Snowmobile hard starts - part 2

[Pulleye16]

Yes, I’m still trying to fix this old sled. I need help identifying the purpose of these two hoses labeled on the pic…which run into the air box.

I put red indicator on the two hoses.  The air box is where the coors can goes.

Reason I’d like to know, is I read that the port for those two hoses which connect to the carb is s great port for adding a primer line.

So basically, if I rerouted those hose from the air box to my primer bulb (which I need to install) would that cause any issues???

Thanks much

[glenn57]

  i'm far from a snowmobile fixit guy, but why wouldnt there be a primer there already? i have a 95b skidoo it has a primer but no choke.

would those hoses not be for air into the equation for the mix to properly run the sled??????

[LPS]

I have a primer on my 98 Ski Doo too.  Just replaced it with a new one.  A new one was under $30.   Someone will tune in that knows what those hoses are for.

[Pulleye16]

It’s a 1998 Indy 500. Has a choke but no primer.  After much digging around, it was recommended to try an add a primer. Just need to figure out where to plum it into the carb and these hoses seem like a great port…but I’m guess they serve a purpose. Lol.

[Boar]

Is this a tripple or twin

[Pulleye16]

Is this a tripple or twin

Twin

[LPS]

Leech is a sled head.  Hoping he tunes in.  I wonder if they aren't just a fumes recycling thing that go back through the carbs to burn it all type of thing.  ?????  We know it gets air from the front not from those tubes.  That may be the place to hook up your primer.  Like I said I got the exact thing that was stock on my sled for I think $27.  It say Made In USA right on the knob.  I love that.  SO it is probably a common primer that is used in many sleds.  Put a Y in it and should work.  DO NOT TRUST MY INFO!!!   I pump the primer and it takes a couple of pumps and you can feel that it is actually pumping gas and not just air.  When it does that I give it a couple more pumps and it starts right up.  I then just give it one pump now and then whilst it warms up.  First time I ever had a sled with a primer and works pretty good.   

[Boar]

Oh thats right, the 600 is a triple

[roony]

Had that same sled. Seems like we had to have the carbs cleaned every year.

[glenn57]

Had that same sled. Seems like we had to have the carbs cleaned every year.

my skidoo sat for 4-5 years in my moms shed 5 miles away. really didnt do much with it, decided it was going to the cabin as thats where i'll use it most. has a guy go through it, basiclly the carbs, runs like a champ now. but i put in the non-oxy gas and every time i'm at the cabin i start it and let it run for 20-30 minutes!!!!!!!

they say thats the best for it. not sure why now that its 200 miles away i got more time to take care of it then when it was 5 miles away????

[Pulleye16]

Thanks much for the info so far, you guys are great.

The carbs “should” be cleaned as I went through the entire sled this fall; cleaned carbs, replaced fuel lines (even into the tank), filters, adjusted carbs, throttle, and choke. Replaced a few bearings and the drive axel.

Really wish she would have started right up after all that but nope. I’m “hoping” the primer kit I bought will crutch this sled along for another 5+ ice fishing season.  Just getting to old to pull the damn cord for 20minutes straight. Lol

[roony]

Have you tested the plugs to see if you have spark?

[Leech~~]

Thanks much for the info so far, you guys are great.

The carbs “should” be cleaned as I went through the entire sled this fall; cleaned carbs, replaced fuel lines (even into the tank), filters, adjusted carbs, throttle, and choke. Replaced a few bearings and the drive axel.

Really wish she would have started right up after all that but nope. I’m “hoping” the primer kit I bought will crutch this sled along for another 5+ ice fishing season.  Just getting to old to pull the damn cord for 20minutes straight. Lol

Skidoos are the only brand I know of that used a primer instead of a choke.  If the system was not designed to work with a primer I personally wouldn't try to reengineer it in my garage.  I'm not one to question peoples word or their work. But, looking at the picture above of all the crud on those two carbs, they sure don't look like they were pulled off and fully tore down and cleaned.  The choke causes a vacuum in the carb drawing fuel up into the carb giving it extra gas just as a prime does. If your not pulling up the gas with the choke your needle and floats are dirty, or you have very low compression.  Did you do a compression check yet?  Also, yes the two lines you have marked are vent hose going to the air box. 
So many little thing to check, here's another!  Are your plug dry or wet when it's not starting? 

