View Full Version : Briggs Carb Question

matthew horner
04-05-2007, 08:18 PM
I inhereted a john deere sabre with a briggs inteck motor. The mower had been left out, with the air filter off the carb, so it was full of water, acorns, and a years woth of trash. I took it off and cleaned it up really well, and I replaced the float and needle valve, fuel filter, air filter etc.

Well, when I crank it, it just "puffs". One puff per stroke, high pitched. And this is with starter fluid. It is firing, but not really firing, or going on its own.

Would I be better off just grabbing a new carb?


04-05-2007, 09:05 PM
You should be able to have it start and run for a few seconds on the starting fluid until it burns it up. I use carb. & choke cleaner for this because it doesn't dissipate as quickly. It sounds like possibly valves not seating (surface rust) or possibly dried out carbon broke loose and got under a valve. I believe I would do a little more checking before spending 60/70 bux on a carb.

matthew horner
04-05-2007, 10:34 PM
Thanks restro. You wouldn't happen to have any literature available for posting on the valves on this motor would you> its an inteck.

Bill Kapaun
04-07-2007, 10:07 PM
If it's an OHV engine, you can easily remove the valve cover and check to make sure the valves are moving, instead of being stuck open.

PS did "etc." include the spark plug?
With the carb being "open", rain could enter the carb, run into the cylinder (rusting things up) and eventually into the crankcase, especially if the intake valve happened to be open.

matthew horner
04-07-2007, 10:40 PM
Bill, thanks,
yeah, I want to check those valves, and am trying to find the best way.

By the way, its a vanguard, not an Inteck. So, i'll just need to get to those valves. Yeah, there was water in the crankcase. I had do drain and flush everything etc.


Bill Kapaun
04-07-2007, 10:55 PM
Thinking about it a bit more-
Either valve could be in a rusted open position. When you remove the valve cover, look for an excessively loose push rod. Also make sure the valves move. You may need some penetrating oil on the stems to free them up, IF stuck.

04-08-2007, 08:14 AM
and am trying to find the best way.

Hey Matt, Did you get my last PM ?

matthew horner
04-08-2007, 08:58 AM
Restro, sure did, I'm getting it all together to take it out to the shop.

Thanks for the help my friend.

matthew horner
04-08-2007, 02:10 PM
Bill and Rob.
I took the valve cover off, and turned the motor. Both valves are moving, but there is also a point at which both valves appear to be not so tight (as in I can move the rocker). What can I do from here, to further diagnose/fix this, before I go to the trouble of removing the head? Can I take the rockers off and move the valves around in the hopes of freeing any carbon/rust?


PS-Bill, I got the kawasaki going. I adjusted the choke a bit, and it sure helped. Thanks a bunch for that.

04-08-2007, 03:02 PM
but there is also a point at which both valves appear to be not so tight (as in I can move the rocker)

If you look at the valve adjustment procedure that is in the top dead center area and is somewhat the area needed for adjustment.

I really don't know what you can do on the outside in way of seeing/checking the valve seat area for rust/carbon without a leak-down tester and even doing that test could lead to the head removal anyway.

I would just go ahead and pull the head, Follow the instructions I sent and you shouldn't have any problems. If so all you have to do is shout !

Bill Kapaun
04-08-2007, 06:14 PM
DO you know the reason it was left out?
Maybe it's because the engine was already shot??
Maybe ran without oil or ?????

04-08-2007, 07:48 PM
No there is no way to know in this situation. This guy goes to sales and buys big lots of things and then resales them. He had bought 40 golf carts and then sold them all for 2 - 3 hundred profit each when I went there last week. So he knows nothing about about its history. Therefore if I think it would be worth $800 in working condition I better only bid half that or less on the risk that there is some major thing wrong.

04-08-2007, 07:52 PM
Sorry - posted in the wrong thread above. Woke my computer up and thought someone had responded to my Bunton wheel motor thread.

matthew horner
04-08-2007, 10:57 PM
Bill, just neglect, nothing else.

Lawn Killer
04-11-2007, 02:15 PM
hello to every one

I have a problem with my garden tractor (riding lawn mower).
It is a cub Cadet 2521 with a 54" deck, it has a 21hp vanguard Model 381774: Type 0306I7: Code 03122211: Family YBSXS.6272HN 274838.
My problem is last weekend I tryed cutting my grass with out it spring service. After about 30 min to one hour it started to make a smoke cloud soo thick Jame Bond would have been proud of. The motor stared to loose power and then died. I not knowing what to think tried to restart it and it fired right up with out the smoke cloud and I continued to cut my yard some more. Ten mim later is created this smoke cloud again and I trurned off the PTO and the motoer kept running the cloud stoped and I again reingaged the PTO and kept cutting. LOng story short I now have gass mixed in my oil (but it is not bubbling on the dip stick) I smell it. and I found oil in the air cleaner area. Did I blow this motor up or can I save it. It is 1300 for a new motor but I only got two season out of this old motor. I hope I did not do any major damage to it and the repair needed will not be to difacalt so I can do it and save some $. Cub Cadets are not cheep to get work done on them.
Anyway I thank ever one in adavance for their help.

