CDL gallone bottles leaking

[Bricklayer]

Once again I’ve come across this issue. This time I actually have syrup going moldy in the bottles. Different supplier this time but I’m assuming they all get their bottles from the same manufacturer.
I’ve been bottling them same way.

-Syrup at 185 even double and triple checked with different thermometers
- Fill bottle to just under the threads. Leaves about 1/2” to top of bottle open
- place cap on and tighten.
- turn bottle on side for 10 minutes then stand up.

Had no problem at all in 2020 and 2021. But now it’s back.

Called the supplier and they asked me if I was placing bottle on its side after installing cap. I said yes of course.
They said that I should not do that. And that’s why I’m getting leaks and not getting a proper seal. The temperature of the syrup is overheating the cap material. Was told to fill bottle to within 1/4” of top and place cap on and done.

#1. Ontario regulations for hotpacking syrup states that I have to turn bottle on its side and recommends preheating the bottles.
#2. Why is a maple equipment company selling a maple bottle and cap that is not suitable for temperatures to be able to hot pack syrup.

[Sugar Bear]

90% of my gallone 1litre bottles are leaking. Been using the same bottles for 3 years and only had the odd one leak.
Tried going to a different manufacturer to try different lids. Same thing happened.
Tried different bottling techniques like not heating up bottles first. That didn’t work. Tried putting bottles on side for different amounts of time that didn’t work. Tried giving the caps a tighten once cooled down a bit. That didn’t work either. Driving me insane. Got 100 litres bottled and more to do and don’t want to sell leaking bottles.
CDL has said nobody else is having problems. Find that hard to believe.
Anybody else having issues.
Attachment 20017

I have been using the glass 12 ounce and 8 ounce bottles for some years now. Over the years I have had occasional leaking bottles. This year I had 5 bottles. Until this year I always thought it was the cap not on correctly or tight enough. Finally this year I determined and verified that these leaks ( at least all 5 of them this year ) were caused by barely visible hairline short cracks of about 1/4 inch r less just below the threads on the neck of the bottle. Because these cracks are so close to the threads in makes it appear that it is leaking from the cap when the bottle is upside down. BUT IT IS NOT AND LEAKS FROM THE CRACK. Not sure how the cracks got there.

I suggest you take a magnifying glass and look for hairline cracks on your bottles in the neck area at or just below the threads.

My conjectured thoughts on possible causes of the cracks.

1) The glass in the necks is more prone to cracking in that area from its compounded curving in that area when the hot syrup hits it for a while ( I.E. the Pyrex/Low Thermal Expansion cannot function as well in the neck area of a bottle ) . I will try to verify this case by observing bottles before filling with hot syrup and trying to catch a crack in the act post hot syrup fill up.

2) Bottles are stored upside down and if they are dropped on their necks with any level of drop, they may perhaps crack their necks, kind of like yours or mine would.

3) MBF otherwise known as Manufacturing Brain Fart. (all cracks are small and in the same area of the bottle, but some look different than others)

When I can locate my macro lens amongst all my junk (could be six years from now) I will photo and post the cracks.

So, it's hard to believe, but the smallest hairline crack in a bottle, even a barely visible one, can leak MUCH quicker then you will expect. Verified it with the old peepers this year for sure!

[DRoseum]

I have had these leaking issues with the 1000ml gallone bottles as well. Easy to over tighten cap and it leaks. Cap gets soft from hot syrup and it leaks. I think the thread engagement length and material of the cap are problematic. Really love the look of these bottles but the caps are VERY annoying. I had SLIGHTLY better luck with the golden caps with the tamper evident ring. They came in an order thru bascoms early this year (unprinted 1000ml stock). I found just barely tight enough and on side but slightly elevating the bottle neck/cap helped.