Head Gasket - Best 509b - Installation

psimet

Senior Member
Installing the Best 509g gasket on a rebuilt engine using the Snyder high compression head today. I have seen mixed input regarding spraying down the gasket with any sealant before installing. Any advice one way or the other?
 
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What's a Best 509B? You have a choice between 509C (copper) and 509G (graphite).

For the Best Gasket 509G Graphtite head gasket I don't use anything.

Many do, I don't. Torque the nuts in stages to 55 ft-lbs. Torque again after a heat cycle (hot/cool). Re-torque after a few more heat cycles. Repeat. Never had an issue.

I recheck the head torque while waiting for the oil to drain when changing oil. But then I am just anal.

I have never used the 509C gasket.
 
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The advice on the G that I've heard the most is:
- if the deck and the head are clean and genuinely flat, like freshly rebuilt, no sealant is needed
- if either surface has some imperfections, a spray sealant or other sealant of your choice may help keep things together
- however, if you seal the G gasket to one or both surfaces during assembly, it's basically glued there and you will have to tediously scrape off chunks of it when you disassemble
 
The advice on the G that I've heard the most is:
- if the deck and the head are clean and genuinely flat, like freshly rebuilt, no sealant is needed
- if either surface has some imperfections, a spray sealant or other sealant of your choice may help keep things together
- however, if you seal the G gasket to one or both surfaces during assembly, it's basically glued there and you will have to tediously scrape off chunks of it when you disassemble

Thank you! - Also you're in Mebane? I lived there for a short period at the turn of the century while working in Hillsborough. Best Barbeque there for sure.
 
Thank you! - Also you're in Mebane? I lived there for a short period at the turn of the century while working in Hillsborough. Best Barbeque there for sure.

It's basically unrecognizable as the same town – the pulled pork is still great though.
 
The advice on the G that I've heard the most is:
- if the deck and the head are clean and genuinely flat, like freshly rebuilt, no sealant is needed
- if either surface has some imperfections, a spray sealant or other sealant of your choice may help keep things together
- however, if you seal the G gasket to one or both surfaces during assembly, it's basically glued there and you will have to tediously scrape off chunks of it when you disassemble
Agreed. I always use copper spray on the 509G, have never had a leak even on non-freshly decked surfaces. But you're correct, it won't come apart easily and you do have to scrape it clean on both the head and the block. I find I can get under the gasket pretty easily using a razor blade scraper, followed up with a carbide scraper for touchup. I do NOT use whizzy wheels. But I will trade scraping for leaks. I start at 25 ft-lb then go up in 10 ft-lb increments to either 55 or 65, depending on my mood.
 
I am with Jay Jay on this one. I use the 509G and the copper spray gasket sealer. Works better than any other system. No leaks after many many miles. I use a final acetone wipe.
 
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A lot depends on the condition of the surfaces. Are they flat and mate within 0.002? No pits or scratches? Absolutely clean? Minor pits can be filled in with JB Weld and then sanded flat with some fine grit wet-and-dry paper wrapped around a flat file.
 
A lot depends on the condition of the surfaces. Are they flat and mate within 0.002? No pits or scratches? Absolutely clean? Minor pits can be filled in with JB Weld and then sanded flat with some fine grit wet-and-dry paper wrapped around a flat file.

THIS!!!

Absolutely flat and absolutely clean are critical, not optional with the 509G. I still use the copper spray anyway.
 
I used the 509G with the copper spray, no leaks here. Make sure the gasket fits over the head studs easily because once sprayed every little touch wants to pull the copper off. I wait and put the 2 water outlet studs in after the head is on.
 
A lot depends on the condition of the surfaces. Are they flat and mate within 0.002? No pits or scratches? Absolutely clean? Minor pits can be filled in with JB Weld and then sanded flat with some fine grit wet-and-dry paper wrapped around a flat file.

I would use HighHeat epoxy putty rather than standard JB Weld, which is designed to work as an adhesive, but otherwise yes.

https://www.jbweld.com/product/highheat-epoxy-putty
 
I just pulled my car's head, after following the procedure in post #10 in 2020, after pulling all the studs, it lifted with a few taps in the water pump hole. Easiest ever! I had put Neversieze on the studs, which helped. The block and head will need scraping, though.
 
I installed the copper version a few months ago. I used copper spray and it is working fine. The key is to do multiple torques over a couple of weeks after repeated warming and cooling phases. Be sure not to get the spray on your head or block or you will be scraping it off after it dries. Even then it leaves traces that will make you want to re-paint.
 
I also use copper spray on the Best Head Gasket Graphite. I hang the Gasket and spray it. After spraying, give it a few minutes hanging until the spray becomes tacky. Never had one leak...
 
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