Fuel in the oil? - Great Lakes 4x4. The largest offroad forum in the Midwest

jeepfreak81 · April 2nd, 2006, 02:50 PM

Is it possible for a mechanical fuel pump to be bad and dump gas into the crankcase??

I pulled my dipstick and had an awful lotta gas in my oil....

vwBOY · April 2nd, 2006, 03:26 PM

same thing happens with my buggy
does your tank sit higher then your pump if so get a valve so when you arent using it turn the gas off
after i did that no more gas in the oil

Captain Ledd · April 2nd, 2006, 03:33 PM

In the technical term of "possible" yes. But I don't really think so. Was it used for really short trips and the engine not particularly warmed up alot? That will make oil reek of gas. I think if it's running rich it will get some gas in the oil.

How much are we talking about though? Like the level on the dipstick was way higher than the full line because of gas added? or did it just stink like hell of gas?

clarkstoncracker · April 2nd, 2006, 03:38 PM

sounds like a bad diaphram in your fuel pump. Anytime you have alot of unburned fuel in the cylinder, you will get some in your oil. was there anytime recently you were cranking the hell out of this thing, and it didn't start?

That gas left in the cylinders will just go into the crank case.

jeepfreak81 · April 2nd, 2006, 03:46 PM

Quote:

Originally Posted by clarkstoncracker

sounds like a bad diaphram in your fuel pump. Anytime you have alot of unburned fuel in the cylinder, you will get some in your oil. was there anytime recently you were cranking the hell out of this thing, and it didn't start?

That gas left in the cylinders will just go into the crank case.

yep there was, on 2 occasions over the winter, friggin thing wouldnt start, but the level on the dipstick was higher because of it. Oil looked runny coming out too. Fuel pump is brand new from NAPA, not that it matters, but it has less then 100 miles on it, Im sure its possible the diaphragm could be bad already.

This is a fresh rebuilt 355 with under 100 miles on the whole motor.

right now it wont roll over, i think the BRAND new starter has a bad solenoid

Yetti · April 2nd, 2006, 06:34 PM

rip the fuel pump off and check it from the lever side, its most likely the reason you have fuel in th oil. the only other way is to over fill the float bowl while it sits for a long time. it can wipe out the bearings so change out the oil and disconnect the ignition while you crank fresh oil into it. take out the spark plugs if you want to take it really easy on the bottom end.

Mclovin · April 3rd, 2006, 12:09 AM

Quote:

Originally Posted by jeepfreak81

i think the BRAND new starter has a bad solenoid

Good ol' napa

jeepfreak81 · April 3rd, 2006, 07:13 AM

Quote:

Originally Posted by Muddinguy

Good ol' napa

Actually I have had good luck with NAPA starters... the fuel pump from NAPA however... is another story... hence why i wouldnt be suprised if it was bad after 100 miles.

this starter is an Autozone unit that i have NOT had good luck with, however I bought it used and continue to use the lifetime warranty

me -->

<-- autozone

SS · April 3rd, 2006, 08:57 PM

Murrays

Carter fuel pumps and Bosch starters

Haggar · April 5th, 2006, 12:33 PM

Yeah, pull it off at look at it.

If you had a hard hard start/flooding situation, it can put a surprising amount of gas past the rings if they aren't sealing great.

I had that in my 304, wet ignition - > flooded engine - > washed cylinder walls - > gas in the crankcase - > wiped out my crank bears and valve seals.

I had a 4.0 liter with only 4:1 compression in the #1 cylinder, it did the same thing, filled the crankcase with gas..

jeepfreak81 · April 5th, 2006, 12:47 PM

So far i have changed the oil and not tried to start it, as I need to change the starter yet... i will crank it with no power to the dist. for a few seconds when i do try to start it to circulate the fresh oil.... is there any other recommendations. The lower end has around 100 miles on it... I REALLY dont want to tear it apart again.

nitrous nut · April 6th, 2006, 10:37 PM

i have the same prob im putting a elct. pump on it.
did you get the motor to hot? that can take out a pump

jeepfreak81 · April 7th, 2006, 09:33 AM

Have the pump off and it looks fine... Im just hoping water doesnt get in the crankcase with this rain

I knew I should have put a rag in the hole.

My uncle wants me to check the carb, says they can leak down when the need a rebuild, but I think that is fine as well. I think I just flooded it terribly.

cjshawn · April 22nd, 2006, 08:05 PM

What carb are you running? I had the same issue on another vehicle. Figured it was the pump. Ended up being the junk quadrajet carb. ( Wich was a napa rebuilt one installed a month or so before I bought the truck). When I pulled it off fuel was running out of the bottom where the welch plugs were leaking. It would drain the float bowls down in less than a minute.

Toivo · April 22nd, 2006, 08:20 PM

Ive heard of both the carbs and pumps problems. Prolly the carb, if the engine is that fresh. And as far as NAPA goes, I buy almost all my parts there. I refuse to support shitty Autozone and especially Advance Asshole Pukes.

jeepfreak81 · April 23rd, 2006, 08:26 AM

Pretty sure i just flooded it horribly over the winter, maybe the choke wasnt working right. I got a new redtop battery threw it in after the oil change... cranked it a minute to get the oil to the top, turned on the kill switch and fired first try...

It was running on 3.5 cylinders but it was running

I had 4 fouled plugs and another that was firing only about 70% of the time.

