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Compresion drop in the last year

Old Jun 10, 2010 | 12:20 PM
  #26  
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I didn't say the 'w' stood for Winter (although it did per the SAE's initial classification).

The first number is the dynamic viscosity, how the oil behaves at a very low temperature. Especially interesting is to what temperature the oil is still flowing to the oil pump by itself. E.g. “5W” means that the oil still flows at minus thirty degrees Celsius.

I too run 5w30 (Castrol GTX), year 'round.

edit: that's it, BHR gets deleted from my "good guys" list! (j/k)

Originally Posted by Flashwing
Oh Denny you were so nearly there! You are right on the money that your engine temperature and overall internal environment doesn't change regardless of what the ambient temperature is. Therefore, because oil is thickest when the motor is cold you want a viscosity at startup that is as close as possible to the viscosity of the oil when the motor is up to temperature. 20w/50 is like pushing honey through your motor.

Castrol GTX 20w/50 cSt @ 40 degrees C: 143.1, @ 100 C: 18 (Spread is 125 cSt)
Eneos 5w-40 (which I run now): cSt @ 40 degrees: 82.5; @ 100 degrees: 14.0 (spread is 69 cSt)




No, the "W" is an indication that the oil is a multi-viscosity oil. There is no winter rating for any oil.



Marc, if you need more information let me know and I'll take care of you.

Last edited by Huey52; Jun 10, 2010 at 12:59 PM.
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Old Jun 10, 2010 | 12:44 PM
  #27  
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Todd are you talking about these: (thanks nycgps for the img and the purty writing)

I'll give it the week and do a compression test next weekend. I'm also gonna have to wait until then to change the plugs as I'm waiting on my BHR order to ship!
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Old Jun 10, 2010 | 12:56 PM
  #28  
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10w -40 does it for me I am seeing 18-19 for vacuum I was gonna try 0w-50 rp
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Old Jun 11, 2010 | 07:45 AM
  #29  
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So I went and bought the zoom power cleaner today... Canada gets "hosed" again (pun intended): we don't get that 2'-3' long hose that the US guys get with the aerosol can. We get a tiny stubby like the one that comes with a can of WD-40.

You'd think that this would be something easy to track down, but apparently no one sells aerosol hoses...

I am thinking I MIGHT be able to get to those vacuum nipples with the shorter hose if I go from the bottom but I am on the lookout for a longer hose. If anyone has any pointers on where to source that -- especially locally -- that would be awesome.
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Old Jun 14, 2010 | 08:23 AM
  #30  
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Ok so Seafoam done :D

http://www.youtube.com/watch?v=aLDgU...layer_embedded

I did notice however that after that I have a vacuum leak somewhere near the UIM. It's only noticeable after the engine is hot but it's pretty loud. This is gonna be fun to track down...
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Old Jun 14, 2010 | 08:24 AM
  #31  
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Dumb question, but did you make sure to put the vacuum caps back over the nipples?
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Old Jun 14, 2010 | 08:39 AM
  #32  
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lol yes, that is the first thing I checked.

Actually with the 06+, there are vacuum tubes attached to the nipple with a T connection running to the oil case. I made sure they were re-attached.

The leak actually seems to be coming from the middle of the top of the UIM somewhere...
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Old Jun 14, 2010 | 09:26 AM
  #33  
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probably from the vacuum box area where the purge etc all go to?

an healthy engine will have 18-19 of vacuum. 17 is ok. at 16 its time to start thinking. it will run ok but there is a good deal of wear.

As for as oil goes-- do a good search in this forum. Mazmart/BHR/RR and a bunch of others have contributed to the discussion. Pressure/lubrication and viscosity's have all been talked about. Look at some used oil analysis's and see which oils are maintaining their viscosity.
hope the carbon cleaner works for ya!
rotor on dudes
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Old Jun 14, 2010 | 09:37 AM
  #34  
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OD,

Is measuring the vacuum from those ports a viable alternative to a compression tester? I know that they are related, but not quite the same thing, but it seems that a constant vacuum gauge there might be a reasonable way of knowing when it's time to take it in for an official compression test, without the more expensive digital compression tester.


This accurate?
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Old Jun 14, 2010 | 09:59 AM
  #35  
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Originally Posted by olddragger
probably from the vacuum box area where the purge etc all go to?
Do you have a visual for the "experience impaired"?
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