of the oil pressure relief valve.
The valve controls maximum oil pressure and maximum oil pressure ONLY.
Until such time as this pressure is reached the oil pressure relief valve remains closed.
Changing or "shimming" the spring will only affect the MAXIMUM oil pressure.
The maximum pressure is limited by the oil pressure relief valve to prevent problems like burst oil filters and hoses, excessive loads on the oil pump and its drive particularly when the oil is cold.
Just sayin'

M





________________________________
From: Healeys <healeys-bounces at autox.team.net> on behalf of Richard Jim Hockert <rjhco459 at gmail.com>
Sent: Wednesday, July 23, 2025 9:39:42 p.m.
To: Seigrist Alan <healey.nut at gmail.com>
Cc: healeys at autox.team.net <healeys at autox.team.net>
Subject: Re: [Healeys] OIL PRESSURE

The change in oil pressure is normal.
1. As others have noted, oil thins as it warms, thus the friction resistance  is reduced;
2. The oil pressure relief valve is additive to the friction pressure.  If you increase the spring pressure in the valve, pressure will increase both at cold start and during warm running conditions;
3. The pressure crated by the oil pressure relief valve can be increased either by replacing the spring or by shimming under the spring. You can experiment with different shim thickness - a flat washer will fit under the spring;
4 as the engine internals wear and tolerances increase, oil pressure falls. In a well used engine multi-grade oil is appropriate 30W50 for example.
5 as long as you are reading 10 pounds per 1000 rpm, you are safe.
6 If you shim too much so that the relief valve becomes inoperative, you can blow the filter off……
Best regards,
Jim

On Jul 21, 2025, at 4:14 PM, Alan Seigrist <healey.nut at gmail.com> wrote:


As long as you are around 20 psi it should be okay, but you may want to consider replacing the oil pressure spring.  It's a pretty easy replacement and you can do it in about 5 minutes.

what oil are you running?  You should be running 20W-50.

Alan

On Mon, Jul 21, 2025 at 2:33 PM carl and gerry rubino via Healeys <healeys at autox.team.net<mailto:healeys at autox.team.net>> wrote:
COLD START 60 LBS. DRIVEE ACROSS TOWN 50, ON HIGHWAY 60, BACK IN TOWN DROPS TO 20 IN 3RD GEAAR, 30 IN SECOND GEAR,

IS THIS S A PROOBLEM?

NO OIL LEAKS ANYWHERE-DIPO STITICK SAYS "ok"

1957 BN-4
_______________________________________________
Support Team.Net http://www.team.net/donate.html
Suggested annual donation  $12.75

Archive: http://www.team.net/pipermail/healeys http://autox.team.net/archive/healeys

Healeys at autox.team.net<mailto:Healeys at autox.team.net>
http://autox.team.net/mailman/listinfo/healeys

Unsubscribe/Manage: http://autox.team.net/mailman/options/healeys/healey.nut@gmail.com

_______________________________________________
Support Team.Net http://www.team.net/donate.html
Suggested annual donation  $12.75

Archive: http://www.team.net/pipermail/healeys http://autox.team.net/archive/healeys

Healeys at autox.team.net
http://autox.team.net/mailman/listinfo/healeys

Unsubscribe/Manage: http://autox.team.net/mailman/options/healeys/rjhco459@gmail.com


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://autox.team.net/pipermail/healeys/attachments/20250724/4bc6a898/attachment.htm>