MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGB Technical - HIF Carb Rebuild Kit ?

I need to rebuild my HIF's on my 1972 BGT. I have owned this car for just over a year now. It runs pretty well as I have done some adjusting of the carbs, and replaced the points, rotor, spark plugs and adjusted the valve lash. I have removed the float covers and removed a lot of debris from the float chambers, this was done with the carbs still on the manifold. The rear carb still is running rich, and I believe is overflowing. I do not have the overflow outlet piped to the charcoal cannister. I just have a hose to carry it away to beneath the car.

My question is: The rebuild kit that moss sells (142.95) contains a "Jet". While the one that Vicky Brit sells does not (99.90). How important would it be to replace the jets? I am thinking my main problem is the needle valve and seat.

Looking for any recommendations regarding which rebuild kit I should order. Any other helpfull rebuild info would also be appreciated.
John Fraioli
1972 MGB-GT
1979 mgb roadster
John F

Have a look at www.burlen.co.uk
Just buy the parts you need
Ed Campbell

What an insane price either way! From Sussex classic car parts, the rebuild kit is only 31.34. I know you're talking in dollars but even still, thats only $61.88. Ive never been tempted to buy anything from Moss. Theyre far too expensive. Ive been less than impressed with burlens service as well. I ordered a rebuild kit for my fuel pump, and 3 days later they came back to me by email and told me it was unavailable and on back order, with no indication of when it would become available. After I sent them an email asking them to give me more information, they didn't reply. Their website is crap as well and nigh on impossible to find anything on. If I could have ordered it from Sussex, I would have done and there'd have been no fannying about either. I emailed sussex asking them if they could start stocking the kits to rebuild the pumps. Just my little rant for the day. Oh and the kit from sussex is top notch. I used it on my own carbs and it comes with the jets, needle valves and all that jazz.
Ross Kelly

I thought the price was high also considering the kit for a ZS Carb is $29.95 at vicky brit.

Just to make sure we are on the same page though, the kit that Moss sells will do both carbs. The kit that Victoria British sells does one carb at a price of $49.95 so to do both carbs would be $99.90

John

John F

John,

I get most of my parts from Bob at Brit-Tek, LTD. in New Hampshire or from Gordon at the B Hive in South Carolina. You might compare prices at those places.

Charley
C R Huff

The price from Sussex is for both carbs as well, and its the original SU rebuild kit that burlen would be supplying you.
Ross Kelly

Make sure to do the throttle shaft bushings and seals...Made a remarkable improvement on my su's...and solder the damnable poppet valves....
pete

A tip for soldering the poppet valves on that note... I found I needed to get the valve hotter than the fires of hell before the solder would adhere and then it was a mess of solder everywhere. Instead I twisted off the spring top and removed the spring. Then I was able to solder the lower ring to the poppet valve shaft and it meant that the whole thing was a lot smaller too. You'll see what I mean more clearly when you have the throttle plate removed anyway.
Ross Kelly

And also...get rid of those dumb lock nuts and replace with screws...so you can adjust easily...
pete

I recently overhauled my HIF carbs using a Burlen service kit complete with the jet assemblies. I had a problem with the spindle seals being totally shot and the new kit has fixed a leaky carb. Unfortunately I now find one of the new needle valves occasionally sticks and requires the old screwdriver handle tap to free it up. It's another thing on my 'To do list'!

If you would like a copy John F I can email you a copy of the detailed service sheet that comes with the Burlen kit, it also includes helpful instructions on tuning the carbs.
<--- email

pete Pgh wrote:

"And also...get rid of those dumb lock nuts and replace with screws...so you can adjust easily... "

I think you mean replace the lock nuts with springs(?) I'd hate to think of someone wrecking their carbs by forcing a couple of self-tappers into them!
Mike

Right!...springs, not screws...Also, J. Twist recommended 90w oil in the dashpots for older, worn carbs...and it works nicely....
pete

I use 3 in 1 oil in my dashpots. I dont know whether you have that in the USA. Its a light machine oil. I find that works nicely for me.
Ross Kelly

Ross,

Yes, we have 3-in-1 oil in the States. But, I think that is a whole lot thinner than what most people use. ATF is about the thinnest I have heard of in common use.

I think most books recommend the same thing that you run in the crankcase, and like pete says, John Twist recommends 90 wt gear oil. I haven't tried that yet. I think I have either 20w50 or straight 30 in mine at the moment.

Given all the trouble you have had with carbs, tuning, and mileage, maybe you should experiment with heavier oils in the dash pots. And then, of course, report back to us with the results.

Sorry if this posts twice. The computer blanked out for a moment and I don't think it posted the first time.

Charley
C R Huff

Like C. R. Huff, I like Brit-Tek for most parts but for quality carb parts, Joe Curto is hard to beat. I recently bought kits for HIF 4's from Joe. His complete kits include everything you need, except possibly new floats. New Floats are extra. Price for complete kits, including new throttle shafts and new solid throttle plates is about $150; and that includes shipping.

Mack

M Sneed

Thanks Friends for all the comments.

Mike, Yes please e-mail me the detailed service sheet that may be very helpful.

Pete, Yes, I have been using the 90 weight oil, I saw John Twist using it while doing his rolling tech session while I was out at MG2007 in Sonoma Calif. last summer. I should say I have been using it on my ,79B that has a leaky o-ring in my single ZS carb. I am still using the 20w-50 castrol in the Dual SU's. on my '72 BGT daily driver.

Keep the comments coming, I'm sure the info will be helpful when I start the rebuild soon.

John
John F

Well I was recommended to use 3 in 1 oil but I'll try a bit of motor oil in there instead to see if there's a difference. Next time Im filling the dashpots Ill do it.
Ross Kelly

John F, you have email.

I've always used standard engine oil in my SU dashpots without any problems, this was always the manufacturer recommendation. 3-in-1 oil is way too dear for a tight-wad like me and as the oil is only there to provide damping assistance and not lubrication it doesn't need to be of the best quality.

Any one looking to strip down their carbs (or any reasonably complex sub-component for that matter)would be well advised to use a digital camera to record the strip-down procedure so you can refer back to how thing were before you enthusiastically dismantle things into a collection of umpteen funny-shaped little bits. I'm sure I'm not the only one who's put the carb linkage back on upside-down when reassembling :-)

Mike
Mike

I did that as well actually! lol. It is very easy to do. Yeah photos are invaluable, and with a good quality camera in good light so you can enlarge them if needs be.
Ross Kelly

This thread was discussed between 22/06/2008 and 25/06/2008

MG MGB Technical index

This thread is from the archive. The Live MG MGB Technical BBS is active now.