5HP Briggs and Stratton

[Trotter]

Re: 5HP Briggs and Stratton

Thanks for the help the explanation made it simple to understand.

But wouldn't you know I test run this motor three times on Friday and fired up three times first pull like a champ. Then I finally take it out to the lake annnnnd.... it wouldn't start.

I was pulling on that cord like a mad man for a couple of hours and it just would not start. Needless to say I was very disappointed considering I was able to start it three times in a garbage can a couple of days prior.

I guess I'll try starting it again in a garbage can but I kinda don't see the point as it wouldn't start in the lake water. I figure something's broke and for some reason it wasn't broke 2 days ago. Or maybe it was and I just didn't know it. The only thing that's changed as far as I can tell is I flushed the oil out of the lower unit and pumped new gear oil in.

It definitely was getting fuel because I popped the cowl and saw fuel was making it into the filter. Though a couple of times it looked like fuel was leaking from the primer but most likely because I flooded the motor and was trying to push more fuel into it thinking that it wasn't getting fuel.

Anyhow, it's been a very disappointing weekend as I was really looking forward to boating. I think I'll just return this motor and sell my Briggs and by something brand new.

 

[Wishiniwuzfishin]

Re: 5HP Briggs and Stratton

I was following your post when you first posted because I own a Briggs too. I lost track of your post for awhile then just found it again tonight. You sound really discouraged and I can't blame you but I think you need to pause for a minute. Were you serious about pulling your starter rope for "a couple of hours"? If you are I see why you're frustrated. But If it didn't start within a couple of minutes....maybe waiting a few minutes...then trying to pull again a couple of minutes, it probably has a problem and won't start untill the problem is solved. Don't kill yourself pulling it for a couple of hours. If it started easily in your test tank 3 times then you take it to the lake without doing anything to it, it is very unlikely something broke in between. You said something about buying an adapter for the Merc motor gas line. Does that mean you were using the Briggs gas can? If so, did you remember to add oil to the gas? Briggs fuel would be straight gas....2 stroke Merc needs oil mixed. If you ran the Merc on straight gas it would definetely have hurt it but I have no idea how long it would take to "kill it". I'll wait for your answer then we can go from there.

 

[Trotter]

Re: 5HP Briggs and Stratton

Well what I meant by pulling for 2 hours is I was trying for 2 hours pausing as much as 20 minutes in between tries.

Yeah, I had to purchase a Merc fuel kit because the nozzle on the end of the hose that came with the Briggs doesn't fit the fuel fitting on the Merc outboard. The Merc nozzle fits and appears to work. I say appears to work because I can see the filter under the cowl fill up when I pressurize with the pump with no leaks. Also I'm sure it works because it did start and run continuously before just 2 days prior.

I did a 50:1 mix with the fuel. I didn't use straight gas and it ran fine when I tested it in the tank. The exact same fuel (since I filled up the 3-gallon tank) was used when I took it to the lake.

When I test fired it in the tank it fired up on the very first pull and ran strong. I stopped the motor waited a few minutes and started it again with no problems. Then I stopped it again, walked away for a while, and came back and it started right up.

2 days later I take it to the lake and it refuses to start. Paranoid I even ran back to my car to go over the starting instructions just to make sure I wasn't screwing something up.

The only thing I've done to it since after starting it the first time was changing the lower unit oil.

I will say one thing though. When I first bought it and popped the cowl I noticed that there was still fuel in the white cylinder I assume is part of the fuel filter or water separator. I popped the cowl at the lake just to see and saw that there was nothing in it. I would pump the line again and it would fill back up but still didn't start. That's the only thing I noticed but didn't take it as being out of the ordinary since it seemed to fill back up after squeezing the pump a few times.

