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Fuel in Crankcase

keevo52

New member
"HI guys
This is my first pos


"HI guys
This is my first post, location Newcastle NSW Australia, from what I have seen this is a very informative site.
I have recently discovered fuel in the crankcase of my Honda BF30D4, I have seen other posts on this site where the general comment is that the fuel pump may be faulty, I have a mechanic coming to check the motor tomorrow, he will do a compression test, change the oil and plugs, I will tell him about the possible fuel pump problem, my question is would the fuel/oil mix damage the engine in any other way eg lack of proper lubrication? The outboard has a limiter system on it which if any faults develop in the oil or cooling system the engine gradually goes slower, I have only noticed this on the last two occasions that I was on the water total running time 2 hrs tops, the engine would have been lucky to have done 40 hrs since new, any guidance appreciated.

Keevo52"
 
"Hi Christopher,
When first I


"Hi Christopher,
When first I read your post, I had a reaction and made a noise much like a teenage girl would make if it were suggested to her that she give an old man like me a passionate kiss... eeeooooyuuuuuuuuuu! Or something like that.

If your engine was depowering due to low oil pressure caused by fuel dilution, I would be a bit concerned about main and rod bearing damage. The concern would be logarithmacally associated with how many miles I travel offshore. If you do near shore operations and own a good VHF radio and ground tackle, then that's one thing. If you travel 20 miles to that favorite fishing ground, that's something else entirely.

Yours is a case of the value of a good oil analysis lab. If you take an oil sample and it comes back with high copper and lead content (bearing material)and or chromium (rings) then you might want to stay closer to home. If not, then drive on.

One thing that could screw up these findings is if this is the break in oil as a new engine WILL exhibit higher levels of metals as the engine wears in.

If you don't have access to oil analysis, then find out how the gasoline is getting in the crankcase and stay closer to home at least for a couple of trips. If, in fact, the fuel pump (usual suspect) is faulty, this should be a warranty issue and you need to be careful if using an independent mechanic to do any diagnosis so as not to void your warranty.

I will say, though, that when and if you ever notice your engine power down again, that you investigate the reason immediately and not take another trip as you say that you have in this case.
Good luck Mate!"
 
I'm sure you mechanic will

I'm sure you mechanic will also check t-stats and that the engine is coming up to normal operating temps. If not another cause for fuel in oil. Symptom would be the engine takes a long time to run without choke assist.
 
"I'm certainly not an expe

"I'm certainly not an expert -- however my Honda 20 was doing the same thing. When I called my local Honda mechanic he told me that sight-unseen he was 100% sure that my engine was running cold and that would be caused by a bad thermostat. Sure enough, when I brought the engine in he pulled the thermostat and yes, it was stuck open. Thermostat was replaced and all was fine."
 
"If your engine slowed due to

"If your engine slowed due to the oil, the oil light should have gone out.

A couple other things for him to check.

After the oil change...

Perform a cylinder drop test to be sure all cylinders are firing correctly. If One of the carbs has a problem, it could be diluting the oil with gas.

I am also sure, he will check the condition of the spark plugs after or before he does this.

If the fuel pump is the issue...it would be easy enough to find just by unbolting it from the engine and squeezing the fuel pump until it gets hard...if the pump leaks where it goes into the head...you have found the issue.

Good Luck!"
 
"Hi Guys

Well I had the mec


"Hi Guys

Well I had the mechanic come and check the engine out, he agreed that there was excessive oil in the crankcase but was mistified as to how it got there, ( it could of been over filled last service)he said it was unlikley that the fuel pump could be faulty as the motor would have been running rough, the oil he used at the last service was a synthetic oil of excellant quality, he said that this oil does thin out and become dirty with use,he replaced the oil and filter and carfully refilled the engine to the correct level, he did a compression test and found all to be normal, he said to give the motor a run and check that the oil pressure monitor light comes on and stays on,I was to check the oil level after each use and to give it a run at speed to check that the performance is what it should be, this I did and all appears to be ok, As I was using an ethanol fuel in the motor since new I will give a higher octane fuel a go as there has been reports of ethanol causing problems with outboards here in Australia, Although Honda say its ok to use ethanol, the use of it may be behind the problem that I had. (my idea to change the fuel not the mechanics)

I would like to thank all who replied to my post I have printed out the replies and will keep them for further reference.

Tight lines

Keevo 52"
 
"I do not know how many hours

"I do not know how many hours are on your motor, but unless it has 400 - 500 hours on it, the rings have not completely seated and you should not use synthetic motor oil. If you do, the rings will never seat properly.

This may or may not be a cause of your problem.

Honda recommends that you use 5w-30 API
service category SG, SH or SJ oil.
The SAE oil viscosity and service
category are in the API label on the
oil container.

After 400 - 500 hours synthetic is ok, but you still need to change it per the maintenance recommendations.

Why waste the money?

Sythetic for the lower unit is ok any time."
 
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