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Marty Phipps · 10-14-2002, 05:05 PM

Saturday became a very sad day for me.

Driving home from a training class I was teaching for some local area body shops.

I happened to notice that my oil pressure was starting to drop.
First it was down to 25 lbs, then 20, then 15, then 10.
Mind you I'm 30 miles worth of freeway from home.
I finally find a chance to get off the high way.
and start "limping" the car home.
By the time I finally get the poor ol' 428 home, it's only reading 5 lbs. of oil.
No lifter chatter, or knocking.
But I'm afraid of what I might see when I pull the oil pan.

Marty Phipps · 10-14-2002, 05:05 PM

Saturday became a very sad day for me.

Driving home from a training class I was teaching for some local area body shops.

I happened to notice that my oil pressure was starting to drop.
First it was down to 25 lbs, then 20, then 15, then 10.
Mind you I'm 30 miles worth of freeway from home.
I finally find a chance to get off the high way.
and start "limping" the car home.
By the time I finally get the poor ol' 428 home, it's only reading 5 lbs. of oil.
No lifter chatter, or knocking.
But I'm afraid of what I might see when I pull the oil pan.

Marty Phipps · 10-14-2002, 05:13 PM

I forgot to mention,
I can rev the motor up, and it'll read 15-20 lbs of pressure.
But that's all she'll do.
Any suggestions?

TTS · 10-14-2002, 05:18 PM

Cheer up, no noise is good noise. Could be a simple repair, 5lbs of oil pressure isn't as bad as it seems. Good luck!

TTS · 10-14-2002, 05:19 PM

Sounds more like an internal leak, or a stopped up pick-up. [img]/infopop/emoticons/icon_confused.gif[/img]

ponchopete · 10-14-2002, 07:18 PM

Perhaps a cracked or loose pick-up tube, or a bad oil pressure gauge/sending unit?

"My car would be fast if it had an engine, transmission, and rear axle in it."

cpetrice · 10-14-2002, 07:56 PM

yeah,I agree. no noise is good noise. My 350 when I blew it up,the oil pressure was a steady 40lbs,until the rod shot out the side of the oil pan. I would take off the pan,replace the entire oil pump. see what happens. while your down there,check out the rods and such.

Rick Lightfoot · 10-15-2002, 10:31 AM

It takes a minimum of 5 lbs of oil pressure to "float" the bearings on a Pontiac. I would personally tear it down, especially if there is ANY glitter in the oil.

Malky · 10-15-2002, 03:24 PM

I had a oil pump relief valve spring break and cause a big drop in pressure.

Will · 10-15-2002, 06:10 PM

First, pull off the factory sending unit and put on a mechanical test gauge. If the pressure still reads low (not a faulty sending unit or gauge) then remove the oil filter and cut it open.

If the filter doesn't have metal in it, then your bearings are okay. Could be some other problem like stuck relief valve in the oil filter adapter or in the pump itself.

If the filter is full of metal, time to pull the engine.

Don't jump to conclusions, start with the easy stuff first. Pulling the engine because you have a bad sending unit would suck. [img]/infopop/emoticons/icon_redface.gif[/img]

Good luck and let us know what you find. I'm hoping it's nothing serious.

Marty Phipps · 10-16-2002, 04:55 PM

Thanks for the good tip about the oil filter Will.
I just changed the oil about 200 miles before this happened, so it should be a really good indicator.
I'm running a mechanical oil pressure guage, so I'll pick up another one ant try that too.

Marty Phipps · 10-18-2002, 06:58 PM

Well looks like Saturday is the day to find out.
So far I've drained the oil, no signs of metal or other contaminents.
I've started the process of lifting the motor to pull the pan.
Only fatality so far has been the washer pump.
With any luck I'll have the pan off, and find out what the failure is.
Of course, once I had the car in the air.
I found that my rear rope seal is leaking big time.
I sure wish I knew about the B.O.P. seal at the time I was building the motor.
Any way folks, Here's hoping it's only a failed oil pump.

Marty Phipps · 10-19-2002, 06:06 PM

Ok.
Today was the day to pull the pan.(sort of)
Lifted the motor about 3", can't get the pan out.
I think I probably should have used the oil pan that came in the Firebird, instead of the pan that came with the 428.
It appears that the 428 pan is deeper in the front then the bird pan(sure wish I still had it)
Cause I can't get the pan past the main caps, like I could with the old motor.

