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Old 11-11-2008, 04:38 PM   #1
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Default V-Spec issues... bearing looks great

Well about 2 weeks ago i was trying to run my vspec... If it was placed under ANY load the engine would INSTANTLY die... one of the guys at my local track said when his did that it was the bearings... well i posted on here that same week askin bout boca and TKO... i boughtt he tko's and just took the motor a part and both bearings seem GREAT... cant find any signs of damage or scoring... and the case looks good no cracks... I did how ever a week prior have a fuel line get pinched and i was on a long back straight and it lean out till it died... I also had new clutch bearings and they are being used now with another new vspec... please help me out... if pics are needed i can have them at anytime... Thank you...
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Old 11-11-2008, 05:03 PM   #2
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Also.. i jsut checked my carb settings.... maybe one hour differnt on the top end... I didnt copy them over either thats just where it ran the best...
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Old 11-11-2008, 05:04 PM   #3
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well my first thought would have been clutch trouble..
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Old 11-11-2008, 05:12 PM   #4
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check your carb boot as well to make sure that when you stretch it out it doesnt have a hole or leak. i always airseal mine and at the ball end and use a small tie wrap at the opposite end.
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Old 11-11-2008, 05:49 PM   #5
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whats it sound like when it dies? does it hesitate and die when u give throttle, or bog, or just flat out die ...?

but it starts and idles fine?

watch your flywheen to see if its locking/binding up or just spinning to a stop when it dies - im gonna give my worthless opinion and say you have a major airleak
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Old 11-11-2008, 05:55 PM   #6
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I would pop the throttle like 2 times and instantly once the clutch engaged it would die... it would idle on the bump box for a long time... sometimes it would die but only at hugher revs but only once every 10 times in higher revs... ALSO MOTOR HAS JUST UNDER 3 GALLONS...
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Old 11-11-2008, 06:06 PM   #7
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if your car can idle on the box without the wheels spinning and you can accelerate and brake without it dying its not the clutch springs. when u break a spring youll notice that one shoe drags and spins your wheels, when you brake its still holding and locks the motor

if its dying its got waaay toomuch air or waaay too much fuel- most likely too much air - a leak

ive had before too that my chassis got dented right before my flywheel and when the car bottomed out the flywheel would catch on the ground and shut the motor down
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Old 11-11-2008, 06:36 PM   #8
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Make sure there is no trash or o-ring debris floating around in the high speed needle assembly. I've had engines that would crank and idle fine but once you get on the gas at all they would bog and die, turned out to be a sliver of o-ring floating around in high speed needle.... just a thought.
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Old 11-11-2008, 07:06 PM   #9
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Any plug changes recently? What pipe are you running? Pressure line etc etc ok?
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Old 11-11-2008, 07:59 PM   #10
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Im using the same clutch now on a new vspec and it runs fine... its not the clutch... I did find a very small hole in the rubber boot right where the servo hooks to the ball link... its closed up in all positions but definately there... I will pull the needle valve and see if there is debris...
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Old 11-11-2008, 08:31 PM   #11
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Sounds like bearings to me. I've had ones that look fine not spin well, take the backplate off and spin the crank, watch the bearing to see if the balls are rolling at half the speed or sliding. It's hard to explain.

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Old 11-11-2008, 08:47 PM   #12
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I had the same issues with a Vspec. Caused me to loose two bump spots in two big races...

Couldn't for the life of me figure out why it would pop and puff and load up then flame out. Finally found a hairline crack in the case. I almost couldn't see it but could feel an edge to the crack with a brand new Xacto knife blade. Opened up the engine and could see the crack lots better. Check that good again...
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Old 11-11-2008, 08:50 PM   #13
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Quote:
Originally Posted by cwalters View Post
I had the same issues with a Vspec. Caused me to loose two bump spots in two big races...

Couldn't for the life of me figure out why it would pop and puff and load up then flame out. Finally found a hairline crack in the case. I almost couldn't see it but could feel an edge to the crack with a brand new Xacto knife blade. Opened up the engine and could see the crack lots better. Check that good again...

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Old 11-11-2008, 11:01 PM   #14
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How easy is it to get the rod off the crank pin? It should be some what difficult to pull the rod off when at TDC even with the sleeve out of the motor. Mine came off too easy & when I put new rod on it turns out my crank pin had worn & its not the first time I have heard of v-spec cranks wearing at 3-5 gallons. If you can push & pull the rod up & down on the crank pin & see the fuel oil residue squish out, rod or crank or both are worn beyond limits.

Pop & puff are signs or rod or bearing damage or damaged exaust port gasket sucking in air.
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Old 11-13-2008, 06:10 AM   #15
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thnx for all the help.. m goin to try it out again this weekend.. ill be sure before i reasseble to get it under good light and look it over again for a crack....
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