Cj5 304 hot start

[74trs]

I have a 74 CJ5 with a 304. Starts right up when it is cold drive for a while get the temp up usually runs about 165-170 degrees. Hard to start when hot almost like there is no spark cools down starts right up? Has MSD ignition checked that per manufacture trouble shooting guide checks out ok. Replaced the coil. Could it be a bad diafram in the vacuum advance? Any suggestions would be appreciated.

Thaknks

 

[SteelHeadz]

Sounds like you need to adjust your timing just a little bit. .Mine use to do that even with the HEI distributor. Vacuum advance should not be engaged at startup or idle.

 

[74trs]

Thanks Steelheadz I will give that a shot. Do you think it could possible be vapor locking?

 

[SteelHeadz]

Yup, definitely a possiblity. One of the things i changed on that note is re-route the fuel line from the bottom of the driver floorboard to the center trans tunnel and up to the firewall. This keeps the fuel cooler before it gets to the carburator as opposed to it's original location where the exaust manifold heats up the fuel line after a while of driving and gets a hard start from a hot soaked engine.

 

[scjeep4.7HO]

Tell you what. After I done allot of the performance stuff including moving the battery to the back of my grand cherokee. I tried going to a optima red top. It did help but this summer I have had more issues and have tried other thing. I went from the 2 gauge battery relocation kit to a 4/0 cable which is really really thick and it did help some but then realized my negative cable was the issue through allot of trial and error. next time it is hard to strart just try grounding the neg cable with just the neg of the jumper cabke and see if it starts. if not try jumpin yourself that how I narrowed it down.

 

[yo momma yj]

next hot start, drop 1/2 teaspoon of raw gas in the intake and see if it hits...if so, it's fuel delivery,

if it doesn't hit, look at spark and do a compression check to make sure you don't have a temp expansion thing at the valve seats giving lower compression. (I'm assuming this is hydraulic lifters..if solid lifters check the clearance)

after that, check the amp draw on the starter and grounds...it's possible there's low voltage available for the ign. due to demand from the starter. old grounds are notorious gremlins.

gas in the intake is the quickest way to determine where you have to look next.