 

[Wishiniwuzfishin]

Re: 5HP Briggs and Stratton

First let me tell you I know nothing about your particular Merc motor so take my suggestions for what you feel they are worth. But I have had Johnson and Evinrude O/B's for over 40 years and own 5 O/B's now, one of them the Briggs. It would seem to me your most likely problem is a fuel problem. Your ignition system (spark) is unlikely to go bad in between the time you tested it and then taking to lake. Same with compression. That leaves fuel. In my experience I think it is hard to flood a 2 stroke engine that has good spark and compression, unless it has a defective or badly adjusted carb, which yours apparently does not since it started so easy 3 times. If it has spark and compression and it gets gas it fires. They're not like the old car engines where you can just keep pumping the gas pedal and flood it. That leaves lack of fuel as where I would look first. First thing I would do is pull the plugs tomorrow and see if they are "wet". I'm betting they aren't and if not I would squirt some gas/oil mix right in the plug holes before replacing the plugs then try and start again. I have a plastic spray bottle I use to spray gas/oil in mine and I also have a large plastic syringe type thing I got at Walmrt I use to squirt the mix in. That should get it to at least pop a few times even if it isn't getting gas. If the plugs are wet.....then the problem just might be spark.

 

[Wishiniwuzfishin]

Re: 5HP Briggs and Stratton

1 more thing....although I've never seen one on any of my Johnsons or Evinrudes.....your merc doesn't have a fuel shut-off valve somewhere under the cowl like the Briggs has does it?

 

[Trotter]

Re: 5HP Briggs and Stratton

Funny enough I was thinking about checking the plug when I get the chance. When I had time to think about it on the lake (and I had a lot of time to think about it) I was thinking that maybe the plug wasn't firing.

Everything you said makes sense now that I hear it from someone else. I was a small engine mechanic in the Navy but for some reason I just feel lost when it comes to this outboard and some of the obvious things to do I'm overlooking. I never worked on 2-strokes before so maybe there's a mixture of fear that I'm going to seriously screw something up because I don't know how different they are from 4-strokes. I think I'm just afraid to tinker too much with it since I do have the option of taking it back.

Tomorrow's Memorial Day so I don't think I'll get a whole lot done tomorrow. I would have to buy a few things like a spray bottle and such. I'll try checking out the plug and see where it goes from there. Will update later. Thanks!

 

[ondarvr]

Re: 5HP Briggs and Stratton

There should be a small on/off switch on the front left of the motor when you're looking at it from the front. This switch even gets me sometimes, I never use it to stop the motor, but it does get bumped and switched off and I don't remember to check it.

 

[Trotter]

Re: 5HP Briggs and Stratton

I wish it were something that simple. I checked to make sure the switch was on every crank.

 

[Trotter]

Re: 5HP Briggs and Stratton

I stuck it in the tank today and verified the plugs are firing but couldn't get it to start. One plug was strong while the other was sparking but a hair on the weak side compared to the first plug but it was firing nonetheless. I tried squirting a fine mist of fuel into each cylinder and it didn't start. Then I squirted quite a bit into each and it didn't start. Used some carb cleaner and sprayed a little more fuel in and nothing.

I checked the primer and it's working. I pulled it a bunch of times until fuel started leaking out of the carb. Now I will say that it does not appear that fuel is making its way to the cylinders because each time I try pushing gas through the plugs look dry. The only time they were noticeably wet was after I sprayed fuel into the cylinders directly.

 

[ondarvr]

Re: 5HP Briggs and Stratton

Could be flooded at this point, I don't think there's anything really wrong with it, it probably has more to do with you not being familiar with how it likes to awakened in the morning.

With the plugs out pull it through a dozen times or so to clear it out, wouldn't hurt to put new ones in while your at it.

don't pull the primer out this time and turn the knob all the way to the right (c/w). If it starts great, if not then pull the knob out and try a few more times.

 

[Wishiniwuzfishin]

Re: 5HP Briggs and Stratton

Its hard to say how much fuel/oil mix I have squirted in my plug holes before but I think I may have squirted more than you have. I have had the bottle on a stream setting and squeezed the trigger like 4 or 5 times in each cylinder after it started spraying good. It even starts running out of the cylinder sometimes. I try to get the plugs back in as quick as I can. It does sound like you might have got enough fuel in there for it to at least fire if it was going to but it wouldn't really hurt to try it again really giving it a good squirting. You can always clean the cylinders out like ondarvr said by cranking it with the plugs out and drying the plugs. I still think lack of gas is your problem especially when you said about the plugs being dry and you weren't sure fuel is reaching the cylinders. But like I said I have no knowledge of the primer etc operation of your motor. Also maybe you should move this to the Merc forum. I think a lot of people see the Briggs title and don't even read it.

