Cylinder Base Sealants

[Vintage Engine Repairs]

"permatex aviation form-a-gasket 3"

I used this stuff WAY back on military vehicles with respect to gas contact....because it was so hard to get real gaskets and I hadn't learned yet how to make my own gaskets. And then when I did learn, I used this stuff to dress the gasket lightly. I tired everything else back in the day available to me in a small mountain town area.....nothing else held up against gas contact.

But I've never deleted the base gasket on a chainsaw, so I can't speak with any authority there.

Kevin

Fascinating, thanks Kevin!

I wouldn’t use this in place of cylinder base gasket, But maybe it would work? Depending on how flat the surfaces are. However it may also just blow out.

I’d love to get a tube of 1184 and try that but it’s not sold in Australia. Sounds like it has much longer work time that motoseal.

 

[Real1]

Fascinating, thanks Kevin!

I wouldn’t use this in place of cylinder base gasket, But maybe it would work? Depending on how flat the surfaces are. However it may also just blow out.

I’d love to get a tube of 1184 and try that but it’s not sold in Australia. Sounds like it has much longer work time that motoseal.

I have a tube of 1184, but never used it for anything. Like I said, I've never done a base gasket delete.

What I will tell you is that I was putting compressed air into a Husky 2100 oil tank and POP went the tank! What I had stupidly managed to do was split the tank halves seam. I went down a LOOOOONG, deep rabbit hole in trying to re-bond those tank halves. Tried the Yamaha, Honda sealants. Didn't work....because without reinforcement like screws/clamps, the halves looked like they needed(and had originally) an epoxy bond of some kind.

I bought a commercial construction epoxy that was supposed to impervious to just about everything. I super cleaned the two bonding surfaces. Applied the epoxy and let set for three days clamped in mild temps. Saw ran with no leaks for six months and started leaking again. The weak link seems to be at the rear of the handle.....which on some models(seemingly random, Husky-wise), they had a factory screw for reinforcement.

Needless to say, that took the wind outa my sails on bonding gas/oil tank halves. After that I got paranoid and started picking up used tanks....lol. Most of which have at least two threaded holes buggered and "repaired" with JB Weld......so there was always work to do on the tanks before they could go back in service.

My educated guess is that Husky had probably a clinic like environ when they bonded those tank halves together and of course the magnesium was virgin too. I envision people with operating skivvies and masks.......

Kevin

 

[Stump Shot]

Old McCulloch(10-10's and variants of) had nothing but clear silicone sealing the bottom clam to the upper block that I've noticed and even at 30 - 40 years old were still holding up.
Maybe at least some of our worry is unwarranted quite possibly?

 

[Real1]

My educated guess is that there is a lot of sealant material there for the gas mix to denigrate and get access to. Probably such a slow process that it's not a consideration with the folks that use modern sealants and delete the base gasket.

Kevin

 

[Nutball]

Off the top of my head these are the only saws I don't use a gasket on.

Stihl MS201T
Stihl MS150T
Echo CS-2511T
Echo CS-590
Husqvarna 395XP
Husqvarna 346XP

Why not on the 395? I was thinking of reusing my 395 gasket since the cylinder came clean off it and just machine the cylinder as normal.

I like 1184, it doesn't set up too fast, but the strings are annoying. I apply it with a Q-tip either dabbing it on thinly to both surfaces, or just applying a very small bead around the outer edge of the mating surface so that as it squishes, little will make it inside the engine and more makes it outside.

Echo uses 1184 on their 490 transfer caps.

 

[Bob Hedgecutter]

My educated guess is that there is a lot of sealant material there for the gas mix to denigrate and get access to. Probably such a slow process that it's not a consideration with the folks that use modern sealants and delete the base gasket.

Kevin

Exactly, not like the crankcase is swimming in fuel up to the level that the cylinder bolts on- and the thread is about suggested sealers for that joint if the gasket might be deleted.
If it is you might have a slight flooding problem.

 

[Vintage Engine Repairs]

Anyone willing to sell / send me a couple tubes of Threebond 1184 you use in the states?

Online postage says it’s like 60 Australian dollars! Surly it can’t be that much?

 

[Mastermind]

Why not on the 395? I was thinking of reusing my 395 gasket since the cylinder came clean off it and just machine the cylinder as normal.

I like 1184, it doesn't set up too fast, but the strings are annoying. I apply it with a Q-tip either dabbing it on thinly to both surfaces, or just applying a very small bead around the outer edge of the mating surface so that as it squishes, little will make it inside the engine and more makes it outside.

Echo uses 1184 on their 490 transfer caps.

Two places on the 395 jug get too thin for my liking. Where the impulse fitting is, and at the rear bolt lugs.

 

[Vintage Engine Repairs]

Just checked both msds sheets for 1184 and 1104 neo. It’s the same product but 1184 has one less chemical (thanks to California no doubt). I can get 1104 neo here.

 

[RedneckChainsawRepair]

Just checked both msds sheets for 1184 and 1104 neo. It’s the same product but 1184 has one less chemical (thanks to California no doubt). I can get 1104 neo here.

It started out 1104 then 1194 then 1184. Can you say EPA

I have a old thread on it years back. Why and 1104 1194 1184 =
Threebond 1104 (Discontinued because of hazardous chemicals)
Threebond 1194 (Discontinued because of hazardous chemicals)

I was using a tube of 1194 I found yesterday.

 

[Real1]

Just checked both msds sheets for 1184 and 1104 neo. It’s the same product but 1184 has one less chemical (thanks to California no doubt). I can get 1104 neo here.

Sounds like maybe the older version is better with the chem it had.....if you can get that one there, jump on it!

Kevin

 

[Vintage Engine Repairs]

Sounds like maybe the older version is better with the chem it had.....if you can get that one there, jump on it!

Kevin

I have actually used 1104neo and liked the slower set time, but after some time In fuel turned to a puddle of mush - I had hoped the 1184 was better, but I don’t suppose so!

Motoseal stayed solid and that’s why I stuck with it. I’d be curious to see if anyone with 1184 can cure a thin sample and see if after 24 hours in fuel if it just turns to mush too?

 

[Nutball]

Two places on the 395 jug get too thin for my liking. Where the impulse fitting is, and at the rear bolt lugs.

Have you ever experienced a failure in those areas or heard of a failure from cutting the extra off to keep the base gasket? I was thinking of cutting .043" off the base on mine and using the gasket. I see where those areas would be thin, but I don't think it would be thin enough to cause problems unless it is a known failure point due to getting too thin. I'd like to keep the gasket, but will cut less off the base and use 1184 if you know it is likely to fail.

 

[Mastermind]

Have you ever experienced a failure in those areas or heard of a failure from cutting the extra off to keep the base gasket? I was thinking of cutting .043" off the base on mine and using the gasket. I see where those areas would be thin, but I don't think it would be thin enough to cause problems unless it is a known failure point due to getting too thin. I'd like to keep the gasket, but will cut less off the base and use 1184 if you know it is likely to fail.

I've never cut enough off to try Remington.