alright.... im confused

Message

ACEwrench · #1 Post by **ACEwrench** » Fri Mar 16, 2007 2:51 pm

i recently have been frustrated by a coolant leak from the weep hole so i decided id replace the cam cover (Aluminum) and gaskets as well as the seal behind the impellar...i do this in-frame..not a big deal it just takes some time to get enough of the harness, TB, supports, yadda, yadda out of the way. i get the old cover off and discover my exhaust cam has a rounded lobe...DAMMMITTT #@$%$#@ (those are curse words BTW) i luckly have 2 spare parts motors sitting around so i nabbed a cam off one check the decomp for function...check...install new cam ( after i dropped motor of course..and more curse words) check shim w/ feeler gage....check, we good...timimg is set..check ....side cover, new cam cover,gaskets,installed and walla, repaired engine. i installed the engine..i have a supermoto race next weekend so im very careful to locktite,lube,dieletric grease everything and i finally get to start it up...nothing...meaning it wont start...it will turn over i even put the battery on a tender to make sure it was fully ready to go...i think well ill reset the TB okay..nothing...i finally get it started for a moment after the battery was worn down once and of course, curse words. i runns but not well and dies after a few moments. it doesnt miss...idled smooth but ANY involvement with the trottle would just about kill it...it dies...2 worn down battery tries and curse words later it lites up again same result..i rechecked all mt connections..took off air box...checked TB connections, i checked to see if injectors were firing with a flashlight...yep...so now im confused...i even changed maps. BTW this was a running engine before i did this...very good running engine. HELP! just a side note it does backfire so i know its getting spark ( do have a spare coil too so ill check that and up date)

NorCalRacer · #2 Post by **NorCalRacer** » Fri Mar 16, 2007 4:40 pm

QUOTE (ACEwrench @ Mar 16 2007, 02:51 PM) <{POST_SNAPBACK}>

i recently have been frustrated by a coolant leak from the weep hole so i decided id replace the cam cover (Aluminum) and gaskets as well as the seal behind the impellar...i do this in-frame..not a big deal it just takes some time to get enough of the harness, TB, supports, yadda, yadda out of the way. i get the old cover off and discover my exhaust cam has a rounded lobe...DAMMMITTT #@$%$#@ (those are curse words BTW) i luckly have 2 spare parts motors sitting around so i nabbed a cam off one check the decomp for function...check...install new cam ( after i dropped motor of course..and more curse words) check shim w/ feeler gage....check, we good...timimg is set..check ....side cover, new cam cover,gaskets,installed and walla, repaired engine. i installed the engine..i have a supermoto race next weekend so im very careful to locktite,lube,dieletric grease everything and i finally get to start it up...nothing...meaning it wont start...it will turn over i even put the battery on a tender to make sure it was fully ready to go...i think well ill reset the TB okay..nothing...i finally get it started for a moment after the battery was worn down once and of course, curse words. i runns but not well and dies after a few moments. it doesnt miss...idled smooth but ANY involvement with the trottle would just about kill it...it dies...2 worn down battery tries and curse words later it lites up again same result..i rechecked all mt connections..took off air box...checked TB connections, i checked to see if injectors were firing with a flashlight...yep...so now im confused...i even changed maps. BTW this was a running engine before i did this...very good running engine. HELP! just a side note it does backfire so i know its getting spark ( do have a spare coil too so ill check that and up date)

If you're getting gas I would have to guess a sensor isn't functioning perfect, just a guess. After I did my cam -cover I had almost the exact same problem. I racked my brain, finally took the crank sensor out and cleaned it really good (didn't appear dirty, but....) and the quad fired perfect. I could be wrong here when the real experts pipe up, but maybe that will help. Good luck.

wistech · #3 Post by **wistech** » Fri Mar 16, 2007 5:09 pm

Throttle body boot or cam timing is off.

cannondale27 · #4 Post by **cannondale27** » Fri Mar 16, 2007 5:42 pm

Also if the lobe on cam that was rounded was directly opposite the decomp on exhaust cam you need to have the bucket bore machined.That is the one that sticks and it is good chance it will wear out your new cam.

thedeatons · #5 Post by **thedeatons** » Fri Mar 16, 2007 7:10 pm

He didn't mention new cam as in NEW... did ya happen to check the lobe on the "new" one for sharp edges (meaning soft cam material -BAD-)... I just found that on my wife's Glamis head, thought everything was fine but crappy intake cam.... I know I didn't help your situation, just throwing that out there...

cannondale27 · #6 Post by **cannondale27** » Fri Mar 16, 2007 7:48 pm

Yea that stinks.To me a used cam that has survived is more valuable than a new one since I know its good.Latest batch from Caniboomer seems to be really good though.Two Holers though.

ACEwrench · #7 Post by **ACEwrench** » Mon Mar 19, 2007 4:41 am

TB boot???? you lost me.... im starting to lean towards timing..i am assuming ,if it is, ..it is just a "CH" off but i will reset it just to be sure...im just frustrated right now.......... i replaced the bucket (it was dished) as well as the "new" cam. the cam was not new it was indeed used,but barely had ANY signs of wear on it. i am realy dreading dropping te engine again but i gotta do it...thank fo the help so far guys.

wistech · #8 Post by **wistech** » Mon Mar 19, 2007 4:52 am

If the TB boot (throttle body) is folded under the clamp it may be leaking air in and causing a very crappy running engine that will be hard to start with a lot of backfiring up the intake.

As far as cams go I will take a old high mileage cam with no wear over an new cam anyday. If they survive 50 hours or more and still have the coating on them they were heat treated correctly and are priceless. . With new cams its a crap shoot. Thats why many of us have been sending all the new cams in to be heat treated again with the titanium nitride treatment before they go in an engine.

ACEwrench · #9 Post by **ACEwrench** » Mon Mar 19, 2007 7:11 pm

no this cam was most definately used...and it did look nearly perfect.the guy who owned the engine before me didnt know a hole bunch about dales but he was very particular about oil changes...filter changes.ect. ect. it came out of a cannible the engine had a mag cam cover, no breather updates, it had the stronger, original case.

checked the boot and it was fine so im going with my original thought of timing...i didnt think the motor would run at all if the timing was off even one tooth???

Blazinmoto · #10 Post by **Blazinmoto** » Mon Mar 19, 2007 8:56 pm

I had a very similar problem and after days of trouble shooting turned out to be left injector. The conecter was not making a good enough conection. I zip tied it on tight and solved problem.