Posted by Marty [172.71.150.51] on Sunday, August 13, 2023 at 21:02:45 :
So my 48 is having a very strange issue. So for the past year now it's had a strange miss. Starts perfect with 6 volts on the second revolution always even when stone cold. So when I first brought this truck home I drove it up the road on the freeway flat out & it ran great getting up to the freeway but once on the road & foot to the floor under load it starts missing. Sporadically'like not all the time. So I take my foot off the gas'still wanting to miss but I make it back home. Start hunting for the problem'wires tight, everything looks good. So I had a spare distributor I stripped down & cleaned up. All new parts. Points condenser, rotor, cap. Everything looks great. Pull it completely apart, check the ground, put it all back together, swap distributors & set timing. Engine running great. Repeat'same result. Hmmm'gotta be fuel & the pump looks nasty so I'm starting there.
So I haven't replaced the fuel line however I did replace the fuel tank when I first got the truck & it's perfect inside.
So'I buy a Carter pump & install it the other day along with the short flex line from the fuel line to the pump. It has the heat shield installed & the engine shrouds (which are a pain dealing with the pump & right in the way however they're back in there as they should be.
Figured I got it this time because the pump looked original. Take it to the car show yesterday'no missing while driving it maybe 15 minutes including on the hwy. so after the show wifey wanted to go to Costco & I decided we'd take the PW before loading it up. Get a couple miles away & it starts doing it again! So I limp it to Costco & make it there.
We leave & it immediately starts doing it more violently than usual & stalls. Crank for 15 seconds & pull the choke'starts'running bad & stalls. Put choke in. Crank 15 seconds choke in choke out nothing. Coast down a 3 mile hill on the Trans Canada hwy to within a mile of my truck & trailer & im thinking I gotta walk & go get it. I pull the choke & it fires up! I limp back to my truck & trailer & get it loaded.
So today, car show #2. We trailer it to 5 miles away from the show & unload it. Drives to the show fine. Start it up after the show'starts fine.
Now last night I was chatting with Steve Kagi & we were wondering if it could be the coil? So I find a coil on my way home from the show. When I get home I pull the coil & it's definitely original from new. It's an Autolite & it has these cool ridges that help line up the coil on the mounting bracket. The trucks just so original I believe it's original from new. No visible damage or leaking. Change it anyway & double check the wires'all good.
Fires up first revolution'running perfect. Take it up to the hwy'hammer to the floor in 4th gear'going great! Starts missing again.
Slowed & brought it home.
So'I've never had the carb top off but just seems weird it runs great when cool anyway?
Any ideas? I'm going to have a closer look at the fuel line. It's not leaking fuel or anything visible but it sure seams like a fuel issue to me. I need to double check the swell but I don't think it's that or timing. It doesn't make sense.
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