Pre combustion chamber crack advice

[8769bigred]

I’m redoing my head gasket and have one questionable pre cup. The crack extends faintly to the fire ring but does not continue. Would any one have a recommendation on if I should try and run it or find a used head to steal the cups out of?

 

[rreegg]

I’m not an expert but other comments on here say it’s not an issue unless the cracking goes beyond the fire ring. Check this thread for starters. https://www.oilburners.net/threads/cracked-valve-seats-and-pre-cups.84025/

 

[8769bigred]

@rreegg thanks for the info I did read through that thread. I just wasn’t sure about it being right next to the fire ring. I guess if it has not cracked past it yet Hopfully it will not continue. I also noticed the original head gasket had a metal ring to surround the pre cup but the new ones appear not. Here’s a photo of my old gasket

 

[DougBoy66]

I think that they are there on the new gaskets, at least fel-pro or the ones from CDD, they just are not visible. I used the CDD gaskets and I think it is incased in the gasket material. I could be wrong, it has been a while since I installed them.

 

[8769bigred]

I think that they are there on the new gaskets, at least fel-pro or the ones from CDD, they just are not visible. I used the CDD gaskets and I think it is incased in the gasket material. I could be wrong, it has been a while since I installed them.

Thanks for the thoughts! I will be using their gasket. I took some more photos with the old gasket mocked up. It’s a close call. Not sure what to do.

 

[IDIBRONCO]

It’s a close call. Not sure what to do.

Still your call, but CDD is supposed to have new ones up on their site later this month. My guess is that they'll sell out pretty quickly so keep a close eye on things if you want to buy new ones from them.

 

[8769bigred]

Still your call, but CDD is supposed to have new ones up on their site later this month. My guess is that they'll sell out pretty quickly so keep a close eye on things if you want to buy new ones from them.

Wow that would be an incredible thing for a lot of people if they could get new ones! I have a lead on some used rusty heads locally here they supposedly have very good pre cups. Will have to wait and see.

 

[MasterChiefIDI]

You can always run this by Justin's email at R&D. He builds these personally and has a wealth of knowledge. He may have precups too.

 

[8769bigred]

You can always run this by Justin's email at R&D. He builds these personally and has a wealth of knowledge. He may have precups too.

Iv been thinking about that but I have already sent a few emails to him about my turbo kit plans I wanted to run by him and have not heard back. I know he is super busy and I don’t want to bombard him! lol

 

[8769bigred]

Just wanted to update this thread with my final decision for future readers.

I got lucky and found a set of rusty heads locally here. Unsure of the condition of the heads but the pre-combustion chambers in them were great. They had cracks but were tiny and did not get to the fire ring like the one photographed in this thread.

How long would the one I was concerned about last? I'm not sure. If the future reader is in a similar situation try and find a head to steal parts off of. Or just send it and hope for the best.

I will have this truck for the rest of my life so I wanted to be 100% confident it would be good to go. If it was a work truck or farm truck, I probably would have ran it. Technically it is within the ford specification.

 

[rreegg]

Godspeed, makes sense and for a truck you’ll have forever it’s the right call IMO. Love how these trucks are the opposite of disposable