 

[Wishiniwuzfishin]

Re: 5HP Briggs and Stratton

Maybe you can try tapping lightly on the carb also. If the float is sticking that may help.

 

[Trotter]

Re: 5HP Briggs and Stratton

Ondarvr, you are the man!

I pulled the plugs out and pulled the cord about 10 times and could see all this junk coming out of the cylinders. I put the plugs back in and tried to start without priming and it sputtered! That was more than I was able to get on my own. After three attempts and three sputters I pulled the plugs back out and blew them out again cause I could tell it was actually trying to start. Put the plugs back in and it fired right up.

But now here's the dilemma, I'm wondering if I'll have to do this every time. I mean it started fine the first day I tried it, but would letting it sit after it's been fired up cause this every time?

I wanna thank everyone that helped as I learned quite a bit so I'm very thankful. And also I agree if a moderator could move this to the Merc forum please.

I'm letting it sit now for about 30 minutes to see if it'll start right up.

Edit: It idles a bit rough at both low and high idle. I ordered new plugs and will put them in tomorrow.

 

[ondarvr]

Re: 5HP Briggs and Stratton

Great news, good job.

I would change the plugs and then run some Sea Foam through it, you can get it at most auto parts stores, use the de-carb method described in FAQ section. Basically its just dump a hole bunch in a small amount of gas and run it for a few minutes.

Once you get it up and running at full operating temperature for a little bit it should start and run fine.

 

[Tom @ Buzzard Bluff]

Re: 5HP Briggs and Stratton

<But now here's the dilemma, I'm wondering if I'll have to do this every time. I mean it started fine the first day I tried it, but would letting it sit after it's been fired up cause this every time?>

It certainly shouldn't! If so you have a severe fuel delivery problem that must be resolved.
Try this----next time see it it will start without being choked. If it will then it is very likely that it is getting too much fuel. Could be any number of reasons but I'm betting on a float valve that isn't shutting off fuel delivery when the float bowl is full. I've had that happen on a B&S lawnmower and it filled the engine with fuel. If it won't start without using the choke pull the plugs and see if they're wet or dry. If wet then the float/needle/seat is at fault. If dry try it again with choke---just a couple of pulls with choke on then turn it off and try a couple of more pulls. If still no glee then try the choke again for 3 pulls and then without if it fails to start. If nothing then look at the plugs again. By 'walking up on it' in this manner you can at least determine if the fuel problem is too much or too little.

I'm disturbed by your words <One plug was strong while the other was sparking but a hair on the weak side compared to the first plug but it was firing nonetheless.>.
That tells us right up front that either there's something amiss in the ignition system or that your test method is inconsistent. You need an ignition tester that checks spark by an adjustable gap as well as under compression. Horror Freight has one for only a few $. They also have inline testers that fit between the spark plug and the spark plug boot. By using a couple of these you can tell if the ignition system is 'skipping a few beats' when running.

Trouble-shooting is a process of putting one foot in front of the other in a logical sequence. A bit of logic and shade-tree testing goes a long way too!

 

[Trotter]

Re: 5HP Briggs and Stratton

I let it sit overnight and was able to start it again. Except this time instead of priming it as the instruction manual suggests I tried a couple of pulls first. It didn't start so I only pulled the primer once instead of three times (as said in the instructions) and it fired right up.

So I'm thinking that when I took the outboard to the lake it was simply getting flooded by priming it. Just a guess but it seems to make sense now.

After I get the new plugs today I'll replace them but it sure does smoke quite a bit (white grayish smoke). Could heavy smoking be an indicator of a potential problem overall? I was always told that 2 strokes are a bit heavier on the pollutants so I'm not sure. White gray is making me think that it's running rich.

 

[ondarvr]

Re: 5HP Briggs and Stratton

Whitish gray smoke is normally steam created from the cooling water, not an issue. There isn't much that goes wrong with these motors.

