JD 600 help

Tinwood · Post by **Tinwood** » Fri Dec 12, 2008 3:40 pm

First had it running last weekend for 3 minutes used starting fluid for it to fire. Now anyone willing to help I appreciate it. Here's what i've done so far cleaned fuel tank and filter. Replaced all gas lines and had carb rebuilt walbro 32a. New plugs ngk gap .020 have good spark not a mechanic so I could be wrong. Today I checked the points and the gap was .014 they look good and flat. The original compression test was up to 145 so after running last weekend checked it again one pull 120 2nd 140 3rd 145 and held both cylinders within 2 psi. So I was getting tired of pulling and decided what the heck hooked up a battery and she cranked over like a mad man but not a single sign of firing. Gas is the next question being new to snowmobiles gas was coming out of the exhaust after turning it over. The cylinder top seemed dry yet and they do have some black deposits or corrosion on top. Thought about the kill switch (out) is for run (in) is off correct? Carb is set 1 turn out low idle high is 3/4 turn out.
Lights all worked with battery and key in run. Any ideas would be helpful what do I ckheck next?

400brian · Post by **400brian** » Fri Dec 12, 2008 4:07 pm

Please read " trouble shooting your sled" in the FAQ section.

wycrumb · Post by **wycrumb** » Sat Dec 13, 2008 1:16 pm

Ok, you have seen talk of engine seals, they should be changed, put new seals and gaskets in the whole engine, dont pull the pistons out of the jugs, it is possible. Try about 1 to 1.25 turns out on the screws. These can be adjusted when it is running, have it on a stand and tune the high screw fist, then once it is warm, tune the idle screw. If you are getting spark that is good and you can forget about the kill switch and the ignition switch, they are all fine. When you were turning it over did you check the plugs afterward? were they wet? if so you might be getting too much fuel. If they are not wet then you are not getting gas so you need to make sure it is pumping gas. If they are dry you can put a very small amount of gas in each cylinder and it should fire up. another thing you can do is put your hand over the back of the carb for a sec, it will help it suck in gas to get gas into the carb and cylinders but it will also kill the sled when it is running. I put a primer on my 400, that way I rarely need choke and it starts up no problem. you said the heads (cylinder tops) looked black, does this mean you removed them? If so you will need new head gasket before you try get it running. Try this with the airbox off, the muffler on and make sure the muffler is clear if mouse nests and the such. Good luck and try using the FAQ after this if you can, these guys like to help but only after you have tried to help yourself first.

Tinwood · Post by **Tinwood** » Sun Dec 14, 2008 10:03 pm

This maybe my last update on my jd 600. Tried eveything I could think of to get it to fire compression good spark ok plugs have some fuel on them after trying to start. What the heck sprayed starting fluid in spark plug holes did here a little rumble. It ran for 2 minutes or so and sounded so great a week ago. What is the weakest link in the ignition system? Exhaust is clear no sign of oil or gas around gaskets at all. Any help would be great or I have to give up for lack of money.

mikehjd · Post by **mikehjd** » Mon Dec 15, 2008 3:21 am

I had the same problem you are having, I tried everything even 2 different carbs. When I was just about to give up I tried one more carb and it runs fine now. Don't give up on it.

400brian · Post by **400brian** » Mon Dec 15, 2008 4:06 am

First off, ditch the starting fluid.

If you have spark and compression, it should run if you spray a bit of premix into the carb throat with a spray bottle.

If it will not run that way, you likely have ignition issues. Corroded points typically.

Tinwood · Post by **Tinwood** » Tue Dec 16, 2008 12:22 am

thanks for all the info will try again tommorow. What would be the best spark plug if the ignition is weak? Also how to get fuel out of the crankcase suck it out or blow it out? Don't want to give up if since there are good signs of engine being sound. thanks any other ideas let me know

JDT · Post by **JDT** » Tue Dec 16, 2008 12:33 am

Do not blow or suck excess fuel from the crank. You risk distroying the seals.
There are two small drain plugs at the very bottom of the case below the intake manifold.
A 10mm socket will get them out. Lift the front of the seld up and let it sit and drain if need be.

Tinwood · Post by **Tinwood** » Tue Dec 16, 2008 12:44 am

thanks jdt

DLDeere · Post by **DLDeere** » Tue Dec 16, 2008 1:30 am

This may seem like a dumb suggestion, but sometimes we overlook the obvious. You said you pulled plugs and and checked for spark and had good spark. Did you get the wires back on the right plug? If they're turned around, there's no way it will start. Maybe try switching them and see what happens.

S_Kyle · Post by **S_Kyle** » Tue Dec 16, 2008 1:54 am

I did that once. But I made the mistake of taking it to a guy for help

. Turns out that the short wire goes to the far plug on a merc

Scott

Tinwood · Post by **Tinwood** » Tue Dec 16, 2008 1:55 am

thought of that DLDEERE thats not it will try a few things and post back tommorow

JDT · Post by **JDT** » Tue Dec 16, 2008 1:56 am

Sometimes PSO's switch the red and white coil wires around also. All it will do is pop and backfire then.

Tinwood · Post by **Tinwood** » Tue Dec 16, 2008 2:01 am

what spark plug would produce the best hottest spark if the system is weak?

JDT · Post by **JDT** » Tue Dec 16, 2008 2:12 am

Best to fix the real problem , not come up with a bandaid for the symptom.