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Discussion Starter · #1 ·
About 3 weeks ago, I bought an '96 ZRT800 with reverse and electric start that hadn't been run for two winters. Supposedly, the owners took it out for the '08 riding season, it wouldn't start, and they put it away.

Since we got some more snow this year (lower midwest), they drug it back out and took it to a "mechanic" to figure out why it wouldn't run. He told them that the compression was low (65-65-70) and would need a total overhaul. Instead of putting money into it, they put it on eBay as a parts sled. Before I bought it, the seller's agent, the "mechanic", told me that he knew the electric start worked since that is what he had used to do the compression check.

I ended up buying it thinking that it was going to need a total overhaul. Before I started anything though, I decided to run a compression check on it myself. Well, lo and behold, it had 125-125-128 after 3 or 4 pulls of the rope with the throttle held wide open. While I was doing this, I had left the spark plugs out of the adjacent cylinders. Huge amounts of fuel sprayed out of each hole whenever I pulled it over...even if I wasn't holding the throttle.

Someone had also decided to steal the spark plug wires from the double coil so I found another one along with a service manual on the auction site and bought both.

Because it seemed to be flooding really badly, I decided to pull the carbs and clean them. The floats were actually stuck in the bottom and just about wouldn't budge even with my finger pulling on them. Some of the passages were actually full of some green gunk that required a tiny drill bit in my hand to even get through it. A couple of cans of carburetor cleaner and a few hours later, I had them as clean as I could get them.

When I had taken them apart, I made sure to check the existing pilot air jet screw settings and it was 1 1/4 turns from the bottom. I didn't mess with the knurled screw on the side of the carburetors at all.

Since it hadn't been run in a long time and the cylinders had flooded with raw fuel, I put about a 1/2 oz of two-cycle oil down each spark plug hole and pulled the cord about 7 or 8 times to make sure that the walls would get sufficient coverage before I started it for the first time. I also went ahead and put mixed fuel in it just be sure. BTW, I replaced all of the fuel and vacuum lines while I had it apart.

Ok, so today I got it fired and running. I shut it off and restarted it several times to purge any air bubbles that were trapped anywhere in the fuel system.

So now when it is running, it is idling really fast. There is no slack in the thumb throttle but I don't remember if there was to begin with or not. I didn't mess with any of those adjustments when I had the carbs apart.

Also, when I want it to start, the choke doesn't seem to make a difference. It seems to want to have the throttle just cracked and then it will fire. It also has backfired a couple of times before it started as well. When you go to goose the throttle, it picks right up off of idle but I didn't want to jump the rpm's too high.

What do I need to do as far as setting the carbs since I am sure that is the direction that I headed? Are my basic settings the problem?

Any helpful hints or suggestions would be very much appreciated.

And one more thing, the tachometer doesn't work so I have no idea what the rpms it is idling at. Getting it working is going to be one the priority projects.
 

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the throttle should have a tiny bit of slack in it.

as for the starting issue, make sure the choke slides are closing all the way, it doesnt take much debris in there to make them leak a little extra fuel. i had that issue in a jag. i needed to really scrape the bottom of where the choke goes with a small screwdriver to get the hardened varnish out.
 

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I wondered why your PM's stopped haha. Glad to see she is up and running!!

Are all the passage ways thru the carbs cleaned out? That green gunk was varnish from gas. Sounds like your idle is turned up to high. Are all the screws at their factory settings, Oh wait, you said you did not turn that one.

You can use a drill bit to get them very close. Just put it in the intake side and adjust all the throtlle slides to bottom out on the bit.
I think I used a 3/16 on my ZRT.

And ilive4snow700 is correct on the choke plungers. I did a write up on them located here
http://www.snowmobilefanatics.com/forum/topic/85294/display.aspx
 

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96 sleds have round slides. Make sure all of your cables are adjusted correctly. The throttle should open all the way and return all of the way. Easy adjustments. Like previously mentioned, make sure chokes are not stuck or stuck open. The choke lever should be just a little loose. Also, make sure the oil injection line is adjusted correctly. The oil pump shouldn't start to move until you crack the throttle an 1/8th to 3/16th of an inch. Sounds like after a couple of adjustments you'll have a good running sled. Also, bypass the TSS switch.
 

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Discussion Starter · #6 ·
When I was cleaning the carbs, I did clean the choke slides very well but I may have neglected to clean where they go in the top of the carbs. To be honest about it, I don't remember.

The TSS has been bypassed...the wires coming from the throttle side of the handlebars has been cut and a wire nut installed on the handlebar side of the plug at the base of the handlebars. To be honest about, it would be nice to have a functioning stop by my thumb. That is something that is going to be replaced soon.

What about the pilot air screw being turned out 1 1/4 turns? What will that do to the mixture?

Thanks for the info on adjusting the carbs. I am going to have to try that this morning.
 

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Whoops! I only read the first sentence of what I posted from my search result. I didn't know that post was for flatslides. Yep the 96 ZRT has roundslides and that is what I ment to post about. I revised it in case anyone searches for this in the future haha.
 
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