View Full Version : I need help on this LT80

12-05-2006, 10:15 AM
I have been working on this quad for a buddy. When he brought it over it didnt run. Well removed the carb and cleaned well...then changed the o-rings and changed the spark plug. After all that i put it back together and hit the starter. It started up after cranking a while and ran for about 5 min. and then bogged and died. And wouldnt restart.I cranked for a while and it kinda speeds up like it gonna start but just wont. I let it set for awhile and bam it started agian..and then the same thing, after about 5 min. of running it just boggs and dies.

I did a compression check and got 125, so im ok there.

But i did notice a lot of oil on top of head. I cleaned it off and when i ran it till it died i noticed that all that oil was back. Could i have a blown head gasket?

12-05-2006, 12:27 PM
an update...I got it started agian and rode it around for about 30min. When i first get it started it will idle no problem..when i ride it as long as i keep on the gas and dont be stopping, it runs fine. But if i stop and it idles for more then 10-15sec it will just fizzle out and die and wont restart.

I cleaned the top of the head off agian before the 30 min. ride. After it died 30min later, I pulled the plug boot off and there was more or oil/fuel then ever. It even covered the whole sparkplug inside the boot. Im not really sure where its coming from. Or is that normal? I have a banshee and a polaris 90 and neither one of them 2-strokes do that. But i would say it has something to do with why it acts the way it does.

12-05-2006, 01:01 PM
It's not normal.
Like you, I suspect a head gasket. Remove the plastic and take a look. If the head nuts are loose, the base gasket may be it or both. I'd replace botk anyways while that far into it.
Yes you have good compression.
You did have the carb all apart and clean (removing both jets and looking thru the holes)?

12-05-2006, 01:05 PM
cleaned it soaked it and removed the jets put air thru the holes. Its just wierd. I have fuel,air and spark. Would a head gasket make it extremly hard to start?

12-05-2006, 02:17 PM
Well the head bolts where tight but not tight enough for spec. I retighten them and it started once and ran for a few so i shut it off and tried to restart it and nothing. It just cranks and cranks, it does speed up and it tries to start but just wont.

Im gonna clean the carb agian and see what happens.

12-05-2006, 05:30 PM
Well i cleaned agian and still the same thing.

12-06-2006, 08:52 AM
I'd say your down to the base/head gasket. Either could be causing it now that the carb issue is eliminated.
This could be crank seals also.
The hard start points toward an air leak.
Next time it's running, spray wd-40 around the carb, cylinder, and stator. That may point you to a leak.

12-06-2006, 08:43 PM
Well LT80 i think its a crank seal. I took all the plastic off around the engine and the fan thats on the fly wheel. After i start it and let it warm up,after about 3-4 min. it wants to die at idle. And then i noticed oil leaking from behind the flywheel. After i shut it off i had a steady stream running out.

12-07-2006, 09:09 AM
I'm glad you found it.:)

12-07-2006, 03:32 PM
Would a bad crankshaft seal cause the symptoms i have? Also does it require me splitting the case?

12-07-2006, 03:55 PM
Well that's why you needed to be 100% sure the carb/reed cage is sealed.
Yes the crank seal will do what it's doing.
They are simple. Pull the stator off and it prys right out.
They're only like 6 bucks each. Might as well do the clutch side too.

12-07-2006, 04:09 PM
I did the WD-40 trick you told me, and i soaked the carb, intake, reed cage and all around the head and jug. and had no problems. But i can see the oil running from out behind the flywheel. Now do i need to have a special flywheel puller like some other quads?

12-07-2006, 09:58 PM
You need a puller with 2 opposing slots and you use the fan holes w/bolts.
It would look like ====o====..LOL
Don't confuse that with (___O___)..<-the moon.
LMAO :D :D :D :D

The puller has to be equall! MUST PULL STRAIGHT!
Sand the stator and flywheel while off. :)
It's pretty easy.

12-10-2006, 04:09 PM
I just would like to say, Thank you LT80 for all your help diagnosing the problem. You was right it was a crankshaft seal. I replaced it and the quad runs like new agian.

Thanks Rob

12-11-2006, 08:29 AM
Your very welcome. :)
Happy to help.

12-16-2006, 04:59 AM
Originally posted by banshee_bandit
I just would like to say, Thank you LT80 for all your help diagnosing the problem.

That is why he is Mr. LT80! LOL Jack is the man