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Welcome input on this.
This mower is a very old 22" Poulan Hi Wheel push Mower (originally sold as Weedeater model) with a Briggs 6.5hp engine. It has one of those 4x5 plastic plates that holds the primer bulb and the PVC hose connector (from valves cover) and this whole plate bolts to carb.

After shutting engine off I heard a bubble noise coming from mower when I pushed it in garage. I noticed some gas leaked down on mower deck under air filter area. I pulled the air filter and it was soaked with gas.

I'm thinking the float bowl needle valve seat has worn a leak but also got to wondering if maybe something has gone bad with my engine valves causing excessive blow by coming thru PVC tube into carb area. But that wouldn't make the gas leak would it ?

Anyhow I've already ordered a rebuild carb kit since it's due one anyhow. But welcome any input on what else might be causing this.
Thanks.

Yes am sure we can give you answers if you post up the engine numbers.

EngineMan said:

Yes am sure we can give you answers if you post up the engine numbers.

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This mower is close to 30 yrs old. There's no engine number on it that's readable. I have a ticket from an old trip to a local parts house that says they ordered parts for it under Briggs Engine Model 12J802, Type 3135. And the parts worked so I guess that's close enough.

The Air Cleaner Primer Base plate that I spoke of looks just like Briggs OEM 795259 part.

Anyhow I'm cleaning up the carb and have ordered the rebuild kit and the Air Cleaner Base plate which includes a new bulb since the old one looks rough. This has been probably the most dependable mower I've ever owned and I've owned a long time.

Primer System carb one of 498966, 498170, 497347 before giving more answers apart from give it a good clean out before fitting all the new parts and it should fine after that, if not let us know and we will take it from there.

It may also be time to check the valves....they may need a lapping...!

EngineMan said:

Primer System carb one of 498966, 498170, 497347 before giving more answers apart from give it a good clean out before fitting all the new parts and it should fine after that, if not let us know and we will take it from there.

It may also be time to check the valves....they may need a lapping...!

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The mower is so old I've never really had (or lost) the OEM Nomenclature numbers on it. I bought decades ago at a big box store. Always had to feel my way along with part orders. I've never ordered a new carb (yet) just always rebuilt it with Briggs OEM 498260 Carb Kit. Many carbs look very close except for throttle linkage lever length. The carb on mower does have a readable number 8823 0209 stamped on backside of carb flange on engine side flange. Never found any with this number ref for sale. In one ebay pic I found it looked identical (throttle level etc) to the Briggs 8823 8257 carb.
However listings show the Briggs OEM 799868 Entire new Carb, replaces Briggs 498254, 497347, 497314, 498170 but the pics don't show the exact same linkage lever. I will rebuild it again this time.

I need a little help on the lapping thing. I've adjusted the valve lash on my JD tractor as it has adjusting nuts. But I've never got into any of my push mowers. They don't actually have adjusters do they ??

If the engine compression is good then leave the lapping for now, do the repair on the carb to see if that helps with the problem you have, lots of videos on youtube doing the valves if you need to do them.

My rebuild kit came in, I've cleaned the carb and put the new stuff in. I have two questions at this point.

1. What is the Round Tin Plate looking thing that's in the bottom of the carb (top of bowl area). It looks pressed in (?) and there's also one in the rebuild kit. I've never removed these before, is this something I should remove and check or clean behind it?

2. Also the Float Bowl attachment screw (which also looks like it feeds the high speed jets). The screw has a Tee type passage orifice. The horizontal passage is large enough to get a small pin in to clean it out. The vertical passage however is so small I cannot even get a needle through it. How do you guys clean this?

I did squirt some PBlaster in it and then blew it out with the compressor. Then I blew on it the vertical and I could feel air coming out the horizontals so I guess it's ok.

That round object you are talking about is a welch plug... No need to worry about that unless your carb is extremely dirty or corroded........

Yes the bowl nut is your main jet...... You can get a bread tie with the plastic taken off of it and get it thru that top hole.... Use carb spray instead of PB Blaster..... Wal Mart has carb spray for 1.75 a can.........

Take the seat out also and replace it as well.. A crochet hook works well... I snatched my wife's small one and it works perfect......

Put the new seat back in groove side down in the carb.... Flat side facing needle.....

Here's a video link in case you need it...........

https://youtu.be/kJfpTX2Lx0g

Boudreaux In Eunice La. said:

That round object you are talking about is a welch plug... No need to worry about that unless your carb is extremely dirty or corroded........

Yes the bowl nut is your main jet...... You can get a bread tie with the plastic taken off of it and get it thru that top hole.... Use carb spray instead of PB Blaster..... Wal Mart has carb spray for 1.75 a can.........

Take the seat out also and replace it as well.. A crochet hook works well... I snatched my wife's small one and it works perfect......

Put the new seat back in groove side down in the carb.... Flat side facing needle.....

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Thanks! Now I know what that thing is. My carb was surprisingly clean for such an old engine so I won't bother removing it. I guess regular use tends to keep varnish residue down but the needle seat just wore out and was leaking. I surmise underneath the welch plug is just another orifice passage (?) and it's no longer needed on current carb applications?

Actuall there is a passage under there and it's not sealed completely. When you spray carb cleaner in the right hole yhr spray will come out at the welch plug........

Some techs consider it a vent area......

Boudreaux In Eunice La. said:

Actuall there is a passage under there and it's not sealed completely. When you spray carb cleaner in the right hole yhr spray will come out at the welch plug........