Bill Kapaun
04-11-2007, 02:49 PM
Sounds like a piece of crud is lodged in the carb needle & seat preventing it from shutting off gas flow to the carb.

Lawn Killer
04-11-2007, 03:12 PM
Sounds like a piece of crud is lodged in the carb needle & seat preventing it from shutting off gas flow to the carb.

How would one go about fixing this? Would I need a Carb rebuilt kit or can I get just a few gaskets and try to clean out the Carb.
Or would a good Carb cleaner spray will work?

04-11-2007, 09:22 PM
Restrorob I placed a post in the Briggs carb form can you pop over and take a look at it instead of me rewritting it again?

Hmmm, The model number on your engine is 381447.

It's sounds as Bill stated, Probably a piece of trash or float sticking (gummed up) from sitting.

The carb. has to come off to get the float bowl off. Hopefully you can get to the intake elbow bolts and remove it with the carb. If not you got your hands full removing the whole intake on that tractor.

Since this one is going to be some what a pain I would suggest replacing the float needle valve part# 808798 $11.80 and the rubber bowl gasket part# 693711 $10.85, You may also want to have the two intake elbow gaskets part# 690950 $2.35 ea. on hand in case they tear on removal.
A complete carb. kit is $57.95 and you really don't need everything in the kit.

Use a can of carb & choke spray cleaner (Not Gum-out brand) with the little straw and spray through ALL little ports and passages good and the fuel inlet port. Reassemble but before hooking up the fuel line check the tank for trash and clean if needed then flush the lines and replace the fuel filter.

Change the oil and plugs then you should be set to go. But, With the fuel over filling the crankcase it has probably filled the muffler also. So be prepared for it to smoke until all is burned out of the muffler.

One last thing, Should you have a problem in the future start your own thread. Most people won't even look at the old ones.

Good luck

Lawn Killer
04-12-2007, 03:07 PM
Thank you both for your help and it looks like I lwill be working on this puppy this rainy weekend.

As for starting a new thread, thats what I will do.

Again thanks.

Bill Kapaun
04-12-2007, 04:16 PM
Why not Gumout?
Curious minds......

04-12-2007, 07:34 PM
Why not Gum-out?
Curious minds......

Well Bill,
I had a carb. job one weekend here at home and was out of cleaner. I drove 24 miles round trip to get some. The store was out of the brand I normally use so I bought two cans of Gum-out at more $. That stuff wouldn't cut the varnish, I read the label and found it to be basically mineral spirits in a pressurized can.
With another 24 mile trip I took it back and went to another store for a different brand.

If there is any doubt to what I found, Next time anybody goes to purchase any do as I do.
Spray a little on your finger and rub them together, If it evaporates quickly thats what you want. If it feels oily and sits on your finger and you have to wipe it off thats the brand to leave on the shelf.

Bill Kapaun
04-12-2007, 08:04 PM
I was curious. I haven't bought any in several years.
I know a lot of similar products have been basically "neutered" because of EPA etc.
Hoppes #9 (gun cleaner) comes to mind.

Lawn Killer
04-13-2007, 11:09 AM
Rob and Bill
Can one get more power out of this Vanguard motor?
With a Briggs one needs to have the thing floored to get the max power.
I have a mix of thin to thick stem grass in my yard and some times it take three passes to get it all cut.
The blades are kept sharp and the deck is maintain.
Other than borring out the cynlender and putting lager pistons what else can one do?


04-13-2007, 01:19 PM
You need to check your no load high speed RPM with a tachometer, Factory spec. is in the 3600 range. You can adjust it up to 3750 no load which would give you about 3550/3600 under load and the rated h.p.
If the RPM is raised to 3750 it's best not to run at full throttle unless under load mowing.

Also, These engines are designed to run at wide open throttle all day long so don't skimp running at 1/2 to 3/4 throttle as some people do for they are not putting out the full rated h.p.

Bill Kapaun
04-13-2007, 06:13 PM
Keep in mind, max torque is in the 2400-3200 RPM range.


matthew horner
04-14-2007, 12:24 AM
I pulled the head.

Vavles look great, not rust or anything stuck. However, one of the pushrods had a slight bend in it. Would you repace the pushrod and the gasket and put it all back together again?

Is there anything specifically I should check while I'm at this point?
Thanks all,

04-14-2007, 09:15 AM
If you have the valves out of the head put the one that was with the bent pushrod in a drill then spin it up. Watch the head for any wabble.
If the valves look OK and the cylinder bore looks OK (no scratches or gouges) replace the push rod and head gasket then re-assemble.

04-14-2007, 09:28 AM
Also Matt, Put a coat of oil on the valve stems before installing them back in the head.

matthew horner
04-14-2007, 09:34 AM
The valves are still in the head, I just took the head off and cleaned it to look it over. I kept the head bolts in order, but unfortunately both of the push rods fell out (dang) so I don't know which valve the bent one goes to. I'll take those valves and spin them like you recommended and will go from there.

Thanks again, you are a wonderful help.