How much torque on carb boots?

[SIZZSAM]

I have a vacuum leak around my carb boots. I took them off to clean them up and put some liquid rubber to seal the cracks. I couldn't find any spec on the amount of torque for the carb boots in the manuals. I think the bolts are 6mm so I looked at the guide and only torqued them about 7 ft pounds. My gaskets weren't in too good of shape also. Now they are installed and leaking. I used starter fluid and it definitely raised the rpms when sprayed around the boots. I'm pulling the carbs back off and making some new gaskets but would like to know the torque. I would hate to break one off and then again I don't want them to leak again after reinstalling them. Any help would be greatly appreciated. These boots are on my 78 E. Thanks........................Sam

[randy]

7 ftlbs is about right, generally speaking, the 6mm bolts in the aluminum casings are torqued to 7 ftlbs, with good gaskets you shouldn't have any leaks. Check to make sure the bolts you're using aren't too long, run them in alone to check the depth, and use a lockwasher for good measure.

[SIZZSAM]

torque on carb boots

Thanks Randy I will try it again and make a better seal. It was probably my old gaskets. I labled the boots so I put them back on the same carb they came off of but the old gaskets were a little buggered up. I don't think they had been off before. Thanks for the help.
Sam

[Ivan]

I used Permatex 1A, which is hard setting formagasket on my carb boots, since gaskets weren't readily accessible, and it has worked superbly for over 5k miles.

[SIZZSAM]

torque on carb boots

Hi Ivan,
How did you torque the allen bolts? Is that permatex 1A for high temperature or does it matter. I have some of that so I may try it if I can't make some new gaskets. Thanks for the advice...............Sam

[bikerphil]

gaskets

You can go to an auto parts store and ask them for Ford 2.3L thermostat housing gaskets. They are pretty close to the right size. The holes line up, just have to trim a little off the outside. I've done this on my Standard and they work perfectly. Wait till you see the look on the guy's face at the parts counter when you ask him for 4.

[SIZZSAM]

carb boots

Thanks a lot BikerPhil, That's the kind of info I knew one of you had. It comes from trial and error and experience. I'll get the gaskets in the morning. Kind of on the same subject I was trying to install a new nozzle for the jet needle in my brother's Polaris mikuni carb. It wouldn't go back in. I needed something that would put equal pressure over the little "hood" of the nozzle. I reload my .270 ammo and I tried an empty .270 cartridge, slipped right over the hood and I was able to tap it gently back into the carb. Who would have thunk it. Thanks so much for the help............Sizz

[Ivan]

Hi Ivan,
How did you torque the allen bolts? Is that permatex 1A for high temperature or does it matter. I have some of that so I may try it if I can't make some new gaskets. Thanks for the advice...............Sam

1A is old school stuff, all brown and nasty. I think it came out in the 50's. Still works great for any place that fuel hits, and silicone won't hold up.

As far as torque, I typically don't measure those type things. I have a calibrated elbow that clicks at the right torque.

[SIZZSAM]

carb boots

I've broken off too many bolts and had to use easy outs too many times. It seems like if I can break something I usually do. I have three different torque wrenches now and I go by what the book says. I think with the new gaskets and permatex I shouldn't have any problem with 7 ft.lbs of torque. I'll let you know when I get everything back together and give it the starter fluid test. Thanks for the help...........Sam

[TADracer]

Not too tight.

7 lb/ft is not too much more than hand tight. If you dont have a lower scale torque wrench then just use an allen wrench and make it hand tight. That should do.

One other thing to check while you have the boots off. Try to pull the brass syncronizing nipple out of the boot. Sometimes these can come loose since they are just pressed in. I had one loose and found a vacuum leak there. If any of them come out then tap it back in gently and it should seal up again.

Minor cracks on the outside rubber of the boot usually is not the cause a vacuum leak since the inside of the boot is metal. But then ...... thats worth checking out too.

[SIZZSAM]

carb boots

Thanks Mike for the information. I have a 1/4 inch torque wrench that works in inch pounds so I can get it right. I bought the gaskets this morning and will work on it a little later. Thanks for the tip about the vacuum nipple. I didn't know they would work loose. I'll check that also. I should be good to go once I get them back on. I bought the bike in July and it had been sitting up for six years in a barn. It runs o.k. but I know it can run much better once I fix the vacuum leak. Thanks for the help..............Sam

[bikerphil]

intake gaskets

When using those automotive gaskets, it's a good idea to also use some gasket sealer on them.

[SIZZSAM]

carb boots

I just took the carbs off. There were no gaskets. The previous owner didn't put them back on. When I took them off it was the first time I had done it so I wasn't looking for gaskets. No wonder it leaked. I don't think it could have ran well for the previous owner. Too bad he never knew what it could do......Sam

[DiverRay]

Sam,
The factory carb boots had an "O" ring cast as part of the rubber. They did NOT use a gasket! The problem shows up 30 years later, when the "O" ring is hard or gone. The gaskets should do the trick!

[SIZZSAM]

carb boots

Thank you Ray. When I see some for sale on ebay they have gaskets with them sometimes. I bought the ford thermostat gaskets but haven't installed them yet, probably this weekend. The vacuum leak really screws up everything and can be so simple to fix. Thanks for the help............Sam