Some techs consider it a vent area......

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Thanks again, ALSO I have a strange thing going on. I fired the mower up today and it ran great, in fact it's running way faster rpm than ever in it's history. Actually it's sounds about like the rpm of my newer briggs push mower but this old one has never ran that fast. Anyhow the kicker is I cannot idle the mower down now.

I got to looking at the governor-throttle spring to see if I got it back on correctly and it looks the same as I remember but it's been a few days. It has a side mount throttle lever (on the carb filter housing) that simply slides toward back of mower for fast and to the front of mower for slow. But now I have no slow, just runs wide open in both positions ?? Kinda concerned bout that. Edit add ( Looking at the pick what do you think? )

(Oops jpeg balked after first load, never would load again. After trying to load the jpeg From Computer button, the screen just sat there forever on the loading files. I finally gave up and closed it out. Not sure what's going on with that. I will try in another reply below.

Your link won't open.......... You have the linkage hooked up wrong or it's in a bind somewhere..

Boudreaux In Eunice La. said:

Your link won't open.......... You have the linkage hooked up wrong or it's in a bind somewhere..

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Ok, I tried editing and reloading the image on the reply above but it refused to load it. So I tried here again on the same From Computer button. Ok this time it appears to have loaded, although the process is a bit ambiguious. The loading screen just sat there for at least 5 min's. I went away from the computer and came back later and the loading screen box was still just sitting there. So I tried clicking the URL button (beside the From Computer button) then the screen immediately went away before I could do anything else. And so far I can see the image in the post.

In any case it appears I'm going to have to take it carb back off and find someplace to hook the linkage to the throttle plate where it has less position leverage so the governor can pull it back more.

Looks if you have the governor rod in the wrong hole....try the other one

EngineMan said:

Looks if you have the governor rod in the wrong hole....try the other one

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Yepper that was it. I switched the linkage to the other orange sleeved hole and now it idles down like normal on slow throttle. It was a bit more difficult to get the carb in a position to insert the linkage into that hole but that's the one it needs. I have another newer briggs mower same size and it doesn't have a throttle (edit add-> i.e. a throttle adjustment) at all. It just runs wide open all the time and shuts off when you let go of the handle. I looked at it's throttle plate lever (that is hooked to a governor) and it has a similar located hole but only one hole period. But there's no adjustment it just cranks and runs pretty fast.

This older mower just doesn't run as fast even on wide open (now with correct linkage hookup) as the newer mower. It gets the job done for the most part though. I guess maybe the older mowers didn't have as strong a valve springs and decided to governor them down more (?) but who knows. It's been running now for 20yr or more.

Edit add, oh and a big thank you to all who replied on this thread.

A photo or photos always give us here much more information then you could say in words...! thanks for the feedback.:thumbsup:

EngineMan said:

A photo or photos always give us here much more information then you could say in words...! thanks for the feedback.:thumbsup:

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As was said many moons ago.... a picture is worth a thousand words !! .. :thumbsup:

Thanks for letting us know.... There is way to get more RPM's out of your mower.......

EngineMan said:

A photo or photos always give us here much more information then you could say in words...! thanks for the feedback.:thumbsup:

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Boobala said:

As was said many moons ago.... a picture is worth a thousand words !! .. :thumbsup:

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Yepper my camera is broken I had to hold the battery case lock down to get that one pic I posted. It's time to get a new camera for sure.

Boudreaux In Eunice La. said:

Thanks for letting us know.... There is way to get more RPM's out of your mower.......

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In the past I've read of bending the tab the governor spring hooks on, to let the throttle lever pull more against the governor, but on this particular mower there is no bendable area that I can tell. I did try stretching the old spring but it still runs rather low rpm compared to most mowers I've used. It's always done that, rather odd I guess but it's been a durable mower over the years. It's so old it might be too much on the old girl to run her any faster now. Always interested in any tricks or tips though.

I remember in my younger years (back during the last ice age) we used to drill out (just slightly) the main jet in our motorcycle carb after putting a lower resistance muffler on. It seemed to run with more power and top end that way. In fact it had more power just with the less resistance muffler. But we were told by the shop tech that we should also drill out the jets cause the better breathing exhaust might cause a lean fuel scenario and in some cases if bad enough might burn a valve over time. Amazing I remember all that stuff. Anyhow the bike did run better and never burned a valve either.

Actually if you stretch the spring you are lowering the RPM's.... The part that the spring is attatched to is bendable.. It doesn't take much to increase the rpm's......

Boudreaux In Eunice La. said:

Actually if you stretch the spring you are lowering the RPM's.... The part that the spring is attatched to is bendable.. It doesn't take much to increase the rpm's......

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Thanks, I stand corrected on the spring stretch, looking at the throttle lever again now I see it would in fact allow the governor to pull it more closed. It seems I get a little backwards in my decipher the older I get. And now that you point out the fact that it wouldn't take much bracket bend to increase rpm a little, (looking at my pic again) I guess I could bend the round (spring holding) tab down a bit. I'm hesitant to bend it upwards since there is a cover that mounts over. I think I will try that, if I can bend it without the whole bracket starting to deform sounds like a plan. Thanks again.

Edit add-> Oh and by the way as for the original issue of gas leaking out the carb, the new needle and seat appears to have stopped that issue. I ran it long enough to heat up good and then turned it off and looked back at it for bout a 1/2 hr afterwards and no leak at all now. Before it was puddling on the deck.