Best Intake BBC gaskets with Merlin Intake?
 

What are the best intake gaskets to use on merlin intake on a 502. Merlin intake was brass lined coolant ports. Thought i read on here that one brand didnt seal good on the merlin intakes, but cant find it.

I would not use the Felpro gasket # recommended by Merlin - the water passage openings are larger than the brass inlay on the intake so the aluminum gets exposed. This isn't a problem for freshwater boaters but I ended up with a waterlogged engine.

Last time I took the manifold to the shop and picked out a Mr Gasket that fit better. I did not look at the Merc gaskets.. If someone else doesn't chime in with a part number I will call the shop here and find out..

Rick

cool, i knew i read something on here about the brass not being covered by gasket but wasn't sure. I just dont want to have to order a bunch of gaskets, on cars i always use a little RTV to make them seal better on the coolant passage ways...is that a good idea on boats too.

The RTV won't hurt but make sure you lay your gasket over the manifold and make sure it fits correctly. If salt gets access to the aluminum your sealing surface will be changing for sure. And yes, I flushed my engine thoroughly after each use but salt eats through cast aluminum like a fork thru melted butter for lobster. :)

Cant find any info on Mr gasket making marine gaskets for the 502 BBC. Are they just reg auto intake gaskets, i know felpro has the marine line. Went to summitracing....do you have part numbers..

thanks

Mr. Gasket Ultra Seal with the red seal rings are my favorite and they have a fairly small water passage opening. I use RTV around the water ports and even 5200 believe it or not!

My least favorite of intake gaskets are the felpro... I've seen and also had a few squish into the intake ports and one time slipped out of place and filled an engine up with water.

Surface contact area on the Mr. G. is a lot bigger!

So the mr gasket ones are just ultra seal, there not labeled marine use or anything right.....5200 isnt that below whater line sealant

when you go th the mr gasket web sit the only gaskets they list for a 2000 502 is 4672G and so i looked in summitracing and its the ultra seal III will they work just as good. 2.00 x 1.75 thats the large rec. port size right

I wanna say I was using the 5828 but I'm not 100% sure. Mr. G doesn't designate a marine intake gasket that I know of but the nitrile fiber is very good. And yes, 5200, Dean Gellner taught me that trick!

I found one in the garage- Mr Gasket Ultraseal #5828, like the others mentioned it is an automotive part and has the most material around the water port.

Rick

You must have a gen 4......All they list for gen 5, 6 is the ultra III gakets number 4672G I wonder if its just as good... So befor they just came out with the ultra III what gasket number were the gen 5, 6 502 people using???

I have a Gen V 502 and used the Ultra 5828, number is for a Mark IV but it fits. Your local speedshop should have a couple to compare.. maybe Mr Gasket has a customer service number that could help. If not might have to buy one ultra and ultra III and see which fits best on the intake side, might not be able to use one of the $25 gaskets but that is cheaper than having it leak.

Rick

cylinder heads and lifter valley are the same on all these blocks whether they are IV, V or VI... The thing you need to pay attention to is the port size and thickness... NOt sure why they list that for a 2000 only unless there was a funky intake during that period...

We use the the Merlin intake but with re-worked ports. This cut to fit gasket is a good solution.
http://www.summitracing.com/parts/FPP-1251/

My Mr.gasket ultras came today, the rubber rings dont fully seat on the brass, it touches the aluminum in a few places......i think the felpro ones may be worse from what people are saying so, what to do.......engine builders must run into this all the time...or do u think they just toss a gasket on and dont worry. if i rtv the **** out of the ports you think i will be ok?? Makes me nervous as its a brand new crate motor.

mr gasket ultra III got them today real nice gasket small water ports

joepequa can u do me a big favor....can u measure the excact size of the rubber oring that go around the coolant ports. the ultra 1 gaskets almost make it, but cover some of the aluminum, i want the rubber orings to only touch the brass.

I will check tomorrow , I had the same problem had the felpro 1275 , the ultra III real nice not the ultra I or II .

have you installed the merlin intake before....and it leaked?? Or are you tring to finf the right ones before the install? The way that merlin cast the intake they didnt do a good job lineing up the brass ports in the middle of the bolts so it off set a bit and not tall enough......real small ports gaskets would be great... thanks

whats the part number you are using for the ultra 3's?

i have dart intakes with dart alum heads not the brass linner ,the mr gasket ultra III part # 4675g, I also got the felpro 1275S-3 is a real nice gasket,not the standard 1275, that is garbage.Go to jegs on linethey have real good pics,check out the water ports on the 1275S-3

Maybe I'm mistaken, does the 4675g not have the sealant rings on the gasket but the gasket itself cellulose/nitrate?

felpro 4675s-3 has no rings,it does have a steel core .

MY MISTAKE NOT FELPRO. mr gasket 4675g has no rings .