d124716 7 #1 Posted April 12, 2023 Hello and thank you for looking at my post. I have a toro 13-38xl (13HP, B&S model# 28M707 Type 1122-E1) that I had for many years. Some time ago it started having issues starting and smoking heavy on start up. Once the tractor warms up for a bit it works great, restarts easy, no issues when warm. I've cleaned the carb, put a new plug, new air filter, new breather on it, cylinder compression checked at at 70psi . It didn't solve the problem, tractor worked for a season but progressively got worst. I went to start it up just now and it would run for a few seconds and then die out. I've noticed that there is a lot of oil in the air intake "sum" that connects to the breather hose (see picture below). Tried running the tractor without the filter, it starts runs great for a few seconds and then the oil fountains out of the air cleaner "sump" as the motor dies. I took off the rubber breather hose (see picture below) and started the engine, again ran great for a few seconds and then the oil flooded out of the rubber hose like a fountain. I am guessing but it feels like the oil is being passed back into the air intake and then chokes the motor out. There is a "charring" black residue all over the front of the tracker where the exhaust comes out. I love this thing, it served me well for many years and would hate to let it go. Please help.... Thank you! 1 Share this post Link to post Share on other sites
RED-Z06 2,567 #2 Posted April 12, 2023 Oil is contaminated with gas most likely...carb probably needs a new needle and seat. 1 Share this post Link to post Share on other sites
Achto 29,386 #3 Posted April 12, 2023 9 hours ago, d124716 said: Some time ago it started having issues starting and smoking heavy on start up Is your oil level over full? If so you may be leaking gas into the crank case. Float not shutting the gas off inside of the carburetor. 70lbs of compression sounds a little low. You may have blow by on the piston rings causing excess crank case pressure. This would force oil out the breather. 2 Share this post Link to post Share on other sites
d124716 7 #4 Posted April 12, 2023 Thank you for commenting, few follow up notes and a question. 1. Dip stick does smell like gas. 2. When "oil" shoots out of the breather it does feel / look to be much thinner than it should be. 3. On initial start up the starter has a hard time turning the engine over, almost like a hydro lock indeed. However, after a few seconds / tries the starter spins the motor with good RPMs (I've always blamed this on a weak battery). 4. On initial start up the motor does take a very long time to start, it will spin and spin for 5-8 tries with about average of 5 seconds for starter engagement. 5. Oil level on dips stick is very high... almost unbelievably high. I've always checked the oil after the engine had a chance to distribute the oil all over itself, when doing it that way the level seemed to be in order. Follow up questions: What tests are there to determine if I have a leaky carb issue or a worn piston rings issue? Thank you! 2 Share this post Link to post Share on other sites
Ed Kennell 41,845 #5 Posted April 12, 2023 Gas in the crankcase is dangerous to you and the engine. The gas is likely entering the crankase either thru the carb or thru a fuel pump. The carb float may be full of fuel and no longer floating or the needle shut off valve may not be sealing. The fuel pump may be leaking fuel thru a bad diaphram into the crankase. 1 Share this post Link to post Share on other sites
Blasterdad 3,044 #6 Posted April 12, 2023 How rude of us, no one has said yet! Did you take the carb apart to clean it? Have you taken the fuel pump off yet? Share this post Link to post Share on other sites
d124716 7 #7 Posted April 12, 2023 6 minutes ago, Blasterdad said: How rude of us, no one has said yet! Did you take the carb apart to clean it? Have you taken the fuel pump off yet? Hi Blasterdad, thank you! I have taken the carb out to clean it out a few times now. I do not think there is a fuel pump on this model. 1 Share this post Link to post Share on other sites
Blasterdad 3,044 #8 Posted April 12, 2023 1 minute ago, d124716 said: I do not think there is a fuel pump on this model. Even better. Did you actually take the carb apart, if so did you replace the gaskets? Share this post Link to post Share on other sites
