Cranky Hurricane

I have 64 CJ with the trusty F134. It has run like a sewing machine since purchased. Recently, it has been cutting out when reaching full operating temp (180 +/-) and will not restart until cool. Still has spark just after stalling. Carb and coil cool. Fuel filter was empty but test shows 4 lbs of pressure. All connections tight. No sediment in the fuel tank, pickup is clear. Fresh ballast installed, no change. Can’t figure it out. I about to start changing parts starting with the fuel pump…. Anyone seen this in the past?

 

Static pressure is only half the test for a fuel pump. FSM also specifies verifying the flow volume.

Full "pressure" can be provided by a pinhole too small to allow any meaningful flow.

Another thought - don't be focused exclusively on the "warmed up" aspect. Could be coincidental. (For instance, if your fuel tank is not venting the vacuum takes time to develop. Tried loosening the gas cap?)

 

Glenn, thanks for your quick response. Checked the fuel pump and line after a stall this afternoon, both cool to the touch. No bubble on this pump, but it looks like it might be time for an upgrade. I have been thinking about swapping in a clear filter just before the pump to be sure all good up to there. I’m getting a spark, but any chance it might be the ignition module in the distributor. I understand the Omix Ada parts can be unreliable.

 

Wow, thanks for the feedback everyone, much appreciated. Yes, went through the vacuum possibility, no leaks except for the fuel cap (as it should be?).

Interesting point on the fuel pressure, feeling like the pump is the issue. Point taken on the “warm up” observation, easy to fall for it given the condition is so consistent.

 

Electronic ignition? All bets are off.

Put the points back in and try it.

 

Howard,

Same gas station, but I haven’t fueled it since mid-summer. The mowers seem to be running find though….

 

Could also be condenser or coil. Even though it has spark, it could be weak

But.... from the symptoms it sounds more like a fuel pump or vapor lock. How freah are the hoses in the fuel system? Old hoses can leak air ancause issueses.

 

Yea, well the points are long gone. I regretted that move after the first time the distributor failed on me. Lesson learned. I’m not keen at throwing money at it, but I’ll be in the market for a points style kit if a new fuel pump doesn’t solve the problem.

 

The hoses are fresh, replaced them when I changed the filters. I swapped a spare coil I had lying around, but that could have been weak. Runs fine until it stalls though.

 

Hoses ??

The only hose that should be in the fuel system is the flex hose from the hard line on the frame to the pump. Hoses elsewhere, such as rubber fuel line with screw clamps connecting to hard line are a likely source of air leaks in the system and that would explain the empty filter.

 

Next time it dies, immediately see if a shot of gas or starting fluid into the carb will get it to fire. Might help differentiate between fuel and electrical.