OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Tecumseh / Kirby Engines Tecumseh Vantage - possible engine breather issue

Hi Guys.
I just cleaned up this tecumseh mower, all pretty standard work despite the mower being overfull with oil and having petrol in the float everything was pretty standard with repairs.
Upon testing the mower simply would not start which I though was strange as it has good spark and everything seemed pretty normal (it ran nicely with full down the plug whole and didnt smoke.
By chance I took the air filter cover off to see what was happening and tried to start it without the foam filter in place. Bang - It started first pull and runs perfectly (that is without the foam filter in place or the cap.
I think the problem is something to do with the breather system as puffs of smoke are coming out of the breather on the air filter when the mower is running.
Could the problem be to do with the mower initially being overfull with oil?
Do I need to clean the breather somehow?
Any help would be greatly appreciated as I haven�t encountered this type of problem before.
Thanks
Jaffa

It does sound a bit strange Peter, though compared with what Paul Foot is going through, you are having an easy time so far.

When you did the petrol-in-the-plughole trick, was the air cleaner fitted? If not, the whole thing sounds like a blocked air filter element. If the air cleaner was fitted, I'm wondering if you had a temporary blockage of the main jet, which has cleared itself. What happens if you put the air cleaner back on, now that you've had it running properly on its carburetor?

Yes Grumpy - I have been following that tecumseh thread, sure is a strange one.

The mower was tested for spark with no filter when I first fired it up.

If I replace even the cover without the filter the engine runs so rough its not funny, take the filter and cover of and its all fine.

Smoke comes out the breather which made me think it might be full of oil. I might be wrong though. The mower now has the correct amount of oil in it.

Hope that makes sense

That is all clear, Peter, but what is wrong is less so. First, if you run it without the filter and cover, does the spark plug stay healthy (dry, and more grey than black)? If so, the small intake restriction from the filter and housing may be affecting the carburetion, perhaps by blocking the air bleed. However I proposed a similar analysis in Paul's chonda thread when he reported the same symptom - the problem was that the presence or absence of the air filter actually had nothing to do with the symptom in that case, the real problem was that the ride-on mower was applying voltage to his kill wire and causing an ignition malfunction, all else was coincidence.

So, I'm proposing that you do a couple of with-and-without tests to get the situation clear at the beginning. I'd like to eliminate any possibility of coincidence causing symptoms, rather than whatever change you were attempting to test.

1) The mower was running fine lower than expected revs with no air filter after doing more careful analysis
2) I applied the air filter and it would cough and splutter, then eventually stall.
After some thinking I went back to the linkages and noticed the idle and full speed adjustment screws were way out of whack (the linkage set was a bit mangled), compared to my original experiences with tuning these engines.
With the engine going ( after replacing the linkages and with no air filter) I adjusted the screws until I got a sweeter sound and eventually got the air filter installed with the engine running. Once I kept the engine going with the air filter on their was still a little coughing and spluttering from the excess oil however after 15 minutes of good mowing in the long grass at the back of my suburb the smoke cleared and the mower was running really smooth.
So in short, I need to pay a little more attention to the carby linkages to find that right set point in future. I should have noticed in the beginning the linkage and tuning screws where way out of whack and bent. A simple switch from a good engine sorted it all out.
So:
Replaced the float and needle seat which stopped the flooding (float was full of fuel) and someone had a bit of small hose for a needle seat
Replaced the mangled linkages off a blown up engine off my spare parts pile
Change of oil and blades
Now this mower is a damm good runner and good for another few years, all for less than $30.
Thanks Grumpy, appreciate your help as always.

You fixed it Peter, I didn't, so there is no occasion for thanks. Your investigation reminds us once again to sort out the bent and broken pieces of our engines before we expect them to run properly. Incidentally I'm not comfortable with that "bit of small hose for a needle seat" - that seat needs to be made out of brass or Viton, not hose, or you probably won't get a season out of it. Do you have a better carburetor body, complete with seat, on your spares engine?

Grumpy, I should have been clearer, I used a brand new needle seat from a new carby kit. The hose piece I found was from the previous tenant. I laughed when seeing it!

If I cant fix it properly it doesnt get moved onto a new home until I can fix it properly. Thats just my rule. No half jobs.

I'm glad to hear that Peter - that is what I thought you did. If I didn't think that I'd have been hassling you about it months ago. I always think I know who does the work properly and who doesn't, and I had you on the good side of the ledger.

I'll close this thread.