Primer issue

Cfs

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Primer/carb question
I am working on an old Ariens lawn mower model 911014 with a Tecumseh TVS120 63096F engine. Customer brought it to me with a broken remote mounted primer. Snaps into the blower housing (2 legs and a center fitting the hose gos to) Like the ones you see on snowblowers. I put a replacement generic primer that fit and it would not run for more than 3-5 seconds. Figured out that if I plug the hole in the center of the primer that it would continue to run. Seems like the primer bulb begins to expand while running with the plug in it. Must be pressure that is venting back from the carb. Is there a different model of primer that I need one with a check valve built into it? Is there an internal vent in the carb that is blocked? I have checked the fuel drained and refilled it after flushing the gas tank, installed a new needle and seat. I was pulling my hair out until I thought that since the old primer was a solid rubber cover (no center hole) that I should try to block the hole in the new one and Shazam it will stay running

What do you recommend
Thanks
Spit
 

Rivets

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I’m getting confused, so can you provide us with a bit more info. Are you sure the engine has not been replaced? I’ve looked up the model number for your mower and cannot find your engine listed as an original engine. Second the engine you listed uses a carb with the primer mounted on the carb. Can you supply us with the serial number for both the engine and the mower.
 

Cfs

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I’m getting confused, so can you provide us with a bit more info. Are you sure the engine has not been replaced? I’ve looked up the model number for your mower and cannot find your engine listed as an original engine. Second the engine you listed uses a carb with the primer mounted on the carb. Can you supply us with the serial number for both the engine and the mower.
I’m getting confused, so can you provide us with a bit more info. Are you sure the engine has not been replaced? I’ve looked up the model number for your mower and cannot find your engine listed as an original engine. Second the engine you listed uses a carb with the primer mounted on the carb. Can you supply us with the serial number for both the engine and the mower.
The model & serial number for the Ariens mower is 911014 serial 024589. mower. The Tecumseh engine has theses numbers on shroud/blower housing TVS120 63086F. Serial 8302B
I have downloaded an owners manual a parts list and a Service manual for the mower from Ariens website. It clearly shows an engine with a shroud mounted primer and references the model number that I see on the engine. I have just re-checked the everything that I did to the carb. New seat and needle etc all looks good:,,
 

Cfs

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The model & serial number for the Ariens mower is 911014 serial 024589. mower. The Tecumseh engine has theses numbers on shroud/blower housing TVS120 63086F. Serial 8302B
I have downloaded an owners manual a parts list and a Service manual for the mower from Ariens website. It clearly shows an engine with a shroud mounted primer and references the model number that I see on the engine. I have just re-checked the everything that I did to the carb. New seat and needle etc all looks good:,,there is definitely pressure in the primer hose going back to the primer from the carb. If I plug the hole in the center of the primer immediately after starting the mower it will continue to run, if not it will stop running in 3-5 seconds. The primer bulb seems to inflate when I plug the hole in it. if I unplug the hole the engine dies in a few seconds. Somehow air pressure is going backward away from carb to the primer. When I stop I the air flow by plugging it at the back primer I runs….Maybe a leaking intake valve allowing a back pressure to get in to the carb preventing gas from getting into to the cylinder/combustion chamber??? I am for confused as hell
 

Cfs

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The model & serial number for the Ariens mower is 911014 serial 024589. mower. The Tecumseh engine has theses numbers on shroud/blower housing TVS120 63086F. Serial 8302B
I have downloaded an owners manual a parts list and a Service manual for the mower from Ariens website. It clearly shows an engine with a shroud mounted primer and references the model number that I see on the engine. I have just re-checked the everything that I did to the carb. New seat and needle etc all looks good:,,
My fat fingers It is a TVS120- 63096F not 86. Could there be some kind of an oil breather that is not venting pressure this seems to have the Tecumseh type breather not the Briggs style that bolts on over the valves
Chuck
 

Rivets

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When I look up your engine this is the carb it calls for. https://www.partstree.com/parts/tecumseh-632046a. This carb is what is called an internally vented primer system. From your description you also have an internally vented system, but using a remote primer. I’ve looked everywhere and I can’t find this primer bulb. I’ve looked at the Ariens manual and they don’t make any mention of it. Is this bulb mounted on the tank or on the engine shroud? Plugging the vent hole is going to get tricky, as you don’t want to use anything which may eat the rubber. Only thing that might work is a silicone or latex caulk. I’m going to keep looking around but I’m hoping IL, StarTech or Bert will see this thread and chime in to tell me what I’m missing.
 

Cfs

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It is the original engine, the Ariens owners manual I downloaded clearly shows the remote primer mounted on to the engine shroud. The casting of the carb body has the location for a carb mounted primer but it does not appear to be drilled with the passages necessary for a carb mounted bulb.

I used a piece of Tygon tubing to run from the new primer to the carb, twice now after running the engine with the primer hole plugged and shutting it off...when I went to restart it I found that the tygon tubing had split and detached itself from the plastic bayonet fitting on the primer.

It makes me all the more certain that pressure from the engine is somehow venting itself through the carb and out of the Vent fitting that the primer tube attaches to. . When I don't plug the primer this reverse pressure is shutting the engine down by preventing the fuel to flow into the intake. when I pug the hole the flow out of the primer line is stopped, the engine keeps running but pressure builds up in the primer line and causes the hose to split.

Since the carb is only connected to the intake I am assuming that the intake valve must not be seating/sealing completely and on compression stroke some of the exhaust is venting back through the carb and out the vent that the primer line attaches to. Make sense to anyone?
I am trying to process what I am experiencing and this is all that makes sense to me...surely someone else has had a similar experience... Hoping somebody can confirm my conclusions or straighten me out
Thanks CFS
 

Rivets

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This is something I’ve never heard of before. To me I’d like to figure this out or learn from someone who has seen this. Part that really confuses me is I can’t ever recall a Tecumseh carb internally vented with a remote primer. Can you take some pictures of what you are talking about, so we all can see what you have? Use low resolution settings so they aren’t too large to post.
 

VegetiveSteam

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Primer/carb question
I am working on an old Ariens lawn mower model 911014 with a Tecumseh TVS120 63096F engine. Customer brought it to me with a broken remote mounted primer.
Did the customer say if the engine was running fine before the remote primer got broken? Has it been sitting around for quite a while broken or were they recently using it and broke the primer?
 

StarTech

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I am too confused as all the model/spec listed in the parts IPL are carburetor with primers and no indication of a remote primer on those engines IPLs.

Can the OP post the MFG code from the current carb. Maybe I can cross it to the Tecumseh carb PN and then pull it up to cross to engines that used it.
 
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