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BJ8 Carb leak

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My carbs were fully rebuilt by apple hydraulics 5 yrs ago

But this time send em to Joe Cutro and get them done.
 
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Patrick67BJ8 said:
I always check the centering of the Jets when I rebuild my Carbs since I got them that far apart. I also like the SU tool kit to check proper Carb aoperation when throttled(both carb pistons must rise together).
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Yes, Pat, I agree the SU tool kit is good to have for adjusting the carbs during a tuneup or after a rebuild. My point was that a special tool kit is not required specifically for centering the jet.
 
Keoke said:
But this time send em to Joe Curto and get them done.
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Joe Curto rebuilt my HD8 carbs about 17 years ago and did a great job. However, when I tried to send him the HS2s from my MG Midget last week I found that he is not accepting any more workload right now. He does not have a "waiting list", so you have to keep trying until he is ready to accept the work. I found another (and only one) SU carb rebuilder in Greensboro, NC on the internet, but guess what: "I am not accepting any more work at the moment". That guy is moving back to England for several months. Looks like a good time for somebody else to get into the business.
 
Healey Nut said:
My carbs were fully rebuilt by apple hydraulics 5 yrs ago throttle shafts done etc the whole kit n kaboodle so I think I will just order two new diaphragms from XKs unlimited .

What is the lifespan of carb diaphragms ? 5yrs doesn't seem very long to me ?
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The diaphragms that were in my HD8 carbs when I bought the car in 1984 began to leak in 2010. I found the rubber cracked circumferentially around the metal spring cup in the middle. At that point, I had put 99,951 miles on the car. The diaphragms may have been original or not, I don't know. Modern rubber (along with other items) seems to be formulated for early failure, perhaps to generate more demand for parts, but I think the originals were much better quality than what is available now. Of course, changes in fuel formulations, such as ethanol, can also have a negative impact on longevity of the fuel system rubber parts. One would hope that problem has been solved by now.

I had the Armstrong lever shocks in my Midget rebuilt by Apple, and they began to leak within a year. Apple garnered themselves a negative reputation in the community. Don't know how they are now because I never went back to them for anything else.
 
Been to Joe's shop several times he's basically a one man operation so in order to get good work it takes time
 
BJ8Healeys said:
The diaphragms that were in my HD8 carbs when I bought the car in 1984 began to leak in 2010. I found the rubber cracked circumferentially around the metal spring cup in the middle. At that point, I had put 99,951 miles on the car. The diaphragms may have been original or not, I don't know. Modern rubber (along with other items) seems to be formulated for early failure, perhaps to generate more demand for parts, but I think the originals were much better quality than what is available now. Of course, changes in fuel formulations, such as ethanol, can also have a negative impact on longevity of the fuel system rubber parts. One would hope that problem has been solved by now.

I had the Armstrong lever shocks in my Midget rebuilt by Apple, and they began to leak within a year. Apple garnered themselves a negative reputation in the community. Don't know how they are now because I never went back to them for anything else.
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I've often wondered that excessive choke travel could help the cracking of the diaphragms sooner than without excessive travel.
 
Patrick67BJ8 said:
I've often wondered that excessive choke travel could help the cracking of the diaphragms sooner than without excessive travel.
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Yes, I've thought that myself. It seems logical that more travel would put more stress on the diaphragm, and the first place to crack would be near the metal cup because the stiffness changes abruptly there.
 
If you're still looking for pictures of HD-8s during a rebuild, I have way too many starting on this page, and continuing on for the next nineteen (19) pages; nine (9) pictures per page. For greater detail, a second click on any opened picture (640 x 480 dpi) with bring up a much higher resolution image (2048 x 1536 dpi).

https://spcarsplus.com/gallery3/index.php/reMKIII?page=4 Reassembly begins on page fourteen (14)

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Keoke said:
'm very dubious about some stuff from Moss . To much Won Ton Chang stuff .
I know it says genuine SU but .......
My carbs were fully rebuilt by apple hydraulics 5 yrs ago

Well HN:
if moss worried you them Orchard folks should have scared you to deaf.
However, they had new owners about 5 years ago.

