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M

mightymidget

Jedi Knight
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Well I got my $500.00 Midget running tonight, at first gas was pooring down carb. took top off cleaned put back together and that stopped. But when I got the motor running it was all over the place, won't idle, dead spot off idle, etc..

Anyway suggestions, it is a weber, been sitting for years, carburators really are beyond my understanding. Hap who is close is way behind etc... anyone near South Carolina that I can send carb to that will treat me right, should I uy a new Carb (weber) or should I Buy some used/rebuilt SUs.

I have two old sets but they are off 1098 engines
 
Use the SU's from the 1098's- you will be surprised at what they will do!
BillM
 
:iagree:
 
My DGV finally gave up the ghost and I had to buy a new one. My booster venturi was loose and I tried, but couldn't get it straight. Try the other carbs you have.

I'm confused by the thread title, did you mean "need a hand"?
 
No the title is right, I needed a "name" of someone to send my carb to to have rebuilt, if I cann't figure it out myself
 
Hap is a nice name, he does carbs, SUs for sure.
 
My $.02-- If you're going to spend the dough, get the SUs. The weber (DGV) is pretty average at best on these cars. The SUs, though more intimidating to some people, are far superior. However, if you've ever tackled the job of rebuilding a set yourself, your understanding of how these carbs work goes way up. Also, you then know the theory behind the function and tuning and you can far more easily tune these carbs for a better result. It's all about getting them matched up which isn't nearly as hard as everyone seems to think.

By the way, you'll esentially never get rid of that off idle hesitation with the DGV.

JACK
 
lesingepsycho said:
By the way, you'll esentially never get rid of that off idle hesitation with the DGV.

JACK
Click to expand...

I finally got rid of mine by buying a new carb.
 
If the HS2s you have are not worn out at the throttle shaft, they are not impossible to rebuild yourself. There are plenty of resources on the web and I think there are even youtube videos showing the process (John Twist?). The kits are not cheap (~$125 from moss), but it can be done. There are some really good step by step procedures for getting them tuned once they are on the car (something you would have to do even if you sent them out).

https://www.nicoclub.com/archives/2-write-ups-on-tuning-su-carbs.html

Do one at a time. If you have more than one set, take one of the junkier ones apart first. I think any of the sprite midget workshop manuals have a procedure for rebuilding carbs.

Brian
 
lesingepsycho said:
...you can far more easily tune these carbs for a better result. It's all about getting them matched up which isn't nearly as hard as everyone seems to think.
Click to expand...
Jack is right. Tuning is a matter of adjust, check, adjust, check, repeat 20 times.

Brian
 
This is one of the reasons I want to find a set of HS4's for my Nissan 1500.
The downdraft carb on it is crap, apparently they are nice when new but mine is very far from new.

Now I have a cylinder head and intake for a set of SU's I am itching to get it put together. First things first of course, going to work on brakes at tomorrow's NODoody gathering.
 
Weber, dead spot right off idle. You can drill an extra hole in the area that handles the mid range air. I used to have link to a site where a guy had pictures but that was before my computer needed a rebuild. Most of the time if its got the jets that came with the kit and nobody has changed them then it has to do with someone putting too open an air filter or to open an exhaust on it. These things get temperamental because the DGV (or Holley5200) was designed for a bigger engine and on a 1275 the air flow is really low at idle and right off. It ends up getting lean right before the shot of gas hits it from the force pump. Shut the air down a little and see how it does. You can get rid of that dead spot. Problem is that fiddling with jets and jet kits gets expensive and that is not the problem usually. I don't know anything about SUs, Hap is the man on that. With the dgv its a lot like a motorcycle carbs (which I have worked on a lot). To troubleshoot the problem is not about rpm its about throttle position and what part of the carb is being used at that point.
 
Rebuild the SUs. I had ZERO experience and simply followed the directions in one of my manuals. The only thing I couldn't do was install the oversized throttle shafts.

That said, I needed a lot of help getting them tuned, but the point is that you CAN do the rebuild yourself. It was actually very easy. Just be careful to do it in a clean area. Yes, the parts need to remain clean, but if you drop one of the tiny washer/cup things, they will, like magic, disappear into thin air. Ask me how I know.
 
I am going the cheap route, buy some carb cleaner,and try just cleaning the Weber....takeing plenty of photos during removing parts
 
I had my SU's rebuilt professionally. figured I didn't need to know everything. That being said, they are very easy and simple carbs. Here is an article on reaming the throttle shaft. It should be an easy DIY. And, if you dis-assemble and re-assemble an SU carb enough times, eventually you will have two carbs.

https://www.chicagolandmgclub.com/techtips/general/545.html
 
I'm with EVERYONE who is advising you to rebuild your SUs. I went through heck trying to figure out why my Weber would not rev above 2500 RPM. I finally took the coaching and dumped it. I spent a pretty penny to have my SUs rebuilt and do not regret a single dime that I spent. Take the wise counsel from these guys and get rid of the Weber.....

You can get around $150 from some other unsuspecting buyer that will offset the cost of fixing your SUs. That's with the manifold.
 
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