Any way, I juggle the pan around enough to access the oil pump.
Did I mention that the oil didn't have any indicators of a problem?
I check the pick up screen, no signs of a problem.
Pull the lower plate off the pump, no signs of any foreign material entering.
At this point I notice that I can see the relief ball in the pump.
I'm thinking to my self, dang that doesn't look like it seats by very much.
I pull the bolt holding the spring off, spring is undamaged.
But the ball is staying in the pump.

Hmmmmm.....
Rap the side of the pump a couple of times.
Out drops the ball, and a tiny half moon piece of clear plastic.
approximately 1/16"x 1/16"x 3/16"
Set the ball back into the pump, whatta ya know!
The check ball now sits deeper in the pump housing.

I remember reading in one of these forums, the importance of tearing down and inspecting a new oil pump before installing.
But it really hit home for me on this one.
I guess I'm lucky it isn't any thing serious, other then the wasted time,gaskets,etc to fix this.
I pretty sure it had to be in the Melling oil pump from the get go.
Since the piece is way too large to get past the screen.

goatseeker · 10-20-2002, 04:19 PM

Congrats on the detective work Marty. I bet you breathed a huge sigh of relief. Have you cranked it back up yet to see if it fixed the problem?

I'm really looking forward to getting my new motor in & getting it cranked. Even though I have the utmost respect for P'Dude's engine building experience - your story shows that all it takes is a leeeetle piece of plastic to wreak havoc.
Tim

http://kurtspontiac.homestead.com/TimSimpson66GTO.html

Marty Phipps · 10-20-2002, 04:58 PM

Looks like it's going to be a while before the 428 is back up and running.
The motor just wont lift high enough to allow me to remove the oil pan for cleaning and reinstalling.

I can finangle the pan around to reinstall the pump again.
But I'm not too sure about enough room to install new gaskets.
Got about 3" to play with.
Of course, once the pan is finally reinstalled, I'll have to see if I ruined anything else beside the washer pump.

Will · 10-20-2002, 09:05 PM

Glad to hear it was just a stuck relief ball!

You are now be one of the converts to the church of "disassemble and inspect". Welcome, brother! [img]/infopop/emoticons/icon_wink.gif[/img]

Half-Inch Stud · 10-21-2002, 05:41 AM

Good going.

The 68GTO project engine needs an oil pump...new used, whatever I can get. PRefer a deep pump for a deep pan.

"11.00/123MPH/1.50 60foot/29.5"/4.10:1/10"/472 #48/Flat HYD/DualQuad/Wenzler/3250Lbs
12.00/112MPH/1.61 60foot/26"/3.31:1/10"/472 #48/FlatHYD/Q-Jet/Torker/3650Lbs"

Scott Misus · 10-21-2002, 06:18 AM

I have several used 60 & 80 psi pumps.

Marty Phipps · 10-23-2002, 04:21 PM

Woo..despair,and agony on end.
Deep dark depression, excessive misery.
If it were't for bad luck....
I'd have no luck at all...........
Woo.. despair, and agony on enddd..

Took a day off from work to get the oil pump in and reassemble the car.
Fired it up.
NO OIL PRESSURE!!!!!!!!!!!
And a god awful racket!!!!!!!!! [img]/infopop/emoticons/icon_mad.gif[/img] [img]/infopop/emoticons/icon_mad.gif[/img]
Retracing everything I did during assembly.
I forget to preoil the pump, and I think I dented the oil pan in an attempt to remove it

So no it's time to yank the distributer out, chuck up the pre oiler shaft, and go for it.
Then I'll need to pull the water pump, timing cover, etc. and see if I can pry the dent out before the crank cuts a hole through it

If that don't work, then it's pull the motor [img]/infopop/emoticons/icon_mad.gif[/img]

428GTO70 · 10-23-2002, 11:00 PM

For the pan, maybe you can get one of those dent pullers that weld a stud on to pull the dent out. Or beter yet maybe even a suction cup puller could work? Be easier than tearing everything down maybe. Good Luck(hopefully good this time).

GR-RRR!

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