I lost all my oil without knowing it. The oil light went on but it was too late.
I believe all fuel and oil lines should be client with metal clamps.
This mechanic didn’t think it was necessary. Does anyone have a spare engine...LOL
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I believe that there should be NO barbed fittings with clamps anywhere on these engines if they have been "full flowed".
AN screw-on fittings are the only way to go, IMO.
There is simply too much pressure on the outlet side of the pump for barbed fittings to handle unless you have a pressure-limiting oil pump cover for your full flow system and even then the barbed fittings are marginal.
If you have a hydraulic shop near you, swaged or crimp hoses are an option. These have a working pressure rating of 4000-6000 psi.
AN or bust, literally. There is another current thread where this is detailed.
It is sad that those push-on fittings exist. They can't handle the pressure. Happened to me but I didn't blow the motor.
Yikes, all of my fittings are that push on type. Maybe I should clamp them all for now until I can replace them.
I did blow out my oil filter seal one cold night at start up, once.
The photo appears to show an AN fitting was used, but transitioned to a plastic barbed connector. Weak link?
My experience is not under a hood, so I’m ignorant here, but I do work in a rocket engine component test lab. We use AN exclusively in all of our permanent and temporary pressure test set-ups. (Well, except for the real high pressures where Autoclave or similar is needed - we go up to 40,000 psig and sometimes higher). AN fittings have limits, especially when something like a swivel fitting is used. We proof test all of our flex hoses and inspect/test them on a periodic basis. And in case you ask, our pressure mediums are helium, nitrogen or DI water, so not the same fluids this group deals with.
Again, I’m ignorant in this arena but my experience would have me running away from push-on connectors, especially when failure leads to nasty consequences.
Rubber hoses, when subjected to heating/cooling, eventually get hard and if you're not clamping them on the barbed fittings it's not if, but a matter of when a hose will let go. While the ends will get hard, the rubber liner inside can swell and restrict/cut off flow and take out the engine by oil starvation as well. It doesn't happen very often, but it is a (little) known issue with rubber lined hose. Clamps are essential, and a smart man on a budget will replace hose with new every 2-3 years.
Stainless hose with AN type fittings is, of course, much better, but remember, the inside is still rubber lined. I have also read about these hoses swelling shut- it doesn't happen very often, but just like the cheaper hose, it does happen.
A few years ago I read about a road race team with a modified 935 that had just rebuilt the engine (I can't imagine how much that cost!) and the thing died once warmed up and after only a few minutes of practice laps. It was taken out, checked over with new bearings and $$whatever else needed (oil pump? cylinder hone? a piston or 3? rings? a couple rods?$$) to get it up and running again. Re-installed and a few minutes into break in/practice laps it croaks again. Again it was taken apart and rebuilt. Thing was, nobody could tell why it was dying.
Anyway- after being stuffed back in the car it dies AGAIN! At this point they sold the engine (for pennies on the dollar) just to be rid of it. The guy who bought it went through it, found nothing that would cause what was happening so kept on looking and found that 1 of the stainless oil hoses that came with it had swelled shut.
If you're going to buy stainless hoses spring for teflon lined- it will never break down or swell shut. Some people claim that even rubber lined stainless is a regular replacement item and also say that with the teflon liner being slippier (vs rubber), there's less pumping loss (and more oil pressure). You'll have to have them custom made- the ends are swaged(? swedged? I'm too lazy at the moment to look it- mind you with the time it took to type all this I probably would have come out ahead! Anyway- you have to have the tool) on and teflon hose doesn't bend as tightly as rubber lined, but careful planning with the correct angle fittings will make it work. I have heard of guys having stainless hoses made up considerably cheaper at hydraulic equipment shops, but hydraulic fittings typically have very small openings because they deal with strictly high pressure (and relatively little fluid movement), where engines need oil FLOW as well as reasonable pressure. Hoses and fittings that don't flow what an engine needs can WILL starve an engine of oil as well.
