warreng5995
Member
- Joined
- Jan 26, 2021
- Threads
- 1
- Messages
- 22
Ok, a bit of an update.
I looked at the vacuum line today and about 1.5 to 2 inches of it was filled with oil (see first photo attached). ILENGINE & Born2Mow both of you said oil in the line may be normal. So I figured ok, lets not drain the line and leave the oil there and try to start it and see what happens. With the choke on, cranked it over and it fired right up.
So, I figured I might as well as pull the dipstick and see how much pressure it was pushing. Pulled the dipstick, and a light spray of oil did come out until I put my hand and paper towel over it. I could feel some air but didn't seem more than what I thought would be normal. After holding the paper towel over it for 5 or 10 seconds, I removed it and replaced the dip stick. There was some oil spray on the towel, but not soaked or anything. Oil level has stayed at the full mark this whole time.
Just for a comparison, I went out back to my other mower with B&S (16.5hp) and did the same thing. it actually sprayed more oil into my paper towel than this one did. But I am pretty sure it doesn't have a oil pump (but is "splash lube" only - I could be wrong about this though) as it doesn't have an oil filter like this engine does.
Back to this Vanguard, I ran the engine and let it come up to full temp, I watched the head and some other points with a infrared "laser" thermometer to see if I could find any abnormal hot spots. The hottest point on the head was near the spark plug, with temps around 280 to 300 f. The hottest spot I could find on the muffler was 680F at one point. Most of the muffler was around 450 to 500 f. Oil filter stayed between 122 and 130 f, as did the crankcase next to the filter. Valve cover got up to about 135 f. Other parts of the head and case were much cooler due to the air flow from the flywheel "cooling fan". I think the float bowl on the carb was around 110 f.
I will add there is no odd sounds or anything. It doesn't surge or etc. Runs smoothly.
Now that it was at full temp, I pulled the dipstick again and the air and oil spray seemed exactly the same as when I first started it. So no difference there.
Finally I turned off engine... let it sit for about 2 minuets or so. Tried to restart, it didn't want to, it chugged a bit, I let off the key and it chugged a few more times on its own but then picked back up to normal engine speed. So I ran it a few more minutes, and turned it off again. This time i let is sit about 5 minutes. Tried to restart, Nothing. Didn't even try to hit. Tried to restart it a few more times, letting it sit a minute or two between attempts, but never hit. Same as it did the other day.
I didn't have any more time to mess with it today, so that's all I was able to test.
But in short, it appears that the oil in the vacuum line isn't the issue, as it was that way today when I started the engine cold, and it fired right up just fine. So I guess that part is "solved" and appears to be a non-issue.
At this point, I don't think I'm getting piston blow by or bypass on the head gasket. As cold and hot both seemed to be the same with my mediocre "dip stick test".
I can't do a proper compression test on this engine, because it has the compression release on the cam shaft so it is easier to start. Which this compression release "lobe" doesn't move out of the way until the engine is running and the centrifugal force moves it. So from what I can see and understand, due to this compression release the compression PSI will never show correctly when just cranking the engine over. If anyone can confirm or refute this, please feel free to post such.
With that said, I did check my service manual StarTech and it listed 220 in-lbs as you said the old versions did. So when I have the time to pull the covers, intake/carb and etc. I may up the torque on the head to 250 in-lbs as per your suggestion.
So in the end with what little I was able to "test" today.... Why does the engine start cold just fine and seems to run "normally" and smoothly... but once hot when you shut it down for a few min, it won't restart?? Could this still be an issue with compression? Vapor lock in carb, but only after the engine cools?? Or...??? ?
Thanks All
I looked at the vacuum line today and about 1.5 to 2 inches of it was filled with oil (see first photo attached). ILENGINE & Born2Mow both of you said oil in the line may be normal. So I figured ok, lets not drain the line and leave the oil there and try to start it and see what happens. With the choke on, cranked it over and it fired right up.
So, I figured I might as well as pull the dipstick and see how much pressure it was pushing. Pulled the dipstick, and a light spray of oil did come out until I put my hand and paper towel over it. I could feel some air but didn't seem more than what I thought would be normal. After holding the paper towel over it for 5 or 10 seconds, I removed it and replaced the dip stick. There was some oil spray on the towel, but not soaked or anything. Oil level has stayed at the full mark this whole time.
Just for a comparison, I went out back to my other mower with B&S (16.5hp) and did the same thing. it actually sprayed more oil into my paper towel than this one did. But I am pretty sure it doesn't have a oil pump (but is "splash lube" only - I could be wrong about this though) as it doesn't have an oil filter like this engine does.
Back to this Vanguard, I ran the engine and let it come up to full temp, I watched the head and some other points with a infrared "laser" thermometer to see if I could find any abnormal hot spots. The hottest point on the head was near the spark plug, with temps around 280 to 300 f. The hottest spot I could find on the muffler was 680F at one point. Most of the muffler was around 450 to 500 f. Oil filter stayed between 122 and 130 f, as did the crankcase next to the filter. Valve cover got up to about 135 f. Other parts of the head and case were much cooler due to the air flow from the flywheel "cooling fan". I think the float bowl on the carb was around 110 f.
I will add there is no odd sounds or anything. It doesn't surge or etc. Runs smoothly.
Now that it was at full temp, I pulled the dipstick again and the air and oil spray seemed exactly the same as when I first started it. So no difference there.
Finally I turned off engine... let it sit for about 2 minuets or so. Tried to restart, it didn't want to, it chugged a bit, I let off the key and it chugged a few more times on its own but then picked back up to normal engine speed. So I ran it a few more minutes, and turned it off again. This time i let is sit about 5 minutes. Tried to restart, Nothing. Didn't even try to hit. Tried to restart it a few more times, letting it sit a minute or two between attempts, but never hit. Same as it did the other day.
I didn't have any more time to mess with it today, so that's all I was able to test.
But in short, it appears that the oil in the vacuum line isn't the issue, as it was that way today when I started the engine cold, and it fired right up just fine. So I guess that part is "solved" and appears to be a non-issue.
At this point, I don't think I'm getting piston blow by or bypass on the head gasket. As cold and hot both seemed to be the same with my mediocre "dip stick test".
I can't do a proper compression test on this engine, because it has the compression release on the cam shaft so it is easier to start. Which this compression release "lobe" doesn't move out of the way until the engine is running and the centrifugal force moves it. So from what I can see and understand, due to this compression release the compression PSI will never show correctly when just cranking the engine over. If anyone can confirm or refute this, please feel free to post such.
With that said, I did check my service manual StarTech and it listed 220 in-lbs as you said the old versions did. So when I have the time to pull the covers, intake/carb and etc. I may up the torque on the head to 250 in-lbs as per your suggestion.
So in the end with what little I was able to "test" today.... Why does the engine start cold just fine and seems to run "normally" and smoothly... but once hot when you shut it down for a few min, it won't restart?? Could this still be an issue with compression? Vapor lock in carb, but only after the engine cools?? Or...??? ?
Thanks All