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Mickey Richaud

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Hey MGFever -

Welcome to the forum. You'll find lots of assistance here. My vote would be sticky or poorly adjusted floats. But I'm sure there are other tips forthcoming.

Mickey
 
Thanks Mickey! I was thinking that was a likely culprit. I had a teaspoon of mud in each of the bowls when I inspected them this spring. I messed up and did not flush the tank before I put it on the road last year. I think I'll pull them off again and re-check the floats.
 
Welcome to the forum!

There might be more dirt in there causing the float needles to stick open, but then again the needles or seats might be bad too (that seems to be common with the HIFs).

Since you pretty much have to pull the carbs off to get to the floats you might also pull the pistons out and check to make sure the needles aren't badly scored up (or bent), and that the jets are clean and not ovaled out. The biased needles in the HIFs sometimes cause the jets to wear away on one side causing problems. While you're at it also check that the needle's shoulder is flush with the bottom of the piston and not shoved up inside it. They'll still work like that, but you need to really back the mixture adjustment out to compensate for it.

There's always the chance that the enricheners are stuck on "rich". They're a rotary-valve arrangement of some sort, so I'd imagine it's possible for them to cause problems.

Lastly, there has been talk about how the emissions hook-ups can cause either excessively rich or lean running. The two "vent" lines coming out the upper/sides of the carbs connect to each other then to the carbon cannister via a T-fitting. There is a slight vacuum on these lines and, as I said, some people claim if they are disconnected, vented, or plugged they can cause problems. To be honest I've tried to plug mine, vent it, etc, and have found absolutely no difference in running. There are the other two lines that end up going to the crankcase though, you might check that those aren't plugged.

Good luck -- Scott
 
Hi MGFever,

Welcome to the Forum. You’ll find lots of great folks here with a wealth of information to share and pass along. Good humor and a common bond is the name of the game with this group.

Be sure to take a “Glamour Shot” of one or all of your cars when you feel it’s presentable enough and add them to the MG Reader’s Rides Gallery.

patriot.gif
 
Hi everyone! I'm an old MG nut that is still learning and hoping to explore another knowledge base. I originally had a '68 and a '74 MGB in the early '70s. Had to let them go when kids invaded our lives. Now that I have a little more time, I have jumped in with both feet again. I rebuilt a '74 Midget first including paint in my garage. I then bought a '72 MGB rustbucket and a '72 GT basket case. I just got the GT on the road last summer. The B is still waiting for a load of work. All three of these cars should have been crusher material but I just couldn't let them go that route. I do all the work myself except for the machine work on the engine and I do stumble a bit now and then. Currently I'm having problems getting the GT running decently. I'm sure it's a problem with the HIFs. I'm running extremly rich even though I have the settings at the 2 turn starting point. They are even cold after running a short time. I did have a lot of dirt in the bowls this spring but cleaned them up and even pulled amd cleaned the needles. Any thoughts?
 
Thanks everyone! I put up a couple of pictures on the site. No I'm not a purist! That is Viper red two part epoxy with a clear coat on both the Midget and the GT! I wanted to be seen!
I did replace the needles and seats but I didn't check out the rest of the details that Scott mentioned. I'll pull them again and do a proper job this time!
rolleyes.gif
 
I agree with Scott. I just have one thing to add. When you get the floats out, you might shake them and see if there is any gas in them. If one is leaking It will cause the float to sink or ride low and cause the one carb to run rich. That might make you think that both are running rich due to the black smoke caused by one of them.
If you suspect dirt from the tank in the float valves, you might try one of those glass filters where you can see the dirt in the filter. They are available in most auto parts stores.
 
I had a similar problem on a "72 Midget that had been in storage for 15 years. The vent hoses to the carbon canister had been disconnected, and mud wasps, or some such had plugged the hose. At idle, looking in the carb throats, there was enough fuel spraying out of the jets to run at about six grand! I replaced the hoses, and it's been fine ever since.
Welcome aboard.
Bugeye58

[ 06-14-2003: Message edited by: Bugeye58 ]</p>
 
Thanks Bugs! I didn't think to check those hoses. I did order some new throttle shafts and gaskets after the inspection. Both shafts were a little scored. The bushes still looked good and not out of round so I'm holding my breath on that one. I did see an article once by someone out of Chicago that described how to re-bush these yourself. Never found a source for the reamer or the correct bushes though. I think I may have had the wrong washers on the Jet Guide too so I ordered new washers for those.
 
Thanks Mrbassman. That is one I had seen in the past but I thought about it awhile and its in one of the issues of MGB Driver. I'll have to look it up. They had a source for the reamer that was even less and claimed they had rebuilt carbs with very good results. I'll follow up if I find the sources.
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OK, just another thought,the reamer is designed to open up the bushings for over sized throttle shafts.
Moss has a reamer tool for that and is .010" oversize but the cost of it is $125. Look in the tool section of their catalog page 60 in the one I am looking at right now. (Issue 1 2002)
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you can probaly buy a reamer from mcmaster Carr. or a simalar supply house for much less...as long as you know the size you are lookin for
 
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