Gasket maker

[Vintage Engine Repairs]

Dirko HT Red isn’t fuel resistant either. I had a German friend contact Elring (who make Dirko) and specifically ask if Dirko HT Red is fuel resistant. “No” was their response and they recommended a totally different product.

 

[av8or3]

The PRC aviation sealants are absolutely fuel proof. The term B-1/2 refers to 30 min. pot time (working time) although from experience it’s lots longer. B-2 would indicate 2 hours working time. Also there is a sealant that is identified as A-1/2 or A-2. These sealants share the same working times as those above but FLOW like a thick paint. The “B” sealants do not flow, they have to be put into place, and sometimes held there until they set up.
There are also different colors. Grey and black.
These sealants will not stick to polyethylene or the other plastics used in small engine gas tanks.

 

[qurotro]

Too many times. Threebond kept failing to seal around the oil filter and it would push oil into the cooling system.

which Threebond? 1184?

 

[qurotro]

Dirko HT Red isn’t fuel resistant either. I had a German friend contact Elring (who make Dirko) and specifically ask if Dirko HT Red is fuel resistant. “No” was their response and they recommended a totally different product.

Funny thing is those clamp shell Stihl's use Dirko HT Red to seal the pan. Check the service manual and 0783 830 2120 is the sealant number.

 

[huskyboy]

Funny thing is those clamp shell Stihl's use Dirko HT Red to seal the pan. Check the service manual and 0783 830 2120 is the sealant number.

I have never had a problem with dirko. It’s all I use now for base gasket deletes. I like it better than any of the other sealants I have tried. However I wouldn’t use it to seal a fuel tank. I would prefer a actual “gasket” of gasket material. I tried sealant on a 056 gas tank. It did not work. Only the oem gasket or proper gasket material cut out to match seemed to work.

 

[USMC615]

3m weather strip adhesive. Also known as monkey snot. Is what omc used to seal tanks from the 70's up to the early 2000's. It comes in classic yellow and now more discreet black.

Good luck ever getting it apart if you go that route.


Steven

This...yellow 3M Weather Stripping Adhesive!

 

[Vintage Engine Repairs]

Funny thing is those clamp shell Stihl's use Dirko HT Red to seal the pan. Check the service manual and 0783 830 2120 is the sealant number.

Yes absolutely they do!

 

[Vintage Engine Repairs]

I have never had a problem with dirko. It’s all I use now for base gasket deletes. I like it better than any of the other sealants I have tried. However I wouldn’t use it to seal a fuel tank. I would prefer a actual “gasket” of gasket material. I tried sealant on a 056 gas tank. It did not work. Only the oem gasket or proper gasket material cut out to match seemed to work.

I agree, I have tried Dirko, Motoseal and 1104. Dirko is still my preferred sealant, it’s great stuff and compressed between mating surfaces, doesn’t contact fuel and holds really well.

 

[qurotro]

Hmm..

I agree, I have tried Dirko, Motoseal and 1104. Dirko is still my preferred sealant, it’s great stuff and compressed between mating surfaces, doesn’t contact fuel and holds really well.

1104 is NOT rated for gasoline. I just checked the data sheet. 1184 does specifically rated for gasoline. I haven't use 1184 for fuel tank repair though.

 

[srcarr52]

which Threebond? 1184?

Yes.

 

[Vintage Engine Repairs]

Hmm..

1104 is NOT rated for gasoline. I just checked the data sheet. 1184 does specifically rated for gasoline. I haven't use 1184 for fuel tank repair though.

If you check the MSDS, both products are identical.

Uses for 1104 NEO Plus which is 1184 for Australians

 

[qurotro]

If you check the MSDS, both products are identical.

Uses for 1104 NEO Plus which is 1184 for Australians

View attachment 266384

I dont think so.

 

[Vintage Engine Repairs]

I dont think so.

I do... They changed the solvents to keep within USA regulations for dangerous substances - you have California to thank for that, hence why we still get 1104 everywhere else around the world. The synthetic rubber base is the same. Some thought it was lead that was removed, but checking the MSDS, there was never lead in any. It’s the chemical thinners they have changed. This doesn’t affect the end / cured product. It specifies on the uses “Fuel pumps” and “cylinder heads” - its as “fuel resistant” as any, which means, it can withstand light fuel contact, but not immersion. Motoseal says fuel resistant too and you can see what happens to that when it’s submerged too. They aren’t designed for constant fuel contact, they’ll all soften.... in fact no gasket maker can withstand immersion, it’s why they aren’t specified to be used to fix fuel tank holes etc.

 

[qurotro]

I do... They changed the solvents to keep within USA regulations for dangerous substances - you have California to thank for that, hence why we still get 1104 everywhere else around the world. The synthetic rubber base is the same. Some thought it was lead that was removed, but checking the MSDS, there was never lead in any. It’s the chemical thinners they have changed. This doesn’t affect the end / cured product. It specifies on the uses “Fuel pumps” and “cylinder heads” - its as “fuel resistant” as any, which means, it can withstand light fuel contact, but not immersion. Motoseal says fuel resistant too and you can see what happens to that when it’s submerged too. They aren’t designed for constant fuel contact, they’ll all soften.... in fact no gasket maker can withstand immersion, it’s why they aren’t specified to be used to fix fuel tank holes etc.
View attachment 266394

The PDF of 1184 I post even show immersion temperature in gasoline... Just sayin' the PDF though. I haven't use it to fix fuel tank, so no experience.

 

[av8or3]

Aircraft fuel tank sealants are fuel proof. A “wet wing” is a wing that does not use a rubber fuel bladder. As the wing is assembled sealant is applied between layers of metal. After assembly a Type A sealant is laid across all interior joints and seams. Your wing is now the actual gas tank.
Works good, lasts a long time. (the Cessnas I work on were built nearly 50 years ago, and are still holding fuel). It can be applied incorrectly and will eventually leak, but if done properly, Uh-uh, no leaks, almost ever. If a wing should become damaged, or if a bonehead runs a screw in that’s too long. No sealant in the world can fix stupid.