Hope this helps. Al
I used to look up "hydraulic hoses" in the Yellow Pages (remember those?) for places local to me, and found a couple of great shops near me is several states. Now you can just Google the same search words, adding "near me". All of those shops like working on custom stuff, especially if you drive over there after installing their work to show them the car!
Generally, they charge $10 USD per foot for stainless sheathed hose (for Teflon - Rubber inside is a bit less) and then $10 USD per end fitting. At least that's a good rule of thumb. I've also found that a lot of local NAPA stores can make up custom hoses, too.
You can get around the fact that Teflon hoses don't like to bend much by using angled fittings and watching the route the hose has to take. Fittings come in straight, 22.5º, 45º and 90º angles.
@JPC Why did you start a new thread to tell us about the same problem? If you’re still in Arizona @PaulEllis told you to go to Competition Engineering and they will either fix your motor or get you a new one and probably fix your fittings.
Actually I just checked your other thread and you said CE was going to build you a new motor.
Good point, Robert...
Just a thought, don't trust idiot lights. Install an oil pressure gauge and watch it as you drive. I lost an oil hose once because I didn't tighten the clamp enough after my first time changing the oil (I pumped the previous owner's oil out of the cooler hoses and replaced it with fresh 20W-50 Wolf's Head loaded with ZDDP). I noticed the pressure drop right away, long before it reached the 7 PSI setpoint of the idiot light, and shut her down. The only loss was a couple of quarts of oil on the driveway.
This discussion has taught me something. I didn't realize how high the pressure is at the back of the pump, I figured it was similar to the 60 PSI I read on the gauge when the engine is cold. I'll move replacing the rubber hoses with steel lines, stainless steel braided Teflon hoses, and AN fittings up higher on the to-do list.
Same, same but different. A few weeks ago my brake pedal suddenly went to the floor. I could tell that there was resistance and that brake fluid must be spraying somewhere. One of my rear braided lines had suddenly failed. Apparently brake fluid burns like gasoline. The fluid sprayed on the exhaust causing a fire. When the fir reached the engine compartment that new fire suppression gizmo deployed and prevented more serious damage to the engine.
Competitive Engineering, Wood Street, Phoenix, put on this oil hose. Dan said didn’t need clamp..Look at pic no indent where ramp was to be..
You guys feel he should be liable? I am not holding my breath. I had 500 miles on at most on this new hose
I've always seen the brass barb fitting with 4-5 actual barbs with sufficient space for a hose clamp.
AN Fitting have the (red) sleeve that hold the hose vs the clamp-
I clamp everything. Check regularly. So far so good.
I constantly check the mirror for smoke.
@PaulEllis posted:Same, same but different. A few weeks ago my brake pedal suddenly went to the floor. I could tell that there was resistance and that brake fluid must be spraying somewhere. One of my rear braided lines had suddenly failed. Apparently brake fluid burns like gasoline. The fluid sprayed on the exhaust causing a fire. When the fir reached the engine compartment that new fire suppression gizmo deployed and prevented more serious damage to the engine.
WTF!!! Glad to hear your okay Paul. I hope you’re painting it yellow again. Love that color.
i lost an oil hose on last VS, was too close to exhaust header when the clamp broke, BOOM it was instant major oil cloud, killed engine and coasted, no damage or fire....fire i would have been srew,...unlucky..
Thanks Robert. Yes, staying yellow. I had just spent a thousand bucks on a ceramic coating that is now half burned off. I think I'll get a clear bra this time.
@JPC posted:Competitive Engineering, Wood Street, Phoenix, put on this oil hose. Dan said didn’t need clamp..Look at pic no indent where ramp was to be..
You guys feel he should be liable? I am not holding my breath. I had 500 miles on at most on this new hose
What kind of mechanic would 1. not put a clamp on that assembly, and 2. use that assembly in the first place?
I would certainly claim it was the shop's fault.
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