Have you tried really advancing it? Like just keep going to see if it gets happier. Like better idle, better vacuum. Then worry about pre ignition later. Just a thought
Builds New project, 1969 fj40 (3 Viewers)
- Thread starter 6f40j9
- Start date
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pb4ugo
SILVER Star
Its sounds like there's something wrong with the carbs idle circuit or you have a vacuum leak.
There are 2 marks on the flywheel, a bb and a tdc mark. If your going to use the bb which represents 7* b4 top dead center(btdc) when its lined up with pointer in the window, adjust the strobe light function to 0 when using the bb.
The light doesn't adjust the timing, it tells where the timing is set. To use the strobe adjustment function you use the tdc mark on the flywheel. Adjust the light up or down until the tdc flywheel mark lines up with the pointer in the window. When they are lined up the # on the light is where the timing is set. Let us know what that # is.
There are 2 marks on the flywheel, a bb and a tdc mark. If your going to use the bb which represents 7* b4 top dead center(btdc) when its lined up with pointer in the window, adjust the strobe light function to 0 when using the bb.
The light doesn't adjust the timing, it tells where the timing is set. To use the strobe adjustment function you use the tdc mark on the flywheel. Adjust the light up or down until the tdc flywheel mark lines up with the pointer in the window. When they are lined up the # on the light is where the timing is set. Let us know what that # is.
6f40j9
SILVER Star
- Thread starter
- #644
Hmm.
I’m trying to understand, but I’ve got so many different tips rolling around in my brain.
At first I was trying to set the idle to 600, with the light set at 0* and the bb on the line. Then
I did try lining up the tdc line (set at 0*) and getting it to idle at 600 as well but that didn’t work either.
So I went back to the bb but at 10* (light set at 3), and trying to adjust the distributor and idle screw to hit anywhere in the 600s with it still running but I can’t get lower than low 800s every once in awhile.
Maybe I’m not giving it enough time in between adjustments.
I’m doing micro adjustments on the idle screw while watching the rpms on the light, then walking around and checking/adjusting the bb via moving the distributor. Then back over to the idle screw, turn it out until it almost dies (~8-900s) then go turn the distributor again to get the bb back on the line.
My whole process is probably wrong.
firemanj92
SILVER Star
FWIW, I'm at 14* and 650ish rpm, that is where my rebuilt is happy running. I've seen others up higher 21* so 10* just might not be enough.
6f40j9
SILVER Star
- Thread starter
- #646
Tried advancing it a bunch and still can’t get lower than 800s.
I really don’t want to waste any more money or time on this horrible carburetor. I’m aware there might be a vacuum leak as well but I can address that when I put a carburetor on.
My biggest regret with this truck was this whole situation from the start. It’s my fault, I was warned.
I’ve been on the hunt for a replacement carb ever since I installed this one, but I’d like to find one in kit form. I can’t be chasing around 15 different parts to make something work on my truck.
Guess it’s off to the classifieds again.
I really don’t want to waste any more money or time on this horrible carburetor. I’m aware there might be a vacuum leak as well but I can address that when I put a carburetor on.
My biggest regret with this truck was this whole situation from the start. It’s my fault, I was warned.
I’ve been on the hunt for a replacement carb ever since I installed this one, but I’d like to find one in kit form. I can’t be chasing around 15 different parts to make something work on my truck.
Guess it’s off to the classifieds again.
firemanj92
SILVER Star
I saw 3 x early carbs at Perry's Farm the previous year. (I picked one up with a date code 6/70).
6f40j9
SILVER Star
- Thread starter
- #648
The problem is, I don’t know what I’m looking at. They all look relatively the same to me. I’ve heard an early to mid 70s would be best, but there’s all sorts of brackets, riser, air filter top, etc that I need to change if I go that route. That’s how I ended up with my current carburetor-it worked with all my existing stuff.
