Problems with Best brand head gaskets.

Mart

Mart

Well-known member
I've just suffered a second head gasket failure on the big bore motor in my 32 sedan. The first one failed a couple of years ago coincidental with a thermostat failure.
The other one has failed in a similar way with no other contributing factor.
The failure is due to the material in the centre of the gasket extruding out the side of the gasket. The material is a plasticky material. Once it goes soft the head bolts lose their torque.
I replaced them with FelPro gaskets. The intermediate material in the Felpro has a metal mesh inside the filler material. It is far superior.

Pictures show the extruded intermediate material and the felpro intermediate material with the metal mesh inside.
 

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Mart said:
I've just suffered a second head gasket failure on the big bore motor in my 32 sedan. The first one failed a couple of years ago coincidental with a thermostat failure.
The other one has failed in a similar way with no other contributing factor.
The failure is due to the material in the centre of the gasket extruding out the side of the gasket. The material is a plasticky material. Once it goes soft the head bolts lose their torque.
I replaced them with FelPro gaskets. The intermediate material in the Felpro has a metal mesh inside the filler material. It is far superior.

Pictures show the extruded intermediate material and the felpro intermediate material with the metal mesh inside.
Click to expand...
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Wow. Used two sets of copper Best big bore gaskets without issue. Will keep an eye on them after seeing this.
 
Same happened to me on my french engine with Edelbrock heads and the same Best gaskets. I built another engine, this time with a blower, and used the greased french gaskets with another pair of Edelbrocks.For the last 6000 km no problems despite up to 10 psi blower pressure.
 
On a related note, I have been saying for a long time that if you have to use a sealant on your head gaskets, there is something not right with the surface preparation. If you need more than grease, somethings not flat or the surface has a problem.
 
Anyone know the Fel-Pro part number for big bore 39-48 copper head gaskets?
I have a Best gasket kit with the same gaskets that failed on Mart's engine and prefer to get different head gaskets now.
 
I've had problems with Best brand valley cover gaskets; they are grey cardboard type material and they de laminate and separate. Now using Felpro; they have a metallic layer sandwiched in the middle.
 
Tony said:
Summit has the Fel-Pro. https://www.summitracing.com/parts/...k0l7cqu8DUWsBbSvQweCwh2rxeJCdegYaAktBEALw_wcB
I see that Speedway sells what looks like solid copper gaskets.
https://www.speedwaymotors.com/1939-48-Flathead-Big-Bore-Head-Gaskets-Copper,4409.html
Click to expand...
I found the 8BA era Fel-Pro gaskets on Summit, and may end up buying two and trimming like Mart did. I would prefer 39-48 style if they are still available.
I looked at the Speedway gaskets, and zoomed in on the picture posted in their ebay add for the same gasket set. The picture looks like it has a Best stamp in it, like Speedway is packaging Best head gaskets.
 
I find this very interesting. Oddly, a noted YBlock engine builder prefers the Best gaskets over the Fel-Pro., saying he has had leakage problems with the Fel-Pro.
 
tubman said:
On a related note, I have been saying for a long time that if you have to use a sealant on your head gaskets, there is something not right with the surface preparation. If you need more than grease, somethings not flat or the surface has a problem.
Click to expand...

I agree with the Felpro Gaskets. Do not use anything on them since they already have a coating that heats up and makes the seal. I used Felpro gaskets at work on all kinds of engines and I've never had one fail. Just make sure the surfaces are straight and clean and torque them evenly, run the engine umtil it gets warm. Let it cool down and then retorque the heads. This important, run antifreeze to protect your cooling system and gaskets from rusting. I keep running across people using straight water, their nuts. Once rust starts you will never get it out of the passages, antifreeze prevents the rust. Twenty-year-old coolant/antifreeze passages look brand new if the coolant is changed regularly. It's one of the best investments you can make for your engine.

Check your local parts store, if they can order the Felpro flathead gaskets which they should be able to do, it will save you on the shipping. See if they can match the price of any mail order ones you find for sale.

I would "not run" a tap down the head bolt threads. I read that Ford used an interference thread design on the flathead to make the threads seal, since 46 out of the 48 passages go clean through to the coolant. If you tap the block, you can change the interference thread, and it will leak. even with sealant. I learned that lesson the hard way on my first flathead. Now I just clean the block threads, but I won't run a tap down them. A neighbor who is a retired Nasa machinist built a flathead, and he ran a tap into every single block thread on a 59A and every single head stud but two leaked with sealer, and this was meticulous guy. There's not much talk about this interference head thread on the flatheads but I'm pretty sure there's something to that. Somewhere there is a factory video the shows a guy running studs into a block on the assembly line. It's to see but can't see any thread sealant, that makes me think the interference thread story is correct.
 
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I'm an "8BA guy", so I use an extra Ford head bolt with some grooves filed in it to chase the threads.
 
That looks really weird. I can’t imagine a properly built head gasket turns to “goo” between the metal. I’ve heard of quality issues with some of Felpro products, but Nick from Nick’s Garage swears by them and uses them exclusively in all his engine builds. I have Felpro on my flathead.
 
I have Cometic MLS gaskets on my 284 cubic inch flatty in my cabriolet. The only Best gaskets I've used in recent years are the composite ones - have not had any issues with them.
 
Two builds with Fel-pro, no problems. First one was done in the 90s and the present owner has put many miles that car .
 
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