Briggs 18HP problem!

H

HighSteam

New member
Im having problems with my 18hp vanguard (356447-0079-G1).
It is leaking oil from the breather tube to the carb and air filter, which is causing some bad "misfire/backfire".
Its an almost new motor like 150hrs, so i expect not to be the rings.
I already changed the spark plugs, which didnt help but they looked with lot of carbon built.
Ran the motor with some seafoam in the fuel yesterday to clean it a little bit, hoping it would help.
Maybe was a valve being stucked or some like that.
the motor is runnig a little low in rpms and intermittent. goes up and down like 60 to 100 rpms and is like 100 lower than used to be.
Im planning on cleaning the "breather", the one that connect to the breather tube under the air filter.

Anyone had this problem before? Any tips on where to look.
 
Will try it too. i have too the actual one has the front full of oil from the spitting.
 
Yeah that was my first option. But oil level is good. like 3/4 full.
 
Check the gasket on the oil fill cap and the grommet on the dipstick. Sometimes if the crankcase is not air tight except for the breather, it can cause oil to spew from the breather. The breather could also be dirty or bad.
 
The main reason for the backfire is when you need to shut down the engine, lower the rpms and let it run for a min then shut it off. Our sirocco unit done this until we started lowering the rpms then shutting it off.

Do you have problems trying to start yours? On our new pressure washer it has a 21hp Briggs and it takes for ever for it to start? Any problem solving for that? It's like it's not getting the fuel
 
I actually like the backfire though when you shut off the engine. It's the 'job complete' signal for me. My Vanguard never backfired but the Kohler I have on now does.
 
Ok so i changed the breather, but the problems dont go away!.

Now is not spitting out of the breather but the carburator is doing a really bad "pop" sound.
Im not sure if it is flooding in gas but the sound is pretty bad. The air filter is sprayed with gas as well.
The motor runs unpowered, like about to die when under load. And the smell of fuel in the area is bad too.
I thought it was the carb that was bad, changed it with the one of my parts motor and still doing the same.
I noticed that the fuel filter, before the diaphragm/pump used to be about half when all throttle up, now is full.
I also changed the spark plugs a couple days ago and went to check them and they are all black again.
And it is spitting a little oil out of the exhaust too. not that much but shouldnt do it.
I checked the oil level and still the same where i filled it (3/4 full) so the fuel is not mixing with the oil.
Any ideas?
I will do a compression test tomorrow to see if the rings are causing problems, but im not sure they would have something to do with the fuel.
 
Take it back to where you got it tell them to replace it it should be under warranty.I hate when new stuff breaks.This stuff we buy is high enough and to have problems like you have has got to be aggravating.Where did you get it?
 
Yeah that would be the best. But i got it from a friend, it was new but he didnt have no papers or any info for warranty or such. So never contacted briggs about it.
Well, after checking the valves i found a broken pushrod which was the trouble maker. I was able to change it and test it run. Its running ok for now. Going to do a oil change and air filter change too tomorrow and test it again. Might be checking for valve clearance just to be sure.
 
Here is another reminder, that "sticky valve syndrome", that never was an issue before, is most frequently caused by bad gas..
I'll bet Kiloman's broken valve came after a few weeks of infrequent running, whilst the system sat it a "hot" location ??

Another "sticky valve gone broken" can be caused by running an engine on slightly-diluted oil,
from a bleeding carb allowing fuel to drip into the motor, causing seepage into the oil,
and breaking down the lubricity of the oil.
Check your oil EVERY day, smell it, to make SURE it does NOT smell like gas,
and use fuel stabilizer in the fuel, if it is going to sit in the tank for more than a couple weeks.

And for those of you with over 6,000ft elevations.. add "altitude issues"..
Not "easily" getting enough air causes more "eccentricities" in the engine system..
if your air filter is even a little bit busy, the spark plug fouls, and flooding syndrome takes charge.
A plugged air filter can cause the fuel to flood the engine, as it sucks its brains out trying to get air through said air filter.
Which reminds me..
Anytime you guys have an engine issue, of any kind.. take the air filter off for the duration of testing.
Then, when you are putting the filter back on, after troubleshooting is complete,
make sure the engine acts exactly perfectly the same, with or without the air filter..
I can't tell you how many times I have found someone fumbling through spark and fuel problems with a
partially plugged air filter confusing the symptoms. Just eliminate it from question.

I hope we see y'all in San Diego again in October :{)
my pressure washer troubleshooting and bulletproofing class could help fine-tune your troubleshooting skills.
 
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Thanks for the replies everybody. for sure will keep an eye on the daily maintenance to avoid this problems.
 
Whenever I get an opportunity, I like to turn one man's troubleshooting venture into a general training session..
SO few of you guys know everything you'd like to (or should) know,
and with my experience, I'm willing to share..
These blog posts I insert are exerpts from the training I've given to contract cleaners for almost 30 years.
Sorry I got names mixed this time, but hopefully people that read this thread will gain a nugget of insight
which can help them through the perils of running high performance cleaning equipment.
I happen to have an unusual combination of experience.
call me if you want to talk about what goes wrong with Kohlers, or whatever.
Even better, come to one of my educational events, as you can.
 
Jerry you bring a weath of knowledge to this board always read your post for the best advice.How do you thing a digital 12volt themostate with a themocouple will hold up verse the cheap dial kind?
 
I have built several heaters for the diving industry for heating multiple umbilical-wetsuits in frigid waters..
That system utilizes digital temp control.. that works real nice for accuracy, but..
Larger more consistent flow is the key there, if you are working with lower flow, allowing higher temps,
..the off-on dwell time can allow big mood swings in temperatures, but..
the digital controls are MUCH more accurate than the mechanical switches.
..Just get ready to spend another 300% too.
Also, since you have to protect the probe from our kind of pressures..
be SURE to use heat-transfer compound inbetween it and the thermo-probe vessel.
 
The whole shooting match is around 100 bucks much better than $25 all the time An added bounes i can turn my burner switch on and tell the inside temp in the box truck.Great for this winter if we have one.
 
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