Best crankcase sealant for McCulloch Pro Mac 610?

[alieder54656]

What works best (and lasts the longest) for sealing the crankcase halves on a McCulloch Pro Mac 610? The factory originally sealed it with Dow Corning Silastic 732 Multipurpose Silicone RTV Sealant, which didn't appear to hold up very well (especially on the bar oil tank which always left a nice puddle of sticky oil on the floor ), and like most silicone rtv sealants is not gasoline resistant. Therefore I don't want to use any silicone rtv sealants for this. I have experimented a bit with Permatex MotoSeal 1 Gray (a solvent curing synthetic rubber gasket maker which is fuel resistant, and designed for two stroke engines), which may be a good sealer for larger engines (like a kart or outbaord), but for this job it is way too messy, too easy to over apply (don't want this stuff getting into the engine & bearings :x ), and simply just a big PITA too work with (at least for me and my low patience for pudder jobs) :bang: . Also I notice it can be peeled off pretty easy (since it is also designed for frequently disassembled engines) and may not hold up in the long term.

I then noticed that in the late eighties McCulloch stopped recommending using Dow Corning silicone rtv sealant, and started recommending Loctite 518, which is a anaerobic (cures in the absence of air) gel form-in-place gasket maker designed for sealing close fitting joints between rigid metal surfaces. This sounds like it would be good stuff and easy to apply. And if any uncured gel were to get into the engine it is supposed to harmlessly flush out and burn up with the fuel mix.

So now I am debating between getting Loctite 518/Permatex Anaerobic Gasket Maker (same stuff still licensed to ITW Permatex by Henkle Loctite since Permatex's part number for it is 51813), or otherwise using the Permatex Motoseal (that I already bought, opened, and can't return :doh: ).
Here are some links to their tech. sheets:
-Loctite 518: http://tds.loctite.com/tds5/docs/518-EN.pdf
-Permatex Anaerobic Gasket Maker: http://www.permatex.com/documents/tds/Automotive/51813.pdf
-Permatex MotoSeal 1 Ultimate Gasket Maker Gray: http://www.permatex.com/documents/tds/Automotive/29132.pdf

Has anybody tried and had good luck with the anaerobic gasket makers and recommend them for this application?

 

[bigbadbob]

Welcome to AS.
I use a some stuff called 'The Right Stuff' comes in a pressurised can.
I used it on a GM oil pan, it was all I colud do to get it off a few days later, have used it on lots of other stuff too.
It is apperently what OEM car plants use. Not cheap $20 for a small can.
Have never had it leak!!

 

[poulson01]

I've always used Indian Head. I'm sure there's some reason no one else uses it but it has always worked for me.

 

[Metals406]

Welcome to AS.
I use a some stuff called 'The Right Stuff' comes in a pressurised can.
I used it on a GM oil pan, it was all I colud do to get it off a few days later, have used it on lots of other stuff too.
It is apperently what OEM car plants use. Not cheap $20 for a small can.
Have never had it leak!!

I love The Right Stuff. . . But I'm pretty sure it isn't fuel and alcohol resistant. Threebond 1194 is fuel resistant, not sure about alcohol though? This ethanol fuel we get now adds another hitch in the rope.

 

[alieder54656]

I love The Right Stuff. . . But I'm pretty sure it isn't fuel and alcohol resistant. Threebond 1194 is fuel resistant, not sure about alcohol though? This ethanol fuel we get now adds another hitch in the rope.

Your right, The Right stuff is not fuel resistant. From what I've read, the Threebond is similar to Permatex Motoseal, which I would like to avoid as it is too messy to work with.

Has anybody used Loctite 518 Gasket Eliminator with good results and would recommend it over Permatex Motoseal for my application?

Or should I stick with the messy Motoseal, which I already have?

Thanks.

 

[redunshee]

Dirko HT is the way to go. Best stuff I've ever used. My Stihl dealer evenuses it.

 

[beavis331]

alieder if you do a search on this site you will find a wealth of information on sealers. The subject comes up every so often. The general consensus is not to use a silicone type sealer. That being said there is a wide variety of sealers that guys on here use. One of the most populer is threebond 1194 as stated by metals. I believe this is the same as yamabond. There is also a large following that use the anaerobic type sealers like you are talking about. I personally use the threebond 1194. But I would not hesitate to use the anaerobic stuff as a lot of people have had luck with it.

 

[alieder54656]

Okay I think I will try the anaerobic Loctite 518 to seal the crankcase, since nobody said they had any problems with it .

Will Loctite 518 work well on the bar oil tank? The bar oil tank was also sealed at the factory with Dow Corning Silastic 732 Silicone RTV Sealant, and most Pro Mac 610's (including mine) all start to leak after a while and leave a nice puddle of oil on the floor :censored:. Can Loctite 518 be used to seal this, or would there be too much vibration and flexing to use an anaerobic gasket here? The mounting surfaces are rigid and machined but, the are no edge flanges to hold it firmly from sliding and twisting (not enough to see with the naked eye but maybe enough to microscopiclly shear the anaerobic seal?). All that holds the tank in positition are four bolts (unlike the crankcase halves which are firmly held in place by the crankshaft bearings and the bolts mainly hold it together tight). Any thoughts?

 

[beavis331]

I can't imagine you having any trouble with the oil resevoir.

 

[alieder54656]

I can't imagine you having any trouble with the oil resevoir.

Well, it leaked for many years while my uncle used it as his firewood saw.

This saw kind of has some sentimental value to me. It sort of killed my grandpa. Back in December 1993 my grandpa was out in the woods cutting firewood all day and came back late at night. My grandpa had heart problems all his life and my grandma always told him she didn't like him going staying out there all day long by himself but he was kind of bull headed and didn't care if she liked it or not; he wanted to cut firewood! Anyway, that particular day when he got home he was sitting at the kitchen table talking to my grandma. He called over their dog to the table to pet it and then just slumped over (he had a heart attack and went unconscious). My uncle rushed over and started to give him CPR. He lived for a couple weeks but didn't seem to remember anyone or know anything or talk. He died December 28. Using this saw was just too much for him and just wore out his bad heart. But, he didn't like anybody else using his saw :chainsawguy:.

Then my uncle used it until 2008 it wore out (it could have lasted years longer if he would have done proper maintinence such as cleaning the sawdust out of the cooling fins, clean the carbon out of the exhaust port, etc.). It was a damn good saw (1980-2008, now 2010-??)!

So I would like to rebuild it to be like it was when it was new (or better) and I'm really fussy about everything I do :hmm3grin2orange:.

Aaron

 

[Hamsta44]

I always use Yamabond. Never had a failure in 25 yrs.

 

[Jack Letby]

Best Crankcase Sealant for McCulloch Pro Mac 610 Chainsaw.

Hello alieder 54656.
Referring to your Crankcase Oil Tank Sealant posted 13-03-2010 many thanks for your article.

I used the "Permatex Anerobic Gasket Maker" in a 50 ml tube successfully to reseal the joints to three (3) Pro Mac 610 Chainsaws that I have just rebuilt, with no sign of an oil leak, thank you.

Also I"m looking for contact information, where in the USA can source spare parts for the Pro Mac 610's and Eager Beaver 3.7's please, nothing available in Australia.

All the best, much appreciated.
Jack Letby. (Sydney)