0360 180 High Oil Pressure

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campertop
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0360 180 High Oil Pressure

Post by campertop »

On startup at idle im about 65-70lbs, once warmed up idle is 60lbs. Cruise RPM and im well over 100lbs and blowing seals. No spacers in pressure relief valve, and ball and spiring seem fine. Any ideas?

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kwanjangnihm
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Re: 0360 180 High Oil Pressure

Post by kwanjangnihm »

campertop is this a new issue that just started? how many hours on this engine?
He'll cut your throat, baby, stick you in the back, drive off in your Cadillac.
He's more trouble than you think, he'll kill your sugar, leave you in the drink.

campertop
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Re: 0360 180 High Oil Pressure

Post by campertop »

Not a new issue, been like this since i bought the boat. No idea on engine hours.

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Slidin Gator
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Re: 0360 180 High Oil Pressure

Post by Slidin Gator »

Restriction in the relief passage back to sump, a restriction between vernathane and relief or the wrong spring (too heavy) in the relief. I would crank it to oil everything up and then remove ball and spring. Oil pressure near zero says it’s the wrong spring. High pressure says a plugged passage. Idle should be around 45.

What seals are blowing? This would help figure out what passage is plugged (before or after relief) if it is not the spring.

If the blockage is upstream of the relief, the bearings have been starved. But no mention of high temp, so my bet is a restricted relief dump to pan passage or the wrong spring.
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.

GMAC 76
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Re: 0360 180 High Oil Pressure

Post by GMAC 76 »

do you use an electric gauge with a sending unit or a true pressure gauge?

campertop
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Re: 0360 180 High Oil Pressure

Post by campertop »

Thanks, will check spring tomorrow, fuel pump seal, crank seal, and the block off plates seals on the back of motor.
This is with a manual gauge, was reading same with electric gauge.

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Slidin Gator
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Re: 0360 180 High Oil Pressure

Post by Slidin Gator »

The seals that you mention are not directly exposed to oil pressure. I tried to upload an oil system diagram for your engine, but picture uploads seem to be blocked at the moment. Look at the oil system diagram in the manual on this site at the following link for reference:

https://www.southernairboat.com/pdf/air ... educed.pdf

Blowing the seals you mention are related to high crankcase pressure, not oil pressure. Check your blow by hose, this would not be the first time that dirt dobbers plugged up a crankcase vent hose. It is also possible that you have excessive blow by due to worn rings or even a hole in a piston, but you would be seeing high oil temperature with those conditions.

Oil pressure ultimately goes back to the sump via leakage out of the bearings, rocker arms etc. The accessory case gaskets and main crank seals do not see the 100 PSI oil pressure you describe, there is no way they would ever withstand that.

Oil pressure inside the motor is referenced to sump/case pressure while your gauge is referenced to atmosphere. Say your oil pressure relief is set to 75 PSI, that is the difference between Pump output and the inlet (sump/case pressure). If case pressure is 25 psi, your gauge would read 100 PSI. Resolve the case pressure issue and you should see your oil pressure gauge readings drop.
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.

campertop
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Re: 0360 180 High Oil Pressure

Post by campertop »

Interesting info, Thanks for helping understand

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Slidin Gator
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Re: 0360 180 High Oil Pressure

Post by Slidin Gator »

You are welcome, let us know what you find.
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.

GMAC 76
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Re: 0360 180 High Oil Pressure

Post by GMAC 76 »

does the oil pressure adjustment assembly adjust internally with shims in the housing behind the spring or externally with an adjustment screw and lock nut

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Re: 0360 180 High Oil Pressure

Post by BobBrack »

Lycoming makes both types.

campertop
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Re: 0360 180 High Oil Pressure

Post by campertop »

GMAC 76 wrote:
Fri May 15, 2020 9:14 am
does the oil pressure adjustment assembly adjust internally with shims in the housing behind the spring or externally with an adjustment screw and lock nut
Mine adjusts with washers.

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Re: 0360 180 High Oil Pressure

Post by campertop »

Ok, Finally got time to mess with boat, with spring and ball removed oil pressure is at 15-20lbs idle, so does this mean i need the low pressure spring and the wrong one is in there now?

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Slidin Gator
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Re: 0360 180 High Oil Pressure

Post by Slidin Gator »

Have you checked your crankcase vent to see if it is flowing?
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.

campertop
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Re: 0360 180 High Oil Pressure

Post by campertop »

Yes, vent is clear and flowing. Also, oil cooler bypass plunger was stuck down and spring bent, so that was not functioning if that will cause any pressure issues. Started pouring and have not ran after pulling plunger.

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Slidin Gator
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Re: 0360 180 High Oil Pressure

Post by Slidin Gator »

campertop wrote:
Sun May 24, 2020 6:33 pm
Also, oil cooler bypass plunger was stuck down and spring bent, so that was not functioning if that will cause any pressure issues.
Yep, as long as you are saying the Vernathane is stuck closed, correct? If that is the case, all oil flows through the cooler so the oil never comes up to temperature. Here is a screen shot of the oiling diagram, wish it was clearer.

Image

Back to the start of the thread:
campertop wrote:
Tue May 12, 2020 7:53 pm
On startup at idle im about 65-70lbs, once warmed up idle is 60lbs. Cruise RPM and im well over 100lbs and blowing seals. No spacers in pressure relief valve, and ball and spiring seem fine. Any ideas?
65-75 PSI idle oil pressure is not out of the ball park on cold start up, specs show 115 during warm up, which usually requires some revs. 60 PSI idle is high unless the oil is cold, what oil temp do you see once warmed up, I'm thinking it barely moves the gauge??

Rev a cold Lycoming and oil pressure will well peg a 100 PSI gauge easy, note that warm up oil temp is 115 F.

Put the relief back together, the bearings starve without it (which is why I said to oil up the engine first). That is just supposed to be a quick test.

From what you have found I would be ordering a new (used) Vernathane, but if you need to prove it before spending the dough, my next test would be to pull the vernathane and try. This will put the oil system in bypass mode, so the oil cooler will not work, oil should come up to temp and keep climbing. As temp rises, oil pressure should drop and you should see something in the range of 25 PSI idle with oil temp between 180-220. Max pressure at RPM and operating temp is supposed to be 55-95 PSI, so a pegged 100 PSI gauge with cold oil is good. Shut it down once you get to 230 F or so.

Image
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.

campertop
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Re: 0360 180 High Oil Pressure

Post by campertop »

This motor does not have a vernatherm, it has the spring and plunger above the oil screen on the back of the motor.

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Slidin Gator
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Re: 0360 180 High Oil Pressure

Post by Slidin Gator »

The spring and plunger system is similar. Stuck closed and all oil flows through the cooler making warm up difficult. Stuck open and oil bypasses the cooler.

https://www.lycoming.com/content/understanding-oil-flow
In each of the two basic systems, there is a valve which forces the oil through the oil cooler when the valve is seated or allows the oil to bypass the cooler when the valve is open. Lycoming Engines were originally equipped with a bypass valve which was controlled by a spring. Referred to as a spring and plunger type, it functioned as a result of the amount of pressure in the oil system. The spring-controlled bypass system was superseded by a system controlled by a Thermostatic Oil Cooler Bypass which reacts to oil temperature changes.
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.

gso480jr
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Re: 0360 180 High Oil Pressure

Post by gso480jr »

Found my plunger stuck down so bad it took a right angle pick to pull it out. Resurfaced it and cleaned everything out. Seems to slide free now. I'm chasing a problem with oil consumption. 4 qts to 15 gallons of AVGas, ouch! Maybe I just came across the problem?

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