Welcome to the DoItYourself Forums!

To post questions, help other DIYers and reduce advertising (like the one on your left), join our DIY community. It's free!

Briggs and Stratton 5 HP wont start


Charliegates's Avatar
Member

Join Date: Jun 2014
Posts: 44
FL

06-19-14, 07:22 PM   #1  
Briggs and Stratton 5 HP wont start

Model: 130202 (Mine uses the magnetron over points)
Briggs and Stratton

My dad went to a yard sale and bought a Kee mower deck. I guess they were really nice back in the day or whatever. The guy threw the Briggs 5HP on it for free. But, it did not start, even with fuel in the tank. So, me being in BMW STEP, graduated now, considered this to be an easy tackle, small engine, no start, must be the carb. So I sprayed ESF into the carb, and it did not start. I thought "hmm the carb must be blocked allowing nothing to go out". So I tilted the engine upwards to help the fluid flow into the intake, and I finally was able to get it to turn over. So, I decided to rebuild the carb. I did so, and still nothing flowed. Then, I rebuilt it again, and nothing. So, I turned to spraying fluid into the intake, only then was I able to make it turn over. So, I bought a new carb and fuel tank. While waiting on the carb to ship, I took off the head and inspected the upper cylinder, nothing out of the ordinary, some carbon on the valves, some on the head, not very much on the piston head. Also, there were not really any scratches on the inside of the piston, so i assumed it had good compression. Then, still while waiting, I thought that using the drill to start it over the pull start-recoil, would be better, since it would make less wear and tear on my recoil assembly. So, I would spray fluid into the intake, turn the drill, and it would make some revolutions before it all evaporated. Finally the new carb and tank arrived, put gas in it, hooked it up to the intake on the engine and viola! It ran . But, I was going to reassemble everything, and I did, and I thought that I could start it and fiddle with the fuel/air knob to get it to run nicely. Well, the pull start was unable to start the engine. No amount of me pulling was able to get it to run under its own power. So, I took it off, and hooked the drill up to it (15/16 socket, extension, and drill, usually, the drill would do about the same number of revolutions before it wanted to recoil) and it started. I also had the choke pulled out if that makes a a difference. Well, as I was trying to adjust the fuel/air knob, the extension orbited out of the correct orientation and caused the shaft to break (including the clutch) just under the flywheel. I put it all back together and ordered the parts.

Fast forward to this past week. It installed new piston rings, then put the crank shaft in, aligned the cam with the crank shaft, after installing the connecting rod and splasher. Then installed a new gear case gasket. Then, installed the head. I turned the PTO end of the shaft a few times to make sure I could hear compression, and see the valves move. I also put while lithium grease on the part where the flywheel goes, and for the connecting rod space as well. Also put some on the PTO end. I also filled it up with oil. Then came the first test, no luck. This was with the carb removed. I pulled about fifty times, and it only got close to making power under its own. I was also spraying ESF because without it, I would not know if there was a spark. So, no luck for a while. Yesterday, I was able to get it to pop after pulling it once or twice (out of what seemed to be about a hundred tries, literally). All of the pulls, I used ESF. Now, I hooked the carb up and put gas in, and still no luck pulling it. Not even on choke, adjusting the knob, putting ESF into the head OR the carb, nothing, though it seemed to be getting very close. Then I figured out how to hook the drill up, and tried it that way. I seen a flame out of the exhaust hole and thought nothing of it. A few tries later, and the outside of the carb caught on fire (loose gas mostly) then I sprayed it down carefully, and let it sit. I did what you guys suggested last night and the key was and is intact. I took off the head this morning to inspect the valves, and they looked liked they were fine (I can provide photos for your inspection) but there seemed to be gooey carbon on the head of the piston and cylinder head (I scraped it and removed it). I replaced the spark plug as well. I know the flywheel is providing spark and the coil because I held onto it as someone else pulled and it gave me a good little tingle. I tried to start it with the carb removed and it caught on fire again. I looked in the breather hole and the springs for the valves, im not sure how to recognize them on this engine (if its right or wrong, again, I will provide photos for your inspection). I try it with the carb off because that is how i confirm igniton, if it runs for a few seconds, then we are good. But, no such luck. I hope this helps. The valves also moved when i turned them with my thumb. Also, today, I was using the pull start, no more drill after the engine caught on fire.

People have said it is the ignition coil. I have taken several videos recording the spark that it gives, both during the day, and during the night. I could post them if that would help.

I have many reasons to believe that it has good compression.

1) It is difficult to move without the pull start attached (by hand).
2) I can hear it.
3) Put my finger in the plug hole and it blew past.
4) Installed new rings.
5) Installed new crank case gasket.
6) When I take the head off after trying to start it, I CAN SEE GAS ON THE VALVES AND INSIDE THE HEAD!!!!!!!!!!
7) Valves open and shut according to piston position and there is no overlap between the intake and exhaust opening and closing.

