I could really use some advice. I am working on a Briggs 18.5 ELS500 engine off of my daughters Husqvarna mower.
-Engine: 31Q777-0466-E1
-Motor RPM's raced suddenly and would not slow. I suspected a governor weight after eliminating all else external.
-Opened up engine and found broken compression relief off of camshaft, and a governor with what appears to be only ONE little plastic oil slinger ears broken off. That's it. It does not look as if governor has ANY other damage (but after getting a new one I will compare).
-QUESTIONS
-Will the engine race with what I have described, with only that ONE little part broke on governor?
-Will the broken compression release make it race?
-While cleaning crankcase and getting out metal fragments from compression release, I took out camshaft and I tipped up the motor and the valve tappets and push rods fell out. I was able to put all parts back in the correct intake and exhaust holes, but is there anything inside that I may have messed up when they fell out, or do they simply slide back in as it appears?
-I think the part number for the camshaft is 793880 , but I cannot find the part number for the new COMPLETE governor assembly. Any ideas on that part number?
-Lastly, has anyone had any luck with the aftermarket camshafts sold on Ebay? They are about 1/2 price, but are they unbranded junk?
(I plan on getting a whole new camshaft with compression release because it appears I cannot just repair the compression release, correct)?
I could really use some help with these questions!
Jeff
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#2
Scrubcadet10
cam part number is correct, if you order a new cam order 2 new tappets (690564) or at least thats what ive always done, since these two parts wear together.
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governor assembly is Part number (691968).
a broken compression release will not cause it to race, it releases compression when starting so you or the starter doesnt have to pull over 120+ pounds of air.
I plan on getting a whole new camshaft with compression release because it appears I cannot just repair the compression release, correct)?
it might be a good idea to go ahead and replace the oil seal in the crankcase cover while you can do it, dont have to, just my personal preference.
and pre lube the cam shaft and any metal contact surfaces with engine oil before reassembly
Can you help me understand how it could have affected my valve clearance? I mean, that is adjusted with a wrench, so if I did not adjust my valves how could it have affected my valve clearance?
Thanks for helping,
Jeff
#4
Scrubcadet10
I think i typed faster than my brain was going, dont worry about checking the clearance until you get it reassembled. so it's nothing to worry about.
but it will not hurt anything to check it once your done as it's part of regular "maintenance".
AFAIK the governor & oil slinger only come as a single assembly # 691968 - SLINGER, Governor/Oil according to my parts books.
There are after market cam shafts available through Rotary, Oregon etc, these are certified good & come with a warranty.
Or there is genuine B & S
Everything else is suspect, how many times have you won a lottery ? what is your luck like ?
If a part is good it will come in a branded package or be branded itself .
If I am selling stuff I bought as scrap metal on Amazon / Ebay as OEM replacement part, the last thing I would want is to be identified .
Considering the cost of a gasket set is about the same as the difference between the genuine & fake products . plus your time , plus oil plus plus plus, is it worth the risk ?
And
Yes the broken wing could throw the mechanism out of balance or could even have jambed the governor.
A new cam comes with followers so don't worry about them, they are identical
No they have not caused any damage falling out
Yes & No the broken compression release can jamb the governor but it's absence will not affect the engine other than make it impossible to start.
Good chance the compression release hit the slinger paddle & broke it off.
Make sure you polish the crankshaft , both ends before replacing it , fit new seals and cover the PTO with glad wrap to prevent it cutting the lower oil seal.
When you get the new cam, have a good look at the comp release & make sure all of the broken bits are accounted for it does not take a big bit of metal to jamb the gear teeth, nasty result.
Thanks for the replies! A couple things, how do I polish the camshaft, and do you know the valve settings? I have heard .oo5 on Intake and .009 on exhaust?
Jeff
