1974 JD 400 Project

This is where you can post the story & photos of your John Deere Snowmobile project.
Cdnturboz
Posts: 162
Joined: Wed Nov 22, 2017 12:48 pm
Real Name: Steve

Re: 1974 JD 400 Project

Post by Cdnturboz »

I actually found it at HomeDepot up here in Canada, a quick search looks like it's available down in the states too:
Tape.JPG
https://www.homedepot.com/p/3M-Safety-W ... /100391699

I was having trouble finding a grip tape that was wide enough and then found it, just traced what pieces I had of the old grips onto these and then cut them out. Yellow strip is "fairly" close to the yellow stripe on bumpers (a hair different but looks close enough for me)

Edit: Jep - just noticed your from Grand Forks, I'm fairly certain I actually bought a couple of these from Home Depot in Grand Forks one of the times I came down to go shopping in Fargo.
Cdnturboz
Posts: 162
Joined: Wed Nov 22, 2017 12:48 pm
Real Name: Steve

Re: 1974 JD 400 Project

Post by Cdnturboz »

Think I got the carb all dialed in - idling about 2200rpm, high speed needle is about 1/2 to 3/4 out. No more major bog, plugs look brown which I think is a success.
Cdnturboz
Posts: 162
Joined: Wed Nov 22, 2017 12:48 pm
Real Name: Steve

Re: 1974 JD 400 Project

Post by Cdnturboz »

Getting the sled ready for the CPTC vintage show this weekend - found a NOS bumper only a few miles away from me for a great deal. Needs a quick polish from sitting in a shed all these years but should make the sled look better .
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400brian
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Real Name: James T. Kirk
Location: South Central Wisconsin

Re: 1974 JD 400 Project

Post by 400brian »

Awesome to see it all coming together!

'09 Vintage Challenge Survivor, and I wasn't late for supper!
'10, '11, '12, '13,'14,'15,'16,'17, '18, 19, 20, 21, 22 Vintage Challenge Survivor !
72 400 restored, Father bought new in '71
73 X8 restored
'74 340 green machine
'74 X8 9 time VC finisher
'78 Spitfire in progress
2 '75 340S 1 running, one on deck
'78 LF 440 future CC clone
'73 Skiroule RTX 440, 500 mi.
Cdnturboz
Posts: 162
Joined: Wed Nov 22, 2017 12:48 pm
Real Name: Steve

Re: 1974 JD 400 Project

Post by Cdnturboz »

Update - bit the bullet and picked up a new Mikuni carb . Installed it today runs great everywhere but idle. Settled on a 210 main and 25 pilot. Will idle great for a few seconds then slowly dies.
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400brian
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Joined: Wed Jul 20, 2005 12:00 am
Real Name: James T. Kirk
Location: South Central Wisconsin

Re: 1974 JD 400 Project

Post by 400brian »

I would suggest that the symptom you describe indicates that the engine is running out of fuel at idle. If you can't cure it by closing the airscrew a bit, then you may have to go to a larger pilot jet. That is assuming that you have adjusted the slide to give an acceptable idle rpm.

Remember that the air screw meters air not fuel. Closing it richens the idle mixture, opening leans it.

'09 Vintage Challenge Survivor, and I wasn't late for supper!
'10, '11, '12, '13,'14,'15,'16,'17, '18, 19, 20, 21, 22 Vintage Challenge Survivor !
72 400 restored, Father bought new in '71
73 X8 restored
'74 340 green machine
'74 X8 9 time VC finisher
'78 Spitfire in progress
2 '75 340S 1 running, one on deck
'78 LF 440 future CC clone
'73 Skiroule RTX 440, 500 mi.
Cdnturboz
Posts: 162
Joined: Wed Nov 22, 2017 12:48 pm
Real Name: Steve

Re: 1974 JD 400 Project

Post by Cdnturboz »

Thanks I’ll give it a try tonight and report back
Cdnturboz
Posts: 162
Joined: Wed Nov 22, 2017 12:48 pm
Real Name: Steve

Re: 1974 JD 400 Project

Post by Cdnturboz »

Had some time to mess with it quick tonight - screwed the pilot screw to lightly seated and it runs great and will idle forever(previously had the screw out 1.5 turns)

Do I need to get a larger jet? Ie a #30?
Cdnturboz
Posts: 162
Joined: Wed Nov 22, 2017 12:48 pm
Real Name: Steve

Re: 1974 JD 400 Project

Post by Cdnturboz »

Tried the larger pilot jet and got it to idle somewhat decent with .75 to 1 turn out.
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SS440-80
Posts: 275
Joined: Tue Jan 07, 2014 5:00 pm
Real Name: Robert
Location: SWEDEN

Re: 1974 JD 400 Project

Post by SS440-80 »

Good work :clap:
I think that you could go up to #32,5.
Sleds...
2xJOHN DEERE SPRINTFIRE 1983.
YAMAHA GP292b 1973
OCKELBO Trioman 1975
YAMAHA SRV 1982 (shrinked)
YAMAHA SRV 1990
YAMAHA SRV 1991
LYNX Rave 600ACE 2013
LYNX BOONDOCKER RE 3700 850 ETEC 2018
Cdnturboz
Posts: 162
Joined: Wed Nov 22, 2017 12:48 pm
Real Name: Steve

Re: 1974 JD 400 Project

Post by Cdnturboz »

Got it fully back together today, seems to run much better vs the Walbro or Bendix .

Been researching this for a while and never got a definitive answer. You ARE able to keep the factory glove box. Once cowling was back on i added a cheap 2 1/4” ID silicone 90 and tilted it slightly up so no gas/oil would run out if the carb ever spits some fuel back.

I had to mess with setting the choke and was able to actually remove the carb without removing the cowl which is a huge plus. (Just removed my silicone 90 first) I might look at adding a more ushaped silicone hose but will try this for now.
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400brian
Posts: 5894
Joined: Wed Jul 20, 2005 12:00 am
Real Name: James T. Kirk
Location: South Central Wisconsin

Re: 1974 JD 400 Project

Post by 400brian »

Good job!

'09 Vintage Challenge Survivor, and I wasn't late for supper!
'10, '11, '12, '13,'14,'15,'16,'17, '18, 19, 20, 21, 22 Vintage Challenge Survivor !
72 400 restored, Father bought new in '71
73 X8 restored
'74 340 green machine
'74 X8 9 time VC finisher
'78 Spitfire in progress
2 '75 340S 1 running, one on deck
'78 LF 440 future CC clone
'73 Skiroule RTX 440, 500 mi.
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