Jump to content

Unofficial Home of Old Simplicity & Allis-Chalmers Garden Tractors

Calling All Engine Guru's


Spencyg

Recommended Posts

The saga continues with my extremely aggrivating briggs 16hp rebuild. For those who are just joining in, I recently rebuilt my 16hp single cylinder cast iron briggs after discovering broken rings and a mangled piston when disassembling. After putting it all back together, and then installing a new battery fired coil (replacing the magneto) I was able to get it running today. I have a couple of problems/questions. 1) The mechanical govenor will absolutly not let the engine go to idle. I have the springs set up like described in another post, and adjusted as well. Could I have installed this thing backwards? It doesn't seem possible, but I'm open to suggestions. When the engine starts, the govenor arm raises, and it requires force to push it down instead of pulling it up. I'm confused. 2) The engine will not idle without the choke fully on. If I slowly work the choke in the engine will start sputtering and die. I have tried adjusting the idle air valve in and out, but it doesn't effect anything. If I start to raise the throttle (by manually holding the throttle shaft), it obviously goes rich until I slowly open the choke to suit the engines needs. If I open the choke too much, it will die again. The engine starts easily (which choke fully on), and seeems to idle well. With the higher throttle settings there seems to be some missing, but I'm sure that can be traced back to the choke problem. What do you guys think? This is really getting aggrivating. Please help!!!!!!!!!!!! Spence
Link to comment
Share on other sites

Sounds to me like an air leak past the throttle shaft or a bad carb gasket. It is starveing for fuel. It needs the choke on to create enough vacume to draw in the gas. Could all so be dirt in the fuel circuit in the carb.
Link to comment
Share on other sites

quote:
Originally posted by UCD
Sounds to me like an air leak past the throttle shaft or a bad carb gasket. It is starveing for fuel. It needs the choke on to create enough vacume to draw in the gas. Could all so be dirt in the fuel circuit in the carb.
Maynard, it's starving and vacuum:D. I'll take a long shot that both gaskets between the carb and baffle plate are not in place. It's kind of tricky to get that all together.
Link to comment
Share on other sites

Both gaskets are new & in place Bob. The throttle shaft has a bit of play, and the fuel bowl gasket might be bad...I'm not sure. It wasn't leaking fuel, but that doesn't mean anything. Any thoughts on the governor? Spence
Link to comment
Share on other sites

Just because they are new doesn't mean they are not leaking air. Having to use the choke to keep it running at higher rpm tells me you have a carb/fuel problem.
Link to comment
Share on other sites

Originally posted by Spencyg:
quote:
1) The mechanical govenor will absolutly not let the engine go to idle. I have the springs set up like described in another post, and adjusted as well. Could I have installed this thing backwards? It doesn't seem possible, but I'm open to suggestions. When the engine starts, the govenor arm raises, and it requires force to push it down instead of pulling it up. I'm confused.
Are you saying that the governer arm pushes up, releasing tension on the governer springs? I can't think of any possible way for this to happen unless the governer arm is installed backward (pointing away from the flywheel). I don't think there is any way that you can install the governer itself, backwards. The fuel problem that you describe definately sounds like an air or vacuum leak as has previously been suggested. Pat
Link to comment
Share on other sites

Try using shaving cream to detect a vacuum leak. The foam will get sucked in if there's a leak.........
Link to comment
Share on other sites

I would agree with the other post that you have a air leak. Like UCD said just cus your gaskets are new doesn't mean you wont get a air leak. I would check you gaskets and maybe put some permatex on them. also if your throtle shaft has some play in it could cause you problems. try finding some felt bushings are which most had.
Link to comment
Share on other sites

I suggest (just in case it is an air leak) using some permatex aviation gasket sealer on both sides of the gaskets. If there is a leak, this will fix it unless the intake manifold has extremely warped ends. By now, your spark plug is probably gunked up or fouled so cleaning or replacement may be a good idea before trying to start it again. Why did you go with a battery fired coil? The standard magneto with a electronic ignition conversion module works great on one of those engines. Sounds to me like it could be dirt/gunk in carb or faulty ignition components (plug, wires, timing off). Good luck.
Link to comment
Share on other sites

Also, on the governor, did you do the steps to get the correct gover to carb relationship that I posted. I this is not correct, the engine will wonder in RPM, generally up as the governor weights are out of the playing field and have no control. You have two seperate problems. You have to get your carb problem solved for the lack of fuel. After that is taken of you have to get your governor back in syc with the carb.
Link to comment
Share on other sites

I adjusted it just like you said Bob and the arm just wants to push up (holding the carb wide open). I will try sealing the gaskets better. I looked at an exploded view of the governor, and there really isn't any way I could have screwed up the installation. This is so aggrivating:) Spence
Link to comment
Share on other sites

A governor is basically an automatic throttle control. The carb. has to be adjusted right before the governor can work right. Disconnect the governor and get the carb working and adjusted then hook up the governor and adjust that.
Link to comment
Share on other sites

Well...I ordered a carb rebuild kit from Jacks Small Engine last night. I took the carb apart yesterday, and the main bowl gasket was junk, leaking fuel from the bowl and everything. Hopefully this will be the final purchase, as this rebuild has already doubled my proposed tractor rebuild budget. The wifey-poo isn't a happy campder:) Spence
Link to comment
Share on other sites

Governer Update: I pulled the engine again last night (for the umteenth time) and removed the oil pan. Upon initial inspection the governor seemed to be all together correctly, but when I removed it from the block it was obvious that the plunger that is operated by the centrifugal weights to move the level op and down was stuck. I punched out the pins holding the cent. weights and removed the plunger to find that for some reason the shaft that the plunger rides on was all mangled (not from my doing..). After 15 minutes with a file and some emory cloth it was moving smoothly again and reassembled in the engine. I am sure that it will work just fine now. By the time this is done, I will be a walking-talking 326000 series engine encyclopedia:) Spence
Link to comment
Share on other sites

Guest
This topic is now closed to further replies.
×
×
  • Create New...