The Hanes manual says that when you rebuild an engine you need a sealant to put on the housings. It never makes any mention of what the sealant actually is though. If anyone could help me out with this it would be great, I really want to get my engine back in the car. It's been too long since I drove it!

 

Most people use and reccommend hylomar. I used it 2 months ago and it turned out great! i suppose a sillicone based sealant would work too, but hylomar is the way to go!

 

Thanks a lot!

 

The seals themselves do the actual sealing, the hylomar keeps them in place during assembly. Do not use vasoline on the black coolant seals, they will swell, grow and not fit.

 

Get the RotaryAviation.com rebuild video. I used it on my first (and only so far) rebuild and it was invaluable. He tells you what to use. I'm pretty sure it was Hylomar on the housings, but you should check out the video to be sure.

Rich

 

I'm suprised no one has pointed this out but you also need a good silicone sealant like Ultra Black on the legs of the housings. This is to stop oil seepage out of the sump when it sloshes around. Hylomar is only used to keep the coolant seals in place during assembly. Mazda recommends using vaseline.

 

Definitely pick up the DVD. It is well worth the 25 bucks...

 

I can never understand those who use and recommend Hylomar. Yes, it is some sticky smurf snot, but that is also why is not a good idea to use. The stuff is Hell to clean up and rather expensive. You don't need anything remotey like that. The seals just need to stay in place long enough for you to assemble the engine. We use Crisco. The consistency makes it perfect for hydrolicing the seals in place -- all of them, including water seals, side seals, corner seals, apex seals -- and what is left over acts as a great assembly lube. You just spoon it into a large syringe and squirt it into every groove. When you press the seals in place, they are held by hydrolic suction. No muss no fuss. And when you need to get back in there to freshen up the engine, you are not faced with a nasty, sticky, blue smurf snot sandwich to clean up.

For the "legs", any quality RTV Silicone will work. We usually use Permatex Ultra Black or Ultra Red. Hondabond (don't laugh!) is also excellent...if we could get it in a pressurized can, we'd still use it.

 

Thanks a lot guys. You've all been a big help. Unfortunately I smashed two of the seals so I'm waiting for new ones. Won't make that mistake a second time. The crisco sounds great but I'm also wondering why you wouldn't use Vasoline especially if it's just to keep the seals in place during asembly. The seals that didn't have much (or any) vasoline on are the ones that fell out and the ones that did stayed right where they were supposed to. Now I'm just hoping the rest of them don't swell while I wait a couple days for new ones.

 

Vasoline makes the rubber seals swell, then they will not fit, nor stay in place. That is why I switched to Hylomar. For me, Hylomar is cheap insurance that the seals will stay put.

Bet the new seals cost more than a tube of Hylomar.

Now as far as the hard seals go, Vasoline works fine.

 

Simple: the Crisco is better. Hands down. It works for ALL the seals, holds them in place better and is a great assembly lube to boot. When Mazda trained Rob Golden to rebuild engines back in the 80s, they used Crisco; not Vasoline. Rob's been using it ever since on hundreds and hundreds of motors. Hylomar might work but it is too nasty and has NO advantages (unless you count pissing off the next guy who rebuilds the engine).

 

I agree. I've used Hylomar and it makes an awful mess when you disassemble the engine. Stick to what Mazda recommends.