Blown base gasket.....Why?

[88lt250racer]

Ok, I just put about 10 hours on my new top end and my base gasket blew under the intake. I noticed it leaking and thought it was no huge deal until it got to the point it would'nt hardly run. I pulled the jug off and the gasket is actually broken. I know it wasnt broken when I assembled it. What caused this to happen? Also, I used Cometic gaskets and I just bought a Suzuki base gasket and it seems to be thicker with an o-ring type surface all around it. Could Cometic be the problem?

[flotek]

cometic gaskets are steel and dont do that ,stock gaskets for anything other than the head usually suckass in comparison to a cometc IMO.your jug is probably not flat under that area due to warpage and or age and wear. check it for flatness , whats your compression ?leaking gaskets anywhere around your cylinder are always a big deal .

[88lt250racer]

I know the base gasket I installed was not steel, it was the paper type and thats the type that was on the base when I tore it down and it never leaked before. Just trying to figure out what caused it to blow shortly after I assembled it. I have done many top ends and never ran into this problem. The old gasket appeared to have a sealant applied to it. Should I have used a sealant during assembly?

[Zilladude]

I always use a little Permatex High Tack on the intake side of the base gasket on the 500. I have never had a failure yet. I only use suzuki or k&s gaskets, I think cometic base gasket suck on the LT's

[flotek]

i cant remeber the exact style cometic gaskets for lts (too traumatic i blocked it out)
i know for shes ,cometic are all steel and are pretty darn leak proof and sweet , if there was already silicone there than that may be an indication the previous owner had leakage problems there also . like i said , it (cylinder bottom)may be very unflat and /or worn and warped over the last 17 years of use.

[Flattrack]

DID you ever recheck the torque after a couple heat cycles...Always go over every bolt and nut on what ever you had a part a couple times after you run it....

[Kane]

ANY leak is a HUGE deal, bro. NEVER let a leak run longer than it's discovery. Unfortunately, that nice metal base gasket is only used on a few machines. Very few companies make it for the LT or any other quad for that matter. Hit your local machine supply company and get a sheet of .030 copper shim stock and cut your own.

[suzuki LT250R]

Originally Posted by Kane

ANY leak is a HUGE deal, bro. NEVER let a leak run longer than it's discovery. Unfortunately, that nice metal base gasket is only used on a few machines. Very few companies make it for the LT or any other quad for that matter. Hit your local machine supply company and get a sheet of .030 copper shim stock and cut your own.

and the good thing about this is that you can reuse it. Just heat it up and it will expand and when you use it it will mash it down again.

[370banshee]

you gotta put permatex on the gasket intake and exhaust side.. not the whole ting but suzukis are horrible for blown base gaskets.. also did you do what wade said... youi;d be surprised how much the nuts will back off after a few heat cycles.... just like alum wheels on your truck you gotta check em after a small bit of use then tighten them and they'll stay tight....

[zillaguy89]

Originally Posted by 370banshee

just like alum wheels on your truck you gotta check em after a small bit of use then tighten them and they'll stay tight....

Darn tootin! you wouldn't believe how many times I've seen wheels come off from customers not listening to me when I say "come back in in a day or 2 after you put about 50 miles on these new wheels so I can re-torque them." Aluminum is strange sometimes, especially if it is exposed to heat