The sixth point leads me to believe it has sufficient compression. Because, gas from the tank would not be in the dry head, if it did not have enough compression to suck them in. (I know it was dry because I installed the tank when the head was 100% dry). I have poured gas, ESF, and carb cleaner right in the head, and NOTHING!!! I think the spark is so weak that it is unable to ignite the combustible fluids. But it gives me a good little jolt when I pull the starter, which leads me to believe that it is providing enough current.

 
Sponsored Links
cheese's Avatar
Forum Topic Moderator

Join Date: Jul 2001
Posts: 16,573
GA

06-20-14, 12:58 AM   #2  
If you put grease on the area where the flywheel key goes, I can't imagine it isn't sheared. If it isn't, it will be. Take it off and clean the grease off the flywheel and the crankshaft before going further. If the flywheel key somehow isn't sheared, your camshaft is probably out of time.


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

God bless!

 
Charliegates's Avatar
Member

Join Date: Jun 2014
Posts: 44
FL

06-22-14, 02:03 PM   #3  
The key is not sheared. Also, the cam is in time because it is lined up with the dot on the crank shaft gear. I did a compression test and I only got 30 PSI. It may be the valves, but they open and close fine in sync with the piston. Here is the video I took so you could better see: https://www.youtube.com/watch?v=NkgG...bcApQC8puuuzEg. Also, the flywheel and crank shaft are pretty difficult to move by hand without leverage. I took apart the engine including the wheel, clutch, and crank case cover, and it is still difficult. I think it is either the cam, or the other side of the engine bore stopping it, because the shaft has some horizontal play.

 
cheese's Avatar
Forum Topic Moderator

Join Date: Jul 2001
Posts: 16,573
GA

06-22-14, 07:23 PM   #4  
How have you verified the key isn't sheared? Did you take the flywheel off and clean the grease? If not, you won't get it running, it will shear.


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

God bless!

 
Charliegates's Avatar
Member

Join Date: Jun 2014
Posts: 44
FL

06-22-14, 07:48 PM   #5  
I removed the clutch, then the washer, then the flywheel. I held the intact key in my hands. Then I cleaned it.

 
cheese's Avatar
Forum Topic Moderator

Join Date: Jul 2001
Posts: 16,573
GA

06-22-14, 08:21 PM   #6  
Okay, good enough, I just wanted to be extra sure before looking into other areas.

The valve operation appeared to be correct.

What kind of spark plug are you using? I didn't re-read... are you using a new plug? When you say you see gas on the valves and piston, how much gas? There shouldn't be much visible.


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

God bless!

 
Charliegates's Avatar
Member

Join Date: Jun 2014
Posts: 44
FL

06-22-14, 09:04 PM   #7  
Did they seen to seat right? The other forum suggested that they look like they are not seating correctly. So, tomorrow, I plan to grind them down a bit. Also, in your opinion, by looking at the video, does my cylinder looked badly damaged?

I mean, there's enough gas I can look in the plug hole and see it...uhhh, a thin layer, I guess? It's just hard to judge the exact volume when you can't see it all. But I know it's getting there. I'm using a spark plug that's less than a week old, it's a champion plug. But see, it's either valves or my cylinder causing my low compression I'm sure. I replaced everything else that would cause compression loss, I do beleive.

 
cheese's Avatar
Forum Topic Moderator

Join Date: Jul 2001
Posts: 16,573
GA

06-22-14, 09:47 PM   #8  
I can't really tell if they are seating right or not. Measure the valve clearance and see. Do the valves look like they have been seating well with a bright ring all the way around the mating surface? If you put new rings in this engine without doing anything to the cylinder, you are probably losing compression there too.

What did the ring end gaps measure?


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

God bless!

 
Charliegates's Avatar
Member

Join Date: Jun 2014
Posts: 44
FL

06-23-14, 11:41 AM   #9  
The valves hold water and the clearance does check out for both of them with feeler gauges. Oddly enough, I was going to reseat them, but they rented me the wrong tool (overhead valves) so I will see if needle nose pliers will do the job.

I never did measure the gap. I installed new rings and what I can say is that they make the fit much tighter inside the cylinder than with the previous rings. To the point where the crank shaft is difficult to move by hand without leverage.

If reseating the valves does not work, then the next step is to recheck how I installed the rings, for I may have made the gaps overlap each other, but I cannot be sure. I did not have the tool for the rings, so I used jewler screwdrivers. That will be the next step after the valves. Any ideas?

-Thanks, Charlie.

 
Search this Thread