Fuel In Oil

CAPTKEV85

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1977 Mercruiser 470 4cyl Fresh Rebuild Ran The Motor For About 6 Hours On Land Never Put A Load On It Yet. I Had A Timing Issue In The Begining. Thats Fixed. She Runs Like A Champ. But I Notice The Blow By Tube When I Rev It Up Is Shooting Oil Out Of It. Once This Happens My Oil Pressure Drops To 10 Pounds And The Lifters Are Clackin. I Shut The Motor Down. Drain The Oil And It Was Like Pure Gas. It Was So Thin I Guess The Lifters Couldnt Prime Therfore The Ticking I Had. I Drained The Oil And Put Rotella 30 And Oil Pressure Came Up 40 Pounds. Another 3 Hours Later It Did It Again. Plugs Are Black As Hell But The Carb Was Just Rebuilt. The Timing Is Not Set To Factory Spec Yet. So Im Hoping Thats The Prob. I Was Also Told To Put The Boat In The Water And Put A Load On It So The Rings Can Break In. Any Info Would Be A Great Help !!
 

Bondo

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Re: Fuel In Oil

Plugs Are Black As Hell But The Carb Was Just Rebuilt. The Timing Is Not Set To Factory Spec Yet.

Ayuh,.....

Rebuilding a Carb is only the 1st Step,.... It's Still gotta be Tuned to the motor......
If you still have Gas in the Oil, After you finish Tuning the Carb,....
I'd Guess the Fuel Pump is Shot.....
 

Don S

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Re: Fuel In Oil

She Runs Like A Champ. But I Notice The Blow By Tube When I Rev It Up Is Shooting Oil Out Of It. Once This Happens My Oil Pressure Drops To 10 Pounds And The Lifters Are Clackin. I Shut The Motor Down. Drain The Oil And It Was Like Pure Gas.

You need a fuel pump. A carb on a running engine couldn't put that much fuel in the oil anyway.
If you are getting so much blow by that oil shoots out of the dipstick, I would be wanting to find out why. Does it do that with fresh oil? Or just when it's overfull with gas in the oil?
 

CAPTKEV85

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Re: Fuel In Oil

When The Motor Has Fresh Oil Its Fine But After A Couple Of Hours And It Has Fuel In It Thats When It Starts Shooting Out Of The Blow Tube
 

Don S

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Re: Fuel In Oil

Replace the fuel pump put in new oil and filter and give it a try.
 

CAPTKEV85

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Re: Fuel In Oil

Ok Thats Y She Runs Crappy At An Idle But Perfect Above 1000 Rpms. Also My Lawn Is Black From The Exhaust. The Carb Was Redone And Checked And It Is Up To Spec. The Fuel Pump Looks Like Original Pump.
 

Bt Doctur

Supreme Mariner
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Re: Fuel In Oil

do you see and liquid in the clear hose that runs up to the carb from the pump.
a sign the diaphram is ruptured
 

CAPTKEV85

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Re: Fuel In Oil

No I Do Not.i Have A Strong Feeling That Were The Pump Goes Into The Side Of The Block Is Leaking Right Into The Oil. When The Motor Is Running I Look Down Into The Carb And Its Not Pouring Fuel In It. Just A Steady Flow Of Fuel
 

Bondo

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Re: Fuel In Oil

Make darn sure you geta MARINE fuel pump, NOT auto!!

Hmmmmmm,....... I can't think of Any cars that ran the Mercruiser 470s,..??..??......:D
 

Coors

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Re: Fuel In Oil

No I Do Not.i Have A Strong Feeling That Were The Pump Goes Into The Side Of The Block Is Leaking Right Into The Oil. When The Motor Is Running I Look Down Into The Carb And Its Not Pouring Fuel In It. Just A Steady Flow Of Fuel

A lot of gas in the oil, might want to replace pump, start it; check that is is ok.
Then change oil again.
And quick, new parts don't need oil thinned that- aways.
 

CAPTKEV85

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Re: Fuel In Oil

I Ordered A Marine Pump For 100.00 I Should See It On Sat But New York Has A Crappy Weather Forecast
 

Scaaty

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May 31, 2004
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Re: Fuel In Oil

Hmmmmmm,....... I can't think of Any cars that ran the Mercruiser 470s,..??..??......:D
Come on Bondo..ya know darn well what I gave was good generic advise, as I have not, and never will see a 470. Aint the faintest whats involved in the pump...
That said...more than once I have been at the counter auto store ...(take yer pick of any...billion boats here Puget Sound too)..some fool..and seen the catalog out with the stupid kid on one side, fool on the other side..overhear the comment...
"Damn boat store wants over $100...I see them here $19.95"
Ya gotta dumb down here sometimes...and no way in hell discrediting yer priceless knowledge...ya know what I mean....be well..mean it too..:cool::D
 

Bondo

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Re: Fuel In Oil

ya know what I mean....be well..mean it too..

