Results 1 to 9 of 9

Thread: Metal in oil and engine locked up

  1. #1
    KTMTalk Member
    Join Date
    Jan 2010
    Location
    brisbane
    Posts
    512
    Images
    120

    Default Metal in oil and engine locked up

    Hi guys
    My low hour 98 620 is giving me some trouble, I pulled it down for a rebuild and gave it a new prox piston, re plate cylinder, and had the head ported while I was in there, it's run for about 4 rides of 45min on the road. Last ride on warm up the engine locked up in top gear cruising at low rpm. It started up again after a few kicks and seemed fine after that until 20min later then locked up again when my mate was riding. Started again and rode home no trouble.

    I noticed a lot of metal in the oil filter prior to the rebuild and now there's is more that I would expect normal after 2-3 hours new filter.

    I'm thinking something may be floating around in the gear box
    Or maybe clutch bearing failure?
    I just pulled the plates out and there's a small amount of movement in the outer basket but not excessive.

    Was there some clutch problem with these early LC4 engines?
    I remember hearing something but can't recall.
    The metal in the oil seems mostly non magnetic. I don't really want to split the cases but it's looking like I may need to.

    Anyone had tranny issues? Or any thing like this?
    Regards Cris
    Current bikes
    16 ktm 380 custom build http://ktmtalk.com/showthread.php?543034-2016-ktm-380
    06 ktm 380 custom build http://ktmtalk.com/showthread.php?54...ld-restoration
    04 Ktm 525
    98 ktm 620

    Previous bikes
    09 Ktm 300
    2000 fe 600 x2
    02 ktm 520(540cc)
    95 Ktm 620
    90 xr 630
    90 tt250
    91 kx 250
    83 yz 125

  2.    Sponsored Links




  3. #2

    Default Re: Metal in oil and engine locked up

    As the wheel locks up, if you pull in the clutch does it roll? if it does, I think its the engine side locking up.

    clutch basket wobble should be 1mm max, if you have like 4 or 5 mm there's an issue with that main shaft bearing, but Ive had mainshaft bearing failure(not bearing seizure), but it didn't cause lock up.

  4. #3
    KTMTalk Member
    Join Date
    Aug 2002
    Location
    Austin
    Posts
    793
    Images
    16

    Default Re: Metal in oil and engine locked up

    PROX piston expands at a higher rate than the OEM piston, therefore more piston to cylinder clearance is required with the PROX piston vs OEM. When the cylinder was replated, was clearance set for the PROX piston? Did you measure and set piston ring gaps?

  5. #4
    KTMTalk Member
    Join Date
    Jan 2010
    Location
    brisbane
    Posts
    512
    Images
    120

    Default Re: Metal in oil and engine locked up

    Very good points thanks guys
    As the lock up occurred I pulled the clutch and rolled to a stop, surprised by this i turned around to see a 5 metre black Mark on the bitumen, once stationary I clicked from 5th to neutral carefully applied pressure to the kick started and felt normal resistance. Took 5 or 6 kicks to start, went off carfullly.

    So this indicates the engine? As the tranny kept rolling with the clutch In

    I measured the ring gap it was on the loose side but the piston clearance was on the tight side at 0.05mm should be 0.06mm also didn't seem vertically consistent, tighter at the bottom i had a hell of a time getting the rings in.

    What concerns me is if it's the piston seizing up this doesn't explain all the metal in the oil filter prior to the rebuild.
    Is it the clutch basket bearing that fails or the bearing on the shaft behind that?
    Current bikes
    16 ktm 380 custom build http://ktmtalk.com/showthread.php?543034-2016-ktm-380
    06 ktm 380 custom build http://ktmtalk.com/showthread.php?54...ld-restoration
    04 Ktm 525
    98 ktm 620

    Previous bikes
    09 Ktm 300
    2000 fe 600 x2
    02 ktm 520(540cc)
    95 Ktm 620
    90 xr 630
    90 tt250
    91 kx 250
    83 yz 125

  6. #5
    KTMTalk Member BERG650's Avatar
    Join Date
    Mar 2005
    Location
    Sunset Desert
    Posts
    1,520
    Images
    1

    Default Re: Metal in oil and engine locked up

    There used to be a big thread on here about this failure on the LC4 engines....the bearing that was failing was the one on main (clutch ) shaft in the engine cases behind the clutch basket.

    Not sure its your problem though ?
    2018 500 EXC-F Aussie/Euro Version
    Sooooo glad Euro map is standard...


