[ballpark]

Hey, a friend brought up an old 70 somthing Jag, single carb, dual cylinder, premix, sled and we can't get the thing started.  We drained the gas and put in fresh stuff (properly mixed), changed the plugs, and pulled a thousand times. The head light comes on, but it seems like its getting no spark.  Like a kill switch is stuck on kill.  What should be my first steps twords getting this started. How can I test the spark?  This thing ran eariler this year, but at high speeds would bogg out and loose all power, if you waited a second and slowly accelerated you could get up to speed for awhile.  At the same time that it ran it was still really hard to start.  Maybe the carbs need cleaning?  Thanks for all your help in advance.

 

[Auggie]

Well, I am not sure what ign. sys. they had in the 70's, closed or open. Anyhow try this. There are four wires coming out of the eng. by the rewind that lead to a four wire connector. Unplug this connector and check for spark. If you have spark then that sled has an open system. If there is no spark then useing a jumper wire jump between the black and brown wires in the four wire connector on the eng. side. If you still don't have spark then unplug the three wire and single wire connectors and clean the connections and squeeze the female connectors to tighten them up. Also clean the four wire connector. Plug the three and single wire connectors back in and check for spark. Try this and get back to me.

   -Auggie-

PS: It would be helpful to know what year the sled is (first two numbers of the serial no. is the year) and what size the eng. is? Is it fan cooled or free air.

 

[ballpark]

Ok, thanks for the start. First of all its a 1978 Jag Spirit 3000. I couldn't find the size of the engine but it said  bore and stroke are 60mm.  Its free air cooled.   Ok, when I seperated the 4 pin connector I had spark in both plugs. What is my next step. Thanks for the help!

 

[NHIcegator]

in my experiance with old cat motors,mostly kawasaki types
spark and gas good still won't start= bad crank seals
but I'm not that familier with suziki motors so that theory may not apply in your case

 

[Auggie]

Ok, so you got spark. Good. Now spray a small amount of carb & brake cleaner (or gas) into each cyl. and install the plugs and wires. Try to start the eng. but remember that you have the four wire connector unpluged so you will have no way of shutting down the en. So the sled won't go through the the door always raise the track off of the ground. Don't run the eng. with the drive belt removed. Get back to me.

   -Auggie-

Ps: The Jag 3000 is a 339 cc eng.

 

[mopar4u]

Not sure on specifics on your sled but...Definately go through the carbs (especially if it is a diaphragm carb), probably a good idea to change all gas hoses to eliminate the possiblity of the carb sucking in air.  When you put some starting fluid in the cylinders, did the sled fire and quit, or could you still not get it started at all?  Is it as simple as changeing and gapping new spark plugs?  Good Luck

 

[adam728]

I would guess that the carbs need a good cleaning. It is easy enough to do, and if it doesn't work, at least it doesn't hurt.  A compression check would be a good idea too.

 

[ballpark]

Hey sorry its been so long.  I have been really busy fixing my other sled but the other day I looked at the jag again.  Sprayed some wd-40 in the cylinders and it didn't do much, so I did it again but used a lot more this time.  It started!  Finally,  plugged the kill harness back together and it died.  Somthing was wrong with one of the swittches.  Oh, and when we shut it down, it was really hard to start again.  After looking more we found a hole in the gasket between the carb and the block.  So for an experiment, taped it up, and it started great.  Thanks for all your help!

 

[ballpark]

Hey sorry its been so long.  I have been really busy fixing my other sled but the other day I looked at the jag again.  Sprayed some wd-40 in the cylinders and it didn't do much, so I did it again but used a lot more this time.  It started!  Finally,  plugged the kill harness back together and it died.  Somthing was wrong with one of the swittches.  Oh, and when we shut it down, it was really hard to start again.  After looking more we found a hole in the gasket between the carb and the block.  So for an experiment, taped it up, and it started great.  Thanks for all your help!