Broken Float Post Repair Update

[leonardhcross]

My last video showed my failed attempt to prepare a proper receiving hole for my new repair post. After reaching out to others in this forum, I decided to go ahead and try to epoxy the repair post into the blown out hole. I epoxied the repair post into place, braced it and let it sit for 24 hours. Then I roughed up the existing repair and applied a second coat of epoxy which I extended up the post a bit. I waited another 24 hours. It feels rigid and strong so I will continue with the carb rebuild. Here is a short video: https://www.youtube.com/watch?v=jn9FS-zY9cA

[Fred Camper]

Now that the post is firm, per haps add some JB Weld around the interface to ensure the new post does not move with vibration or ... Glad you used a nail to ensure the pins aligned. Making progress for sure.

[leonardhcross]

Now that the post is firm, per haps add some JB Weld around the interface to ensure the new post does not move with vibration or ... Glad you used a nail to ensure the pins aligned. Making progress for sure.

Hi Fred. Being relatively new to the "old motorcycle" game, I have no experience with either epoxy or JB Weld. Would adding a layer of JB Weld give me more strength than adding another coat of epoxy?

[Fred Camper]

I find that JB Weld epoxy is a good choice. It is silver in color so it appears more like metal. It sands like very hard epoxy in 24 hours. I have had good results with it when I converted the fuel pump to metal and had to close off the horn. I used a combination of JB Weld with a piece of Aluminum. Results are shown below. Not a show piece but certainly functional.

[Sidecar Bob]

JB Weld is epoxy. It's just a brand that makes average products but has very good PR. Personally, I prefer to use Devcon if I can find it and LePage if I can't.

[low-side]

Leonard - I recall that many epoxies like JB used to work in the presence of fuel 20 years ago, but they don't anymore. About 5 years ago I tried epoxying a carb post in place. I let it cure for a week and it failed very quickly. Newer fuels are pretty nasty. I wish you luck.

[Shadowjack]

I've used Devcon a long time ago, and as I recall it worked well, but I have no idea where you'd find it for sale. It was putty-like and could be built up. Normal JB Weld works well for most things, although I don't know what it's like in modern fuel, and it's pretty runny before it sets. It actually will flow out smooth.

[leonardhcross]

Leonard - I recall that many epoxies like JB used to work in the presence of fuel 20 years ago, but they don't anymore. About 5 years ago I tried epoxying a carb post in place. I let it cure for a week and it failed very quickly. Newer fuels are pretty nasty. I wish you luck.

That is a bit discouraging. I used an epoxy from Harbor Freight called HFT Epoxy Super Weld "industrial strength". I chose the "slow set" variety. I tried to check for reviews on-line. There is a lot of info but it all relates to their "quick set" product. I found nothing about how it holds up in gas. So, I'll add an additional layer of epoxy before I reassemble the carb. If, like yours, the post fails, I'll go with another type pf post repair. Thanks for your input.

[redglbx]

Len, if it were me, after you get the last layer of epoxy on and plenty of time to cure I’d fill the carb(s) with gas and let it set for a while like a week or so, then drain it out, pull the bowl off and take a close look. Better to know it’s going to fail at home on your bench than at 70mph passing an 18 wheeler.

Imho, not many epoxies are good with exposure to fuel and definitely not brake fluid ! While I was still working we used a lot of different epoxies to prototype things for testing, not many worked all that well except for the 3M 2 part stuff in grey & green that we used, it was really good, but I have not seen it for sale in normal retail, but might be on-line.

Also, I would take a close look at the packaging on the stuff you used or maybe call their “tech” line to see how they feel about fuel exposure. My.02

[Fred Camper]

I recall seeing JB Weld is good with fuel but do not recall brake fluid. I would never use epoxy on a brake part anyways but expect my tach drive to never give me an issue. Time will tell.

[Sidecar Bob]

Len, if it were me, after you get the last layer of epoxy on and plenty of time to cure I’d fill the carb(s) with gas and let it set for a while like a week or so, then drain it out, pull the bowl off and take a close look

I've been thinking about this. If you were to mix up a small blob of the epoxy and put it in a little bottle of gasoline for a week or so it would tell you just as much with a lot less effort.

If it turns out that you have to take it apart and re-do the repair look for fuel tank repair epoxy. This is one brand but others (Including JB) make similar products and if it will work on a fuel tank it should be OK in a carb.
https://www.permatex.com/products/adhes ... utty-1-oz/

[leonardhcross]

Len, if it were me, after you get the last layer of epoxy on and plenty of time to cure I’d fill the carb(s) with gas and let it set for a while like a week or so, then drain it out, pull the bowl off and take a close look

I've been thinking about this. If you were to mix up a small blob of the epoxy and put it in a little bottle of gasoline for a week or so it would tell you just as much with a lot less effort.

If it turns out that you have to take it apart and re-do the repair look for fuel tank repair epoxy. This is one brand but others (Including JB) make similar products and if it will work on a fuel tank it should be OK in a carb.
https://www.permatex.com/products/adhes ... utty-1-oz/

Well, Sidecar Bob, that sounds like a great experiment and a valuable video. I will mix up a blob, let it cure for 24 hours, then submerge it in gasoline and videotape the results. Stay tuned for the results.

[redglbx]

Great suggestion Bob

[leonardhcross]

Here are the results of my epoxy immersion test. Clearly, the epoxy has softened in ten days. Two questions for me....Will the epoxy continue to soften until it fails? What do these results imply for the use of epoxy repairs inside a float bowl? https://www.youtube.com/watch?v=w702QC4lQtM

[cfairweather]

I am trying the same test using JB Weld.

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