B & S - 17hp hard spot

If your motors are overhead valve check the valve settings they might need adjusting

I did check the valve settings, did all I can and even the factory could think of short of cracking open the case to get to the crank. Bigger question is why all 3 have the same problem?

Electricals Too!

Could be the condition of your battery or perhaps starter drag dropping your voltage. Maybe starter gear set, They make two different type one compatible with a metal flywheel ring gear and the other with a phenolic or fiber ring gear. I have also run into a problem with the starter gear having an outside diameter to large or incorrect pitch. I discovered this when I checked a starter gear with a new B&S OEM gear. The one on the starter may have been an after market or another manufacturer than B&S. Not only was the gear to large but it also was the wrong pitch and had an extra tooth. Lots of things to check good luck!

Make sure u check the valve setting at 1/4 past TDC, and set them at .004

Before you reply on this forum, do you even read the other post??? This has happened to three different motors with three good starters, three strong batteries and all three have the correct valve settings. That is the big question.

if u are talking about ME , just because someone sets the valves, we dont know that he set them just right, also these engines are known to wear the cams some and if u set the valves as close as u can ,say even .002 , it just might make a different,,,,, TOM

i have worked on 2 husky mowers that had the same identical problem and what i found was that the valves were loose especially if your exhaust valve is not opening it makes it work like an engine brake

I would think the starters need rebuilt but "This has happened to three different motors with three good starters," however, I am no starter motor expert, I would have it looked at by a reputable motor shop. Then I would check all the wiring associated with the starting system and look for corrosion. Two reasons for this advice are you said with the plug out it spins most times and you spin the engine by hand with no ill results. Try a new or rebuilt starter.

When you have eliminated the impossible, that which remains, however improbable, must be the truth.- Sir Arthur Conan Doyle - Sherlock Holmes.

I am having a similar problem that I thought was a bad battery or a bad charging system. It's also a B&S 16.5 HP (I think) motor that starts hard. My symptoms are just like a battery with not enough oooomph and a jump start makes all the difference in the world. Could I be experiencing something in my 6 year old tractor such as the OP's problem or should I really be looking at battery/charging problems. My battery was new a year ago last spring and really still had the same problem (hard start) from new. Thanks for any help that you can lend me.....

I would not look at a year old battery I would however look at a six year old starter motor with wore out brushes in it. Lets face it guys they no longer build these like they used to!!!! Cheap foreign components and all you know, but at least it is cheap to get them rebuilt.

I'll have to look into that soon..... it's a pain to have the thing not start!!

declid: you are so very right about the valves being the cause of the 'hard spot' in these motors. I did set them as you said, but it didn't work, guess I didn't do it right. Today, I tightened down on each rocker arm about 1/2 of turn saying what the heck, it doesn't run now so here goes, didn't have a feeler gauge with me. I did turn the engine by hand to make sure the valves didn't hit. Then I cranked it with the started with the plug in but not connected. It turned over fine. The next test with the plug connected - it started right up. Don't know what the valves are set at, but it starts and runs great. Thanks

David 686
I found this posting ever interesting as you are having the same problem that I attempted to address with my post of Feb.11 titled "Old yeller"... I will now be looking very hard at the valves as I know the starter and battery are good. Thanks for your post. You articulated the issue very well. Thanks to everyone else for your input.
Now please, someone who knows carburetors please help me with the John Deere/Nikki issue. See my post dated Feb.11. Thanks everyone.

valves

mrbeal said:

I am having a similar problem that I thought was a bad battery or a bad charging system. It's also a B&S 16.5 HP (I think) motor that starts hard. My symptoms are just like a battery with not enough oooomph and a jump start makes all the difference in the world. Could I be experiencing something in my 6 year old tractor such as the OP's problem or should I really be looking at battery/charging problems. My battery was new a year ago last spring and really still had the same problem (hard start) from new. Thanks for any help that you can lend me.....

Click to expand...

my 24hp b&s was hard to start when I bought it 5 years ago,last week it wouldnt hardly turn over.I took it to the shop and they said the valves were way out of adjustment

Hard spot update: On a recent visit to my local lawn mower shop for unrelated parts, I asked about the hard start/valve problem -- all the guys there just smiled and said "Yes, that is the problem and the B&S motors are very bad about this." I just wonder how much 'repair' money they have made with this little fix?

There is a compresson release on the cam and if the valves are set a little off it will interfear and do this same thing

When I took one of my motors apart to see what could have caused the 'hard spot' ploblem, I saw that thing and didn't know what it was for. The guys at the shop said that it is a compresson release and if the spring on it goes out, it can also cause the 'hard spot' starting problem. The parts list I have call the compresson release a "slinger-governor/oil". At 65 years old I try to learn some thing new every day and on that day, that was it.

david686 Im 63 and everyday not learning something is a waist for me I have a small shop and just try to do it part time but you know how that go's I really dont want to hire help so only pick and choose , but can say no to any senior lol ED