Shop Products
Houzz Logo Print
ih8tbugs

Briggs & Stratton Getting Spark & Fuel - Won't Start

ih8tbugs
14 years ago

I have a B&S 13.5 Horsepower Model: 313777 I've been working on this thing for days. Had the cap fall off the valve somehow and put it back on and adjusted the valves. It is getting fire and fuel, but it won't even act like it's going to start. If I pull the choke on the cold engine it gives too much gas and starts popping through the exhaust while cranking. Holds 80 lbs of air for at least thirty minutes - didn't check any longer, but it wasn't leaking a whiff of air for that time. I'm getting ready to go check again, but I've been getting no compression while cranking before I adjusted the valves. Pretty sure I got the adjustment correct following the Briggs service manual, 1/4" past TDC compression stroke. Never adjusted valves on small engine before, so I could be getting this wrong. Any ideas on what could be wrong?

Comments (6)

  • mownie
    14 years ago
    last modified: 9 years ago

    OK, can you post the Type number also (found in the same place on engine as the Model number). You have to know Model and Type numbers to view the online manual and IPL at the Briggs website. When we are able to view the Illustrated Parts List for your engine we may be able to determine what you are calling a "cap" and then proceed with repair instructions. I can tell you already that you need not crank the engine any further until a proper valve adjustment has been done. The procedure for adjusting the valves is not difficult to perform. In fact, you have already touched most of the parts involved in the procedure, but you have not actually performed a valid valve adjustment because THAT requires the engine crankshaft be stopped at precisely the right point AND that the valve clearance be to a precise value. We can get you the instructions after we know more of which particular engine you have. I would like for you to explain what you are referring to in this next sentence please: "Holds 80 lbs of air for at least thirty minutes - didn't check any longer, but it wasn't leaking a whiff of air for that time." What are you doing or using to draw the conclusion that it "holds 80 lbs of air"?

  • ih8tbugs
    Original Author
    14 years ago
    last modified: 9 years ago

    I applied 80 lbs pressure to the cylinder with the valves closed. It held that rate for 30 minutes. Was trying to rule out leaking valves - bad ring/cylinder. I'm still getting no compression while cranking even after I adjusted the valves per the Briggs service manual for this engine and it still holds the applied pressure 80 lbs. with valves closed, which I just got finished checking once again. The cap, pops onto the end of the valve stem. The Type # is 6112-E1, unless that 6 is a G, so either or.

  • ih8tbugs
    Original Author
    14 years ago
    last modified: 9 years ago

    OK, I see that that is one badly stamped 0 and not a 6 or a G. :( So type is: 0112-E1

  • jgreissi
    14 years ago
    last modified: 9 years ago

    I'm guessing the "cap" is the keeper on the valve? parts falling off of the valves are not good. Do the valves go up and down as the engine turns? You could have a lobe of the cam wiped out or if it is one of those steel cams with the attached nylon gear, the gear may not move the cam. Start with basics first. No compression with a good leakdown means that the cam is completely out of phase, or not moving. Once you figure out what the major problem is, then you can worry about adjusting the valves.

  • mownie
    14 years ago
    last modified: 9 years ago

    OK, I see in the IPL that item # 238 (Briggs # 691843) is the cap you referred to. Thank you for outlining the part about "holds 80 psi". Now that you have confirmed what I thought you meant, I need to ask, is 80 psi, the pressure you are applying to the cylinder (I presume you have an adapter air fitting threaded into the spark plug hole) with an air compressor, or is the compressor SET AT A HIGHER psi........and 80psi, is all the cylinder will maintain? I hope you understand what I am asking but let me put it another way. While you have the source of compressed air connected to the cylinder, does the air compressor cycle on and off to rebuild air that is leaking off "somewhere"? If the air compressor DOES cycle on and off, but you don't have any air leaks in your compressor air hose or plumbing, then the air must be leaking out of the cylinder somewhere. An "air leakdown test" is not simply to connect air to the cylinder and see how much pressure the connected air compressor is capable of maintaining (on the gauge). An air leakdown test must really be done with a gauge that "measures the PERCENTAGE of leakdown, even a "good cylinder" has "some leakage". It is neccessary to determine if the "actual leakage" exceeds the "allowable volume (%) of leakage" An air leakdown test is also conducted to determine WHERE the air is leaking from (valves? piston or rings? head gasket?). So, your answers to the questions of just how you are achieving the "80 psi for 30 minutes" will allow us to get past that issue as you may well be getting a false indication of "health" from what you have been doing there with the air pressure. During an air leakdown test, you should be listening to for air escaping into the exhaust system, or the intake manifold, or into the crankcase. Of course, the crankshaft must be stopped at the correct position AND HELD there so it cannot turn when the air pressure is applied to the cylinder. To "listen" for escaping air, I use a 2 foot length of plastic tubing (5/16" or 3/8" diameter, at auto parts store or plumbing supply). Place one end of the tubing into the muffler or exhaust port (if muffler is removed) and hold the other end close to your best ear. Any air leaking past the exhaust valve will be heard through the tubing. To check intake valve, place one end of tubing into the carb throat (with throttle wide open) or intake port (if carb is removed). Air escaping past the intake valve will be heard through the tubing. To check for air escaping into the crankcase (because of piston, rings, or head gasket defects), take the oil level dipstick out and listen for escaping air coming from the dipstick tube, or you can hold a small "flap" of tissue paper over the open dipstick hole, if significant air is coming out of the dipstick hole, it will lift the tissue off the hole. Wipe off the dipstick hole before laying the tissue in place so it won't just "stick" to any oil. OH YEAH, please post here and ask Mr. Walt Conner to post his "cryptic" e-mail address so you can contact him for HIS instructions on adjusting the valves. Walt is one of the primary Briggs contributors on this forum and most times Walt's instructions are better than Brigg's. It would not be "proper" for me to "set you up" with his e-mail as Walt has his own way of handling that. However, if you search in this forum and find a post where Walt "furnished" his e-mail address to another member, I'm sure he would be OK with that. It's just polite and PC to "ask first".

    Here is a link that might be useful: 313777 IPL

  • walt2002
    14 years ago
    last modified: 9 years ago

    Thanks again Mownie but I question whether the hp or model number is correct.

    Walt Conner
    wconner5 at verizon dot net (put in proper format)

Sponsored
Fresh Pointe Studio
Average rating: 5 out of 5 stars4 Reviews
Industry Leading Interior Designers & Decorators | Delaware County, OH