MDH33
Hard Core 4+
Is there a vacuum line running off the right side of the distributor? (from the diaphragm housing). If so, where is it going?
Engine diagnosis help in Denver? (FJ40)
- Thread starter Azrael
- Start date
wesintl
Moderator
That's a non usa vac advance dist
MDH33
Hard Core 4+
Not sure if the non-usa distributor has mechanical advance in addition to the vac. I'm betting that you are not getting enough advance with that line on your distributor disconnected. It should be connected to ported vacuum on the carb body.
It doesn't look like the Weber has any vacuum ports, though. I'm not sure if there's a viable workaround for that or not.
I'm also still not sure how this problem is popping up now after working fine for so long. Seems like not having a vacuum on there should have been a problem from the get go.
I'm also still not sure how this problem is popping up now after working fine for so long. Seems like not having a vacuum on there should have been a problem from the get go.
Have you tried spraying carb cleaner into the carb throat to see if that has any effect?
Most people I know who had webers on a 40 pitched them and went back to stock after they ran for a while they developed problems
Most people I know who had webers on a 40 pitched them and went back to stock after they ran for a while they developed problems
MDH33
Hard Core 4+
Look around the carb body below the level of the butterfly. I think the webers do have a ported vacuum connection somewhere.
IIRC, the Weber 32/36 is a unit that works ok (and just ok) on a 2F, though as Romer said most people eventually get to the point where they put a stock Aisan back on.
As far as stumbling is concerned, the accelerator pump (I'm assuming Webers have these like any other carb I've seen) may have gone bad for some reason. If you take off the air cleaner and look down the throat of the carb and pull on the throttle linkage, a spray of fuel should go into the carb. Not a dribble, but a stream. If that is not working for some reason, then you may have stumbling issues when you hit the gas. And like Martin said, there should be vacuum advance on the distributor (seeing as FJ40s did not come with electronically controlled timing), and a vacuum hose should be running from the distributor to a vacuum port on the carb. I can probably come over tonight for a little bit and take a look-see, though I don't really know all that much there are a few basic things I'm aware of.
As far as stumbling is concerned, the accelerator pump (I'm assuming Webers have these like any other carb I've seen) may have gone bad for some reason. If you take off the air cleaner and look down the throat of the carb and pull on the throttle linkage, a spray of fuel should go into the carb. Not a dribble, but a stream. If that is not working for some reason, then you may have stumbling issues when you hit the gas. And like Martin said, there should be vacuum advance on the distributor (seeing as FJ40s did not come with electronically controlled timing), and a vacuum hose should be running from the distributor to a vacuum port on the carb. I can probably come over tonight for a little bit and take a look-see, though I don't really know all that much there are a few basic things I'm aware of.
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You may have just hit it there. It's definitely not a mist that's coming out. I'll check that out tonight, as well as run some carb cleaner and see what happens. If it is the accelerator pump, how would I go about fixing that?
Also, I've searched that carb from every angle, and just don't see any vacuum port, let alone a free one for the dist.
rebuild kit. Usually it's a plunger inside a cylinder. The cylinder fills up with fuel when running normally, then when you hit the gas the plunger pressurizes the fuel slightly to force it into the intake just as the butterflies are opening up.
The plunger can become deteriorated, the walls of the cylinder may be dirty/have stuff that has destroyed the plunger, or the paths for the fuel to flow may be blocked. Checking the fuel filter (easy to replace)/fuel lines for cleanliness, as well as the bowl on the carb should help, but if you end up doing a rebuild make sure to clean out the fuel passages with a solvent and then blowing clean (from both sides if possible) with compressed air.
The plunger can become deteriorated, the walls of the cylinder may be dirty/have stuff that has destroyed the plunger, or the paths for the fuel to flow may be blocked. Checking the fuel filter (easy to replace)/fuel lines for cleanliness, as well as the bowl on the carb should help, but if you end up doing a rebuild make sure to clean out the fuel passages with a solvent and then blowing clean (from both sides if possible) with compressed air.
Pulled the plugs last night, and they were carbon fouled. It wasn't very bad, IMO, but I replaced them anyway. Took it out for a test and the hesitation disappeared. I was fooled once after I replaced the PCV, so I'll give it a couple more test runs to be certain it's OK. If it's good to go, I guess I just have to prevent it from running rich.
I've been playing around with the mixture screws, following Weber's tuning instructions, and I can't get it to lean out. I'm guessing I'm going to need to rejet before getting it tuned correctly. Also, I think the valve seals are starting to crack, which could be adding to those deposits.
Hopefully this gets me running somewhat reliably.
