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Method for checking Monobloc float level, single carb

13K views 6 replies 4 participants last post by  Redmoggy  
#1 ·
I am in the process of "sorting" my 1965 TR6SR, fitted with an Amal 389/97 single carb. I have given the carb a good clean throughout and installed the Monobloc Major Stay-up Repair Kit:
http://amalcarb.co.uk/monobloc-series/389-series/repair-kits.html

I replaced all the jets according to this list (the #1 needle position was a bit of a surprise):
http://archives.jampot.dk/Technical/Carburation/Amal_Monobloc__numbers_type_and_use.pdf

As present, the bike seems to be running very rich, so before continuing to tweak the various carb settings, I thought it would be a good idea to check the fuel reservoir/float height first.

I see that there is a set of shims available in order to adjust the fuel reservoir level (but I have not bought one yet):
http://amalcarb.co.uk/washer-kit-for-setting-the-fuel-level-of-monobloc-carburettors.html

However, before getting into that, I wanted to be sure that I am going about it the right way. Here are a few pictures of my current approach.

First, just the carb, showing the "pip" on the float chamber end cover, which many seem to think is the correct height for the fuel in the chamber (any confirmations/repudiations appreciated). Note also that I have fitted the fibre/fiber washer supplied in the Repair Kit (itself a subject of some debate). Also visible is the new K&N filter:

http://www.triumphrat.net/attachment.php?attachmentid=93834&stc=1&d=1378650422

Here is my "method":

http://www.triumphrat.net/attachment.php?attachmentid=93842&stc=1&d=1378651558

http://www.triumphrat.net/attachment.php?attachmentid=93850&stc=1&d=1378651612


The only small-bore plastic pipe that I had to hand was not quite a push fit onto the pilot jet, so I used some wire to attempt to clamp/seal it. However, it did leak slightly, hence the glass jar. Also, I gently blew and sucked a little on the pipe to rock the fuel level to remove/expel air bubbles. When sucked a little, the raised fuel level would slowly sink back until it stabilised. That is when I took the close-up images of the fuel level. As you can see, the level is about 3-4mm, 1/8"-3/16", above the pip. However, the view from the other side shows a small air bubble, so maybe I have a false reading. I should probably go back and play with removing that bubble, but the weather tells me to stay inside today, and I really wanted to get feedback ASAP. :)

http://www.triumphrat.net/attachment.php?attachmentid=93858&stc=1&d=1378652124

http://www.triumphrat.net/attachment.php?attachmentid=93866&stc=1&d=1378652177

Mostly I'm looking for comments on this method and any alternatives. A Google search, and subsequent links provides a lot of comment about float levels, but no illustrations of how to check them, as far as I can see. So, all comments will be gratefully received. :)
 

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#3 ·
Thanks, Rod,
Following up on your comment I contacted Burlen, the Amal people. Their sales person confirmed what you said. Unfortunately, nowhere on the small leaflet enclosed with the kit do they mention that their kits include more parts than may be needed (there was also a second, thin rubber/neoprene flange O-ring which had puzzled me at the time). The Burlen man didn't seem bothered about the lack of info, though.
I suppose this is all obvious stuff to those in the know, but it caught me out. Incidentally, I went back and checked the detailed photos I took after collecting the bike, and there was no fibre washer fitted originally. Ho, hum…
So, yesterday, I removed the fibre washer and fired the old girl up and she was running a lot better. Cruised into town and back (only three or four miles) and all was well. Being an introvert sort, the attention that she attracted will be something I will have to adjust to, I suppose. Anyway, I was within yards of home, and she just died, with a big spit-back. Fuel seemed low, but not that low.
A little something for the weekend, then. :)
 
#4 ·
The unfortunate thing is that it is not obvious. Seems most of the time Brit bike suppliers assume we all have an innate ability to just know about all of the relevant change to the parts they send us. If it was'nt for these sites and people like Pete and John Healey, i think we would all struggle more! The O ring you mention sounds like the one for the flange of the carb?

I used to take my 66 TR6 to Worthing for the 'Sunny Sunday' show once a year. The attention takes some getting used to!

Rod
 
#7 ·
Dawsman, i really like that idea. Think i'll give it a go!

Rob, Sunny Sunday was the highlight of the year. A free to everyone Hot Rod/Custom show right on the sea front in the middle of summer. They had a small field between two hotels and packed it with all manner of cool stuff and a Rock n Roll band. I Googled it to see if any pics of my bike showed up, could only find this one of my old Kustom Moggy.



I'll stop thread crashing now and go away.

Rod