[Jerkbiat]

Good explaino Leech! 

[Gunner55]

  No sled head here, but when I have starting issues, checking the plug(s) is 1 of the 1st things I do. 

[Leech~~]

No sled head here, but when I have starting issues, checking the plug(s) is 1 of the 1st things I do. 

Yep #1.
Spark, compression, fuel, spark, compression, fuel. The 3 things you need to run a gas engine, that's easy. The hard part comes try to figure out why you don't have one of them? 

[Gunner55]

Yup, checking for spark is usually a close 2nd.

[Leech~~]

Yup, checking for spark is usually a close 2nd.

OK so I forgot Keys! 4 things! 

[Pulleye16]

Thanks much for the info so far, you guys are great.

The carbs “should” be cleaned as I went through the entire sled this fall; cleaned carbs, replaced fuel lines (even into the tank), filters, adjusted carbs, throttle, and choke. Replaced a few bearings and the drive axel.

Really wish she would have started right up after all that but nope. I’m “hoping” the primer kit I bought will crutch this sled along for another 5+ ice fishing season.  Just getting to old to pull the damn cord for 20minutes straight. Lol

Skidoos are the only brand I know of that used a primer instead of a choke.  If the system was not designed to work with a primer I personally wouldn't try to reengineer it in my garage.  I'm not one to question peoples word or their work. But, looking at the picture above of all the crud on those two carbs, they sure don't look like they were pulled off and fully tore down and cleaned.  The choke causes a vacuum in the carb drawing fuel up into the carb giving it extra gas just as a prime does. If your not pulling up the gas with the choke your needle and floats are dirty, or you have very low compression.  Did you do a compression check yet?  Also, yes the two lines you have marked are vent hose going to the air box. 
So many little thing to check, here's another!  Are your plug dry or wet when it's not starting? 

Thanks much Leech and others! You can ALWAYS question my work-and give it to me straight, I won't get butt hurt over it.

But, regarding the crud on the carbs, this is definitely a before pic. LOL.  I snapped dozens of photos while working on this sled, so I knew how to put the puzzle back together. The sleds at the cabin now so these were the few pics left on my phone I had showing the vent lines.

Compression was damn near perfect in both cylinders ~ 120psi
New spark plugs and gapped (I'll double check spark condition)

Choke adjustment "seemed" good when I went through everything...

I feel I have a leak somewhere. I don't (???) think it's a problem with the carb as it was hard to start before I cleaned it up, and still hard afterwards. All fuel lines have been replaced so I feel they are not leaking (old line had a small hole).

My thinking (and it's probably wrong) was even if I have some failure with fuel pressure, the primer will help. It stays running, just can't get the darn thing to start up. It's used only for ice fishing.

Just to confirm Leech, the vent lines identified in the pic's above SHOULD NOT be tampered with...e.g. used as a primer line?

Thanks

[Jerkbiat]

My guess is you may need to rebuild the fuel pump. The diaphrams can get hard over time.

[Leech~~]

Thanks much for the info so far, you guys are great.

The carbs “should” be cleaned as I went through the entire sled this fall; cleaned carbs, replaced fuel lines (even into the tank), filters, adjusted carbs, throttle, and choke. Replaced a few bearings and the drive axel.

Really wish she would have started right up after all that but nope. I’m “hoping” the primer kit I bought will crutch this sled along for another 5+ ice fishing season.  Just getting to old to pull the damn cord for 20minutes straight. Lol

Skidoos are the only brand I know of that used a primer instead of a choke.  If the system was not designed to work with a primer I personally wouldn't try to reengineer it in my garage.  I'm not one to question peoples word or their work. But, looking at the picture above of all the crud on those two carbs, they sure don't look like they were pulled off and fully tore down and cleaned.  The choke causes a vacuum in the carb drawing fuel up into the carb giving it extra gas just as a prime does. If your not pulling up the gas with the choke your needle and floats are dirty, or you have very low compression.  Did you do a compression check yet?  Also, yes the two lines you have marked are vent hose going to the air box. 
So many little thing to check, here's another!  Are your plug dry or wet when it's not starting? 

Thanks much Leech and others! You can ALWAYS question my work-and give it to me straight, I won't get butt hurt over it.

But, regarding the crud on the carbs, this is definitely a before pic. LOL.  I snapped dozens of photos while working on this sled, so I knew how to put the puzzle back together. The sleds at the cabin now so these were the few pics left on my phone I had showing the vent lines.

