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Author Topic:   oil pressure
Pigpen
Member
posted August 31, 2003 06:02 PM
I have a mostly stock 350 with about 5 races on it.... last night the oil pressure during the race dropped to 20 and was slowly getting lower all the way around the track. normally it runs about 65 or so, the water temp never got above 165. after the race I replaced the oil filter, tried a different gauge, pulled the gauge lines and fittings off to check for resistance and today I pulled the pan to check the pickup... I found nothing wrong with anything and no metal shavings.... what do you guys think is the cause?

[This message has been edited by Pigpen (edited August 31, 2003).]

[This message has been edited by Pigpen (edited September 01, 2003).]

Eljojo
Member
posted August 31, 2003 07:14 PM
Did you check the filter you removed at the track for shavings? I personally suspect you lost a bearing. While the pan is off I would be pulling caps!


Pigpen
Member
posted August 31, 2003 08:09 PM
Yea, I cut the oil filter open.. there was nothing in it. I just pulled the pump apart... the relief spring looks good, the pump gears are not spinning on the shaft. I pulled the first main cap and the bearing looks good... who knows whats wrong....


waltonjr1
Member
posted August 31, 2003 08:25 PM
Check the oil pump shaft,maybe it broke.

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DEANJR#22


hamer36
Member
posted August 31, 2003 09:12 PM
spun a bearing


Pigpen
Member
posted August 31, 2003 10:22 PM
The oil pump shaft is steel and is fine... if it spun a bearing would'nt there be metal shavings?


merlinmech2
Member
posted September 01, 2003 07:19 AM
One of the plugs behind the timing chain? Pressure would be zero at idle though.


dirtracer7
Member
posted September 01, 2003 07:58 AM
Fram filter??????


Pigpen
Member
posted September 01, 2003 08:15 AM
pulled the timing cover, and all three plugs were there. No, it was an ac filter(tried a different one also) any more suggestions? thanks for the help so far....


rico 08
Member
posted September 01, 2003 08:40 AM
Cam bearings have a big effect on oil pressure,that's where i'd look.


nvracer
Member
posted September 01, 2003 01:33 PM
I agree with rico, Cam bearing can spin out or part way out, if not installed correctly, causing what you are seeing.
Just a thought.


Pigpen
Member
posted September 01, 2003 03:39 PM
I thought that would increase oil pressure, since it would be making the hole smaller on the cam bearing...


Pigpen
Member
posted September 01, 2003 04:24 PM
I just found the crankshaft endplay was about an 1/8 of an inch... I know this is a problem but could this be the cause of the oil pressure problem?


autoshop
Member
posted September 01, 2003 04:39 PM
I moved it in an out does not feel like it is sticking...... the pan is a claimer style pan...


FastEddy
Member
posted September 01, 2003 10:17 PM
Everyone would sure think that if a main or rod bearing spun, there would be metal in the filter and the pan. Even still, I would have to pull the caps just to be absolutely sure. If all were ok, then I would pull the cam and check it. If all else fails to produce, you could try another oil pump. I think that is what I would do.


rickb33
Member
posted September 01, 2003 10:18 PM
1/8 of an inch endplay?There's ur problem,probably the rear main or a broken crank.


dirtracer7
Member
posted September 02, 2003 06:13 PM
I don't think I'd be much worried about oil pressure with 1/8 in. end play sounds like the thrust bearing is chewed up.I started a season with .007 end play and seen real fine copper particles in the oil end play was @.017 pulled the pan and replaced thrust bearing and finished the season.I had .022 side clearence on the rods.If you have.125 you have other parts getting or already damaged.Time to open it up.


Pigpen
Member
posted September 03, 2003 08:36 PM
I pulled the rear main, and the thrust part of the bearing was badly worn... I ran 1 weekend with a driveshaft that was a little to long. I just hope the endplay is the problem with the oil pressure, not a seperate problem... I plan on putting a new bearing and oil pump on and trying that, hopefully I will have it done by next weekend...


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