Dipstick Trivia
02-15-2015, 12:05 AM
#16
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As you know, I applied 3 not 2 O-rings because I did not have the plastic bushing it was missing. I applied a very thin film of the Loctite SI 5900 to each O-ring. Even without the bushing that I now have from Luis it has not leaked a single drop! It is bone dry I just checked. Still can't post pictures with either version of this pathetic App! I have typed this 3 times now. That is over a month now daily driven.
02-15-2015, 01:06 PM
#18
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Without extra O-rings, it wouldn't do much good to seal it. The tube is bolt to the intake, so it's not popping out, the oil is getting past the o-ring. Fingers crossed a slightly bigger o-ring with no crank pressure will do the trick. If not I'll start looking at other options...
02-15-2015, 10:42 PM
#19
Drifting
Tom, we made a nifty clip held on with a small/adjustable hose clamp. I'll take pictures when the axle work is settled with LR/DSS, as it's with a friend's shop in Phoenix dealing with what I stated was wrong from the start. We'll see how they decide to remedy faulty fitment of the CV's sent to me rated to 1000WT that don't fit the 968 trans cars.
I always thought that by pressing down on the dipstick tube when you tighten its bolt on the intake, that you could compress the o-ring and make it less prone to leaking. It never worked, but that's what I thought. So today I checked on an old motor and can confirm that pressing down on the dipstick will not help at all. See the picture below. The little ledge inside the pan recess is 6.5mm deep, which is a good 3.5mm deeper than the dipstick tube ledge can reach. That means there will always be a 3.5mm gap for the o-ring to sit in, no matter how hard you press down -- and of course the o-ring is nowhere near 3.5mm thick.
I'm going to try the stock o-ring and just vent the crankcase better (see epic crank pressure thread) and if it still leaks with no pressure, I will be in search of a better seal for the tube. Just adding an additional factory o-ring and pressing down might work, since the 2 O-rings together would be slightly thicker than the gap...
I know some use fancy RTV, but I am looking for a solution that can be disassembled and reassembled with ease, and without risk of getting RTV shrapnel in the crankcase.
And for you 3 liter guys running 951 dipstick tubes, be aware that the dipsticks for factory 3 liter motors extend into the pan deeper than the 951 dipstick and tube....
I'm going to try the stock o-ring and just vent the crankcase better (see epic crank pressure thread) and if it still leaks with no pressure, I will be in search of a better seal for the tube. Just adding an additional factory o-ring and pressing down might work, since the 2 O-rings together would be slightly thicker than the gap...
I know some use fancy RTV, but I am looking for a solution that can be disassembled and reassembled with ease, and without risk of getting RTV shrapnel in the crankcase.
And for you 3 liter guys running 951 dipstick tubes, be aware that the dipsticks for factory 3 liter motors extend into the pan deeper than the 951 dipstick and tube....
02-18-2015, 11:16 PM
#20
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I ordered some slightly bigger Viton O-rings from McMaster.
The size that fits best is:
9263K221 Multipurpose Chemical-Resistant O-Ring, Viton(R) Fluoroelastomer, 2.4MM Wide, 8.6MM ID
It's .4mm tighter on the tube, and .4mm tighter in the port, which makes a world of difference. It now feels the way you'd think it should. Time will tell how well it holds up, but the initial fit makes for a much more promising seal. They sell them in packs of 25, so I have spares if anyone wants to give one a try...
The size that fits best is:
9263K221 Multipurpose Chemical-Resistant O-Ring, Viton(R) Fluoroelastomer, 2.4MM Wide, 8.6MM ID
It's .4mm tighter on the tube, and .4mm tighter in the port, which makes a world of difference. It now feels the way you'd think it should. Time will tell how well it holds up, but the initial fit makes for a much more promising seal. They sell them in packs of 25, so I have spares if anyone wants to give one a try...
02-19-2015, 12:24 PM
#22
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PM you address and I'll put a couple in snail mail. I'm going to try just one, as it seems to be a nice snug fit. Haven't check to see if you could get the tube all the way down with two on there, even with pressure.
02-19-2015, 03:46 PM
#24
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02-20-2015, 05:39 AM
#26
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06-10-2016, 11:49 PM
#28
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