Register free!
Search
 
     

The Green Industry's Resource Center


Click for Weather
Reply
 
Thread Tools Display Modes
  #11  
Old 12-31-2012, 01:19 AM
fatboynormmie's Avatar
fatboynormmie fatboynormmie is offline
LawnSite Senior Member
 
Join Date: Jul 2009
Location: balto md
Posts: 731
Quote:
Originally Posted by Breezmister View Post
As long as that wire is not grounding out, even if you take it off from the coil, if the coil is good, it wouldn't stop it from giving spark.

One wire comes from the tab on the coil to the switch, the second wire come from the switch to a ground on the coil. When you turn the switch off, it grounds the coil.

I have had a wire (the one coming from the coil) where the covering was worn, and rubbed against the housing causing the coil to ground out.
Thats what I was getting at in my previous post.I too have had an intermittent no run caused by a chaffed compromised grounding wire.Thats why I suggested to completely unplug it from the coil and eliminate it from the equation . Could be bleeding off enough current in the spark to not allow it to fire under compression.Spark plug in open air you may see some spark there.
Reply With Quote
  #12  
Old 12-31-2012, 08:54 AM
piston slapper's Avatar
piston slapper piston slapper is offline
LawnSite Platinum Member
 
Join Date: Mar 2010
Location: Tampa Fl
Posts: 4,008
Quote:
Originally Posted by ed2hess View Post
This unit is almost 10 years old......I am going to get it running one way or another and for less than $20, not counting labor. It helps me understand how to fix stuff quick on new machines.


I guess I should bump this up to the stump the mechanic I think I now know what the problem may be and I missed the biggest clue that is shown in those first pictures. Anybody have an idea?
Determination separates the wannabe mechanics from the truly gifted...
Most think the job is easy just because you diagnosed and fixed a trimmer in 5 minutes..
They don't realize how many engines kicked your ass to make you so smart...
They also complain about paying a minimum charge when you make it look easy...
Pay Your Dues.....To The Victor Go The Spoils....

Thanx for the pictoral threads Ed....
Happy New Year.....Slapper
__________________
If You Have All The Answers...Except The One You Need...You're Not Trying Hard Enough...
Do The Work
Reply With Quote
  #13  
Old 12-31-2012, 09:42 AM
BigFish's Avatar
BigFish BigFish is offline
LawnSite Bronze Member
 
Join Date: Jul 2008
Location: chesapeake, va
Posts: 1,603
Quote:
Originally Posted by ed2hess View Post
I thought sure that the seal behind the flywheel was out but it was clean
and dry as could be. There was a little leakage on the other end of the crank behind the recoil but no gue like in the picture. I put a new seal behind the recoil. Yes I got a pressure tester rig that will be used next. So both crank seals are good and I verified that the cyclinder gasket was good when I pulled the cyclinder off twice.
The only thing left is a sheared flywheel key/crank keyway.
What caused the piston to bust up a skirt?
And how can you possibly work on anything that filthy????
__________________
" But let me tell you something ,folks: You can't fix stupid! There's not a pill you can take, there's not a class you can go to. Stupid is forever!"

......AMF!
Reply With Quote
  #14  
Old 12-31-2012, 09:49 AM
piston slapper's Avatar
piston slapper piston slapper is offline
LawnSite Platinum Member
 
Join Date: Mar 2010
Location: Tampa Fl
Posts: 4,008
Cracked or leaking isoblock....the only thing with a clean spot on the engine..
__________________
If You Have All The Answers...Except The One You Need...You're Not Trying Hard Enough...
Do The Work
Reply With Quote
  #15  
Old 12-31-2012, 10:03 AM
BigFish's Avatar
BigFish BigFish is offline
LawnSite Bronze Member
 
Join Date: Jul 2008
Location: chesapeake, va
Posts: 1,603
Quote:
Originally Posted by piston slapper View Post
Cracked or leaking isoblock....the only thing with a clean spot on the engine..
I'm assumin' he already checked that out, since he had the carb and cylinder off.

I could be wrong, but from readin' some of his other posts, it appears as though he re-uses gaskets, wrist-pin clips etc., so anythings possible!
__________________
" But let me tell you something ,folks: You can't fix stupid! There's not a pill you can take, there's not a class you can go to. Stupid is forever!"

