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Member Since 11 Jul 2017
Offline Last Active May 19 2018 06:08 PM

Topics I've Started

Headlights won’t turn on

13 April 2018 - 07:59 PM

So I was going to drive my 1978 620 into town to get gas tonight, and I went to start my truck and it wouldn’t crank. I tried to headlights to see if I had battery power, and they didn’t come on. I disconnected the positive lead from my battery for a while, then reconnected it. My truck then was able to crank, but my headlights won’t come on. I already checked the fuses in the cab, and they’re all good. I also removed the headlamp fuse and put it back in to see if the contacts were dirty, but it didn’t help. The PO rewired part of the headlight circuit. There is a pullout switch to turn them on and off, and a click button type switch by my feet for the brights. I can add pictures if that doesn’t make sense.

I’m not really sure where to begin diagnosing. Any info is appreciated

Weber running too lean, can’t adjust enough?

02 April 2018 - 08:04 PM

Hello, I have a 78 620 that I just recently started daily driving. I’m trying to get the air/fuel ratio correct, and right now it’s running too lean. The plugs are whitish, and it hesitates when throttle is applied quickly. I have been trying to richen it up a bit using the fuel mixture screw, but I’m a bit confused. I get the truck running, then turn the screw in until it starts to drop down in RPM, then I back it out and the rpms come back up, and I’m supposed to keep backing it out until it drops down again, but no matter how far I back it out it doesn’t ever drop back down. Does this mean I need to rejet it? I’m not a carb expert by any means. Also, which jets would I be replacing?

Best muffler?

29 March 2018 - 12:08 PM

I have a 78 620 with a Weber that I’m wanting to make sound a little better. I eventually want to put a header on it and maybe bump up the pipe size a little, but for now I’m thinking I’ll just replace the muffler to add a little sound. I’ve heard mixed opinions on cherry bombs. I’ve heard the thrush turbo muffler is good. What about just replacing the stock muffler with a piece of straight pipe? Would that cut down on back pressure too much? Just want some advice.

Is there any alternative to new shifter bushings?

04 March 2018 - 11:11 AM

I have a 78 620 that is in need of shifter bushings. I know that they aren’t very expensive, but I was wondering if there’s anything else I could use as a substitute. I was thinking washers for the side to side movement and maybe some kind of plastic on the shaft part? Any ideas would be appreciated!

78 620 horn diagram? Horn not working

11 October 2017 - 07:01 PM

I'm wanting to get my horn working. Im not sure where to start. I did a little research and found that the relays go bad pretty often, but couldn't find anything 620 specific. I need to find out where the horn relay is. I already checked the fuse and it's good. Just not sure what to troubleshoot. Any advice is appreciated