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chadinabnit

Still Can't Get My 725 Running

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chadinabnit
Still can not seem to get my 725 to run. Had a friend take a look at it and decided it was a fuel issue with the old carb. Getting good spark and compression, just wasn't getting fuel. So I purchased a new carb and put it on Saturday. Got it running a little just could never get it smoothed out. I have done all the trouble shooting that I can think of with this. Just don't know where or what I need to look at now. Anyone know what else we could be looking at here causing this thing not to want to run?

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mbinwi
I need to do this governor adjustment to my 700. I watched Zippo's You tube thing and he says turn the screw clockwise, and the link to Dan's article says to turn the screw counter clockwise. While holding the throttle open, which way do I turn the screw? Also, I only have one spring to the governor arm. Am I missing one? The manual I have looked at shows one spring. Zippo's video has two. I'm confused, or am I making this more complicated than it is?

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chadinabnit
We worked on this again last night. We still think it is a fuel/air issue. Can't seem to get it to do the same thing twice. Get it to run one way a little, make a small adjustment and it won't do anything. Feel like it is getting to much air and not enough fuel.

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perry
bad condensor ? check points, clean , then reclean and gap points. check wire connections. change the spark plug even if you just change it recently. is that a used carb you bought ? make sure it's clean. make sure gas tank and sediment bowl is not plugged. weak ignition and also valves could be out of adjustment ?

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BLT
Here is how Al Eden posted the govrnor adjustment. We are all talking the same language. When facing it you move CCW for the off position adjustment and the throttle plate moves in the CW position for WOT. "Hi, One of the most confusing items for many people is setting the governor linkage. This method works equally well for both Briggs and Kohler and Others. When you open the throttle with the engine dead it hould pull the carb wide open. Watch the governor arm. Move the arm back and forth, the carb will go from idle stop to full open. Next either open the throttle or hold the governor arm so the carb is wide open. With the arm held like this, loosen the bolt that clamps the governor arm to the governor shaft. With the arm still in the carb full open position, TURN THE GOVERNOR SHAFT AS FAR AS IT WILL TURN IN THE SAME DIRECTION IT ROTATES WHEN IT OPENS THE CARB. TIGHTEN THE CLAMP. Your governor linkage is now properly set. Many books say turn it colckwise or counter clockwise depending on the engine. It is so confusing to try to remembeer that stuff. Just remember it ALWAYS turns in the same direction it turns to open the carb, and it is always set with the carb wide open. This takes all the slack out and presets everything. This is what they try to tell you, they choose a hard way to remember it. This is how they taught us in Briggs factory school. Good luck, AL" Also, Chad spray some carb cleaner around you joint areas. If you get any variation of engine running indicates that a gasket might not be in place.

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chadinabnit
I am pretty certain that I am getting good fuel flow. I replaced the fuel filter. I am thinking that I not getting a good seal somewhere and it is sucking to much air. We just can't seem to get it to do the same thing twice.

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chadinabnit
We are getting a good flow from the lines. The bowl on the carb is being filled like it should, just doesn't seem to be getting anything from there up into the intake and motor.

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GLPointon
Is the carb "new"? or used or rebuilt? To try to troubleshoot online its all in the details. Has the carb been set to starting adjustments? (needlevalves, float, idle, etc) Is the headgasket good, headbolts tight. When it does run, how long? does it die? will it restart right away? is the gas tank vented (proper cap) All these questions are to determine if its a fuel issue. If its a gov. problem then you should be able to keep it running with your fingers on the carb throttle, because the gov. just controls the throttle. If it dies regardless then if may be losing fuel supply or ignition system failing, or valve/mechanical issue. I would replace all the "cheap stuff" ie: points, CONDENSOR, spark plug, make sure ignition wire isnt being cut by point cover. If you can give all these answers it will help... (I know its frustrating as heck) but it will be worth it in the end... Good Luck...sm01

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BLT
There are three gaskets used in mounting the carb. Two are pretty obvious. The third one is between the shield and the block and oftened missed.
[img]/club2/attach/BLT/19 intake.jpg[/img]
Double check that.

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chadinabnit
Yeah, we did notice that one. I disconnected everything and removed the plate. We bolted on the carb without the plate to see if that was the issue but couldn't get much more done. It ran a little but started to rain. I was checking it Friday afternoon just to see and could feel air coming from around the intake. We are going to reseal everything there and try again. Have to pick up some good gasket material tonight.

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chadinabnit
Finally got some life out of the motor the other night. Replaced both seals to make sure that we were not getting an air issue there. Fired up pretty easy after that, but would not stay running unless you had almost full choke on it. Going to make a new seal for the carb because we did not like the way it was. It was nice to actually hear it run and idle if only for a few minutes. Getting there slowly, hopefully Saturday we will get it completely figured out.

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Brettw
Could this be the dreaded sheared flywheel key? If so, you would have compression, and you would have spark, but the spark would be at the wrong time in the stroke. If this be the case, they do run all kinds of strange, if they run at all, and heat will affect them, load, just about anything. I would find it strange that you have such a huge leak at the manifold gasket as to affect running or starting to the degree that you are. Just a thought.

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chadinabnit
We have started with the simple stuff so far. We plan on taking the head off and checking the valves on it and will also take and check the key to make sure it has not sheared. Just doesn't seem to be getting proper fuel flow into the chamber.

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AC82
One thing I can think of that hasn't been mentioned yet is tapping on the carb bowl to see if the float needle is sticking. The float being stuck could definitely cause erratic results when trying to adjust needle valves.

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chadinabnit
We took the head off on Saturday and replaced the head gasket. Took the valves out and checked them. We ended up lapping the valves to clean them up. We can get it idle pretty smooth just having issues when trying to rev it up. Will not stay running then. We adjusted the governor also per the instrustions. Just going to keep playing with the carb settings to see what we can do.

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powerking_one
Chad, At this point, I would say your magneto coil is bad. The symptoms all fall in line with these problem prone Magna-Matic ignition systems that Briggs used in the early/mid '60's. My brother had a model 23 Briggs generator we troubleshot and it had the same symptoms; it would start & idle ok but upon revving it up, it would just die. The coil was bad. Also the plastic/rubber covering of it was kind of mushy indicating insulation breakdown. Once the coil was replaced, issue solved. Tom (PK)

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chadinabnit
We haven't checked the coil on it. I noticed that the coil is no longer available on Jacks when I was trying to look up the pricing. Do you know what you replaced the coil with so I can check into finding one if I would need to get one.

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powerking_one
Chad, I believe it is B&S PN 290880 and is no longer available O.E.M. The one my brother got was off eBay in the $20 price range (Chinese knock-off, but it worked/fixed the ignition problem). http://www.ebay.com/itm/COIL-fit-BRIGGS-STRATTON-Models-9-14-19-22-23-23A-B-F-R-/380457562161?pt=LH_DefaultDomain_0&hash=item589509b031 Do a search on "ePay" for -deals- like this also "Briggs 290880": http://www.ebay.com/itm/IGNITION-COIL-FOR-BRIGGS-AND-STRATTON-290880-/250831093698?pt=LH_DefaultDomain_0&hash=item3a66b2bfc2 Tom (PK)

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chadinabnit
Tom, We pulled the motor on Saturday and took it apart to get at the coil. The insulation on the coil was very mushy and it appears to be our issue. Going to order a new one and go from there. I think we are finally getting there though.

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