I don’t mind changing all the parts, I just don’t have the knowledge or patience to piece it all together from different sources. I know it may sound lazy, but I’m trying to be realistic.
firemanj92
SILVER Star
" I know it may sound lazy, but I’m trying to be realistic." I get it. It's not being lazy but more cautious.
Next time you go, speak with Georg @orangefj45 or any of Georg's crew or Rob Tygart @landcrusher909 to get their advice if you see a carb that might work. I think you have plenty of pics for reference. I would make an educated guess after looking back at your carb pics it appears to be connected at all the same spots as mine so it may not have any funny business going on.
Some of the vendor's have no idea what they are selling and just there to make $$. I ran into this dilemma when I asked a vendor about a rear step (early vs later fj40's) and they had know idea what they had.
Next time you go, speak with Georg @orangefj45 or any of Georg's crew or Rob Tygart @landcrusher909 to get their advice if you see a carb that might work. I think you have plenty of pics for reference. I would make an educated guess after looking back at your carb pics it appears to be connected at all the same spots as mine so it may not have any funny business going on.
Some of the vendor's have no idea what they are selling and just there to make $$. I ran into this dilemma when I asked a vendor about a rear step (early vs later fj40's) and they had know idea what they had.
RodrigzCrzr
SILVER Star
I haven’t read your whole thread but have you checked your electrical connections. Anything around your dizzy? Points, Condensor, idle solenoid? Or even check the connections of your fuse block.
I had similar problems and I noticed a few bad connections. Bad points and condensor or coil.
I started from scratch and worked my way to the carb.
Sometimes it is not the carbs that is your issue.
I had similar problems and I noticed a few bad connections. Bad points and condensor or coil.
I started from scratch and worked my way to the carb.
Sometimes it is not the carbs that is your issue.
RodrigzCrzr
SILVER Star
Plug all your vacuum ports I.E brake booster, manifold, carb base ports, dizzy advance and take them out of the equation and plug them in one at a time.
I see you have a 69 fj40, you could have a vacuum leak at your 4wd actuator which is vacuum operated. And or the check valve at the drivers side. Anything is a possibility.
Get a vacuum gauge.
I see you have a 69 fj40, you could have a vacuum leak at your 4wd actuator which is vacuum operated. And or the check valve at the drivers side. Anything is a possibility.
Get a vacuum gauge.
RodrigzCrzr
SILVER Star
I had some bad connections on my fuse block cleaned them connections up and makes a a difference.There’s no vacuum running to or from the carb or distributor but anything is possible.
I can go through the fuse block, but it’s newer and everything else works as it should, there’s no electrical going to the carburetor. Good ideas, I appreciate the input!
RodrigzCrzr
SILVER Star
The electrical doesn’t have to be associated with the carb. It could make seem like it is the carb but comes down to being the ignition system. And that can throw you for a loop.There’s no vacuum running to or from the carb or distributor but anything is possible.
I can go through the fuse block, but it’s newer and everything else works as it should, there’s no electrical going to the carburetor. Good ideas, I appreciate the input!
RodrigzCrzr
SILVER Star
Your whole problem started when you adjusted your distributor! I say stay with that.
Check your points and connections. Even your black/yellow wire.
Check your points and connections. Even your black/yellow wire.
Last year when @MatthewMcD wS having issues getting his vehicle up to speed, I asked him to try my Weber carb I’d taken off of my ‘75 and see if it worked for him to isolate his troubles.
If you’d like, your are more than welcome to give it a go as well. It’s still packed up when Matthew sent it back to me. Try it for a week or so maybe it makes a difference, maybe it won’t. Worst case scenario… the cost of postage sending it back…. If you decide to…let me know. This problem you’re having would drive anyone nuts….good luck !!
If you’d like, your are more than welcome to give it a go as well. It’s still packed up when Matthew sent it back to me. Try it for a week or so maybe it makes a difference, maybe it won’t. Worst case scenario… the cost of postage sending it back…. If you decide to…let me know. This problem you’re having would drive anyone nuts….good luck !!
RodrigzCrzr
SILVER Star