Ayuh,...
I know you're just post padding to get rid of the Rear Admiral handle,.....:D
And the good generic comment is well placed,+ quite True.....

I just had to Jump on the Funniness of the moment..........:D ;)
 

Scaaty

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Re: Fuel In Oil

Ayuh,...
I know you're just post padding to get rid of the Rear Admiral handle,.....:D
And the good generic comment is well placed,+ quite True.....

I just had to Jump on the Funniness of the moment..........

Not a prob, and ya know it...(whats that head banging noise I hear??..(Don...??:eek:)
He's now PNW on the coast Ocean Shores after Alaska..seems brought the weather with him one last "toast"...(coast has SNOWY beaches today!)
I'm back in bottom Puget Sound (Steamboat Island Peninsula tip about 60 miles east from him))...and now I'm afraid to ride the Harley to the beach there for rally's...seems he will spot me and say.."YOU"...your that Scaaty "know it all dude..(I DO think he's that good!)
HA!!!
Do believe I can find him some day with internet (easy..I know the area well...and his posting of his new digs, and last homes for bought.. says .."thats him!.!!"), and if he ever see's a big old Red Harley Bagger, or my 150hp Honda sportbike parked out front, me crawling on up the drive, saying "put the weapons down..its ME..SCAATY!..BOOM..hope he misses!...on my knee's.." Genuflecting "..saying a simple thanks.
Dude knows his "stuff"...
I like cranky old farts that know it all...and Don (and he DOES!) has more in that brain of his than us all..(or least top 1%)
Reminds me of my dad...as a kid building Minibikes 50 years ago..."this will work!..dad said .."ya should do..(insert whatever)...I said .."nah..thiis well work!.. Dad would walk away and say zip....then I learned a REAL hard, painful "lesson"...in how things work!:eek:
OUCH!!!...(told ya dumbas kid..)
Don...love someday to buy ya a late lunch at that "Chicken/Seafood" small restaurant (left side heading for the beach off the "109" in..go straight past..its then "Sun and Surf"..right side the big hotel.."..main drag in, not a left to the "masses" intro part.)
Many do not know that Washington beaches are "designated highways"
Ya can pull in on the beach by Don, and drive ..(WATCH THE TIDE!!!). and drive all the way north to Pacific Beach...(carry gas if ya did not fill up!).long way.
And Ocean Shores, 4th July....big beach fires..great people and great times!...millions dollars "works" bought off the "Indians (ask for the stuff under the "counter!")..(damn, I letting to much out here Don?...)
My take is if ya wake up..something will tick ya off...if ya don't..problem solved....always gotta remember.."stupid"...is right around the next corner..
:D
(oh yeah. am I that close to 5000 post? (rear admiral???...hmm, 4 years now here..) Never bothered to look..(like I have been too busy watching TD..(thanks for telling me too slow down on "spouting off" TD) trying to catch JB..(which is the "master" !!
Ya guys are all the best,.. and the "gratitude"..of "free knowledge"..passed on....cannot be expressed on a "key board"...
Aint no frigging "manual"..in the world, that will ever hold you people's "knowledge"..damn...the 9 million page tax code has nothing on you guys..and done a lot quicker!
With..(always)..Respect to ya old wrenches...(Robby..living too close to Don..gotta watch my info stuff now!!...(insert a big "thanks" grin here..again...knows his stuff..LISTEN too him!!!..(thanks from me Don too by the way..VP 280 had a crap (milky oil..sitting 12 weeks slip)..that damn oil fill junk crummy gasket..did 10 pounds after PSI...found it..good to go now..but I did buy all the gearcase/prop seals, and shifter seals...THANKS for the info.. and mean it..owe ya .. be well.."all"..ya da best!
(oh yeah...one more thing..can't stop with out saying thanks Bob ("laddies"...old Tower of Power Freak...knew Carl K personally....nice old VCR tapes old boat racing!!!..send them on after a finish watching..Scott..(Chinewalker..you would love'em..old time CRAZYS!...get me a PM, and send then to ya)..FR on old Johnny's, oh hell, ya know who ya are..."thanks"..and mean it...
 

sdshort1979

Cadet
Joined
Mar 25, 2008
Messages
8
Re: Fuel In Oil

I would rebuild the carb again...sounds like the float is'nt set right or sticking open, which would explain why you are getting fuel in the oil
 

CAPTKEV85

Petty Officer 1st Class
Joined
Mar 12, 2008
Messages
229
Re: Fuel In Oil

Fuel Pump Is The Problem. As Soon As I Pulled It Off The Block Fuel Poured Out Of The Pump I Had 6 Quarts Of Fuel/oil In The Pan. Motor Takes 5 Quarts. I Put The New Pump In New Oil And The Boat Runs Like A Champ. Now I Gotta Prep Her For The Water. Striper Season Starts In 2 Weeks And Its Time To Fish. Thanks For All The Help Guys!!!!:)
 
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