You need to run the Sea Foam and get this motor running and up to operating temperature so you can see how it actually runs.

 

[Tom @ Buzzard Bluff]

Re: 5HP Briggs and Stratton

<I let it sit overnight and was able to start it again. Except this time instead of priming it as the instruction manual suggests I tried a couple of pulls first. It didn't start so I only pulled the primer once instead of three times (as said in the instructions) and it fired right up.>

Excellent! That's the process I termed 'walking up on it".

<So I'm thinking that when I took the outboard to the lake it was simply getting flooded by priming it. Just a guess but it seems to make sense now.>

Quite obviously true.

<After I get the new plugs today I'll replace them but it sure does smoke quite a bit (white grayish smoke). Could heavy smoking be an indicator of a potential problem overall? I was always told that 2 strokes are a bit heavier on the pollutants so I'm not sure. White gray is making me think that it's running rich.>

'ondarvr' may be right about it being steam but if so that is an even bigger concern. An outboard that is cooling well shouldn't be steaming! Check the tell-tale for good flow from the water-pump!
But I'm betting that it's residual fuel/oil mix in the exhaust housing leftover from all the previous flooding that is 'cooking off' inside the housing. As you note it may also be running far too rich. Before you do anything else it's time to 'read' the plugs. Pull them out and look at them under good light. Are they very black and wet appearing? If so then it IS running too rich. Verify it by putting in the fresh plugs and running it long enough to get a reading on the fresh plugs. If they too are getting black and look wet then you'll KNOW that it is running waaaaay too rich.
Google 'reading spark plugs' and read up on it. It is an extremely useful tool for analyzing engine problems. Old time racing engineers could learn an amazing amount of information from just reading the plugs. Spark plug manufacturers used to send reps to help the engineers and mechanics for the entire month of May in the ramp up to the Indy 500. May still do so.
In the simplest of terms wet, black electrodes and porcelain indicates a too rich condition. White, almost dusty dry electrodes and porcelain is a sure sign of too lean and an early predictor of impending failure. If they are accompanied by tiny droplets of once molten aluminum on the electrodes failure mode is already underway and inspection of the piston crown will reveal where the molten aluminum is originating. Ideal reading is dry, dark tan to light brown electrodes and porcelain.
Before you run it again buy, beg or borrow one of the digital thermometers that reads temps merely by pointing it at the surface you need to read. Use it to make sure that the motor isn't cooking itself while you're running in the new plugs! Local auto parts stores may have 'loaners' that you can rent quite reasonably.
Keep "walking up on it", eliminating one factor at a time. Trying multiple solutions at once is very counterproductive!

 

[ondarvr]

Re: 5HP Briggs and Stratton

These small Mercs don't use thermostats (they have a place for one, but its not in there), at least the earlier models of the same design, so unless you get them running hard they don't get up to temperature, which makes reading a plug difficult.

My Merc (same design) will put out whitish smoke right after it starts and depending on ambient temp, humidity, and other things, may put out a whitish steam at other times too.

These Mercs also tend to collect more un-burnt gunk in the exhaust area than some other motors, so unless they get run hard it collects in there and oozes out later, or can cause discolored smoke. It can also plug the exhaust and cause poor running if it never gets up to operating temperature.

Don't worry about this stuff right now though, run the Sea Foam and report back.

 

[Trotter]

Re: 5HP Briggs and Stratton

I'll run the seafoam today when I get home from work. But to respond to Tom the original plugs are black. I saw that and figured something wasn't right and that they had probably been run that way for a long while by the previous owner.

The smoke is definitely the exhaust and not the cooling water. The wind kept blowing it into my face causing me to gag a few times. I would like to look into a few other things as well while I'm at it.

After considering it for a while I think way too much fuel is being burned which might also be the reason why it runs a tad rough at idle. I looked at the tank this morning and saw that almost a gallon was gone after only having run the motor at mostly idle speed for a combined 35 minutes after getting it started. So is there anything else I can look at to determine the cause of that after I run the seafoam through?