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Fuel in oil

D

dusher

Member
hello again im having problems

hello again im having problems with 1 of my motors i have a 25 foot skip jack with twin aq140a

i have rebuilt carbs
i have replaced fuel pump

but i am still getting alot of fuel in oil to the point it wasted the bearings in lower motor

what else can i check or replace to get it to run right???
any help would be appreciated

i also had the same problem with a different motor aq125b again please help
 
"Fuel pump diaphram ruptures a

"Fuel pump diaphram ruptures are not all that common.
You having this much fuel in your engine oil is rare, and top that with this occuring to you TWICE, is even more so.

Given that all is good with the Engine...... short of fuel pump diaphram rupture, carburetor float issues and running extremely RICH....... there is not much that could cause this, IMO.

Any other ideas out there????

."
 
so recardo could the new fuel

so recardo could the new fuel pumps be having to much pressure causing the float to set high and flood? i am reakky confused on this issue and need much help thanks don
 
"Don, I don't know for sur

"Don, I don't know for sure. It would be good to see what other comments or suggestions come in here.

I do know this:
I doubt that the oil "fuel contamination" from a carburetor is occurring while the engine is running.... at least not without other significant signs.
This may indicate that it is occurring once the engine is off, thus some fuel entering via the intake system, down past the piston rings while static, etc.
I'd also think, IMO, that this would require a significant amount of fuel and repeat cycles!

If the fuel pump diaphragm was leaking, you'd have tell tale signs elsewhere....., again, I'd think!

I assume that the compression is to within specs and that it is firing evenly on all cylinders!"
 
"did "rebuild the carbs&#3

"did "rebuild the carbs" replace the float, the needle, and the seat? Did you check the new components to make sure they didin't leak? I've seen plenty of rebuilds where the float wasn't even checked let alone the whole inlet system tested.

did the fuel pump get replaced with a new marine grade unit? I've seen automotive pumps installed before....high risk but not 'rare'

Spend a lot of time trolling/at idle with low RPM? If yes, have you looked down the throat of the carb while running? Agree with ricardo that you should see some other complimentary indicators - rich odor to exhaust, maybe a touch of black smoke in the exhaust, plugs rich fouling, etc..."
 
"Do you troll with just one mo

"Do you troll with just one motor??? If so switch to the other motor to check for problems when trolling with that motor...is it possible to switch carburetors or fuel pumps between the two motors to further isolate the problem. The solutions listed by Ricardo and Makomark are the most probable but here are some less likely but possible things to consider ...is it running on all cylinders...a "dead" cylinder will pump a lot of unburned gas into the combustion chamber and past the rings. The other possibilities are an engine running at too low a temperature due to a bad thermostat, a choke not opening fully or a defective crankcase ventilating system."
 
"alrighty then here is my prob

"alrighty then here is my problem i found out that it is running on 2 cylinders

the engine has spark on all 4 cylinders, and gas to all cylinders

what could cause it to run on 2 cylinders

compression readings are 130-150-145-135

need to find problem before i sell this damn thing!!! any help again would be appeciated

dom"
 
"[b]**has spark on all

"**has spark on all 4 cylinders
**gas to all cylinders
**compression readings are 130-150-145-135

Compression, fuel/air and an ignition source usually completes combustion!
Confirm with us how you know it is running on only two cylinders!

."
 
"Crossed spark plug wires(

"Crossed spark plug wires(Most likely of all mentioned causes), distributor cap internally cracked, damaged rotor??? If it is running on only two cylinders, it would just about run at all and would barely idle if at all. A very unlikely possibility is that each of the "dead" cylinders has a valve which isn't opening for some reason...although that is possible, it would be a real longshot and could be checked by simply removing the valve cover. Let us know what you find!"
 
when i pukked the wires off of

when i pukked the wires off of cyl 1 and 2 no change in motor at all

pulled plugs very strong gas smell but no ingnition
 
"Don, when at idle only, or no

"Don, when at idle only, or not under load, you may not find a huge difference. The engine may need to be under load for this to show up!
You will need to perform a P of E... (Process of Elimination)
Check and/or replace one item ONLY at a time until you find what the problem is.
Start with the appropriate firing order.
See what color your spark is under very low lighting.
If points, set with Dwell meter only. (gap is an estimate only of dwell)

Sorry, there is likely no short cut on this when trying to help someone via the Internet!

