exhaust cross over (heat riser) fill - Page 3

MoonlightGraham · 10-09-2013, 01:21 AM

Quote:

Originally Posted by Mike Taylor 3601

Ron,
I use zinc alloy get from Mc Master Carr supply ,it's the same thing Mondello use to sell.
I melt enough into a steel cup I made from tubing and flat bar w/flat bar long enough to also be handle to pick up and pour with,I usaully block @ intake side and pour from bowl side have to use some sort of funnel some times.
The zinc will probaly out last the heads.
Mike Taylor 3601

Sorry to bring up an old thread but I was wondering how much zinc you needed to do this procedure?

This is what I found on McMaster-Carr's website:

http://www.mcmaster.com/#zinc-alloys/=outleo

Great info guys! Thank you

Mike Taylor 3601 · 10-09-2013, 08:17 AM

I usaully buy the 4 1/2 lbs. bar 9069K2. depending on what type of heads you are working sbc can do 2-3 sets.
Have also filled intakes that are cracked in heat cross over area,just fill it up does'nt matter then.
Mike Taylor 3601

Kevin Panzino · 10-09-2013, 08:37 AM

Interesting... I used the exact same Zinc material/part # from McMaster (9069K2) and when I pulled the heads after about 50 passes, I found the material melted back pretty bad in the port area.

Granted, I know it says it melts at 792°F, but I saw others using it with success, and figured there would be enough heat transfer into the head casting to keep it from melting...

Was going to use Aluminum next time (melting point ~1,220°F)....

No one else has melted the Zinc ???

MoonlightGraham · 10-09-2013, 12:03 PM

Quote:

Originally Posted by Mike Taylor 3601

I usaully buy the 4 1/2 lbs. bar 9069K2. depending on what type of heads you are working sbc can do 2-3 sets.
Have also filled intakes that are cracked in heat cross over area,just fill it up does'nt matter then.
Mike Taylor 3601

Thank you for the information

Mike Taylor 3601 · 10-10-2013, 08:41 AM

I have'nt had any problems that I know of with it melting out of head,I will tearing into one that was done about 200 passes ago will let you know how it looks.

I wonder how consistent melting point is? I have noticed some of the bars seem to melt easier,but I could just be less patient that day.
Mike Taylor 3601

10-09-2013, 08:17 AM	#22
Mike Taylor 3601 VIP Member Join Date: Oct 2008 Location: Somerset,Ky Posts: 1,303 Likes: 198 Liked 116 Times in 48 Posts	Re: exhaust cross over (heat riser) fill I usaully buy the 4 1/2 lbs. bar 9069K2. depending on what type of heads you are working sbc can do 2-3 sets. Have also filled intakes that are cracked in heat cross over area,just fill it up does'nt matter then. Mike Taylor 3601

10-09-2013, 08:37 AM	#23
Kevin Panzino Senior Member Join Date: Oct 2002 Location: Pittsburgh Posts: 532 Likes: 257 Liked 599 Times in 113 Posts	Re: exhaust cross over (heat riser) fill Interesting... I used the exact same Zinc material/part # from McMaster (9069K2) and when I pulled the heads after about 50 passes, I found the material melted back pretty bad in the port area. Granted, I know it says it melts at 792°F, but I saw others using it with success, and figured there would be enough heat transfer into the head casting to keep it from melting... Was going to use Aluminum next time (melting point ~1,220°F).... No one else has melted the Zinc ???

10-10-2013, 08:41 AM	#25
Mike Taylor 3601 VIP Member Join Date: Oct 2008 Location: Somerset,Ky Posts: 1,303 Likes: 198 Liked 116 Times in 48 Posts	Re: exhaust cross over (heat riser) fill I have'nt had any problems that I know of with it melting out of head,I will tearing into one that was done about 200 passes ago will let you know how it looks. I wonder how consistent melting point is? I have noticed some of the bars seem to melt easier,but I could just be less patient that day. Mike Taylor 3601