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bjbarbieri

Update on my oil blow out...

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As some of you guys know, a few weeks ago, I got to take my '67 2000 tilux for it's first drive around the parking lot at the shop I work at after it had sat for 15 years. A week later, I took it around the lot again, but this time, I lost 3 quarts of oil through the oil filter o-ring, leading me to believe that I had a faulty oil filter, or more likely, a seized pressure relief valve on the oil pump. I plan on pulling the pan, AGAIN, ugh, to disassemble the oil pump pressure relief valve, and make sure it is able to move freely and smoothly, but before I did that, I wanted to do a compression check and oil pressure check to see if I was going to end up doing an engine "re-seal" or rebuild over the winter. I had some old compression test numbers that I had found inside the car, and I wanted to see what kind of variance I had since the last time it was checked.

IMG_20121112_090347.jpg

on the 5th of March, 1987, one of the previous owners took the the car to have a compression test done. Cylinder 1 was @ 120 psi, Cylinder 2 was @ 115 psi, Cylinder 3 was @ 105 psi, and Cylinder 4 was @ 110 psi. The mileage on the car at this time was somewhere in the neighborhood of 57,000 miles.

I had found a couple of other older compression tests written in the shop manual that was in the trunk. One was dated 3/31/73 @ 49,234 miles and showed [email protected], [email protected], [email protected], and [email protected] The other test was dated 9/17/73 @ 56,953 miles and stated “shortly after over-heating”, showing [email protected], [email protected], [email protected], and [email protected] Not sure how that last cylinder could go up that much. Maybe it was operator error.

The compression test results from yesterday are as follows:

Cyl 1 @ 115, 2 @ 120, 3 @ 105, and 4 @ 95 PSI.... Not too different from 1987.

What do you guys think about those numbers? Acceptable for a gasket "re-seal" and getting by for a couple years, probably until the body work is totally done?

After I did a compression check, I hooked up an oil pressure tester gauge. I found that at idle, the pressure varied from 25 to 40 psi (my carbs need some work, and the idle is loping up and down a bit) but once I gave the car some throttle, the oil pressure would spike up to 100 psi and higher. Is that excessively high? It seems so to me, and would probably confirm that the oil pressure relief valve is stuck closed, resulting in my oil filter blowout....

I'll post a couple of videos showing what I found.

Here's the car just at idle:

Here's the oil pressure gauge reacting to throttle:

and here's a video of the tach and oil pressure gauge reacting together.

at about 4000 RPM, the gauge is spiking at 100+ psi,

Do you guys think that's excessive? I'm going to pull the pan and check the oil pump anyway, but just curious what your thoughts are.

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I'm amazed that your car came with comprehensive records!

Have you taken apart the Solex carbs yet? I wonder what venturis/jets are in them.

Jim

Jim,

I haven't gotten into the carbs yet...I've been hesitant because the car actually runs, ha ha...but I DO have another set as back ups.... I'm sure I will here shortly...

Nobody ever chimed in...does 100+ PSI on the oil gauge under revving between 3500-4500 RPM seem excessive?

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BJ,

Here is what my NK factory manual (in Spanish) states on oil pressure. The top row is for oil pressure at idle (top range) and at maximum RPMs (bottom range). The bottom row is the over-pressure valve open point. All values in atmospheres. Hope that helps!

ScreenHunter_02%2520Nov.%252018%252007.57.jpg

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Blue book spec chart for oil pressure:

Oil filter pressure relief valve opening pressure: 2.2 bar (31.3 PSI)

Oil pressure light illuminated below: 0.2-0.5 bar (2.8-7.1 PSI)

Oil pump pressures:

Idling speed: 1.8-1.2 bar (11.4-17.1 PSI)

Gear type pump: 0.5-1.5 bar (7.1-21.4 PSI)

At 4000 RPM: approx 4 bar (56.9 PSI)

Relief valve opening pressure: 4.12-4.5 bar (58.5-63.9 PSI)

Gear type pump: 4-5 bar (56.9-71.1 PSI)

Here is one older thread - unfortunately it talks about potential defective new oil pumps.

http://www.bmw2002faq.com/component/option,com_forum/Itemid,0/page,viewtopic/t,295099/view,previous/sid,c8f312feba7bbcb672f9a0a554fe6e4d/

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Blue book spec chart for oil pressure:

Oil filter pressure relief valve opening pressure: 2.2 bar (31.3 PSI)

Oil pressure light illuminated below: 0.2-0.5 bar (2.8-7.1 PSI)

Oil pump pressures:

Idling speed: 1.8-1.2 bar (11.4-17.1 PSI)

Gear type pump: 0.5-1.5 bar (7.1-21.4 PSI)

At 4000 RPM: approx 4 bar (56.9 PSI)

Relief valve opening pressure: 4.12-4.5 bar (58.5-63.9 PSI)

Gear type pump: 4-5 bar (56.9-71.1 PSI)

Here is one older thread - unfortunately it talks about potential defective new oil pumps.

http://www.bmw2002faq.com/component/option,com_forum/Itemid,0/page,viewtopic/t,295099/view,previous/sid,c8f312feba7bbcb672f9a0a554fe6e4d/

Thanks so much Jim...great info! Looks like I'm dropping the pan and checking out that pressure relief valve on the oil pump.

Just ordered a bunch of parts from Blunt, guide rails, valve seals and guides, full gasket sets, etc, etc....time to get down to business!!!!

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You're welcome. Luis chimed in just before me with some good information.

BTW - oil pump parts are still available. I purchased a few items from BLUNT a few months ago for rebuilding a pump since they (the entire pump) are NLA.

I'm betting on a stuck pressure relief piston in the pump.

pics11108002.jpg

pics11108001.jpg

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