1996 bronco with new 351w motor installed with around 500 miles. Oil pressure falls off to zero after warmed up at idles. There are some leaks at front and back of motor which might be oil galley plugs leaking. Oil is leaking from oil filter which i believe is from front oil leak. Any ideas how to proceed?
Thanks
Rob
96 bronco 351w/






e4od

 

Best advice is pull the motor out again then disassemble to see what is going on inside.

 

New motor installed from where? when?
Any warranty left I hope
You need to install another one
The bearing clearances are excessive (too loose) making the hot oil pressure go low
Is the motor rattling when the pressure goes to zero indicating your gauge is okay?
Been sitting?
It might just need a high volume oil pump and a reseal
I agree, tear down and inspect for starters reseal and go again after checking the clearances and installing a new oil pump
Inspect your pump rotor clearance

 

Possible oil galley plugs front or rear have issues, reason for oil leaks front and back? Oil pressure spikes above 60 when throttle is pressed.
Thanks.

 

I installed motor several years back, bronco has been a long term project so i would say for sure bronco has been sitting. If I had to guess maybe 5 hrs of run time in last 5 years or more.
Thanks.

 

Well, due to the sitting, there is a possibility the relief valve in the oil pump is just sticking
You could try running a quart of trans fluid through it with the next oil change
Then change the oil filter and the oil quicker maybe 1000 miles
If you never drive it, just leave that trans fluid in there for a while and replace the filter once in a while
Those oil galley plugs
If a High Volume pump was used, they (the machine shop) will usually put a plug in both lifter galleys with a hole in it that bleeds off some of the oil pressure
They put those plugs in the front
Doubt they put one in the rear but how bad is the leak?

 

I actually checked and I installed motor in 2012 and up till this year or so been running motor and local test drives, ouch. Bronco has been a huge project over the years and nor dialing in motor. After installing new exhaust system without all the bad exhaust leaks i started to notice noises from pass side head at idle warmed up but went away after pressing gas pedal. Since I installed mech oil pressure gauge and noticed oil pressure going to zero at idle. I have driven bronco around and she runs like a champ. As far as leak oil I though was coming out of sender, installed all new and still leak. Oil is coming off edge of filter, down drivers side oil pan onto ground. Also oil is flowing down oil pan from front to back dripping on ground. I removed rubber inspection port on front of trans and looks like oil is coming out. Mostly just drivers side but after cleaning and running for several min oil is back and pooling up in same areas. There is some oil around drivers side of timing cover and front main seal. What do you think?
Thanks.

 

If one or more oil galley plugs are loose or out how bad will oil leak be? Front galley plugs would drip back into pan correct?

 

 

Correct
The front galley plugs
If the oil pressure relief ones are installed, the excess oil just flows onto the timing chain

 

I had a problem similar to this with my 351M some years ago. Turned out to the oil sender unit.