......AMF!
Reply With Quote
  #16  
Old 12-31-2012, 10:29 AM
piston slapper's Avatar
piston slapper piston slapper is offline
LawnSite Platinum Member
 
Join Date: Mar 2010
Location: Tampa Fl
Posts: 4,008
I hear you Fish...
Could be a chinese sparkplug...I had one that would spark when laid against the cylinder...
But wouldn't hit a lick under compression...
__________________
If You Have All The Answers...Except The One You Need...You're Not Trying Hard Enough...
Do The Work
Reply With Quote
  #17  
Old 12-31-2012, 12:54 PM
Breezmister's Avatar
Breezmister Breezmister is offline
LawnSite Bronze Member
 
Join Date: Jul 2007
Location: South Jersey
Posts: 1,178
Quote:
Originally Posted by ed2hess View Post
. I did a compression test and it was 90.
You are just at the edge at 90 psi, anything less and I would do a complete rebuild or strip it for parts.

If you are leaking oil, it's got to be coming from a bad/leaking/warped cylinder base or a warped isoblock

A couple tricks you can try, double up on the cylinder gaskets, or get some high temperature gasket sealer and put some on both sides of the gasket (s)

If it is the isoblock, take some fine emery paper, on a flat smooth surface and sand it down untill you are flat on both sides. If the isoblock is warped, your first few passes will highlight the high points. You can also use the high temp gasket sealer here too.

Happy New Year
__________________
.
Masters Degree in Thinking Out Side Of The Box,Graduate of the MacGyver Institute of Ingenuity

The primary function of an Engineer is to make it difficult for the Fabricator and impossible for the Mechanic

RTFM What a concept

Reply With Quote
  #18  
Old 12-31-2012, 05:45 PM
ed2hess's Avatar
ed2hess ed2hess is offline
LawnSite Fanatic
 
Join Date: Nov 2002
Location: Austin Texas 78727
Posts: 11,350
In taking it apart to do the vac test I pulled the flywheel. To my surprise there was a lot of caked gunk back there, something I couldn't see when I peeped behind with the flywheel on.

Name:  060.jpg
Views: 66
Size:  64.5 KB
Name:  061.jpg
Views: 67
Size:  53.6 KB

I did the vac test and it was holding at about 45...don't know parameters...in. of mercury or something.
Name:  062.jpg
Views: 68
Size:  68.1 KB

Then I got the bright idea to do a pressure test. But instead of using my brake vac device I got the leak tester. So I sit pressure at 40 and though i felt a small leak so I went to 50.

Name:  064.jpg
Views: 67
Size:  67.3 KB
This got in before the picture of glasses
I decided to put on NEW gaskets and a NEW seal on flywheel side(other side already done) and give her a try. I checked the iso plate for flatness. But it was changed out anyway.

Name:  065.jpg
Views: 67
Size:  79.5 KB

Just as I was lowering my face toward the air leak the crankshaft seal blew out and hit my grasses

Name:  063.jpg
Views: 66
Size:  54.3 KB
Got to order seal....Happy New Year
Reply With Quote
  #19  
Old 01-03-2013, 05:50 PM
dboyd351 dboyd351 is online now
LawnSite Senior Member
 
Join Date: Sep 2010
Location: Cape Charles, VA
Posts: 825
Quote:
Originally Posted by Breezmister View Post
You are just at the edge at 90 psi, anything less and I would do a complete rebuild or strip it for parts.
I agree with Breezmister, 90 psi is borderline. Add anything else, like a weak/intermittent spark and it probably won't run. You may well have 2 problems interacting, with one of them being the compression.
Reply With Quote
  #20  
Old 01-04-2013, 07:46 PM
ed2hess's Avatar
ed2hess ed2hess is offline
LawnSite Fanatic
 
Join Date: Nov 2002
Location: Austin Texas 78727
Posts: 11,350
Quote:
Originally Posted by dboyd351 View Post
I agree with Breezmister, 90 psi is borderline. Add anything else, like a weak/intermittent spark and it probably won't run. You may well have 2 problems interacting, with one of them being the compression.
Coil replaced under warrant. I kinda have to agree but don't know where else to go. It passed vac test. The carb works on another unit that measured 90psi.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump





Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ©1998 - 2012, LawnSite.comô - Moose River Media
All times are GMT -4. The time now is 12:06 PM.

Page generated in 0.14810 seconds with 10 queries