Jump to content

Unofficial Home of Old Simplicity & Allis-Chalmers Garden Tractors

Sign in to follow this  
osenga

16hp Briggs starting problem

Recommended Posts

osenga

Just rebuilt a 16hp Briggs (326431) and all put back into timing and all new gaskets. And got really hot spark to. This has good compression. So here is what problems I have when the plug is out it cranks over great. When I put the plug in it don't want to crank over. I am lost now. I have tried 8 different S/G same thing on all of the 3 different battery's one was my trucks while i had (truck) running and nothing. I have made up a wiring harness to use a push start on it and also have just used jumper cables. All the same results. If anybody has any ideas to get this running this will be great.

Share this post


Link to post
Share on other sites
superbman101

Crank over as in won't go through a stroke? Or crack over as in spark when threaded in?If its the 1st: Milo might be right? someone may have messed up the depth? I doubt it though2nd: To spark when threaded into the hole it needs to be grounded, maybe the threads are so covered and head bolts that your not getting a good ground from block through head to plug?Ronald is dead on too! I have overtightened belts and it pulls the mag out just enough to mess up the ignition. Re-Gap mag accordingly. Better little loose on the belt (they are way cheaper than bearings :P )

quote:Originally posted by bigten65

spark plug hitting the top of the piston?


id="quote">
id="quote">

Share this post


Link to post
Share on other sites
osenga

Well I say good compression because on the up stroke of it. It does get stiff to turn flywheel by hand can't check it because if plug hole is plugged it won't turn over with a battery and rope start it wants to take my arm off. And piston not hitting the plug .

Share this post


Link to post
Share on other sites
JimDk

Too much clearance on the intake valve. Should be .008 for the de-compression bump on the cam to work. Just a guess on my part, but

if it is rolling over with the plug out there should not be any other mechanical problem.

Share this post


Link to post
Share on other sites
HubbardRA

Jim, you and I had the same idea. You just beat me to it. Valve clearances are something that get totally overlooked quite often. Too loose must be from a rebuild. The valves usually get tighter from wear.

Share this post


Link to post
Share on other sites
GLPointon

Bryan it DOES sound like valve timing to me too... or just a weak battery. put a volt meter on the battery or starter solinoid while cranking (or trying to crank) and see if the voltage drops way below 12...if good it shouldn't have a big voltage drop....otherwise...valve issue is my guess

Good luck!

Share this post


Link to post
Share on other sites
GLPointon

Do the voltage drop test at the starter terminal for + lead on your meter and on the battery for - lead.

If it drops while trying to crank it then there IS a problem in the starter curcuit. If no drop then you can rule out any electrical trbl on the starter circuit. My guess is you'll get a drop. Do you have a solinoid or starter button? cruddy contacts or wire anywhere in the curcuit can cause a voltage drop.

A healthy circuit will stay around 10-12v while cranking.

sm01

Share this post


Link to post
Share on other sites
perry
quote:Originally posted by osenga

Well for the battery I can't see it being weak it starts my truck every day and had the truck running. And it was a S/G . And my crank (/) mark lines up to the (•)


id="quote">
id="quote">well that sucks bryan about the engine. did you bypass everything and try jumper cables directly to the S&G post ? . if you did not touch valves or cam then i cant see it being anything internal . do you have trans fluid in the cylinder to lubricate/set the new rings ?.

Share this post


Link to post
Share on other sites
MrSteele

"It does get stiff to turn flywheel by hand can't check it because if plug hole is plugged it won't turn over with a battery and rope start it wants to take my arm off.

Is it attempting to backfire when you use a rope? If you had the mag off while it was apart, you might not have put it where it is supposed to be, and though everything else seems right, you are still out of time. The holes in the mag are slotted and oversize. If the points don't trip to fire at TDC, you get the backfire that will pull your arm out of joint

Share this post


Link to post
Share on other sites
GLPointon

I think he is in a cranking problem now not an ignition issue, it wont crank over at all using the starter with the plug in (w/compression pressure) so if not electrical then its mechanical, like valves again. Perry had a good point about new rings draggin? trans fluid in cyl? cant wait to hear more,,,good luck Bryan

quote:Originally posted by MrSteele

"It does get stiff to turn flywheel by hand can't check it because if plug hole is plugged it won't turn over with a battery and rope start it wants to take my arm off.Is it attempting to backfire when you use a rope? If you had the mag off while it was apart, you might not have put it where it is supposed to be, and though everything else seems right, you are still out of time. The holes in the mag are slotted and oversize. If the points don't trip to fire at TDC, you get the backfire that will pull your arm out of joint


id="quote">
id="quote">

Share this post


Link to post
Share on other sites
sliderxc

I think he has a different problem he said it gets stiff when turning over by hand I wonder if he left the groove in the top of the cylinder and the new piston and rings are having to compress to get over the groove

Share this post


Link to post
Share on other sites
osenga

Bob can't do a compression test that I have to plug off the hole. While plug is out it cranks fine with S/G and soon as I put even my thump over hole it stops cranking. And no groove in the cylinder walls for rings to get over

Share this post


Link to post
Share on other sites
Tonyvdb

Seems like everyone has an opinion on this one, so I'll throw in mine. If just putting your thumb over the spark plug hole will make it so it won't turn over, then it's not a timing problem, my guess is the starter generator. As they say in the dealer shops, replace with a known good unit. If you are jumping it with your truck, could be bad jumper cables or connection, but I assume you have already looked at that.

Keep us informed on progress, you got my curiosity up now.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

Sign in to follow this  

  • Who's Online (See full list)

    • PhanDad
    • RAC
    • marksr
    • rbstuartjr
    • littlemarv
    • simplewrench
  • Today's Birthdays

    1. thmsdoyle
      thmsdoyle
      (60 years old)
  • Recent Status Updates

    • F.U.N.

      F.U.N.  »  sandyhillbill

      Dear Sandhillbill
      Can you please copy me on this data, for Sun Star parts list.
      :
      September 12, 2004 Mike I sent you a PM and have all the mfgs. available for the tiller/hitch/pto/liftgroup if you need me to send them to you. Let me know. Thanks, F.U.N.    
      · 0 replies
    • gwiseman

      gwiseman

      Club banners are available  for members use during show season https://simpletractors.com/forums/topic/57849-simpletractors-club-banners-available/
       
      · 0 replies
  • Adverts

×