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Old 06-09-2004, 06:59 AM
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Thanks for your input.

I did remove and check the gauge bung yesterday, but it wasn't clogged. After that I tried the engine again with the different gauge, but with same results.

I have used Fram filters for 10+ years in my Chevy engines with no problems. This is the first time, however, that I have a high pressure oil pump. I will look into this as well.

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  #17 (permalink)  
Old 06-09-2004, 07:31 AM
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filters

I have used the frams for longer then 10 years with no problems also. But they have changed ..... On another forum 3/4 guys all had the same deal happen to then as me and it was all around the same time. I had the same deal with 2 of my customer motors with in 6 months of my problem. I had them all switch to napa or k&n filters and had no more problems.

Once again this may not be your problem but a new filter is alot cheeper then tearing the motor apart if you don't have to... If it's not the problem your only out a few $$$$$$

Keith
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Old 06-09-2004, 07:59 AM
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when my oil pressure gague reads 0, i just change my oil, and it goes back up again lol
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Old 06-09-2004, 08:14 AM
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1980,
when your 19 years old you can get away with that stuff..... but when you get to 25 or so things like that won't work any more!!!!!!! enjoy it while you can L.O.L.

Keith
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  #20 (permalink)  
Old 06-09-2004, 01:35 PM
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Finmike:
I had the exact same symptoms, but I am sure that the causes are different. Regardless, IMO, the end result (unfortunately) is the same. I believe that if you pull the pan, and also check your bearings, you will discover that they are fried. My pressure would drop just as you described. Despite the fact that it never hit zero, it would rise slowly on restart just as you describe. I ended up having my bearings replaced. Luckily, the crank only needed polishing. I base my opinion on the following comments:

Finmike wrote: “When the engine had warmed up, I took it to around 4500 rpm on 2nd gear, and when I changed to 3rd I noticed the oil pressure gauge falling rapidly. I let off the gas pedal, and the oil pressure stopped falling at 20 psi and stayed there. I idled back to the garage (1/2 mile), the gauge at 20 psi all the time and shut the engine off.”… “I started the engine again, and now the pressure rose slowly to 40 psi at idle and stayed there. I tried 2500 rpm and the gauge stayed at 40 psi and then fell slightly. The engine idled and ran fine, with no extra mechanical sounds, but the pressure was down.”… “The oil had a strange, bronze-ish color but otherwise it seemed fine.”

BOBCRMAN@aol.com wrote: “Better pull the pan.. That bronzish color is usually fine aluminum particles from a bearing failure. The sudden oil pressure drop is definatly not good.”

I would check out your pick-up to pan clearance. I once had an engine with too much clearance because I used a one piece Fel-Pro gasket. It is much thicker and does not crush. I’ll bet you have too much clearance and by the time you hit third gear, the G-force is sloshing the oil (what’s left in the pan) to the back, exposing the pick-up; which then sucks air into the system, causing the pressure drop, and subsequent damage. I hope I am wrong concerning the probable damage to your bearings and possibly the crank. Good luck solving this problem, Ed.

www.edgesz28.com
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Old 06-10-2004, 11:29 PM
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UPDATE

Last night we pulled the engine and took off the pan. The oil pump pickup was not loose, and we measured the pickup height. The bottom of the pickup was 1/4" from the pan, meaning that the screen on the pickup is maybe 1/2" from the pan. Is this OK, too much or too little?

We removed the oil pump and checked the pressure relief valve. It seemed to be seated, and moved in it's bore when pressed with a screwdriver.

We removed rod caps, starting from the front. There was some sign of wear on the #1 and #2 bearing, but nothing dramatic. Smaller signs of wear were on the rest of the bearings. Two friends who are professional mechanics were helping me, and they both agreed that the wear wasn't big enough to lose oil pressure, at least in any significant way.

We took off the cyl heads, rods, pistons and cam and removed the crank next. The main bearings were fine, but there was some wear on the rear main bearing thrust face, the one that points to the rear of the engine. That would explain the bronze-ish color in the oil but again, this would not explain the sudden pressure loss. Or would it?

I'm still puzzled. If the oil pressure loss was due to the HVHP oil pump pumping the pan dry or the pickup being too far from the pan, the pressure should have come up after shutting the engine off and letting it sit for a while. There was not enough damage to the bearings to explain why the pressure did not come up again.

