Adrian Smith 1 Posted February 13, 2015 Share Posted February 13, 2015 the Walbro carby on my OS 60 GT annoyingly has plastic fuel inlet nozzles and in the process of pushing Tygon tubing on the the nozzle, the nozzle snapped! I am certain that it won' t be able to be cynoed back together unless anybody knows better. I assume the nozzle is a screw fit and wonder if I can source a new nozzle from somewhere, as I don't want to source another carby assuming that I can even find one that fits. Any ideas? I feel a bit stupid as you can imagine! Quote Link to comment Share on other sites More sharing options...
Merlin spit Posted February 13, 2015 Share Posted February 13, 2015 **LINK** not instock but gives part numbers so hopfully some where like **LINK** will help you out .it is possible to get a all metal part from them to. The brass part of the old one needs a twist with pliers /grips and a dab of epoxy on the new one as it pressed in job done.not sure how i got this knowledge Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted February 13, 2015 Author Share Posted February 13, 2015 thanks Austenrover that's a start for me to investigate. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted February 14, 2015 Author Share Posted February 14, 2015 I think I may approach this a different way. The nipple I have broken is actually the pulse inlet which is set in the fuel pump diaphragm cover which is secured with one screw. Its an Walbro HDA 313 carby. Given that the inlet looks like a push in fit am am thinking I will remove the cover and warm is slightly and see if I can pull it out. As the item appears to be a metal tube/plastic composite I was wondering whether I can find some same gauge brass tube, bend a piece with my little pipe benders to form the nozzle and push fit the other end into the plate. If need be I can solder a fuel barb onto it to secure the Tygon tube. After all some Walbro carbys have inlet & outlet nozzles that are formed liked that, not with plastic. mmrmodeltech.com do the composite walbro carby inlet and outlet fittings but no dimensions are posted so I don't know if they are standard fitting. Quote Link to comment Share on other sites More sharing options...
john melia 1 Posted February 14, 2015 Share Posted February 14, 2015 now if like me you buy a fake walbro carb , it has metal fuel inlet tube , instead of the cheap black plastic , see nowt wrong with fakes lol Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted February 14, 2015 Author Share Posted February 14, 2015 Ok so here is the problem to be sorted. I unscrewed the fuel pump diaphragm pump cover and as you can see the gaskets left in situ. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted February 14, 2015 Author Share Posted February 14, 2015 Turning the cover over it can be seem where the inlet pipe sits. I duly heated to cover gently with a heat gun and a couple of sharp taps with a slightly undersize piece of brass pipe and the whole nozzle came free. I measured the pipe diameter with my digital calipers and it looks to be 3.99mm or 5/32" in old money. I have ordered some brass pipe from RC World UK and for the sake of overkill a couple of Walbro carb inlet nozzles to see if they will fit. Watch this space. Edited By Adrian Smith 1 on 14/02/2015 15:24:16 Quote Link to comment Share on other sites More sharing options...
Shaunie Posted February 14, 2015 Share Posted February 14, 2015 What I have done in the past (many times) is to press a piece of brass tube up the inside of the broken section. You may need to use an appropriate adhesive but remember that epoxy resin is not petrol resistant! Shaunie. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted February 14, 2015 Author Share Posted February 14, 2015 Well if it comes to it I will use some high temperature silicone sealant as a start, but I think it will be a tight fit Shaunie anyway. Quote Link to comment Share on other sites More sharing options...
Shaunie Posted February 14, 2015 Share Posted February 14, 2015 If you're pushing a piece of pipe straight into the cover then you will have no problems. My method is to join the two parts of a broken spigot. Don't think silicone sealer is that good on petrol either. Wurth (or other brands) pipe seal works well, this is a methacrylate based product. Granville Petropatch available from motor spare places in completely petrol proof, it's a bit like the good old "red lead" pipe jointing compound. In you case it's not directly in petrol anyway so you should have no problems. Good luck. Oh, and dip your pipes in boiling water before pushing them on and they will be more pliable. Shaunie. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted February 15, 2015 Author Share Posted February 15, 2015 Good advice Shaunie thanks mate. I will be pushing a pipe straight into the cover as you say and I with give some heat to both parts and cross my fingers. I don't think it comes into contact with fuel as such as it seems to provide some sort of pressure from the crank case to the fuel diaphragm pump. But then I am no expert. Quote Link to comment Share on other sites More sharing options...
trebor Posted February 15, 2015 Share Posted February 15, 2015 Try some Cimberio ptfe thread sealer. Works at -50 to + 150 c and 10 bars water pressure. Once stuck in with this it won't move you have to heat with a blow torch to soften it ? I used to use it on HP lpg lines. Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted February 15, 2015 Share Posted February 15, 2015 Have a look on e bay.you can buy brass 90 degree nipples for a couple of pounds or straight ones for pennies. Simple job to tap a thread into carb cover and you have a proper repair . Don't forget that the engine depends on the pulse to deliver the fuel so a bodge here can have a serious effect on reliability . Edited By Engine Doctor on 15/02/2015 10:47:19 Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted February 15, 2015 Author Share Posted February 15, 2015 I'll have a look on Ebay ED and yes I am looking not to do a bodge job! Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted February 17, 2015 Author Share Posted February 17, 2015 Right received a couple of Walbro WT fuel\pulse intake nozzles today in the post from mmrmodeltech.com who by the way gave great speedy service. Fortunately the OD of the brass pipe is exactly the same as the discarded one. The only thing different was the length of the brass shank on the replacement outlet is longer so I will have to make sure I don't tap in in too far. To help avoid this I laid the fuel diaphragm plate on the edge of a piece of 2" x 1" hardwood batten and heated the plate with my heat gun for about 20 seconds. I also dipped the brass shank of the nozzle into boiling water and then I tapped the nozzle in using a piece of hardwood dowel and a car body builder's rubber hammer. Hey presto it went in fine. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted February 17, 2015 Author Share Posted February 17, 2015 Last job now to screw the diaphragm plate back on to the carby body ensuring the internal gaskets are in the correct way ( always photo things when I take them apart….don't ask me why!). Hopefully all being well that's saved me £167 for a new carby from Ripmax for the sake of 7 quid for a couple on nozzles. Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted February 17, 2015 Share Posted February 17, 2015 Proper Job Quote Link to comment Share on other sites More sharing options...
john melia 1 Posted February 17, 2015 Share Posted February 17, 2015 £167 for a carb ????? Quote Link to comment Share on other sites More sharing options...
cymaz Posted February 18, 2015 Share Posted February 18, 2015 I bought a new Walbro carb from Phils hobbies in the US....I can tell you ,it wasn't £167..$70 more like! Edited By cymaz on 18/02/2015 06:48:42 Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted February 18, 2015 Author Share Posted February 18, 2015 That is Ripmax for you. Luckily I wouldn't need to resort to that. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted February 18, 2015 Author Share Posted February 18, 2015 For the record the same Walbro HDA 313 Carby from Phil's Hobbies is priced at $169.99 (Ripmax must have just changed the sign) which equates to around £112.00. Not sure what shipping costs/tax would be but I am not sure I would have been that much better off. Quote Link to comment Share on other sites More sharing options...
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