426 head and cilender warped?


17 replies to this topic
  • 426brandon

Posted September 21, 2007 - 01:20 PM

#1

hey, i brought my 00 yz426 in to the shop for servicing, and i got the valves checked to, and now tonight, 4 days later they say that my head and cilender are warped, do you think this is true, or just a way to make money, and if it is true, how does this happen, thnx

  • grayracer513

Posted September 21, 2007 - 01:41 PM

#2

It could be true, but it's pretty rare. They would be talking about the flatness of the surface that seals the head gasket. Ask them how far out of flat they are, what the factory tolerances are, and what they suggest you do about it.

  • 78sharpshooter

Posted September 21, 2007 - 03:38 PM

#3

I'd say it is BS because unless the service called for pulling the head then how the heck do they know it is warped?

  • grayracer513

Posted September 21, 2007 - 04:02 PM

#4

If you're saying that it's still bolted together, then it is BS. The only way to know is to put a straight edge on the surfaces.

They could determine that it has a leaking head gasket if they did a leak down test on it, but I doubt they did.

  • 426brandon

Posted September 22, 2007 - 01:03 PM

#5

i dont know, it was leaking coolant, and i brought it in and told them to fix the leak and i want it fully serviced, and then they called last night and i went to go see it this morning and the list of parts keeps getting biker, now im up to

full service
valve adjustment
getting the head and cilender machined
new cam chain
rings
some gear things
new drain plugs
gaskets

wow, i dont know if this is going to be for the better or worse, i bring the bike in for a servise and i get this?? it better be worth it, it better run like new, and considering Rogers Sports Center in Fort Kent Maine has one of the best yamaha mechanics in the U.S., it should run good, but it will be a very big parts and labor bill!

  • 426brandon

Posted September 22, 2007 - 01:08 PM

#6

I'd say it is BS because unless the service called for pulling the head then how the heck do they know it is warped?


they recomended that they check the valves, they said the valves in these bikes tighten up, so i went a head and had the valves checked

  • Florida_426

Posted September 23, 2007 - 07:03 AM

#7

With that riot list of parts and services I'd ask to see the dacking of the head and cylinder results and the original parts they say are needing to be replaced. As Grayracer said if they didn't remove the head how do they know it is warped? Head warped is possible but the cylinder is highly unlikely. Which gears need replacing? I'd ask to see the parts and speak to the tech about why the drew their conclusions. Listen to GR and ask lots of questions.

Best of luck with getting your scoot right and get a factory shop manual so you can do your own work, it is not rocket science and can be done.

Bill

  • 78sharpshooter

Posted September 24, 2007 - 11:28 AM

#8

I bet they found either a little oil in the coolant or vice versa and are assuming that the head is warped. You might only need a new head gasket. Personally, I'd say thanks but no thanks and network to find the most trusted shop in your area and take it to them.

  • 426brandon

Posted September 27, 2007 - 02:04 PM

#9

they said even if i get a new head gasket it wont help cuz the head is so warped, it wouldnt seal, and that there was a scar in the cylender

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  • grayracer513

Posted September 27, 2007 - 02:38 PM

#10

If the head is on the bike, how do they know that?

  • Polar_Bus

Posted September 28, 2007 - 02:31 AM

#11

hey, i brought my 00 yz426 in to the shop for servicing, and i got the valves checked to, and now tonight, 4 days later they say that my head and cilender are warped, do you think this is true, or just a way to make money, and if it is true, how does this happen, thnx


Was your bike loosing coolant, or puffing white smoke out the exhaust before it went into the shop for a valve adj.? This is a tell tale sign you have a blown head gasket, and possibly a warped head. Too many details missing from this post about this situation.....

  • USED YZ426F

Posted September 28, 2007 - 06:38 AM

#12

i dont know, it was leaking coolant, and i brought it in and told them to fix the leak and i want it fully serviced,


That is a very trusting thing to tell a service department. They are probably looking in to buying new cars with everything that your bike will need.

Never tell a service department to fix problem "A" and then service your bike without knowing exactly what they are planning on doing and how much it would cost.

  • USED YZ426F

Posted September 28, 2007 - 06:43 AM

#13

If the head is on the bike, how do they know that?


I guess that they could put a bore scope down the spark plug hole with the piston at BTC, but I seriously doubt the did that, or even have a bore scope.

I would take my bike back and ask around for other shops. Also, never tell the service department to "Give your bike a full service". This tells them to just go nuts on stuff and start planning that vacation to Hawaii - at your expense.

  • Polar_Bus

Posted September 28, 2007 - 06:50 AM

#14

I guess that they could put a bore scope down the spark plug hole with the piston at BTC, but I seriously doubt the did that, or even have a bore scope.

I would take my bike back and ask around for other shops. Also, never tell the service department to "Give your bike a full service". This tells them to just go nuts on stuff and start planning that vacation to Hawaii - at your expense.


The only true way to know of a blown head gasket to my understanding, is to use a motorcycle "leak down" tester. Never heard of using a bore scope. What exactly will they see?

  • USED YZ426F

Posted September 28, 2007 - 03:31 PM

#15

The only true way to know of a blown head gasket to my understanding, is to use a motorcycle "leak down" tester. Never heard of using a bore scope. What exactly will they see?


I was referring to 426brandon saying that there was a scar in the cylinder and grayracer513 asking how that could be known with the cylinder still on the bike.

Think of a bore scope as a small camera on the end of a flexible wand. Sorta like that thing they put up one's bottom to check for colon trouble. You can see the inside of a bore (in this case the cylinder) without having to disassemble the whole top end. It is really only good for checking stuff like carbon build up, bore scoring, and possibly valve damage.

I've used them to check diesel engine cylinders without having to tear apart the entire top end.

I would seriously doubt that a service department would have a bore scope, especially when they could just as easily pull the head and cylinder and charge us for the additional labor and gaskets to put it all back together.

  • 1rkcooper

Posted September 28, 2007 - 03:48 PM

#16

hey, i brought my 00 yz426 in to the shop for servicing, and i got the valves checked to, and now tonight, 4 days later they say that my head and cilender are warped, do you think this is true, or just a way to make money, and if it is true, how does this happen, thnx




Did you ask for a valve adjustment or tell them to check the valves, if it was check the valves they may very well have taken the head off to check the valves.
If you asked for a valve adjustment then there is no need to pull the head off. Ask why they took the head off, if indeed they did, tell them to put it back together and get an itemized bill from them that breaks down the parts and labour for everything they have done. Then tell them you are not paying for the gaskets and labour for the removal and installation of the head.
IMO you can only do this if you asked for a valve adjustment. To check the valves they may want to actually look at them $$$.

  • 426brandon

Posted September 29, 2007 - 04:35 AM

#17

I told the shop to check the valves, they took the head off, the head is at a machine shop right getting plained (tru flat) so they can see all this stuff, and i told them i have a coolant leak, and my exaust had a weird white smoke coming out the last ride, so these guys didnt take the top end apart for nothing, i told them what was wrong and it needed to be done.

  • 1rkcooper

Posted September 29, 2007 - 02:44 PM

#18

Well they did what was asked and needed then. I would hazard a guess that the bike has been overheated at some point if the head is actually warped. The white smoke may have been just a blown head gasket which could be a result of overhrating and possibly warping the head. I can't think of another way you could end up with a warped head unless the motor was taken apart and the head not torqued down properly when put back together.





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