Club Cobra

Club Cobra (http://www.clubcobra.com/forums/)
-   Shop Talk (http://www.clubcobra.com/forums/shop-talk/)
-   -   351W Low oil pressure at engine idle. (http://www.clubcobra.com/forums/shop-talk/10422-351w-low-oil-pressure-engine-idle.html)

Okiesnake 08-19-2001 08:58 PM

351W Low oil pressure at engine idle.
 
351W Low oil pressure at engine idle.
The engine seams to be running OK and feels and sounds strong.
My 351W’s oil pressure at idle drops down to around 10 PSI when warm. The engine has less than 500 miles on it. When cold, the engine runs at about 40 psi at idle and about 60 PSI with engine speed over 2,000 RPM’s. After warming up the pressure is about 25 to 35 PSI except at idle when it drops down to 10 PSI.

For the first 300 miles the idle pressure stayed around 40PSI then recently it dropped down to 20 PSI at idle. I change the oil around 400 miles hoping this would help. I used Mobil 1 10W-30 and used a Ford performance FL1HP filter. I have a remote oil filter and an oil cooler.
Help! I am worried.
Okiesnake

Cobranut 08-19-2001 11:19 PM

Okie,

I wouldn't run that motor any more until you can get it checked out.

I'd be leary of anything under 20-25 psi at hot idle, and you generally want 10 psi per 1000 RPM at speed. IE: 50 psi at 5000 rpm, 60 @ 6000, etc.

The drop after 300 miles indicates something changed in the motor. You could have a bad bearing or it could be the oil pump picked up a shaving missed during block cleaning.
It could also be as simple as a stuck relief valve in the oil pump.

Just have it checked before more severe damage is done.

Good luck,
David

Rick Parker 08-20-2001 01:31 AM

Oil pressure concerns
 
If you have the filter that you recently took off carefully cut it open and look for signs of a bearing material or other foriegn material. One thing to also consider is the oil pump being used for your application. With a remote filter be absolutly sure the oil is flowing through it the right direction and with an oil cooler and related lines it may be necessary to utilize a high pressure or high volumne pump because of the additional amount of oil that is being moved through the system. Check with your engine builder for recomendations in hose size, use as few 90 degree fittings as possible as they restrict flow considerably, and keep the hoses as short as possible. The engine needs more pressure than you indicate. Also eliminate the possibility of a bad gauge.

Good luck
Rick

BJGreen 08-20-2001 02:14 AM

If you are using an electrical guage I suggest you double check with a mechanical unit. I have had several electrical guages that were much less accurate than the mechanical units.
good luck

Okiesnake 08-20-2001 05:56 AM

My engine uses a mechanical pressure sending unit & guage

marmmansa 08-20-2001 12:45 PM

pressure
 
Are you using synthetic oil for break in I thought it is not recomended untill engine is broken in.**)

Okiesnake 08-20-2001 03:51 PM

I originally did not use synthetic oil. I was going to wait until 500 miles (after break in). However, I went ahead and replaced it a little early because it was so close.

marmmansa 08-20-2001 06:05 PM

pressure
 
you should talk to your engine builder on when you should go to synthetic I think they say 1500 2000 miles.**)


All times are GMT -7. The time now is 09:36 AM.

Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2026, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
The representations expressed are the representations and opinions of the clubcobra.com forum members and do not necessarily reflect the opinions and viewpoints of the site owners, moderators, Shelby American, any other replica manufacturer, Ford Motor Company. This website has been planned and developed by clubcobra.com and its forum members and should not be construed as being endorsed by Ford Motor Company, or Shelby American or any other manufacturer unless expressly noted by that entity. "Cobra" and the Cobra logo are registered trademarks for Ford Motor Co., Inc. clubcobra.com forum members agree not to post any copyrighted material unless the copyrighted material is owned by you. Although we do not and cannot review the messages posted and are not responsible for the content of any of these messages, we reserve the right to delete any message for any reason whatsoever. You remain solely responsible for the content of your messages, and you agree to indemnify and hold us harmless with respect to any claim based upon transmission of your message(s). Thank you for visiting clubcobra.com. For full policy documentation refer to the following link: