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72 Nordic Tillotson carb

2K views 57 replies 9 participants last post by  Plzsno 
#1 ·
So I'm trying to tune this HR 12A and just running it off a bottle. {not really running yet} My question is ... does this carb need the return line attached, and fuel in the tank to actually idle. It still seems to need a lot of choke to stay running. I just put a new check valve in .....no luck yet! Please help...
 
Discussion starter · #6 ·
I rebuilt it w/ Tillotson parts from EC carb. cleaned and replaced welch plugs. fulcrum looked level. I have not tried the pop off tester. I'm new to rebuilding vintage sleds. Maybe I should order a Pop off tester. Do you think Factory setting for the high and low jets are the best place to start. I think the sled had a different carb and someone may have stuck me w/ this HR12A....
 
Discussion starter · #8 ·
Thanks for the info. i'll be sure to check and see if the return is getting gas. I think it's dry. {i thought it was for air}
:unsure:
 
Discussion starter · #11 ·
After a deeper dive... this is a HR 12 A for sure. So the pulse holes all line up but this carb has a ... looks like brass plug in the pulse hole. Drill it out?:oops::unsure: that idea of mine, my really not loving .
 
Discussion starter · #12 ·
Thanks BB9076 I need to mention that I had a gas line in a bottle of fresh pre mix. Going though the rebuild one more time, just to make sure all is correct.
 
Discussion starter · #18 ·
Doo I need to find a different carb or might this model work . Other than I have no good way to hook up the choke cable.
 
Discussion starter · #19 ·
Just checking, if this is for a '72 Nordic 440e, the engine should be a Rotax Type 434E (should be a tag on the right side of the engine I think, around the fan housing).
And the snowmobile build date will be 1971 (as stamped in the tag on the tunnel).
Found it. TYPE 435
 
Discussion starter · #23 ·
Well... This was a barn find and 2 sleds on the old trailer under the vintage dusty skidoo covers, were last registered in 1986,. the other sled was a Skidoo 640 (his) engine seized from mice nest.
This Nordic 440e looked good.. and original, other than the carb looked like it was cleaner and had a manifold gasket that looked new. The guy that purchased the package ,said the 440 started. (actually it was obvious that he changed out the carb).
It had the owners manual, 2 new 40 year old plugs, extra drive belt, part of the carb intake cover and some fuses under the seat in a Skidoo bag.
I was looking for a sled that I started on in the 70s and was complete enough to go to a vintage ride someday. With some love... and luck ...and cussing .
I really appreciate the help that all of you have been with this journey!:)
 
Discussion starter · #25 ·
It has 2 needles. I'll open that pulse port tomorrow and set them at one turn each. FYI I am trying to get some pics to download.
 
Discussion starter · #27 ·
Success!. :)It was the pulse hole, actually ran pretty good on first few pulls. Ran long enough to get heated up and adjust for a smooth idle. Thanks !

I came back to it later, and now its running on one cylinder.... the PTO side sparks just fine NOT in the engine. Start it and it just blows fuel into the muffler.(and floor) on PTO side.
Compression is 140 on PTO side and 150 on the other. took off muffler for now. Whats the deal? Getting spark, gas and compression. Shouldn't this side run? Could the timing be that far off? I added new plugs points and condenser a few months ago. Ideas? :oops: :unsure:
 
Discussion starter · #30 ·
Well, No luck after 2 new NGK. Funny... its seems to spark just fine on the block. I even switched the hot plug over. FYI I'm doing this trial and error w/ the muffler off.
 
Discussion starter · #34 ·
Your points might be oiled up or you're condenser on that side is getting weak...
Dang... I hate to hear that... I just replaced them. Oiled up? Can that be cleaned up? Before I replace the condenser again, what else could I look for?? :unsure:
FYI I defiantly didn't smoke the condenser during install. (well I made every effort to NOT let it get hot.)
 
Discussion starter · #38 ·
Let me show my ignorance now. :unsure: :unsure: What does a blown seal have to do with my issue of... good test spark, spitting lots of fuel ,good compression, yet will not fire on PTO side when installed?
I really just don't know. And stumped, Thoughts? Should get a rebuild kit and start fresh? Thanks all!
 
Discussion starter · #39 ·
Let me show my ignorance now. :unsure: :unsure: What does a blown seal have to do with my issue of... good test spark, spitting lots of fuel ,good compression, yet will not fire on PTO side when installed?
I really just don't know. And stumped, Thoughts? Should get a rebuild kit and start fresh? Thanks all!
So are you thinking the blown seal could get in the points/area and get some oil where we don't want it.
 
Discussion starter · #42 ·
Great question. I pulled the spark plug wire and noticed many small copper strands in the cup. so I did cut off about 1/2 inch. Any ides on my next step?
currently reading older posts. I'm not the first w/ an issue like this. Could it be getting too much gas on one side? it suer does blow a lot of fuel all over. (Muffler still off drying out.)
 
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