00 Mxz 700 Won't Start [Archive] - Snowmobile World : Your #1 Snowmobile Forum

: 00 Mxz 700 Won't Start

01-16-2004, 04:56 PM
I have a 2000 MXZ 700 and over the summer when it sat for about a month it would take a good 10 or 12 pulls to start it and in the winter when it hadnt been run for a few days it would take about 4-6. When it had just been run it only took 1 or 2 to start it. I pulled it out of the garage yesterday after it sat in there for about 2 or 3 weeks and it wont start. I pulled the crap out of it. The plugs were a little black and slightly wet so I put new ones in. Still wont start. I just remembered I read something about trouble starting sleds when they are pointed downhill, which I was. Is that something that is true for me or was that only for sleds with a primer?

This happened once before when the plugs were bad and I had a friend come over and he took out the plugs, pulled the crap out of it with the plugs out and switch off, then sprayed a little ether in each cylinder and put new plugs in and it fired right up. When it runs it runs great. Does this sound like dirty carbs or something else?

gravy davey
01-16-2004, 05:53 PM
After a sled sets without being run at least once a week the fuel evaporates from the carbs.Take your plugs out and dump a little fuel in the motor it should fire.

01-16-2004, 11:48 PM
But the plugs were wet. That means it was getting fuel, right?

Do dirty carbs cause the plugs to foul often? I think I only put about 50 miles on these plugs and they are black. Mostly farm field riding.

01-17-2004, 12:30 AM
Are you getting spark? Pull the plugs and w/ the spark plug boot on, hold the spark plug to the motor (might want to use a stick to hold it) and see if you are getting spark.

Also, is the headlight illuminating at all when you pull it?

01-17-2004, 12:53 AM
I'll check that tomorrow. I made the mistake of holding the boot once and my hair stood up. LOL

01-17-2004, 10:31 AM
Originally posted by CamaroDave@Jan 17 2004, 12:30 AM
Are you getting spark? Pull the plugs and w/ the spark plug boot on, hold the spark plug to the motor (might want to use a stick to hold it) and see if you are getting spark.

Also, is the headlight illuminating at all when you pull it?
if your getting spark its, in your fuel system..

if your sk-doo dont start.. check for spark first!!!!!!

01-17-2004, 12:25 PM
How cold is it when this happens??

You could have moisture on the impulse side of your fuel pump.

I had that problem and had to use a heat gun to unthaw the fuel pump.

Moisture will get into the diaphram on the fuel pump, no in the fuel, just the diaphram. You can pull all day and not start the thing unless it thaws out.

01-17-2004, 01:35 PM
It's kept in the garage and thats got a minimum of 45 degrees (F).

I checked for spark and its got it. I looked at the headlight and I didnt see it glow like I have in the past. What does that mean?

01-17-2004, 02:06 PM
Hey after mine have sat awhile sometimes it helps if you give it a blow....job....

let me explain that...the fuel pumps on snowmobiles are a vaccum type... so when you pull and pull you are creating vuccum to get the fuel pump started..and fuel up into the carbs...I have discovered if you put your hands around the gas tank filler and make a little hole in your hands and blow some air into the tank it helps the fuel getting to pump and into the carbs...which in terms you have less pulling...

But make sure you do have spark :blush: :unsure: :!:

01-17-2004, 03:59 PM
Upon closer examination...

Spark is good. Plugs are wet.

I shot a little starter fluid in the cylinders and it kicked for a sec and then died. Then nothing. I did it again and it did the same thing even tho I caught the throttle in time. Something is not right. Last time I had it out everything was fine. Nothing weird. As I was pulling, my dad noticed smoke coming out of the top head plate (not sure what its called) right in the middle. Something tells me thats not normal. I also found pieces of what looks like pink fiberglass insulation in the bottom of the belly pan. I"m not sure if thats part of a gasket that might have blown out or something a mouse dropped off. I'm not sure what the gaskets look like or whats up in the head.

I have stopped trying to start it and I'm gonna give an old friend a call that works at the ski-doo dealer.

01-17-2004, 05:25 PM
Alright, had my friend stop by and he closed the gap on the plugs a little (0.025) and it started on the third pull.

Couple questions:

If the gap was too big, it would spark in open air but not down in the cylinder. If it was not sparking in the cylinder would that cause the head light to not glow a little or is the head light run off of something else and has nothing to do with actual spark?

Is there a fuel shut off on the 00 MXZ 700's? I have not been able to find one and neither has anyone else that has looked.

As far as flooding while sitting in the garage, this is what I have thought of. Tell me if it makes any sense...

Since I dont shut the fuel off when trailering, I think it may have flooded when I brought it home last time. Everytime I trailer it I always run it and get it warm before I put it on the trailer and then it starts right up when I get where I'm going. Then when I come home I pull it off, start it and drive it in the garage. this past time I just backed the trailer right in the garage and left it. Could it have flooded while trailering and then since I didnt run it right away the gas sat in the carbs and went bad?

I still dont know why I see smoke coming out of the head. I'm going to check the head bolts and make sure they're tight. Its coming from the cylinder closest to the belt. What is required to replace that gasket? Is it as easy as it looks? Just take out the head bolts and put a new one in? (It cant be that easy)

01-18-2004, 08:10 AM
It's not a real good idea to use ether on them. If you spray just a bit of fuel into the carbs with the throttle held open and it's still hard to start check your reed valves to see if the rubber is coming off the cages. You have symptoms of bad reeds.

01-18-2004, 11:21 AM
Also check to make sure the fuel is still good. I ran into that problem before.

01-18-2004, 12:38 PM
What is required to replace that gasket? Is it as easy as it looks? Just take out the head bolts and put a new one in? (It cant be that easy)

Don't just pull the head bolts out. Remember this is a liqiud cooled engine so you would first have to drain the coolant down. There is only an "O" ring around the top of the cylinder, no gasket. If this "O"ring was leaking you would be getting coolant into the cylinders and if the seal around the head cover was leaking you would be getting coolant leaking externaly. As far as the plug gap, I also have a 00 mxz700 and gap the plugs to 18 thou. as per Ski-Doo service bulletin. if the gap is too big this could happen. I also agree as stated above that you could have reed problems. I don't know what to make of the smoke coming from the head, is it possible that you are seeing exhaust coming up from a leaking exhaust manifold gasket? You need three things for this engine to run 1 spark, 2 fuel, 3 compression.

01-18-2004, 05:11 PM
Would it be wise to run stabil all season long if I only ride it a few times a month?

In order to check the reeds the carbs need to come off, right?

Here's a picture to show you where I see the smoke coming from. The arrow indicates the direction of the smoke. It definately appears to be coming out of the circled area. Next time I have it out I will take a much closer look while its running because I have seen small amounts of smoke coming from that area in the past but I just passed it off as being a small leak in the exhaust.