April 2nd, 2006, 03:38 PM	#4
clarkstoncracker lol Join Date: 11-03-05 Location: OC - MI Posts: 40,743 iTrader: (37)	sounds like a bad diaphram in your fuel pump. Anytime you have alot of unburned fuel in the cylinder, you will get some in your oil. was there anytime recently you were cranking the hell out of this thing, and it didn't start? That gas left in the cylinders will just go into the crank case. __________________

April 3rd, 2006, 08:57 PM	#9
SS Shenanigans! Join Date: 12-12-05 Location: Washington Twp Posts: 5,124 iTrader: (9)	Murrays Carter fuel pumps and Bosch starters __________________ -Jeremy

April 5th, 2006, 12:47 PM	#11
jeepfreak81 81 inches of fun Join Date: 11-10-05 Location: Owosso, Mi Posts: 11,506 iTrader: (20)	So far i have changed the oil and not tried to start it, as I need to change the starter yet... i will crank it with no power to the dist. for a few seconds when i do try to start it to circulate the fresh oil.... is there any other recommendations. The lower end has around 100 miles on it... I REALLY dont want to tear it apart again. __________________ The 1946 CJ2A "Project USS Hermitage AP54" The Freak YJ 1966 M416 1/4 ton Military Trailer

April 7th, 2006, 09:33 AM	#13
jeepfreak81 81 inches of fun Join Date: 11-10-05 Location: Owosso, Mi Posts: 11,506 iTrader: (20)	Have the pump off and it looks fine... Im just hoping water doesnt get in the crankcase with this rain I knew I should have put a rag in the hole. My uncle wants me to check the carb, says they can leak down when the need a rebuild, but I think that is fine as well. I think I just flooded it terribly. __________________ The 1946 CJ2A "Project USS Hermitage AP54" The Freak YJ 1966 M416 1/4 ton Military Trailer

April 22nd, 2006, 08:20 PM	#15
Toivo Feel lucky? Join Date: 02-24-06 Location: Waterford/Union Lake Posts: 5,055 iTrader: (13)	hm Ive heard of both the carbs and pumps problems. Prolly the carb, if the engine is that fresh. And as far as NAPA goes, I buy almost all my parts there. I refuse to support shitty Autozone and especially Advance Asshole Pukes.

April 2nd, 2006, 02:50 PM	#1
jeepfreak81 81 inches of fun Join Date: 11-10-05 Location: Owosso, Mi Posts: 11,506 iTrader: (20)	Fuel in the oil? Is it possible for a mechanical fuel pump to be bad and dump gas into the crankcase?? I pulled my dipstick and had an awful lotta gas in my oil.... __________________ The 1946 CJ2A "Project USS Hermitage AP54" The Freak YJ 1966 M416 1/4 ton Military Trailer

April 2nd, 2006, 03:26 PM	#2
vwBOY it's how i roll Join Date: 02-04-06 Location: howell, mi Posts: 1,937 iTrader: (5)	same thing happens with my buggy does your tank sit higher then your pump if so get a valve so when you arent using it turn the gas off after i did that no more gas in the oil

April 2nd, 2006, 03:33 PM	#3
Captain Ledd Ranger Addiction? Join Date: 11-06-05 Location: Davisburg Posts: 2,065 iTrader: (31)	In the technical term of "possible" yes. But I don't really think so. Was it used for really short trips and the engine not particularly warmed up alot? That will make oil reek of gas. I think if it's running rich it will get some gas in the oil. How much are we talking about though? Like the level on the dipstick was way higher than the full line because of gas added? or did it just stink like hell of gas?

April 5th, 2006, 12:33 PM	#10
Haggar Covered in mud... Join Date: 11-06-05 Location: Oxford, MI Posts: 16,702 iTrader: (48)	Yeah, pull it off at look at it. If you had a hard hard start/flooding situation, it can put a surprising amount of gas past the rings if they aren't sealing great. I had that in my 304, wet ignition - > flooded engine - > washed cylinder walls - > gas in the crankcase - > wiped out my crank bears and valve seals. I had a 4.0 liter with only 4:1 compression in the #1 cylinder, it did the same thing, filled the crankcase with gas..

April 6th, 2006, 10:37 PM	#12
nitrous nut Senior Member Join Date: 12-19-05 Location: west branch mi Posts: 277 iTrader: (0)	i have the same prob im putting a elct. pump on it. did you get the motor to hot? that can take out a pump

April 22nd, 2006, 08:05 PM	#14
cjshawn Newbie Join Date: 02-09-06 Location: warren Posts: 17 iTrader: (0)	What carb are you running? I had the same issue on another vehicle. Figured it was the pump. Ended up being the junk quadrajet carb. ( Wich was a napa rebuilt one installed a month or so before I bought the truck). When I pulled it off fuel was running out of the bottom where the welch plugs were leaking. It would drain the float bowls down in less than a minute.

April 23rd, 2006, 08:26 AM	#16
jeepfreak81 81 inches of fun Join Date: 11-10-05 Location: Owosso, Mi Posts: 11,506 iTrader: (20)	Pretty sure i just flooded it horribly over the winter, maybe the choke wasnt working right. I got a new redtop battery threw it in after the oil change... cranked it a minute to get the oil to the top, turned on the kill switch and fired first try... It was running on 3.5 cylinders but it was running I had 4 fouled plugs and another that was firing only about 70% of the time. __________________ The 1946 CJ2A "Project USS Hermitage AP54" The Freak YJ 1966 M416 1/4 ton Military Trailer