If the pickup was too low or the rod clearances too big, the oil pressure should have been low from the first start, no?

The oil pump pressure relief valve was not stuck open, at least as far as we could tell.

I have new bearings on the way, but I would like to find out why I lost oil pressure before trying again. Any input and/or new ideas would be appreciated.
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Old 06-11-2004, 06:06 AM
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Check your crank thrust flanges. I have seen some poorly finished ones on aftermkt cranks. There should be no wear on the thrust with this low hour engine operation. Was the thrust set properly? You may try using a file and modifying the rear bearing to get more oil to the thrust surfaces.
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  #23 (permalink)  
Old 06-11-2004, 06:41 AM
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I am curious to see what you are calling where. It is perfectly normal for the white(not sure what it is) substance to wipe of the bearings and it could be mistaken for wear. Apparently some people like to scuff off the white stuff so that the bearing surface is exposed. If there are actually wear marks like scratches, I would be concerned on an engine with that few miles.

Chris
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Old 06-11-2004, 07:51 AM
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I'd like to also stress what K-star mentioned. I also had issues with Fram filters lately (within the last year) it sounds too simple but your symptoms sound painfully familiar. Try a Wix or a Napa or a Mobil 1. I literally tore an entire motor down short of pulling the pistons only to have the same problem show up again after restarting. The problem went away when I put a Wix on.
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Old 06-11-2004, 07:56 AM
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TurboS10: By "wear" I meant there was more signs than just the white substance gone. This was evident on #1 and #2 rod bearings. But even these two bearings were not too bad. Scratches etc. were not to be seen, and the crank was fine.

BOBCRMAN: Thanks for the tip. I will check the thrust flanges. The thrust was set properly, but I didn't measure the endplay. There was endplay, i.e the crank was not obviously too tight by looking at it. My bad...I meant to measure it but you know how things go...too much in a hurry to get the engine ready.

Engineczar: I think I will try a Wix too...just for safety
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  #26 (permalink)  
Old 06-11-2004, 08:09 AM
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The explaination on the Fram filters I got was either a defective internal bypass that stays open or the filter media broke down.

Aren't we glad they're ISO 9002 certified?
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  #27 (permalink)  
Old 06-11-2004, 08:17 AM
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Quote:
Originally posted by engineczar
The explaination on the Fram filters I got was either a defective internal bypass that stays open or the filter media broke down.

Aren't we glad they're ISO 9002 certified?
I work for an ISO company. About all ISO is good for is to prove that you document everything the company does in the order of processes and procedures. The company can still put out crappy products.

Chris
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Old 06-11-2004, 09:44 AM
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After reading the posts in this thread, I see my previous answer isn't related to the problem here.

My guess would be the Fram filter. I've seen multiple cases of unexplainable oil pressure loss traced back to this make of filter.

tom
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  #29 (permalink)  
Old 06-11-2004, 10:43 AM
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Quote:
Originally posted by TurboS10
I work for an ISO company. About all ISO is good for is to prove that you document everything the company does in the order of processes and procedures. The company can still put out crappy products.

Chris

"Do what you say, say what you do" for ISO it's ok to make junk.........so long as you say it's junk

http://www.classracer.com/cgi-bin/ne...pg=1&sc=20&x=0

I'm not sure how well this link will work. It's on a drag race forum and the guy talks about Fram filter problems.
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Last edited by engineczar; 06-11-2004 at 10:43 AM.
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  #30 (permalink)  
Old 06-12-2004, 04:11 AM
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Our family business has been a Fram dealer for close to 30 years, and generally our experience with Fram quality has been good. (Otherwise we would have changed our filter supplier ages ago.) But that doesn't mean my problems would not be related to the Fram filter in this instance. Like the person in engineczar's link, I also have the filter bypass plugged. And my symptoms were exactly what he described. This is the first engine for me that has a HVHP oil pump together with a plugged bypass, so I have no previous experience with Fram filters in this kind of setup.

I will use another brand of oil filter when I get the engine back together, just to be on the safe side.

I checked the crankshaft thrust flange yesterday, and I found scratch marks, sort of like someone had run a file there. I did not check the thrust flange when I installed the crank, I trusted the fact that it was a new unit. My mistake, it seems. I will take the crank to our local machine shop to have the thrust flange polished on Monday.
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