."
 
"Well, there are things that I

"Well, there are things that I may not be able to suggest simply by way of not being right there/hands on!
It's hard to say..... One of us may notice something more unlikely related, but may just be part of the cause, for example, if we were right there to looky/touchy!

If it were me, and if your compression test is accurate, I'd most likely start by taking a closer look at ignition spark output and firing order and condition of these ignition parts!
ALL OF THEM!
I'd want to look at spark plugs, but only after the Ignition System becomes known as A OK!
And, of course, after a short sea trial can be done!

I'd also re-examine the fuel delivery system.... pump/carburetor.
I'd most likely start with fresh engine oil/filter!

After thinking that I may have found an issue, I'd operate the boat in the water!
This would be the time to examine spark plugs as mentioned!
This would also be the time to sniff test the oil! (although I do not know how quickly this has been showing up!)

Again, this is from the disadvantage of being at my Keyboard!
Hopefully more suggestions will come in here.

Eduardo (El P.) is certainly more familiar with the little OHC 4's than I am, but since some of this crosses over, I am posting.

I believe that a thorough P of E will get you closer and there much faster.
Hang in there!
And if you should resolve this, please post back with your findings!
It's always good to follow up so others may share in this!

."
 
ok i gave up and took it to a

ok i gave up and took it to a mechanic paid 400.00 for him to tell me it has to be in the carbs


so i want to change them with a conversion kit single carb

can you tell me what would be the best to go with my aq140a and where i can purchase them

i have twin motors can i get away with 1 side only or should i do both

i heard weber makes a conversion kit but not sure if it would be best for my application

mechanic also found noise coming from out drive

i really want to get this boat running right please help!!!!!!!!!
 
"Don, if you want to go to sin

"Don, if you want to go to single carb, check this. Several forum members have reported very good results with the Webers.

http://www.redlineweber.com/html/kits/k861.htm

You mentioned that the engine was running on two cylinders, and by your post I am assuming they are #1 and #2. So, if you have very wet spark plugs in cylinders 1& 2 but you have spark, you probably have an overflowing carb or a carb with the wrong idle mixture settings. That should not be very difficult to fix, as it would probably involve just adjusting the float height and/or replacing the needle valve and seat assembly.

I would also check that both carbs are properly syncrhonized and that the distributor rotor and cap, ignition wires and spark plugs are in good condition.

Good luck."
 
ok i guess its time to put thi

ok i guess its time to put this post to bed.

i have finally found my problems!!!

turns out the reason for the motor running on 2 cyl was a clogged passage to the idle jet had the carb shop fix it ran ok for a little while then same problem again got fed up with carb shop took it apart again myself and found the idle jet was completly clogged boat now running good enough i got to take her out for a 60 mile run. now just fix my gimball bearing and ill be back on my way

thank you all for all the help you provided me it was very helpfull im sure ill be back to ask some more questions


thanks again don
 
"Don,

Um..since you said yo

"Don,

Um..since you said you had twin aq140's im assuming its a 1975-1979 if all parts are same as production...I am assuming that you have probably a 270 or 280 series aquamatic drive????Just to let you know those drives DO NOT have a gimbal bearing or gimbal housing!! Nor do they need engine alignment and so on and so forth .. Again Im assuming these things but I am glad your boat is up and running!!"
 
"Don, Jesse is correct! Your t

"Don, Jesse is correct! Your two systems use what's called a "Primary Drive Shaft".... <u>no Gimbal system what-so-ever, and thank goodness!</u>
You will have a single PDS bearing on each engine's PDS.
I would definitely replace these if no recent history of them being replaced! I can tell you first hand about the damage that a failure here can and will cause! NOT GOOD!
This is an over-the-counter bearing (#6206), and the seals (35x62x7mm) can be easily brought in by most any bearing supplier!

Any of these AQ series engines DO require an alignment, but only during initial engine installation!

."
 
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