Oil Pressure

[shyguy]

/emoticons/[email protected] 2x" width="20" height="20" /> I have come across a problem in the past month. Once I have been driving, and the engine is up to temp, every time I step on the brake pedal or take my foot off the gas the oil pressure guage drops like a rock to no pressure. I have asked my local mech about this and he's not sure what's going on. It doesn't do that when I put it in park, just when I hit the brake.

Chris (

 

[Seabronc]

That's a common problem with Bronco's. It could be a number of things but most likely caused by wear in the engine. Putting it in park usually allows the RPM to be higher than when in gear so the pump is moving faster and keeps the pressure up. It could also be as simple as a pressure sensor. You could have a T put in and a real oil presure gague attached to find out what the pressure actually is. Your mechanic should be able to do that for you and even loan you a gague to check it out, I know mine would.

I have the same problem and have short term solved it by going to a higher viscosity oil for the time being. However, the perminant fix is most likely a rebuild, something I'm putting off for a while since the engine runs so nice as is.

Good luck,

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[shyguy]

That's a common problem with Bronco's.

 

[79bigbronco]

I have had that happen alot, it's a 400 thing, I use Lucas oil stabilizer, & 20w50 oil to keep them going , a cheaper way you can try is change the brgs. & oil pump, did that to mine & it's lasted 8 mths., now the head gaskts are gone, 400's are pieces of sh*t, at least 302's are worth throwing some$$$$ at! My 460 is 2 wk's frm going in, yaaaa!

 

[Seabronc]

I hope it doesn't require a rebuild cause I won't be able to afford that for a dogs age....would be cheaper to just put another 302 in there..  This one has about 150,000 kms on it, and still runs pretty good...what's the best viscosity oil to put in temporarily?  I think 10w30 is in there now.....as well as duralube treatment.  could it have anything to do with the PCV too?  Once I install my new K&N cone filter, I will check to see if i am still having the problem.
Chris

the PCV has a brand new breather filter on, as there was no breather filter on it when I bought the rig in feb.  And the stock air filter is brand new cause the old one hadn't been changed (was jet black).  She purrs like a kitten, and is getting better mileage than when she was locked in on the left side.

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Well, I'm using 20W50 like 79bigbronco suggests. It did just fine all last summer and the engine is running just fine, that was 9 months ago. As long as the pressure stays up with 20W50, I'm going to keep running it. So far it shows no sign of getting worse.

Serious about installing real oil pressure gague. The one on the truck is no more than a glorified idiot light.

Good luck,

>-

 

[Justshootme84]

I agree that the stock oil pressure gauge is not very accurate or reliable. I would start by checking the sending unit on the motor, and checking the oil pressure with a mechanical gauge if possible. Common causes to true low oil pressure on a high mileage motor are worn main bearings, failing oil pump or clogged pick-up tube for the oil pump. If you still have low pressure after warm-up even with the mechanical pressure gauge or hear ANY knocking sounds, or use more than 1qt oil per 1000 miles, the most likely cause is worn mains. Even a new oil pump will not cure that, only an overhaul will.

While you're under the hood, check the metal tube for the PCV valve hose to be sure it's not clogged with sludge. If you're getting alot of oil into your air cleaner from excessive "blow-by", you may also have worn piston rings. Keep a daily watch on the oil usage, and change the filter about every 2000 miles. Look for any metal particles in the oil when you drain it.

 

[79bigbronco]

I did sugest new brg's. with the oil pump, I did all of mine without pulling the engine in a couple of hr's.