Sensor on back of Intake manifold.....

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ericinga
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Sensor on back of Intake manifold.....

Post by ericinga »

I'm drawing a blank on this one.

Back of the intake manifold next to the distributor is a short metal manifold. There's an oil line feeding it. The sensor connected to the small manifold is dripping oil and needs to be replaced. It is not the large oil pressure sender. It's roughly the diameter of a quarter with a spade connector attached to the tip. It is bronze with with a plastic insert.

Which sensor is this?

Eric
Eric Spies
1989 32 SDFB
Twin 318s
Lake Lanier, GA
Marinette Boat
EWRice
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Re: Sensor on back of Intake manifold.....

Post by EWRice »

Sounds like your oil alarm switch. Grounds out to activate a light, buzzer, bell, etc if the oil pressure drops below a certain pressure. Very common part at any auto part store. Very common to start leaking after so many years. Might even be a part number stamped in the steel body.
Muskegon Lake
1972 32' Express flybridge
"AL13"
Twin 318s
On board air & prime 920
1963 Thompson Super Sea Lancer
Graymarine 327
1961 Alumacraft 12'
'55 10hp Johnson
Joe
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Re: Sensor on back of Intake manifold.....

Post by Joe »

Some used a switch for the alternator.
1988 sedan flybridge. Black / White. 318 240 hp Aluminum aft deck hard top. Louisville Ky . Tartans landing. " KNOCKEFELLERS"
Fastjeff
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Re: Sensor on back of Intake manifold.....

Post by Fastjeff »

It's the oil pressure sensor. Look for an early (1980s) era Mopar 'idiot light' switch at NAPA or elsewhere. (Tell the counter dude the switch is for a LIGHT, not a sensor.) And buy two: mine ate at least one a year!

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
ericinga
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Re: Sensor on back of Intake manifold.....

Post by ericinga »

Thanks Jeff.

I found them last night at Autozone for $10 EA. Just bought a 32 and will replace all 4. I assume it's two per engine due to dual station.

One of them literally spurts oil with every pump stroke. The PO allowed it to make quite a mess of the bilge.
Eric Spies
1989 32 SDFB
Twin 318s
Lake Lanier, GA
Marinette Boat
Fastjeff
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Re: Sensor on back of Intake manifold.....

Post by Fastjeff »

POs! Sheesh!

Jeff (former PO)
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
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bill
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Re: Sensor on back of Intake manifold.....

Post by bill »

BigM
Congrats on the new boat Eric. :)
bill
Former owner of
ALUMINATION
Grosse Ile MI
Located on LakeErie
37' F/B Sedan
1975
Twin 360 Chrysler Marine
Raw water cooled
Hydraulic steering both helms
USCG Master Lic. Retired[/color]
Third Owner bill
ericinga
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Re: Sensor on back of Intake manifold.....

Post by ericinga »

Thanks Bill.

Cosmetically, she's 85-90%.
Bilge has been a nightmare of oil and dirt. I spent 4 hours this weekend wiping down the motors with Dawn and water. They were black. Made it hard to track down the oil leaks. Valve cover gaskets and an oil switch fixed the leaks.

The engines are sound but need TLC. Engine vacuum is a constant15 PSI + and compression is 130+ and even. One carb rebuild to go. Thankfully, the ignition system tested fine.

Eric
Eric Spies
1989 32 SDFB
Twin 318s
Lake Lanier, GA
Marinette Boat
Fastjeff
Site Admin
Posts: 1521
Joined: Sat Jul 12, 2014 5:06 am
Location: Rock Halll, MD

Re: Sensor on back of Intake manifold.....

Post by Fastjeff »

One thing I never got right on my 32 footer (as the new owner will attest) is cleaning that damn bilge. I scrapped Black Crap until I was black in the face; I used solvent, and once even tried oil absorbent. (What a mistake; it rained overnight and....) It still looks like crap.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
Wilfred
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Re: Sensor on back of Intake manifold.....

Post by Wilfred »

Found an oil leak that scared me, yes the oil alarm sensor the culprit.
Also found the PO had stuffed toweling in the area to absorb the oil
Not as bad as the water pump he mounted with one bolt!

I have an S310 as replacement..does that sound correct?
W. J. Brockman
1984 Marinette Express Bridge
Twin 318s 235 hp
Bolles Harbor, Michigan
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