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Main Area => General GS500 Discussion => Topic started by: patwcon on August 16, 2008, 06:11:44 PM

Title: changed cam chain tensioner -- will turn over but not start.
Post by: patwcon on August 16, 2008, 06:11:44 PM
The cam chain tenisoner on my '90 GS500 broke last July.  After sitting for a year I replaced the tensioner (followed the 1,2,3 timing instructions), cleaned  carbs, changed plugs etc.  The bike turns over easily, fuel is getting to the carbs and I have spark but the damn thing won't it start.  It doesn't even sound like it's going to start.

Any help would be appreciated.

Pat
Title: Re: changed cam chain tensioner -- will turn over but not start.
Post by: beRto on August 16, 2008, 06:20:11 PM
Quote from: patwcon on August 16, 2008, 06:11:44 PM
The cam chain tenisoner on my '90 GS500 broke last July.  After sitting for a year I replaced the tensioner (followed the 1,2,3 timing instructions), cleaned  carbs, changed plugs etc.  The bike turns over easily, fuel is getting to the carbs and I have spark but the damn thing won't it start.  It doesn't even sound like it's going to start.

Any help would be appreciated.

Pat

Given that you recently messed with the engine timing, I'd start there - I suggest double checking that the timing was set correctly.
Title: Re: changed cam chain tensioner -- will turn over but not start.
Post by: Mdow on August 18, 2008, 05:32:09 AM
did you turn the auto tensioner with a screw driver when you reinstalled it?
Title: Re: changed cam chain tensioner -- will turn over but not start.
Post by: patwcon on August 18, 2008, 06:33:41 AM
yes, the new tensioner came tightened with a clip in it.  I installed it and pulled the clip out.  The chain is tight and, according the manual, the timing is right on.  There must be something else wrong.  I took the whole thing apart again last night and re-did it.... Still will not start.
Title: Re: changed cam chain tensioner -- will turn over but not start.
Post by: werase643 on August 18, 2008, 07:55:04 AM
compression test results are?

Title: Re: changed cam chain tensioner -- will turn over but not start.
Post by: patwcon on August 18, 2008, 07:35:18 PM
Ok, I give.  I have had the top off the motor a dozen times... why would I need to check the compression now?  Please let me know what could be wrong.

Thanks for your help.

Pat
Title: Re: changed cam chain tensioner -- will turn over but not start.
Post by: coll0412 on August 18, 2008, 09:17:46 PM
Well have you tried spraying a little fuel into the carbs to see if it at least fires a bit.

Since you said you have cleaned the carbs so you may have screwed up something there as well. Did you start it after cleaning the carbs or where all the repairs made simultaneously.

The reason werase643 asked about the compression is that if the cams where off you could possibly have low compression on "compression stroke". You can do the thumb over the spark plug trick to do a rough check.
Title: Re: changed cam chain tensioner -- will turn over but not start.
Post by: werase643 on August 18, 2008, 10:57:34 PM
engine broke
replaced tensioner

top end of engine off several times?

simple diagnostics
to have a fire...need 3 things....fire triangle....remember scouts were good for something
fuel.... no fuel....carb problem
air..... no air.....could be carb problem or valve problem  (if low compression...the Buddha Loves You won't run)
sparky.... no sparky.....electrical problem

if the top end was off.... did you check the valves, are they sealing properly,

it ain't rocket science....but not all 3rd graders can do it either

do a compression test
check the sparky
spray some gas into the intake ports while the carbs are off and see if it will hit a couple of times

Title: Re: changed cam chain tensioner -- will turn over but not start.
Post by: yamahonkawazuki on August 18, 2008, 11:07:35 PM
yup cannot have a running engine without all of the aforementioned
Title: Re: changed cam chain tensioner -- will turn over but not start.
Post by: patwcon on August 21, 2008, 06:31:44 PM
Thanks for the responses.  I gave up and took it to a shop.  Looks like I need to have the valves replaced.  I just have to decide if I want to put that much money into fixing it.  Waiting on the shop to tell me how much it will cost.

Pat
Title: Re: changed cam chain tensioner -- will turn over but not start.
Post by: The Buddha on August 21, 2008, 06:56:12 PM
Valves replaced ... hey, I have this beautiful bridge for sale in the nice little town of New York ...
OK before you buy my bridge, did the tensioner break while riding ???
You hear loud banging noises before it stopped ???
You are turning over free without clanging noises ???
Your spark plugs come out all smashed ???

If yes to any of these, you broke a valve when you lost the tensioner.

Else, find another dealer, or bring it to my house in charlotte NC.
Cool.
Buddha.
Title: Re: changed cam chain tensioner -- will turn over but not start.
Post by: werase643 on August 22, 2008, 01:48:02 PM
I think i have a head with fresh valve job....

you could pick it up on the way to budduh's house.....it it is in my pit of dispare
Title: Re: changed cam chain tensioner -- will turn over but not start.
Post by: patwcon on August 23, 2008, 07:24:21 PM
haha!!!  DID NOT BRING IT TO A DEALER ( I wasn't born yesterday!)... will probably let the shop fix it in November when I get back stateside... $750 isn't much to get it back on the road.  I like a "project bike".  Plan on buying a new something then as well.  The Speed Triple has caught my eye.

Pat