d124716 7 #9 Posted April 12, 2023 33 minutes ago, Blasterdad said: Even better. Did you actually take the carb apart, if so did you replace the gaskets? No sir, just cleaned everything out...all though it all looked clean anyway ... I was hoping the issue was with something being clogged but it wasn't... so I put everything back together as it was and rolled around for another season.. I've been doing that every season or so but the last season the machine was acting really bad and now with the winter gone I went to start it and I know I will be fighting the same issues except I can tell they are progressively getting worse. 1 Share this post Link to post Share on other sites
Blasterdad 3,044 #10 Posted April 12, 2023 You're going to have to get a rebuild kit for it & do it right, not that expensive & easy to do. It will have all the gaskets & new float needle & seat. 1 Share this post Link to post Share on other sites
d124716 7 #11 Posted April 12, 2023 16 minutes ago, Blasterdad said: You're going to have to get a rebuild kit for it & do it right, not that expensive & easy to do. It will have all the gaskets & new float needle & seat. got it. Just bought a whole new carburator $16 on Amazon, we'll see how it works out! 1 Share this post Link to post Share on other sites
RED-Z06 2,567 #12 Posted April 12, 2023 Cant tell much by compression on these, the compression release limits cranking compression to 50-75psi usually, depending on valve lash. Dont toss your old carb in case the replacement has issues you can still rebuild the original Share this post Link to post Share on other sites
d124716 7 #13 Posted April 12, 2023 17 minutes ago, RED-Z06 said: Cant tell much by compression on these, the compression release limits cranking compression to 50-75psi usually, depending on valve lash. Dont toss your old carb in case the replacement has issues you can still rebuild the original is there anything like a leak down test or something of that sort that can be done to test for blow by? 1 Share this post Link to post Share on other sites
d124716 7 #14 Posted April 14, 2023 drained the "oil"... it looked like it had a viscosity of water. Put new oil in, put a new carburetor in. Started well, ran great, smoked out whatever it had in the muffler and then the exhaust pipe looked dry for the rest of the test run. Three follow up questions: 1. While in idle I removed the dip stick and the motor died - is that normal? If I put the throttle about 1/2 way up and remove the dip stick the motor wouldn't die but I would get spatter of oil coming out of the filler tube - is all of that normal? 2. What is the procedure for air screw adjustment? Since I put a new carburetor on the screw was left however it came out of the box. The motor ran good but I am just wondering perhaps I can tune it in better. 3. Does this motor have valve seals? I kept looking online for something similar to a car engine for a valve steam seal and couldn't find it on a diagram anywhere. Thank you! Share this post Link to post Share on other sites
RED-Z06 2,567 #15 Posted April 14, 2023 4 minutes ago, d124716 said: drained the "oil"... it looked like it had a viscosity of water. Put new oil in, put a new carburetor in. Started well, ran great, smoked out whatever it had in the muffler and then the exhaust pipe looked dry for the rest of the test run. Three follow up questions: 1. While in idle I removed the dip stick and the motor died - is that normal? If I put the throttle about 1/2 way up and remove the dip stick the motor wouldn't die but I would get spatter of oil coming out of the filler tube - is all of that normal? 2. What is the procedure for air screw adjustment? Since I put a new carburetor on the screw was left however it came out of the box. The motor ran good but I am just wondering perhaps I can tune it in better. 3. Does this motor have valve seals? I kept looking online for something similar to a car engine for a valve steam seal and couldn't find it on a diagram anywhere. Thank you! Dont pull the dipstick while its running, no reason to, oil is vaporized and there's always blow by...if you have a fuel pump it will make the fuel pump stop pumping. Air screw usually does little to the tuning, if its idling nicely..i wouldn't mess with it, they were usually pretty fragile screws. I dont know your exact model and spec numbers but briggs usually put a seal on the intake valve of their ohv engines. If you still have the 28M707, it was a flathead engine and didnt have any seals. Share this post Link to post Share on other sites