Which transom seal is better-Mallory or Sierra?

Joined
May 27, 2013
Messages
22
I have an 84 Seaswirl with an OMC 800. I would like an opinion as to which is better quality.
Thanks, Andy
I am not sure if the Lund is worth repairing, but this Seaswirl is just about to get wet.
 

Nivekt

Chief Petty Officer
Joined
May 13, 2009
Messages
481
Re: Which transom seal is better-Mallory or Sierra?

Neither. Go with the GLM 86710. After 5 years, 3 of which it sat out in the sun, it is still soft and pliable like the day it was new. Here is the best price for it: OMC Stringer Transom Seal 909527
 

Redrig

Master Chief Petty Officer
Joined
Oct 13, 2009
Messages
849
Re: Which transom seal is better-Mallory or Sierra?

yeah, dont go aftermarket if at all possible. Buy that one in Howards link
 
Joined
May 27, 2013
Messages
22
Re: Which transom seal is better-Mallory or Sierra?

OK. I did not know factory parts were still available. Thanks, I am an automotive/truck mechanic by trade and always use factory parts if available. I am new to i/o power boats, had an old 62 Southwind w/ a 75 Evinrude but a tree destroyed it back in 2000. I can get factory parts from CrowleyMarine.com, has anyone done business with them? The seal is $141 with freight. And they are near Denver , I am in Oregon so it is 3 days freight.
Thanks for talking to a newby.
:D
 
Joined
May 27, 2013
Messages
22
Re: Which transom seal is better-Mallory or Sierra?

So I am going to order an oem seal. I was nervous about stretching a $140 seal over the out drive so I did a trial run with the used seal from the Lund. It appears to be an original 16 hole from 1976, it went fine. I will smooth out a few rough spots on the leading edge of the lower housing and lube the new seal well before installation. Thanks for the replies, fired the engine yesterday and it runs great on 4 year old gas. I can buy non-ethanol premium fuel here in town and plan to change the filters before it goes in the water. I need to repair the seat mounts and it will be ready to go.
:watermelon:
 

Boomyal

Supreme Mariner
Joined
Aug 16, 2003
Messages
12,072
Re: Which transom seal is better-Mallory or Sierra?

Be sure to clean the transom seal surface on the intermediate housing as well. Even though the factory installs that seal without any sealant, you might want to use a slow drying sealant on that surface when installing the new boot. Slow drying is important because you will undoubtedly end up having to rotate the boot a little to get it to line up with the screw holes in the transom. Once you get it lined up in a relaxed fashion, tighten the boot clamp on the IH housing and apply a light coating of the same sealant on the transom, around the perimeter of the boot.

Good that you are buying the OEM seal. I have heard that some aftermarket boots are very short lived. The OEM boot on my '75 is the original one and still shows no sign of checking or cracking.

btw, where are you in Oregon? I did not know you could buy non-ethanol anywhere, there. I thought that ethanol was mandated, statewide.
 
Joined
May 27, 2013
Messages
22
Re: Which transom seal is better-Mallory or Sierra?

I live in Sweet Home and there is one station in Albany, Lebanon and Sweet Home that I know of. I heard there is an exemption on premium but it is hard to find. The stations in Lebanon and Sweet Home don't have a brand name anymore and that is when they began to sell non-ethanol premium.
 

Boomyal

Supreme Mariner
Joined
Aug 16, 2003
Messages
12,072
Re: Which transom seal is better-Mallory or Sierra?

I live up in Vancouver, WA. Ethanol is not mandated here but with a few exceptions that is all you can get. I think that ethanol, being heavily subsidized, is cheaper by volume than gasoline, so that is what stations buy. We do have several places, however, that we can get regular or premium, albeit, at somewhat excessive prices.

That is all that I buy now, for all my yard implements, all the time and for the last fall fill up of my boat and old Mustang convertible.
 
Joined
May 27, 2013
Messages
22
Re: Which transom seal is better-Mallory or Sierra?

I received my genuine OMC transom seal today from Crowley Marine in Denver. I also ordered 2 quarts of OMC outdrive lube and orders over $85. come with free freight. They also discount genuine parts about 10% off list price. I ordered some 3M 5200 sealer today from NAPA, so I have more to do this weekend. The previous owner had cut the steel fuel line and installed a plastic filter. I made and installed a new steel line from the pump to the carb last night. A couple more weeks and we will go to the lake.
Thanks for your replies, Andy
 

Boomyal

Supreme Mariner
Joined
Aug 16, 2003
Messages
12,072
Re: Which transom seal is better-Mallory or Sierra?

Don't use that 5200 on your transom boot. The factories did not use a sealant. Just make sure that all your surfaces a clean and smooth. When I reinstalled my original boot after 30 years, I used a very light adhesive (GasgaCinch) on the IH rim and a bead of RTV silicone around the screw hole pattern on the transom.
 
Joined
May 27, 2013
Messages
22
Re: Which transom seal is better-Mallory or Sierra?

Ok, thanks for the tip. I am amazed how soft the new oem seal is compared to the 4 year old Chinese seal.
 
Joined
May 27, 2013
Messages
22
Re: Which transom seal is better-Mallory or Sierra?

Oem seal is installed and replaced the bilge pump today. Replaced the outdrive fluid both top and bottom. Found that there were no gaskets on the lower plugs so a trip to ACE is the Place and 4 new gaskets. Had to trim the OD on the bench grinder but all is well. Test ran it and rechecked the levels and reassembled the interior. Just waiting for new stickers, should be here by Thursday. If the weather is good next Monday is our maiden voyage. Thanks again, Andy
 

Boomyal

Supreme Mariner
Joined
Aug 16, 2003
Messages
12,072
Re: Which transom seal is better-Mallory or Sierra?

Good luck on the maiden voyage. What did you end up doing with your new seal?
 
Joined
May 27, 2013
Messages
22
Re: Which transom seal is better-Mallory or Sierra?

I removed what looked like Gaskasinch on the housing and went back dry. I removed silicone from the hull and just got the seal wet with the 5200, not a bead just wet.
 
Top