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#1 robert_p43 OFFLINE  

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Posted April 18, 2013 - 05:26 PM

HH100 with LME carb.  Depending on which manual I have looked at, I have seen both the high and low adjustments having initial turns from 1 1/2 to 2 1/2 out.  I finally have them adjusted so I can slow it down to idle.  I was having trouble keeping it running without being at about half throttle.  It now runs and sounds pretty smooth at most speeds but only if I keep it partially choked.  If totally unchoked, it needs to be reving at a pretty good rate to stay running smoothly.  What's the best fix from here, Is it the high, the low or both? 

Thank You


Edited by robert_p43, April 18, 2013 - 05:27 PM.

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#2 akretowicz OFFLINE  

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Posted April 18, 2013 - 05:46 PM

Sounds like you've got a plugged idle circuit somewhere.  Good cleaning should be the order of the day.


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#3 JRJ OFFLINE  

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Posted April 18, 2013 - 06:28 PM

I'll go along with akretowicz for the good cleaning.

 

 

Dick


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#4 superaben OFFLINE  

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Posted April 18, 2013 - 07:11 PM

Sounds like you've got a plugged idle circuit somewhere.  Good cleaning should be the order of the day.

 

I'd say yes to that, although I would try enriching the carburetor just a tad and seeing what happens.  I would play with the high speed screw first, too.  It doesn't hurt to try before going deep in the carburetor again.  The factory settings are usually close to 100%, but depending on the quality of the carburetor rebuild they will need to be wiggled a bit to get right for your engine.

 

akretowicz is right, otherwise. 

 

Ben W.


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#5 Deck_Drive OFFLINE  

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Posted April 18, 2013 - 07:21 PM

you should have the setting right, a plugged air cleaner could mess with your results as well. I have tinkered with these techys for a number of years now and every one seems to be a little different from the others. I would suggest adjusting the high speed till it runs smooth (At high speeds of course) then idle it down and mess with the idle screw.


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#6 robert_p43 OFFLINE  

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Posted April 18, 2013 - 09:06 PM

I had recently had the carb cleaned and rebuilt at a place where he rebuilds 500 or 600 carbs per year.  I went in to get a rebuild kit and I figured he might do a better job than me as I have rebuilt 0.  Of course, I did put the carb back on a few months ago, gassed it up and tried to start it.  Then it set till just recently. It is possible something got through.

The air filter is brand new as well as fuel filter.



#7 Deck_Drive OFFLINE  

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Posted April 18, 2013 - 09:10 PM

I had recently had the carb cleaned and rebuilt at a place where he rebuilds 500 or 600 carbs per year.  I went in to get a rebuild kit and I figured he might do a better job than me as I have rebuilt 0.  Of course, I did put the carb back on a few months ago, gassed it up and tried to start it.  Then it set till just recently. It is possible something got through.

The air filter is brand new as well as fuel filter.

Well, that was a good choice. I would think that you should check the float and filter. From there blast the passages on the carb out with some heavy cleaner and the air compressor. Make sure everything is tuned right and sound. What year is the engine? Does it have a fuel pump or anything?


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#8 robert_p43 OFFLINE  

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Posted April 18, 2013 - 09:32 PM

It's on a 1967 Sears Suburban 10.  It's gravity fed with no fuel pump. If readjusting doesn't work, I'll pull it and check the float adjustment and spray things out.



#9 Deck_Drive OFFLINE  

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Posted April 18, 2013 - 09:35 PM

Sounds like a plan my good man. Test 'er out and let me know lickity split and Ill see if I can help more. I've had numerous HH series engines and so far every one of them has knocked to some degree but all had power to spare and lots of torque. Onces you get her going you will have a tractor you wont want to get rid of.


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#10 MH81 ONLINE  

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Posted April 19, 2013 - 06:58 AM

Where are the settings now? I usually have best luck with 3/4 to 1 on low and 1 1/2 - 1 3/4 on high. But those are coarse tune settings
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#11 robert_p43 OFFLINE  

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Posted April 19, 2013 - 07:08 AM

I just read the following on another forum talking about someone elses carburator:

"The main jet is in the center where the middle bowl/mixture screw goes into. Up inside there is the main jet, it looks like a flat headed bolt with a hole in the middle and a groove for a flat head screw driver. Unless you are buying the new jet, do not remove it. A couple other guys referenced a bread tie wire or the likes, they were talking about using a small wire to go up inside there and clean it out. If it sat with gas in it for any length of time, it will probably be plugged with old gas build up which then causes rpm surge while running as it's starving for gas."

It makes me wonder if this may have been removed from my carb but not replaced.  I know that there is a fuel shot off, a sediment bowl, then the carb and everything before the carb was plugged solid.

Alan, I am not sure just where the settings are at this point, as it is finally running really well, except it seems like it needs a little more gas and a little less air.  It even starts pretty easy.  I have started it with 2 or 3 pulls at a cold start.  If I get time today or tomorrow, maybe I'll try to make a short video.  Anyway, if I try resetting the adjustments, I will check to see just where they are at this time and maybe start keeping a record to help myself.


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#12 MH81 ONLINE  

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Posted April 19, 2013 - 07:13 AM

The original tube was drilled in place, the replacements would have had a groove cut in the threads so gas can get around the tube, no matter where it is.
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#13 HDWildBill ONLINE  

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Posted April 19, 2013 - 08:52 AM

Have you checked for an air leak?  If the carb was professionally cleaned and you have a new air filter and you can't seem to get the setting right I think I would be checking for an air leak around the manifold.


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#14 TAHOE OFFLINE  

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Posted April 19, 2013 - 09:10 AM

Man, I get quoted everywhere  :rocker2:  :D

 

Did you have Mark at Carb rescue rebuild the carb? if he removed main jet, he knows to replace with upgrade. I would think if the main jet was removed an not replaced, then you wouldn't get smooth running WOT/ no choke which you said it runs good there, it would be surging. I'm thinking it's still needs fine tuning or like said before the idle circuit is plugged.


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#15 robert_p43 OFFLINE  

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Posted April 19, 2013 - 10:37 AM

No, I should have sent it in.  I was going to do the rebuild myself but when I went into a local shop to order a rebuild kit, they had one in stock.  The owner asked if I wanted him to do it and I figured it would be a good idea since I have no carb experience other than adjusting screws.  I remember he said the jet wasn't part of the kit but that was all he said about it.  If I had known about the jet issue, I would have asked him if he removed it.  By now, I am sure he wouldn't remember.  It's a pretty busy place.

I think I will check for leaks.  I think I can do that with spraying just like automotive vaccum hoses?






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