But this time send em to Joe Cutro and get them done.
Click to expand...

I have had two sets of HD8s and two full sets of shocks done by "them orchard folk" no issues . Very happy with the service ....
 
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Tks Randy you must have way more time on your hands than I do to take all those pics etc .
Anyways ...I know I will have to have elastic wrists and double jointed fingers but what's to stop me taking the bottom end of the carb and replacing the diaphragm with the carb in place ?

Im up for a challenge .....everyone told me I would never get the overdrive back in the car without removing the gearbox but not only have I done it once but twice!!!
 
Healey Nut said:
Tks Randy you must have way more time on your hands than I do to take all those pics etc .
Anyways ...I know I will have to have elastic wrists and double jointed fingers but what's to stop me taking the bottom end of the carb and replacing the diaphragm with the carb in place ?

Im up for a challenge .....everyone told me I would never get the overdrive back in the car without removing the gearbox but not only have I done it once but twice!!!
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The last SUs I've dealt with are documented by the dates on those pictures, but while physically removing/replacing the carb bottoms may be possible, the act of centering the jet-well could take an additional week of frustrating labor. Better to just spend the 30 or 40 minutes up front and pull the carbs.

But hey, some people like a challenge__and doing things the hard way :cheers:
 
Healey Nut said:
I have had two sets of HD8s and two full sets of shocks done by "them orchard folk" no issues . Very happy with the service ... TEXT DELETED - VENDOR BASHING
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Ive had good luck with the supplier I believe your referencing. They monitor the forums to find out problems we're having with our parts. Most of the smaller suppliers resale their parts as well as other manufacturers parts.
 
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.I know I will have to have elastic wrists and double jointed fingers but what's to stop me taking the bottom end of the carb and replacing the diaphragm with the carb in place ?

Nothin Man!!
Just be sure after this expostulation N tell us how much fun you had.:highly_amused:
 
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Keoke said:
.I know I will have to have elastic wrists and double jointed fingers but what's to stop me taking the bottom end of the carb and replacing the diaphragm with the carb in place ?

Nothin Man!!
Just be sure after this expostulation N tell us how much fun you had.:highly_amused:
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I'd be afraid of pinching the edge of the diaphragm when trying to get it in place and tightened. Gravity plays a big part of doing it this way.
 
New diaphrams on the way & no they are not from the short wet green plant guys .

So so am I right is saying that the diaphragm is only "in use" when the choke is used . It allows the jet to be lowered to increase the mixture for cold starting . My point being I have no fuel leak when the choke is fully off .
I even tried with the engine off , ignition on fuel pump up to pressure I manually operated the throttle full open full closed numerous times ...no leak no drips no fuel pump pulses .
 
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Healey Nut said:
New diaphrams on the way & no they are not from the short wet green plant guys .

So so am I right is saying that the diaphragm is only "in use" when the choke is used . It allows the jet to be lowered to increase the mixture for cold starting . My point being I have no fuel leak when the choke is fully off .
I even tried with the engine off , ignition on fuel pump up to pressure I manually operated the throttle full open full closed numerous times ...no leak no drips no fuel pump pulses .
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The diaphragm replaces all those compression fittings on the HS SU carbs that keep the fuel from leaking out the bottom. It has fuel on top of it all the time. With the choke off the diaphragm isn't stretched, so if the hole/crack is small it may not open and leak.
 
So so am I right is saying that the diaphragm is only "in use" when the choke is used.

Well :
I guess you safe in sayin that HN.
It is kinda like a litte pump.
 
Keoke said:
So so am I right is saying that the diaphragm is only "in use" when the choke is used.

Well :
I guess you safe in sayin that HN.
It is kinda like a litte pump.
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I've had diaphragms cracked so bad that they really leaked bad without the choke pulled.
 
Patrick said:
" I've had diaphragms cracked so bad that they really leaked bad without the choke pulled ".

Yeah that is the normal failure mode.
 
Well I finally got time to pull the carbs , mr elastic fingers got em off in 25flat:encouragement::encouragement:
front carb diaphram is like swiss cheese . Rear is ok but its getting changed anyway . .
bet I dont get back on in 25 flat ??
 
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