JDX8 problem

JDman21 · Post by **JDman21** » Sun Jan 01, 2006 3:16 pm

I have a 1973 JDX8 I swapped out the old engine because it doesnt run well. Think the crank seals are bad. So I put a spare engine in. I put new gas in too. It wont start. I can spray gas into the carb and it will run till that runs out. It doesnt seem like the carb is getting gas. I'll push the throttle while I get it running and it just dies. I'm thinking maybe the fuel pump? Carb is very clean. Any ideas. carb is a WDA-33, is that right, my book says different.

Thanks

Danzig · Post by **Danzig** » Sun Jan 01, 2006 10:22 pm

I think the carb is correct however a WDA-34 is what I believe is called out per book specs. I had a problem with mine doing the same thing, the pulse line was not there and the fuel pick up hose in the tank fell off into the tank.

JDman21 · Post by **JDman21** » Sun Jan 01, 2006 10:55 pm

What is the pulse line? I'm getting gas to the carb, I can see it in the lines and when I took the carb off there was a little gas in it, but not much at all.

Thanks

JDman21 · Post by **JDman21** » Sun Jan 01, 2006 11:48 pm

I forgot to add that when I squeeze on my fuel filter gas shoots up into the carb and out a side hole. Is that supposed to happen. The hole looks like its supposed to be there. Am I missing something?

Thanks

Post by **Matt** » Mon Jan 02, 2006 12:02 am

There should be 3 different pieces of fuel line connected to your carb.

1) The intake from the tank, in the center of the bottom of the carb.
2) The return line to the tank, offset on the bottom of the carb.
3) The impulse line, which is an angled fitting on the side of the carb, which connects to a fitting on the crankcase.

JDman21 · Post by **JDman21** » Mon Jan 02, 2006 6:38 pm

I got it to run, it was the pulse line. Now it doesnt stay running. I rode it and the only way to keep it running is to have it not quite all the way choked. Whats going on?

Thanks

Danzig · Post by **Danzig** » Mon Jan 02, 2006 7:16 pm

Get it good and warmed up and get it on blocks. Keep it running even if you have to keep spraying fuel into the carb by hand. Keep an eye on the fuel flow from the tank to the carb, watch for air bubbles also. You shouldnt see any air bubbles after a while of running. I ran mine sled like this for a week or 2 to trouble shoot what I was dealing with. I ran the engine up to where the clutch engages around 3800 RPM's and held it there, still spraying fuel in the carb by hand. I kept doing this it seemed like everyday for a week, I am not sure but I think my carb may have been gummed up over its 23 year sit stint. I changed out the plugs to Champions and this year went to the NGK's which helped me out considerably. After I had the sled running by hand for about a week, I then decided to tear down the carb completely, clean it and I reassembled it very carefully due to not having a kit for it. The next thing I did was reinstalled the carb and restarted it up, i then reset the air fuel mix screw on the low idle and estimated the high speed screw to be turned out about 1.75 turns out. After a little playing around, she fired up but not so well, I found the impulse line to be loose fitting and replaced it with another line and clamped it on the carb and engine. At this time I was up and running on the sleds own power, hand spraying was not needed. Then I noticed alot of air bubbles going to the carb, I found that the fuel pick up hose was not sitting in the gas but it was floating, I ordered a fuel anti-flow back valve and re-measured a new piece of fuel line and installed this in the tank. I have since been having minor problems with what seems to be a high speed miss problem only on fresh powder snow, the guys on here say to change out the spark plug wires next. As of now, no snow. But the sled had about 250 miles put on it this year and it will run 70mph. I have been riding it around the area where I live and it runs and I will say this, it is awesome!!.......The people who helped my on this site were awesome. I spent Alot of nights in the chat room with certain people who I will not state do to not wanting to miss anyone. This is a great sight, keep asking questions and you will learn and get your answers. I did!

JDman21 · Post by **JDman21** » Mon Jan 02, 2006 8:12 pm

I had it running again, with my hand on and off the carb to keep it choked. It was easier and quicker using my hand. I was just about to quit and I saw a fuel leak. So I looked at it and when ever I rev it up gas was spraying out the back. Probably need new gaskets. So where its leaking its probably sucking air and thats why it wont stay running. Anyone think thats it?

Thanks

400brian · Post by **400brian** » Mon Jan 02, 2006 9:23 pm

What you are seeing is certainly something that needs to be addressed.
Get a rebuild kit for your carb. Clean it thoroughly inside and out.
Check or replace fuel lines, clamp all connections. Check fuel pickup.
You're on the right track, read the trouble shooting FAQ.