Carb Help

[rickf]

Let Vinny send you another carb. If his runs I would love to get your old carb and tear it down completly and check it out. Don't worry, I will send it back. I have never had a carb beat me yet.
Rick

[vtdeucedriver]

YOU GOT A DEAL RICK!......................Its weird. When i crack that nut, I will get fuel to the bowl. Tighten it and then try and start it and it will run for a sec and then quit. This will happen every time.

My question is...............is their a port that serves as a vent for the float bowl???

[rmclester]

all I can say guys is please post the solution when ever you find out what the problem is or was. This is one inquiring mind that wants to know
Rick

[rickf]

I just talked to Jeff on the phone and he said he would send it to me to check out. This has me really interested since I have never been beaten by a carb. I have found some that could not be repaired for one reason or another though. I will definitly let everyone know what I find.
Rick

[moose53]

i'm curious if the air cleaner isnt blocked off somehow creating a situation stopping the fuel feed.... have you tried running it w/o the air cleaner?

Jim

[vtdeucedriver]

Most of my testing has been without the aircleaner hooked up so no thats not it.

[muttguru]

A couple of years ago, I came across a carb that allegedly "wouldn't work". After many sleepless nights thinking about what the problem was, I discovered that the filter head (that big head bolt that holds a tubular wire gauze filter) was the wrong one. It was a similar problem to the one you are having. When the bolt was tightened, the drill hole in the carb body was being blocked by the filter head bolt. Can't remember now if it was an A2 filter head fitted to an A1 carb (or the reverse) but when I changed it, the carb worked. The carb's owner eventually admitted that he had dismantled two carbs (at the same time !!!) and had re-assembled one carb with the best parts from the two.
I may still have that carb on the shelf so if it stops raining/snowing any time soon, I'll check.

[rickf]

Ken, That is along the lines of what I was thinking. I know a lot of the parts are different between the old and new carbs.
Rick

[vtdeucedriver]

A couple of years ago, I came across a carb that allegedly "wouldn't work". After many sleepless nights thinking about what the problem was, I discovered that the filter head (that big head bolt that holds a tubular wire gauze filter) was the wrong one. It was a similar problem to the one you are having. When the bolt was tightened, the drill hole in the carb body was being blocked by the filter head bolt. Can't remember now if it was an A2 filter head fitted to an A1 carb (or the reverse) but when I changed it, the carb worked. The carb's owner eventually admitted that he had dismantled two carbs (at the same time !!!) and had re-assembled one carb with the best parts from the two.
I may still have that carb on the shelf so if it stops raining/snowing any time soon, I'll check.

Well the one in the pic is not the one that I have!!!!!!!!! mine is a pretty big nut..........I think 11/16 or 3/4. It has a screen with a bottom support washer with a stand off tube and screw that goes into the bottom of the plug. I will race home in the am and take a pic of it and the assy.

You know now I think of it. I believe that there were 2 gaskets under there but I have installed only one that it calls for. maybe it was there for a reason???

[Miltrans]

Hi.
Just thought I'd send the float ajust pictures. So you get that part right also now that you have it all appart.
We have just had the same discussion on the Danish Forum (no! not a place where we sit and eat sweet pastries)
Danish army sold on auction all their Mutt parts some years back. Now these carbs are getting used on restored vehicles and it turns out that they are not correctly ajusted from the factory.
Chris

[muttguru]

Hello Chris,

how are you doing? Hope you are having better weather in Dk than we've got here in Uk.

Please don't mind if I add an extra comment to your post.

In your second page from the TM, it shows the float drop as 3/8". Unfortunately, the TM is very misleading here. Although the TM says .....a minimum of 3/8", most people (including mechanics in the mil) read that and think that 3/8" is the actual setting..... it isn't !! It can be much greater than 3/8"....and it should be greater, too.
If the drop is set so that it won't go further than 3/8", then the carb is starved of fuel and this is why most owners end up running with the choke part-way out. The key word here is "minimum". I've found that when the float drop is unrestricted....the carb runs exactly as it should.

Jeff, when you've sorted out the filter head problem, adjust the float drop to greater than 3/8" and see what happens.

[Miltrans]

Hi Ken.
Nice to see you are still active! Hope to see you at Beltring this year. We will be bringing an assortment of the new body panels for show and sale.
Have just sold 3 of my project Mutts to guys that are going to restore them, so hopefully they will be on the road soon.

Thanks for the extra comment on the "drop" measurement.
I have found that many float arms have been altered (bent with a pair of BIG pliers) in such a way that the measurements dont apply. Usually because the odd shape of the float means that the amount of fluid in the chamber is not correct even thout the "closed" measurement is correct. This also results in the "drop" measurement has to be altered before I found the real reason.
I too thought that is was a bit small opperational movement that the float had acording to the manual, so I usually gave it a bit more "drop"..like to know that the valve opened.
On the same subject, one of our group - Thomas - has found out that some carbs are warped in the mating surfaces and thus are not propperly sealed in the middle where the jet is. By checking with a strait edge, it is possible to see if it needs attention. A fine file can solve the problem.
I have asked him to write an article about it in our club magazine. When it comes, I will translate it here and send it to you so you can put it on your site also.
Chris.
PS did you get the photo of that strange back rest on one of the front seats of the M.825 I have?

[vtdeucedriver]

OK all..................well it runs!!!! It still hesitates like it always did but it DOES run! Now for the reason. Now that I have calmed down, the float was WAY out of adjustment! Now when I 1st took it apart, I checked it and it was fine. So it sat on my tool box at work until the work was done at the end of the shift. I assembled the carb and brought it home. The rest of the times I had it apart I never checked it again until this mornings post!!! I had realised that it could be the only reason. So point being, one of my fellow workers is a DIRTBAG!

So anyways, with very dead batterys, she started right up!!! After a good laugh and a moment of rage I calmed down until my next issue surfaced its ugly head!!!!

On to another post!

[rickf]

Like I said before, It always turns out to be something simple that we beat ourselves up for afterwards for not finding it sooner. We have all done it, Time to move on. The hesitation is either the accelerator pump or more likely in your case it is not up to tempurature. If it is not up around 170 - 180 it will bog.
Rick

[Floyd]

Well done Jeff, glad it got all sorted out.

Floyd