|
Post by keknw8 on Apr 27, 2022 11:48:19 GMT -5
on the walbro hdc-45 repair kits, when using permatex spray high tack gasket sealant, do you spray both the diaphragm & gasket (fuel pump side)? or just the gasket? and do you spray just one side of both sides?
|
|
|
Post by blythkd on Apr 27, 2022 11:55:11 GMT -5
Hmmm, I've never put any kind of gasket sealer on either. Certainly do not spray the diaphragm. I guess you could put sealer on the gasket but will likely make disassembly a bit more challenging when you want it back apart.
Are you having an issue with the carb leaking?
I'll be curious to see others' opinions on this one.
|
|
|
Post by tangobravo on Apr 27, 2022 12:07:50 GMT -5
I would never use a sealant as it would make a problem for the next disassembly/ service. Would be hard to clean off and likely result in damage to the sealing areas/beads. Of all the small engines, and vehicle carburetors I have worked on thru the years, I have never used any sealants, just the bare gaskets. Find the problem if you have a leak and replace parts as necessary.
|
|
MI Old Saw
Saw Builder
 
Searching for a couple Green & Red saws…XL-904, 870 & 875!
Posts: 166
|
Post by MI Old Saw on Apr 27, 2022 12:40:50 GMT -5
I am wondering mow if some of my more stubborn revivals were the victim of sealants. Most just pop apart, and others are a mess.
|
|
|
Post by lesorubcheek on Apr 27, 2022 16:16:29 GMT -5
Another vote for not using any sealant. I use a brass soft bristled brush to get the carb housing and covers completely clean from any old stuck on gasket material, spray 'em good with carb cleaner (unless it's one with the rubber o ring inside for the needle) and assemble.
Dan
|
|
|
Post by w30bob on Apr 27, 2022 18:32:29 GMT -5
Yeah, I'm with the group on no sealant on fuel wetted carb parts. Those surfaces should be ruler flat and the gaskets supplied in any kit should be adequate for the job without any type of sealant. On the flip side High Tack is resistant to fuel, so it would do what it's supposed to........just don't think it's needed, and as others have said...won't be fun to remove when you disassemble again.
;O)
|
|
|
Post by stillsawing on Apr 28, 2022 8:28:21 GMT -5
The factory doesn't use it, why would you?
|
|
|
Post by tangobravo on Apr 28, 2022 9:43:46 GMT -5
We would sometimes spray the float bowl and fuel block gaskets with teflon on Holley race carburetors to help remove them for jet/power valve/ float changes.
|
|
|
Post by keknw8 on Apr 29, 2022 12:02:23 GMT -5
Hmmm, I've never put any kind of gasket sealer on either. Certainly do not spray the diaphragm. I guess you could put sealer on the gasket but will likely make disassembly a bit more challenging when you want it back apart. Are you having an issue with the carb leaking? I'll be curious to see others' opinions on this one. the hdc-45 does leak pressure. i followed one of leon's vids regarding testing carb for pressure leaks. in that one he did mention he uses permatex spray sealant. and using a different bolt to fasten the cover in. that helped some but not enough.
|
|
|
Post by keknw8 on Apr 29, 2022 12:05:39 GMT -5
I would never use a sealant as it would make a problem for the next disassembly/ service. Would be hard to clean off and likely result in damage to the sealing areas/beads. Of all the small engines, and vehicle carburetors I have worked on thru the years, I have never used any sealants, just the bare gaskets. Find the problem if you have a leak and replace parts as necessary. may be just too old a carb. no matter how hard the cover gets tightened, have used diff bolts), it leaks around at least half of the cover edge using soapy water test. whether it is due to the cover edge or the carb body surface or both i can't really say.
|
|
|
Post by keknw8 on Apr 29, 2022 12:57:18 GMT -5
Another vote for not using any sealant. I use a brass soft bristled brush to get the carb housing and covers completely clean from any old stuck on gasket material, spray 'em good with carb cleaner (unless it's one with the rubber o ring inside for the needle) and assemble. Dan have done this. there wasn't much of any stuck old gasket material.
|
|
|
Post by 5terrysupersaws on Apr 29, 2022 13:35:48 GMT -5
HDC Carb pump side leaks are often caused by gasket porosity. The only remedy when others fail is to seal the gasket.
Suggest Pematex Aviation Form-A-Gasket Sealant Liquid #58931, it's well suited for this application.
It's a slow-drying, non-hardening, gasoline-resistant, sealer for gaskets and machined surfaces.
Lightly coat the gasket, let air dry for a few minutes and assemble.
I prefer it over the High Tack spray since it is not an adhesive.
|
|
|
Post by keknw8 on Apr 29, 2022 14:49:40 GMT -5
Yeah, I'm with the group on no sealant on fuel wetted carb parts. Those surfaces should be ruler flat and the gaskets supplied in any kit should be adequate for the job without any type of sealant. On the flip side High Tack is resistant to fuel, so it would do what it's supposed to........just don't think it's needed, and as others have said...won't be fun to remove when you disassemble again. ;O) the carb side (fuel pump side) appears flat using a square ruler. i'll see about taking a few images vs me trying to write out what i'm seeing. i'll get that done a little later today after service dog training.
|
|
|
Post by keknw8 on Apr 29, 2022 15:34:40 GMT -5
HDC Carb pump side leaks are often caused by gasket porosity. The only remedy when others fail is to seal the gasket. Suggest Pematex Aviation Form-A-Gasket Sealant Liquid #58931, it's well suited for this application. It's a slow-drying, non-hardening, gasoline-resistant, sealer for gaskets and machined surfaces. Lightly coat the gasket, let air dry for a few minutes and assemble. I prefer it over the High Tack spray since it is not an adhesive. might as well get a tube and give it a try at this point.
|
|
|
Post by blythkd on Apr 29, 2022 21:30:08 GMT -5
Well if Leon has done it with success, I'm in. I'd just never done it. Still livin and learnin after almost 40 years!
|
|
|
Post by onlyhomelites on Apr 30, 2022 22:40:08 GMT -5
I don't seal every one, but for persistent leaks I will use Permatex Gasket Sealant from an aerosol can. It absorbs into the gasket, dries quickly and it is not hard to remove the gasket again. As noted by folks already, never on the diaphragm itself...that wouldn't end well.
|
|
|
Post by keknw8 on May 1, 2022 13:41:39 GMT -5
Yeah, I'm with the group on no sealant on fuel wetted carb parts. Those surfaces should be ruler flat and the gaskets supplied in any kit should be adequate for the job without any type of sealant. On the flip side High Tack is resistant to fuel, so it would do what it's supposed to........just don't think it's needed, and as others have said...won't be fun to remove when you disassemble again. ;O) here's some images of the hdc-45. folks on this thread will likely see some minute imperfections. apologies for delay, life had other plans as usual...
|
|
|
Post by keknw8 on May 1, 2022 13:47:19 GMT -5
|
|
|
Post by keknw8 on May 1, 2022 13:49:57 GMT -5
<button disabled="" class="c-attachment-insert--linked o-btn--sm">Attachment Deleted</button><button disabled="" class="c-attachment-insert--linked o-btn--sm">Attachment Deleted</button> Attachments:

|
|
|
Post by keknw8 on May 1, 2022 13:53:17 GMT -5
i'm sure there is a more efficient way of uploading a handful of images to one post versus the many i posted to get some images up. should be good enough to drill in and see the carb and assess if some gasket might help in this case. tia
|
|