I think I finally solved some mysteries on this machine.
Last summer I did a full top end, including new jugs on it. Ran great for about 250-300 miles and then went back to what it was doing before. After it gets hot, it is really hard to start and when I checked compression (while hot) I had 90 in both cylinders.
Well, I believe that mystery was related to the weak fuel pump. I put new rings on the pistons and after putting it all together and letting it run, while idling it just died. I notice the fuel line is empty. So I pressurize the tank to force fuel back into the carb and then started it again. Watched and as long as it was on high idle or faster, it could pull fuel through. As soon as it dropped to normal idle, the fuel line would empty out. I'm guessed the fuel pump was weak and maybe running the whole thing to lean.
I put a new rebuild kit into the fuel pump and I could instantly see a difference. Fuel pumped much faster into the carb.
The other mystery was every time you turned a hard right, the thing wanted to die. Obviously electrical, but I could not figure it out. All the wires were good and double insulated around the steering column. Nothing getting pulled that I could see. Then I figured it out, when the bars were turned to the right, it was pushing connectors hard against the key switch, causing something to short out. I just re-routed the wires and pushed the connectors out of the way.
Last summer I did a full top end, including new jugs on it. Ran great for about 250-300 miles and then went back to what it was doing before. After it gets hot, it is really hard to start and when I checked compression (while hot) I had 90 in both cylinders.
Well, I believe that mystery was related to the weak fuel pump. I put new rings on the pistons and after putting it all together and letting it run, while idling it just died. I notice the fuel line is empty. So I pressurize the tank to force fuel back into the carb and then started it again. Watched and as long as it was on high idle or faster, it could pull fuel through. As soon as it dropped to normal idle, the fuel line would empty out. I'm guessed the fuel pump was weak and maybe running the whole thing to lean.
I put a new rebuild kit into the fuel pump and I could instantly see a difference. Fuel pumped much faster into the carb.
The other mystery was every time you turned a hard right, the thing wanted to die. Obviously electrical, but I could not figure it out. All the wires were good and double insulated around the steering column. Nothing getting pulled that I could see. Then I figured it out, when the bars were turned to the right, it was pushing connectors hard against the key switch, causing something to short out. I just re-routed the wires and pushed the connectors out of the way.
My 99 Jag 340
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