Rieju & GasGas Legacy Riders Club Forum  

Go Back   Rieju & GasGas Legacy Riders Club Forum > GasGas Enduro Technical Forums > Enduro Engine - 2 stroke

Enduro Engine - 2 stroke Cylinder, Piston, Tranny, Bearings, Clutch, Pipes & Silencers, etc.


Reply
 
Thread Tools Display Modes
  #1  
Old 10-23-2020, 03:48 PM
scrambler250 scrambler250 is offline
Member
 
Join Date: Sep 2007
Location: East TN
Posts: 14
Default Help diagnose engine seizure

I was on a dual sport/adventure ride a few weekends ago and seized my engine. I was about 20 miles in, all gravel/dirt roads, topped a hill, and the engine shut down. I hadn't gotten to full throttle over that 20 miles, and wasn't pushing the engine particularly hard when it died. I had mixed Stihl Ultra (synthetic) 50:1 the night before with 87 oct. I usually use Bel-Ray H1R, but have run the Stihl mix recently with no issues. The plug looked good, maybe a little rich. The piston/cylinder had a four corner seizure. The worst scaring was on the intake/clutch side, and exhaust/flywheel side. Those corners both had a piece of cylinder plating stuck to the piston. I've only put ~15 hours on this piston & cylinder since replating. Is this seizure from a flaw in the plating process or just a lack of lubrication? I quit racing enduros years ago, and was hoping to transition this bike into some dual sport use, but is this type of riding (relatively consistent speeds over longer distances) more than what I should expect to be able to reliably do? Also, any suggestions on where to get this cylinder replated?
Attached Images
File Type: jpg IMG_2367.jpg (111.7 KB, 61 views)
File Type: jpg IMG_2368.jpg (120.4 KB, 52 views)
File Type: jpg IMG_2370.jpg (118.6 KB, 51 views)
File Type: jpg IMG_2371.jpg (112.8 KB, 44 views)


__________________
'01 xc 250
'07 ec 300 w/2k2
Reply With Quote


  #2  
Old 10-23-2020, 06:19 PM
blitz11's Avatar
blitz11 blitz11 is offline
Silver Level Site Supporter
 
Join Date: Oct 2006
Location: SW Montana
Posts: 702
Default

Water pump failure? Impeller failure (stock are generally a polymer)? Low/no coolant levels? Extended period of hot resulting in insufficient piston/cylinder clearance and subsequent wear?

Could be bad plating. Images don't show up too large on my 'puter.

Doesn't look like lean seize. Looks like it had been wearing for quite a while (armchair view).
Reply With Quote
  #3  
Old 10-23-2020, 08:24 PM
scrambler250 scrambler250 is offline
Member
 
Join Date: Sep 2007
Location: East TN
Posts: 14
Default

Water pump seems fine. Radiators were full, impeller looks fine. I didn't touch the cylinder for a few minutes after it locked up, but when I did, it wasn't hot.
__________________
'01 xc 250
'07 ec 300 w/2k2
Reply With Quote
  #4  
Old 10-24-2020, 03:46 AM
SS109's Avatar
SS109 SS109 is offline
Senior Member
 
Join Date: Jan 2011
Location: Tucson, AZ
Posts: 987
Default

Just curious, what does the top of the piston look like? Pic?
__________________
WildAzzRacing YouTube channel
Trail Riders of Southern AZ club
AZ State Parks OHV Ambassador
'11 EC250R
'98 KDX220
Reply With Quote
  #5  
Old 10-24-2020, 06:48 AM
Gasser Nate's Avatar
Gasser Nate Gasser Nate is offline
Senior Member
 
Join Date: May 2010
Posts: 644
Default

That plating does not look good at all, it looks like it has delaminated.
__________________
Back on a gassy! 2018 EC300! 🤘
Txt 280 07 to make me feel like a gumby again
Reply With Quote
  #6  
Old 10-24-2020, 08:26 AM
hamilton's Avatar
hamilton hamilton is offline
Gold Level Site Supporter
 
Join Date: Nov 2012
Location: Elkton Md
Posts: 452
Default

I don't see any crosshatch in the cylinder, was it honed to correct size after plating? Piston skirt ribs are also worn off was the piston clearance checked?

Anyhow these guys can fix you up.

http://www.powersealusa.com/
__________________
15 GASGAS EC 250
19 Sherco SE 125R
Reply With Quote
  #7  
Old 10-24-2020, 07:45 PM
scrambler250 scrambler250 is offline
Member
 
Join Date: Sep 2007
Location: East TN
Posts: 14
Default

Top of piston picture is attached. It's been a couple years since I had this cylinder replated. I don't remember who did the work, I'm trying to go back over records. I sent a new piston in with the cylinder and cylinder was supposed to be plated to match the piston. I don't think I checked piston clearance or ring gap after getting it back.
Attached Images
File Type: jpg IMG_7842.jpg (88.2 KB, 24 views)
__________________
'01 xc 250
'07 ec 300 w/2k2
Reply With Quote
  #8  
Old 10-24-2020, 11:24 PM
(F5)'s Avatar
(F5) (F5) is offline
Gold Level Site Supporter
 
Join Date: Jul 2006
Location: Wellington New Zealand
Posts: 2,063
Default

That doesn't show any detonation. Heck its clean as. Like no time on it really.

Ring end gap would be interesting.

4 corner can happen with too tight bore or thrashed when cold.

I'd be sending it to a reputable plater and check ring end gap when you have it back.

So. . Is stihl like a chainsaw oil? I'd be going back to belray or similar.
__________________
'07 EC300 GG
'14 TXT250 GG
'? 496 CPI Cheetah RZ/RGV hybrid
'22 765 Street Triple RS
'21 XTrainer
'69 Stinger T125 Suzuki
'23 TRS 250RR (it's a Trials thing)
Reply With Quote
  #9  
Old 10-27-2020, 04:32 PM
swazi_matt swazi_matt is offline
Senior Member
 
Join Date: May 2010
Location: From Swaziland, Now Hamilton New Zealand the “look but don’t touch” enduro heaven
Posts: 2,334
Default

looks like bits have come off the cylinder and jamed in there
__________________
2003 txt250 Pro
2013 Ossa 280i
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


Similar Threads
Thread Thread Starter Forum Replies Last Post
ec 125 engine help guyr Enduro Engine - 2 stroke 3 04-11-2016 02:42 PM
Need help to diagnose engine trouble... 95jersey Enduro Engine - 2 stroke 17 06-16-2015 07:50 AM
2014 200 Engine / 2011 200 Engine are they the same ? Dirt Dud General Discussions & Announcements 3 11-22-2014 08:18 AM
New Engine cladoo Enduro Engine - 2 stroke 8 10-07-2014 11:20 AM




All times are GMT -5. The time now is 07:05 AM.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright 2009 - GasGasRider.org