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oil pressure gauge line.

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tahoe healey

tahoe healey

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The area around the braded cable line between the block and the line to the oil pressure gauge has been looking like apossible leak point. I've tightened the couplers with no improvement. I just purchased a new one from British Car Specialist in Stockton,CA. The question is do they get a sealer? There is the piece that goes into the block that I can probably use teflon on but the cable has fittings that have a ball kind of thing which looks like it just compresses with tightening the nuts. Is that it or should some kind of sealer be put on it?
Thanks.
 
Beg to disagree with Dave, but I use PST [pipe sealant with teflon] on all metal-to-metal joints, it's like insurance-you only need it when you have a problem. And as my Dad would say - the best way to solve a problem is to do your homework and avoid it. I use PST [ Locktite is a brand usually available at hydraulic coupling suppliers ]on all fluid joints because I don't like leaks, weeps or what ever you want to call them.
I had a similar leak on the same oil line at the block end. I put a wrench on it to tighten the joint and sheared off the flair nut shoulder on the hose end piece, making the flex line garbage. A new line, PST and moderate torque = tight joint.

Regards, Bob
 
Absolutely, emhatically Techically No tape or sealant is required RF Thom.---Keoke /ubbthreads/images/graemlins/nonono.gif

N besides some of these folk just might ingest some of that PFE sealant into the guage or oil system if used elsewhere and really cause a problem. /ubbthreads/images/graemlins/yesnod.gif
 
Can PST be found at Home Depot? I'm not familar with it. Plumbing department?
Thanks for the imput. It is a difficult place to get to and I don't want to bleed the gauge any more than I have to.
 
Bob,
Whatever works for you.

TH,
Not sure that you even need to bleed the gage. After all, pressure is pressure whether it is oil or air. Actually some air in the line acts as a compressible shock absorber & reduces gage flutter.
D
 
[ QUOTE ]
Can PST be found at Home Depot?---YES I'm not familar with it. Plumbing department?--OF Course its for plumbers
Thanks for the imput. It is a difficult place to get to and I don't want to bleed the gauge any more than I have to.You don't have to bleed it at all---Keoke /ubbthreads/images/graemlins/laugh.gif

[/ QUOTE ]
 
Normally, I'd use the ptfe, teflon, pipe dope, permatex, thread sealant on threads or gasketed surfaces only.
The two machined surfaces of the flex line and fitting shouldn't require any sealant on them. There really is no proper place to put the sealant at the flex line junction.
 
LGalper, that sounds like a safe way to go.---Keoke /ubbthreads/images/graemlins/thumbsup.gif
 
[ QUOTE ]
There really is no proper place to put the sealant at the flex line junction.

[/ QUOTE ]
Hi Lou,
I certainly agree, the sealant just makes a mess.
D
 
OK, good. No sealant. Thanks.
I've always blead this darn thing. It's not hard, just can get messy catching oil pumping while turning on the engine. If I don't bleed there will be about 10 inches of air in the line at least. Won't that effect the accuracy? I know pressure is pressure. But air is more compressable than oil or we wouldn't need break fluid. Is it that it would just take moments longer to get a pressure reading as the air volumn is compressed? Please excuse my ignorance. This is not in my field of education.
 
[ QUOTE ]
Is it that it would just take moments longer to get a pressure reading as the air volumn is compressed?

[/ QUOTE ]
Yes - the gage will take slightly longer to respond to pressure changes either up or down. Sometimes there are pulsating pressures in the oil system that just vibrate the gage needle up & down a bit. This only wears the delicate gage internals more than necessary. A little damping helps & most modern gages have a very small bit of delay. Some have a whole lot. Maybe too much. Just like you wish that the fuel level gage had. Just a personal preference.
D
 
Keoke

Have you noticed that your daily driver never leaves a mark on your driveway anymore - that's because when the pressure got applied to stop it, the automakers started using, you guessed it newer anerobic sealers EVERYWHERE. Many of the fluid joints had 'pre-applied' sealers incorporated in their specifications. Anerobic sealer, which cure in the absense of air, are pre-applied to seal joints incapsulated in a paint like carrier, so as shelf life became a non-factor. Fuel lines, oil cooler lines, power steering lines, heater hose fittings, even vacuum fitting - all had this technology added to their specification. Yes the joints should not require any sealer but like I said it's cheap insurance, and it works. Even Oil Gallery Plugs which utilize dryseal tapered NPT [Nation Pipe Threads] were enhanced with anerobic sealer. The 'white glove test' became manditory. That's right the final inspectors went over the vehicle under hood with white gloves and you don't want to be the source of a stain - it usually is painful.

Regards, Bob
ps. I'm a Retired Resident Product Application Engineer [37 years] for an Engine Manufacturer [ 4,000 units / day, which ended up being 4,000 vehicles / day].
 
Thom:
IF that is the case now I know why the quality is considered to be so low they have been gluing these things together instead of asssembying them usung good engineering practice---Keoke /ubbthreads/images/graemlins/grin.gif
 
Bob,

I'm partial to using Hylomar on threaded and gasket surfaces exposed to oil. Seems like a better suited product than Pipe Sealant with Teflon for automotive applications. The anerobic sealer technology sounds interesting. Is there something on the market that can be applied by the mechanic (rather than during the manufacture of the product)?

Cheers,
John
 
John

PST sealer is in essence liquid teflon tape. Note that you can never force searler into a joint - but you can squeeze excess out. That's why you apply the sealer to the joint mating sealing surfaces, which sometimes is not the thread.
There ia 0.005' rule. Joints with gaps over 0.005" utilize RTV sealer as this material has excellent elongation but low shear strength. As a side note acid base sealers seem to do a better job here because the acid given off in the curing process tends to etch the surfaces of any foreign fluids, increasing the adheasion properties. For joints under 0.005" gap use anerobic sealer which has high strength, and low elongation properties. In the subject joint you are trying to fill leak paths under 0.0005" which is the roughness of a general machined surface, so you don't need much material. Sealers are parallel to soldering. A good clean mechanical joint will be enhanced with solder. Try to solder two oily wires laying side by side - poor joint. Sealers are the same they need a good clean mechanical joint.

Regards, Bob
 
Hi Bob,

Thanks for the info. I have moved away from using RTV sealers because it can be such a pain when disassembling something and cleaning up the parts (unfortunately, the P.O. loved using the stuff). That's one of the things I like about Hylomar, it never cures. Does the PST sealer create any problems for disassembly?

Cheers,
John
 
HI John, Yes there is an anerobic product on the market you can use it is listed as Locktight 515. It is not messy but it is designed to seal tight.--FWIW---Keoke
 
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