Compression was damn near perfect in both cylinders ~ 120psi
New spark plugs and gapped (I'll double check spark condition)

Choke adjustment "seemed" good when I went through everything...

I feel I have a leak somewhere. I don't (???) think it's a problem with the carb as it was hard to start before I cleaned it up, and still hard afterwards. All fuel lines have been replaced so I feel they are not leaking (old line had a small hole).

My thinking (and it's probably wrong) was even if I have some failure with fuel pressure, the primer will help. It stays running, just can't get the darn thing to start up. It's used only for ice fishing.

Just to confirm Leech, the vent lines identified in the pic's above SHOULD NOT be tampered with...e.g. used as a primer line?

Thanks

Well if you have good compression and spark there's only one equation left.  To much fuel-flooding, or not enough fuel starving.  Let us know how the primer add on works?   

[LPS]

Have you tried squirting gas into the carbs?  Or starting fluid?

[Pulleye16]

UPDATE:

Well, she started but it was still harder than it needs to be. I have NOT installed the primer yet, probably will wait until summer.

That said, I think you guys may be right. I wasn't able to run it hard after the carb cleaning this fall but she does bog down slightly when giving her full throttle now so I think i need to redo my carb cleaning again. :( Guessing there's still some debris or dirt lodged somewhere. Bummer

This time I'll buy the kits and replace the replaceables.

I also checked spark and that's also good.  So in review:

Spark good
Compression good
New fuel lines and filters
Adjust correct throttle and idle
Cleaned carbs
New drive shaft and bearing
New crankshaft bearing
New speedo key
Adjusted drive chain and replaced oil

Things to do:
Reclean carb and replace gaskets and seals
Adjust choke cable

[Boar]

Take a metel coffe can, put carb in it. Submerge with carb cleaner, bungie a palm sander to the outside of can. Turn on and hang for as long as yu think, vibration And sound cleans into smallet of places

[glenn57]

i helped a friend of mine clean my carbs, basiclly how boar explained it expect the palm sander thingy. but he does have a parts cleaner.

after my ski-doo basically sat for 4-5 years without even running it i decided i was going to keep it at the cabin, so i brought it to a guy that does that kinda stuff up there, he replaced the carb with a kit. runs like a champ. now i dont add no stabilizer etc.......non-oxy gas, a bit of starton and sea foam and i start in every time i'm at the cabin.

its your sled, but IMO maybe its time to do a new carb kit.........things wear out!!!!!!

[Boar]

I only use startron. Nuthin else

[Leech~~]

UPDATE:

Well, she started but it was still harder than it needs to be. I have NOT installed the primer yet, probably will wait until summer.

That said, I think you guys may be right. I wasn't able to run it hard after the carb cleaning this fall but she does bog down slightly when giving her full throttle now so I think i need to redo my carb cleaning again. :( Guessing there's still some debris or dirt lodged somewhere. Bummer

This time I'll buy the kits and replace the replaceables.

I also checked spark and that's also good.  So in review:

Spark good
Compression good
New fuel lines and filters
Adjust correct throttle and idle
Cleaned carbs
New drive shaft and bearing
New crankshaft bearing
New speedo key
Adjusted drive chain and replaced oil

Things to do:
Reclean carb and replace gaskets and seals
Adjust choke cable

If it's bogging at full throttle, she might be set a little lean.  Also, you might want to try spraying some carb cleaner like Gumout around the carb boots and gaskets and that crankshaft bearing to see if it picks up speed. If so you might have an air leak.

[glenn57]

Good ideas leech!!👍

[Pulleye16]

fun fact...I just read somewhere that MN has a "collector registration" unlimited use for sleds 25+ years old. Well, just so happens my registration expires so I may look into this for next season, considering my sled was made in 1998, I just make the cut! I think it costs $8.50 (w/fees included) and is good for the life I own the machine.

I can't take it on any grant-aid trails but I think its good for anything else..

Anyone ever buy or use this permit? Any issues with it? I just use it for ice fishing so it seems like a no-brainer....

[Leech~~]

If your just using it for ice fishing you maybe good!
You can alway check trails you may ride to see if there are any Grant-in-aid sections. Lots of trails I have riden have them and it's hard to proceed on the route without using them.