1977 2F idle issue

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FJROSS

FJROSS

10 Year 15 Year
Joined
Feb 5, 2008
Threads
107
Messages
470
Location
Carlstadt New Jersey
So just a little back round. 10 years or more back, I had Jim C desmog my 77 and at that time we bypassed the vacuum advance by capping off the ported connection on both the dizzy and the carb and the engine ran fine. I recently performed a body off and had the engine rebuilt as well as sending the carb out for rebuilding. I also added a ss header with a Remflex gasket and installed block off plate with gasket on the bottom of the intake manifold. On the initial startup, we notice the vacuum cutoff solenoid was not functioning and replaced it with a single wire Nakamoto part # 21062 61010 I believe from Racer LLC. The plug didn't match so I had to solder the old connector onto the FCS.

At this point, as I read in other posts, the engine will not idle unless the choke is out and around 1000 to 1100 rpms. I removed the FCS and inspected the o-ring and added some grease to it before reinstalling and still no idle. I also retorqued the Remflex gasket since the engine heated up a bit and just tweaked them slightly. The instructions on the gasket was around 27ftlbs and maybe tighten a quarter turn on intake and exhaust bolts.

Correct me if I'm wrong, there is only two vacuum ports on the intake, one to the carb and the other to the brake booster.

1. Is it possible even if the new FCS is making a clicking noise that it is not seating and causing my issue. Is Nakomoto the only supplier of the single wire FCS from Racer LLC??
2. Should I isolate the vacuum line going to the brake booster and see if this could be the issue as far as a vacuum leak?
3. Dizzy was dropped in by engine builder at TDC and hasn't been removed since.
4. Am I missing the any other than the 2 vacuum ports of the intake manifold?

Any suggestions would be greatly appreciated.

Thanks Dave

dizzy.webp


carb 1.webp


carb 2.webp
 
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11000 RPM's there is your problem.:)

Did you check the valves and timing again? Big hemostat on brake booster hose - clamp on clamp off does it make any difference? I use a can of WD-40 with a pee tube to check for vacuum leaks - with cold engine idling, lightly and quickly spray along the intake gasket top and bottom then around all the levels in the carb gaskets - rpms kick up there is your leak.

You have fresh gas and a clean (dry) fuel filter?

So what is the flange thickness on the intalke and the header - mine was like 1/4 of an inch. Instead of half washers, I made custom stepped washers to apply equal torque to both intake and exhaust. I also used 2 Man-a-fre gasket that were softened in water. Torque was done in sequence by thirds. After fire up I re-torqued them at 100%. After several heat cycles I did them again. It has never leaked - same parts used on two different engines and mounted at least 3 times total.
 
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Take a pic of the whole engine bay. You’ve got vacuum sources on the carb ports, as well as vacuum off the manifold for the choke breaker, pcv, brake booster. Some carb insulators have a vacuum port; does yours and it’s not capped?
Are you sure the click you hear is the fuel cut solenoid?
And as said, check the timing.
 
Here we go again..........same diagnosing.......

1. Connect a vacuum gauge.
2. If your ICS is clicking with battery power and the O-Ring is intact, no damage, you are OK.
3. Connect ICS to known/tested 12v to rule out wiring.
4. Start truck, use choke to idle.
5. Verify fuel level is middle-ish of sight glass, what you're looking for is good fuel flow and not overfilling bowl.
6. Allow it to warm up a little then slowly remove choke, if it dies, restart and leave it at the lowest possible idle with choke.
7. Connect induction tachometer to verify idle speed is BELOW 950 rpms.
8. Check timing is at 7*, no vacuum lines connected to distributor. If adjustable timing light, ensure no timing advance is added via the knob adjustment on timing light.
9. If timing is at 7* under 950 RPMS, then tell us what your vacuum is at the known operating idle.
10. Using idle SPEED screw, attempt to lower idle, not the choke adjustment screw on the Primary Throttle shaft and not the Idle Mixture Screw that faces the valve cover.
11. If you cannot lower the idle at all, disconnect throttle linkage from chassis to carb then verify the butterflies on the carburetor are completely closed, this is important. You must also confirm the secondary throttle plate is closed as well, which in your case it should be.
12. If vacuum is under about 17inHg estimated, this won't cause leaks but they need to be resolved. I don't like folks driving a truck with vacuum under 20 if they can avoid it, they start to create issues.
 
FJROSS said:
Thanks,

As per the second pic, I have both the vacuum port capped on the base of the carburetor.
Click to expand...

Don't do this, but you can leave them open and it wouldn't cause your issue, they won't make the engine stick at 1100. It just causes air leaks when the throttle plate opens as they are ported vacuum. Sticking at 1100 is caused by the primary throttle shaft being bound up by something or misaligned or another major issue like a vacuum leak.
 
Thank you all for the replies,

So, I ended up speaking to Jim @ TLC who originally desmog the carb 10 or so years ago. While running and trying to idle, I have fuel dripping into the primary which should not be. I also checked around the entire intake/exhaust gasket as well as the bottom intake blank off plate with carb cleaner and couldn't find any vacuum issues. I also clamped off brake booster hose as well. Jim offered to run the carb on his test engine, so this should eliminate if it's a carb issue or vacuum issue. While packaging up the carb for shipment that went out this morning, I did notice that the primary butterfly looked to be slightly opened. Hoping this may be the issue.

Thanks,
Dave
 
Another side note, unless the intake manifold was cracked, the block off plate with a header is just wasted money. If the intake manifold was cracked, the block off plate is a bandaid and a constant tuning headache if the gasket leaks.

But I’m in the same boat as I think @mattressking; there are specific steps to diagnosing problems that no one wants to go through.
A lot of people seem to have had their engine “just rebuilt by a landcruiser guru” or just had “the best landcruiser shop in the world” restore their cruiser, but they are here asking questions instead of having the shop fix it….
 
mattressking said:
Stop guessing, when you get the carb back connect a vacuum gauge, a good carb only works if it has strong vacuum.
Click to expand...
I think you should sell posters of your earlier post with steps 1-12. We could all benefit from having that posted in our garage :D . Sell it packaged with a vacuum gauge!
 
There are 12 step programs that work for people! I see no reason not to have them for things like carbs, brakes, electrical....
I would add the zero rule - 0. Just because you bought and installed a new part doesn't mean its GOOD.
 
Update?
 
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