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permatex or loctite to seal crank case halfs???

D

dalefan4lyf

Member
Putting a 1995 elpto 40 hp back together after a rebuild. Book calls for loctite master gasket sealant. Can`t find it local. I have used permatex for years on cars and jeeps with few issues. Anybody else have an opinion? Thanks!!
 
You must use the correct stuff here.------------A sealer with too much " filler " , will not squeeze out properly to get the metal to metal joint.----------If this part of the job is not done correctly you will end up with loose bearings and loose reed blocks.-------The motor will not be happy !!------------Be patient and get the correct stuff ( BRP " gel seal " or Loctite 518 ) or be prepared to do the job again !!---------Some folks do not have the time to do it right the first time , but always find the time to do it twice.
 
I've used the OMC sealer stuff for years with no problem. (It resembles the brownish Permatex.) Upon pulling the motors down I see a nice seal coat on the halves every time.

Jeff
 
I have measured the seal film on some parts motors to be 0.008"-------------Means that the mechanic who put it together had no idea of what he was doing / working on.
 
I used the gel on my crank case. From what I understand, it only sets up in the absense of air, like between the torqued down case halves. Anything that squeezes out into the motor remains liquid; meaning no chunks inside the motor.
 
Meticulous preparation of these surfaces is important and so is the correct sealer.-----------------If the phone rings during this assembly just ignore it.----If somebody knocks on the door , then yell at them to come back in 15 minutes.-A 1/16" diameter bead of sealer does the job.------
 
Only use the loctite 518 sealer and use the primer/activator as this will increase cure time and strength. The primer /activator is the only thing that will cause 518 to harden outside a flange. You have about 30 mins to assemble it before it starts setting up and it is fully cured in 6hrs vs 72 hr on just 518 alone.
 
Why bother with that expensive, potentally harmful stuff when Permatex brown does the job just fine? OMC built millions of motors with it.

Jeff
 
UPDATE - Used Loctite 515. 1/16th bead and torqued in 13 minutes. Got a good "sqish" all around. The guy I got it from said that the only difference in 515 from 518 is cure time. I need to let it sit for at least 48 hours. So I am off like a heard of turtles.....
 
Jeff,
Is that what OMC really used on their assemblies? I,ve used it for gasket sealer, but I really like it on threads. It makes disassembly nice.
 
..."Is that what OMC really used on their assemblies?"

I believe so. I bought it at an OMC dealer and it lists assembly as its use on the can.

Jeff
 
OMC / BRP ----Gel seal is the stuff to use on the crankcase joints.------------Used in the proper amount it comes to about 87 cents / motor.---------Cheap if I must say so.------------Motors come apart easy too, no hammer required.
 
"Is that what OMC really used on their assemblies?"
Click to expand...
The only engines that used the "peanut butter" sealer had spaghetti seals that sealed the crankcase halfs and before Gel seal you used Adhesive "M"...
 
Loctite Master Gasket is in fact Loctite 518. Due to the presence of copper in the aluminum used for outboard motors, it wouldn't be recommended to substitute the 518. It is designed to be slower curing which allows time for assembly. A product like Loctite 515 would cure too quickly and possibly shim the parts.

Unlike the solvent based gasket sealants, the anaerobic gasketing products like 518 cure to a chemically resistant thermoset plastic which is also easily disassembled. Clean surfaces are always recommended no matter what sealant you are using. An organic solvent like alcohol which evaporates away without leaving a residue is a good choice. Excess product that is squeezed out will not cure and can be wiped away.
 
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