I've been playing around with the mixture screws, following Weber's tuning instructions, and I can't get it to lean out. I'm guessing I'm going to need to rejet before getting it tuned correctly. Also, I think the valve seals are starting to crack, which could be adding to those deposits.
Hopefully this gets me running somewhat reliably.
Glad you got it running
MDH33
Hard Core 4+
Round 2:
After getting it running with those plugs, it worked great for a couple weeks, but symptoms started coming back. I figured this was going to happen between running too rich and figuring out the timing. I started working on timing, but idle has been very rough,and the BB bounces around to a point that makes it hard to read. I believe part of that is that I may not be getting spark to #6.
After that, I ordered new jets according to sizes TreeRoot wrote up over on IH8MUD. Around the time I ordered them, a new problem arouse. After starting up and idling for awhile, the engine slowly fades and dies (average of 30 seconds after start). Since then, it got to the point where it just wouldn't start at all. The starter seems to be running strong, but it isn't turning over.
In the meantime, I went ahead and changed out those jets when they got in. The fuel system still seems to be working fine, and getting fuel through the carb, so I'm thinking ignition system. It's got a new distributor cap/rotor, but I don't have a clue how to test/adjust points. Can't seem to find a good write-up on that. I also threw on a new coil, because it was cheap, and I figured throwing money at it would make me feel better...
I pulled the new plugs, and they were wet fouled this time around. Cleaned those up, and reinstalled them. Need to head over to Harbor Freight and pick up a spark checker and remote starter so I can test those.
Any other thoughts/suggestions on things this time around? Can any one guide me on the points help?
Edit: Also, the battery doesn't last long when cranking it before I have to put it on the charger for a couple hours. The alternator tested good before all this started, but I'm sure when it stays on for only 30 seconds, it's not enough to put much back on the battery. Could it be that the battery, being in bad condition, is draining faster than the alt can keep up with, and now just can't push out enough juice at a time to run everything? I was going to save up for a red top, but if needed, I guess I can get something cheap until then.
After getting it running with those plugs, it worked great for a couple weeks, but symptoms started coming back. I figured this was going to happen between running too rich and figuring out the timing. I started working on timing, but idle has been very rough,and the BB bounces around to a point that makes it hard to read. I believe part of that is that I may not be getting spark to #6.
After that, I ordered new jets according to sizes TreeRoot wrote up over on IH8MUD. Around the time I ordered them, a new problem arouse. After starting up and idling for awhile, the engine slowly fades and dies (average of 30 seconds after start). Since then, it got to the point where it just wouldn't start at all. The starter seems to be running strong, but it isn't turning over.
In the meantime, I went ahead and changed out those jets when they got in. The fuel system still seems to be working fine, and getting fuel through the carb, so I'm thinking ignition system. It's got a new distributor cap/rotor, but I don't have a clue how to test/adjust points. Can't seem to find a good write-up on that. I also threw on a new coil, because it was cheap, and I figured throwing money at it would make me feel better...
I pulled the new plugs, and they were wet fouled this time around. Cleaned those up, and reinstalled them. Need to head over to Harbor Freight and pick up a spark checker and remote starter so I can test those.
Any other thoughts/suggestions on things this time around? Can any one guide me on the points help?
Edit: Also, the battery doesn't last long when cranking it before I have to put it on the charger for a couple hours. The alternator tested good before all this started, but I'm sure when it stays on for only 30 seconds, it's not enough to put much back on the battery. Could it be that the battery, being in bad condition, is draining faster than the alt can keep up with, and now just can't push out enough juice at a time to run everything? I was going to save up for a red top, but if needed, I guess I can get something cheap until then.
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MDH33
Hard Core 4+
A weak battery will certainly not help with diagnosing the problem. I'm still thinking it's your timing/advance. Did you get the Vacuum advance connected?
I was looking at another 40 recently and it made me think of this thread. They had the vacuum advance connected to the valve on the intake manifold (in front of the carb riser) rather than connecting it to a ported vacuum connector on the carb. Not sure if this would be detrimental, but it seemed to be working in their application.
Do you still have a toyota intake manifold? and if so, can you connect your vacuum advance to that instead of nothing?
(hopefully the toyota fj40 carb gurus will chime in and school us on vacuum advance
)Yeah, I've noticed a surplus around here. You and the rest are going to have to get legal name changes now that I rolled in to town.
My company is even worse. With ~20 employees, for awhile we had two Jeff's, Two Chris's, two John's, and three Kelly's. Very limited name pool...
My company is even worse. With ~20 employees, for awhile we had two Jeff's, Two Chris's, two John's, and three Kelly's. Very limited name pool...