Thread: 89 LT 250R keeps blowing base gaskets?

Ok thanks guys. I will see if he will pull the motor and bring it to me, for dowel / stud inspection. Then I will assemble it for him. I will advise him of that Cometic gasket SBLT..I like them things.They work well. If that is not an option, I will go with the "right stuff" that Jason suggested.

Quote: Originally Posted by cr480r lt250's almost always need to be machined to eliminate misalignment of the case halves. after the cases are fixed its best to remove the head stay and use copper base gaskets or try the rcm gaskes mentioned above. if you are heavy guy or jump alot the base gasket will blow everytime if the head stay is used.. good luck! um...... im a big guy and i raced a lt250 just about all through the 90s and i have...

i was thinking cr480r must be joking lol

the only thing i can think of is not torquing the bolts down or the gaskets arnt the right ones a guy i knew had that problem and it was because the gaskets werent a perfect match

A few things come to mind when I think about that. The first Is, could he be tightening one corner of the cylinder Very Tight before snugging the opposite corner???? Could one dowl pin be bottoming out before the 2 mating surface's touch. If all else fails, then find some RITE STUFF!!! I swear by the stuff!!!! It's 14.00 for a small caulk tube, but will seal about ANYTHING. I use It on Caterpillar front engine covers, and they Never...

get a cometic RCM gasket. rubber coated metal. stronger then a paper gasket. come in different thicknesses to. it does sound like its not torqued correctly, or a stud is pulling out of the cases

lt250's almost always need to be machined to eliminate misalignment of the case halves. after the cases are fixed its best to remove the head stay and use copper base gaskets or try the rcm gaskes mentioned above. if you are heavy guy or jump alot the base gasket will blow everytime if the head stay is used.. good luck!

Quote: Originally Posted by Jason Hall A few things come to mind when I think about that. The first Is, could he be tightening one corner of the cylinder Very Tight before snugging the opposite corner???? Could one dowl pin be bottoming out before the 2 mating surface's touch. If all else fails, then find some RITE STUFF!!! I swear by the stuff!!!! It's 14.00 for a small caulk tube, but will seal about ANYTHING. I use It on...