    2013 300 EXC
    .46s with KTMLew's stacks, PDS 6 on Terrys needled and bladdered shock, Flexx bars with Scotts damper.
    To Finke and Back x 3


    04 300 EXC. MSC damper and 16 mm clamps
    .48s and PDS 7.
    13/49 and the "yellow spring"


    03 FE 650 Husaberg.
    02 FE 501 Husaberg.

  7. #6
    KTMTalk Member
    Join Date
    Jan 2010
    Location
    brisbane
    Posts
    512
    Images
    120

    Default Re: Metal in oil and engine locked up

    Thanks berg

    There's no play in the main shaft however I may pull that bearing out and replace it since it's apart.

    I'll pull the head off and check the bore, pretty confident it's one of my problems

    Cheers
    Current bikes
    16 ktm 380 custom build http://ktmtalk.com/showthread.php?543034-2016-ktm-380
    06 ktm 380 custom build http://ktmtalk.com/showthread.php?54...ld-restoration
    04 Ktm 525
    98 ktm 620

    Previous bikes
    09 Ktm 300
    2000 fe 600 x2
    02 ktm 520(540cc)
    95 Ktm 620
    90 xr 630
    90 tt250
    91 kx 250
    83 yz 125

  8. #7

    Default Re: Metal in oil and engine locked up

    Im not positive, but if the engine did momentarily seize, I think it might strip the teeth on the oil pump idler gear.

    That might be the original issue is intermittent oiling , but as far as the tranny main shaft bearing, what fails is the ball bearing spacer, it disintegrates and comes apart , the balls just all clump together . Ive had the failure, but no metal got past the long engine screen, where oil is feed to the filter.

    What ever debri you had make it to the filter, went through the oil pump.
    Last edited by spud786; 11-03-2019 at 08:23 PM.

  9. #8
    KTMTalk Member
    Join Date
    Jan 2010
    Location
    brisbane
    Posts
    512
    Images
    120

    Default Re: Metal in oil and engine locked up

    Some memories came back to me the other day that may explain things. I purchased the bike in 2002 the day I got it home I noticed the clutch slipping; pulled the plates to find the inner hub all broken into pieces where the steels connect. Seemed all the aluminium was still contained within the clutch I just replaced the inner hub and called it good. I rode it hard for 6 months then had a bad accident. The bike has been parked up for 17 years only started once every year or 2 as I left on the family farm. I recently pulled the top end because it had lost power, I found the ring gap was out, the piston clearance was still good, the bore had ring burn at tdc and there was a scratch down the cylinder consistent with the oil ring height.

    So maybe some metal from the inner hub made it passed the filters and got into the bore, and that metal has been floating around in the oil for all that time. I have done a few oil changes over the years but it was so long ago I can't remember if I changed those filters. I think i would have st least once but in not certain.

    So now I just had the cylinder re plated and just run in and had the engine locked up, I pulled the top end again today to find a peice of plating chipped off so its back to the shop for replating.

    I had completely fogoten about the inner hub breaking up, has any one had that problem? All the ridges that connect to the steel plates were broken off

    Spud I'll check the oil pump also does that require spliting the cases ?
    Current bikes
    16 ktm 380 custom build http://ktmtalk.com/showthread.php?543034-2016-ktm-380
    06 ktm 380 custom build http://ktmtalk.com/showthread.php?54...ld-restoration
    04 Ktm 525
    98 ktm 620

    Previous bikes
    09 Ktm 300
    2000 fe 600 x2
    02 ktm 520(540cc)
    95 Ktm 620
    90 xr 630
    90 tt250
    91 kx 250
    83 yz 125

  10. #9

    Default Re: Metal in oil and engine locked up

    Not a center case split, just the right side cover. which may require certain counter balancer timing remounting the cover.

Similar Threads

  1. Engine locked up....again. ()
    By ProspectorJim in forum 4 Stroke KTMs - 2005.5 to Current, 250cc to 500cc
    Replies: 18
    Last Post: 03-24-2012, 12:34 PM
  2. Big problems engine locked up , 450 sxf (engine locked up during riding)
    By demorak1 in forum 4 Stroke KTMs - 2005.5 to Current, 250cc to 500cc
    Replies: 20
    Last Post: 10-03-2009, 12:22 PM
  3. '06 525exc engine siezed (engine locked)
    By 260rob in forum RFS-Racing 4 Strokes
    Replies: 8
    Last Post: 06-02-2009, 09:19 PM
  4. 06 250 sxf engine locked up (Is this possible?)
    By DrDirt221 in forum 4 Stroke KTMs - 2005.5 to Current, 250cc to 500cc
    Replies: 8
    Last Post: 08-18-2008, 09:19 PM
  5. MXC 450 Engine Locked UP HELP!
    By codyjay in forum RFS-Racing 4 Strokes
    Replies: 2
    Last Post: 09-25-2005, 07:04 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •