# BP-250 cylinder base gasket



## powertweak (Oct 31, 2005)

I recently put new rings in my Homelite BP-250 backpack blower along with rebuilding the carb. It ran good afterwards, but was leaking fuel/oil mixture from the cylinder base gasket area, especially on the carb side. I pulled it back apart and did not see anything that jumps out at me. The new base gasket was split in that area, but I assumed that happened during disassembly, but could have happened when I installed it I suppose. If I did split it during assembly, that would explain the leak. However, I noticed during disassembly there appeared to be a good amount of fuel/oil mix on the gasket surfaces. Any thoughts? Should I coat both sides of the new gasket in permatex or something like that? Hopefully I won't be taking it apart again. By the next time it quits it may be time for a new blower. thanks.


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## hankster (Jan 1, 1998)

Those blowers are well known for the carb bolts coming loose and many times the cylinder bolts coming loose. The second would explain the "wet" gasket but that is pretty normal on inexpensive 2-cycle engines. The gasket should not be split, get a new gasket and replace the bad one.


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## powertweak (Oct 31, 2005)

So Hank, would you recommend coating the new cylinder base gasket with non-hardening Permatex? I was also considering changing the cylinder base screws to a hex head so that I could get them tighter with a wrench as opposed to the torx head on the OEM. Maybe use blue locktite on the threads too. What do you think? Thanks for the advice.


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## hankster (Jan 1, 1998)

If you use a new gasket then you shouldn't need any type of sealer. At the most some silicone sealer can be used... not a lot of pressure in the crankcase. Husky equipment doesn't even use a gasket... all they use is silicone sealer. I don't remember right off hand but I think the screws they use are a self tapping screws so the only way to use another one would be to drill and tap cylinder... but I could be wrong on that. Not many Homelite blowers get rebuilt because the parts are so expensive. Locktite wouldn't hurt... heck, might as go with Red as it's unlikely you would ever rebuild it because of the cost.


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## powertweak (Oct 31, 2005)

This time, the new gasket has an embedded red silicone ring on 1 side. The replacement gasket I received when I installed the new rings did not have this. Question is, which side mates to the silicone ring, cylinder or crankcase? I also went back and looked, Homelite recommends those cylinder base screws (12-24x3/4) be tightened to 55-65 inch lbs using red loctite. The loctite I have, but I don't have an inch lb wrench that will hold the torx bit required for those screws. Those screws appear to be harder than standard replacements that I could get with a hex head.


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## hankster (Jan 1, 1998)

Sorry I really can't tell you which side goes where as I've never really seen a blown gasket and had to replace it. Just tighten the screws tight, we don't use a torque wrench to tighten those bolts.


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## powertweak (Oct 31, 2005)

Wanted to follow up for the benefit of others who may search this thread for similar information. I spoke with Homelite Technical Assistance this morning. The red silicone ring imbedded into the cylinder gasket goes up, making contact with the cylinder base. This improvement was in response to customer complaints about the wet gasket leak that I had described. I questioned the tech about adding some gasket sealant to the crankcase side of the gasket and was told it would not hurt anything - I believe that I will do this and see what happens.


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## hankster (Jan 1, 1998)

Great... thanks for passing on that information!


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