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Discussion Starter · #1 ·
Hi guys,

So all was well on the western front and the engine was installed, fired up and ran smoothly. this was without coolant, as i was missing my heater hoses. I finally got the hoses in and installed them, but had to lift the carbs off the manifold to get the pipes in the correct location. It didn't seem like a big job, and little could have been screwed up upon re-assembly..... or so i thought. Now the car fires up after cranking for a bit and just dies. i can replicate the results non stop with it just firing and dieing. So i retraced my work, thinking i might have a air leak at the base gasket. I made a new one just in case, and installed it. Still the same. My thought behind the air leak is that if i restrict the center butterfly with my hand (almost completely covering it) the car will run. now that must be a pretty big air leak to make that big a difference. The odd part is that if i hold the butterfly down barely open the car will run where most cars will run with the throttle bodies open, so i'm now thinking my linkage my be stuck slightly open for the carbs??? I thought of this after i left the shop as i saw the cruise control chain kind of looser than before. any other ideas? I checked for popped diaphragms and loose hoses, but all is well on that side. I tried unplugging smog components, made sure my pump is pumping, fuel gets in the carb by the needle no problem, i have spark on all plugs. if i throttle the car i can keep it running but it is very rough. it only runs decent when i keep my hand over the air inlet.



on a side note the Leatherique kit is being applied to every piece and it definitely softened the leather nicely. truly amazing. the re-dye will happen this weekend I hope. Also the hydroboost is just about done. I'm waiting on some fittings and have to make a mount for the electric hydraulic pump. I know its blasphemy to modify this great car, but safety
needs to be #1 as i'll be pulling my 57 Chris Craft Capri behind this beauty
 

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Did you reconnect the weakener and anti-diesel solenoids?

(It sounds like a disconnected anti-diesel solenoid, except that I'm not sure your car has one.)

Jeff.
 

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Discussion Starter · #3 ·
yeah, eaverything is connected under the hood. I'm assuming the solenoids work as they did last week, but i'm not not 100% sure. this model has a ton of smog stuff compared to other years.
 

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Airproblem?

Sounds like an airproblem. Is the airsensor good and connected? :idea:






:arrow:
 

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Discussion Starter · #5 ·
which one is the air sensor? all wiring in the engine bay is connected. i double checked every single wiring connection, just in case, but nothing is loose. Truthfully i dont know much about the wiring in the engine bay, aside from the components that make the car run. all the smog stuff is greek to me. i dont quite understand how the sensor affect the car, or better yet through which component they affect it, as the carbs are mechanical and ignition seems fairly separated,
 

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Andrei,

What year is your car? I've gone back and reviewed the posts and I can't seem to find the year and chassis number. Both of these would be very helpful to know.

I don't believe your car (or any of the carburetted ones) have an air sensor, but I'm not absolutely certain.

I also don't know if you might have removed and switched the anti-run-on (AKA anti-dieseling) and weakener solenoids. They work in opposite ways (the anti-dieseling solenoid is closed when energized, open when not and the weakener solenoid is open when energized and closed when not). If you put the weakener solenoid on in place of the anti-dieseling solenoid you are immediately creating a vacuum on starting the engine that's designed to starve the carbs of fuel.

These are all conjectures, but perhaps something rings a bell.
 

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Discussion Starter · #7 ·
my car is a 1976 with the dual egr on the left side of the engine chassis # LRE 23822. The cool part about the reassembly of the manifold is that the person who took it appart only unplugged the sensors but left everything else assembled. so all i had to do is mount the manifold and connect plugs. The engine ran great with nothing but the carbs and ignition attached (outside of the engine bay when tested). Now i can unplug every sensor and it still runs poorly, which leads me to think it might be more mechanical that electrical.
 

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Airproblem?

"It runs decent when i put my hand over the airinlet"....
so it must be an air problem (resulting bad gas-airmixture). :(




:arrow:
 

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Discussion Starter · #9 ·
i'm beginnig to think its something related to the egr, after reading the emissions section of the manual. possibly some hoses swapped or wires at the solenoids. Egr is the only thing that could allow that much air in the engine. will find out in about 2 hrs
 

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I think Brian might have been on the right track with mixing up the anti-dieseling and weakener soleniods.

The two hoses E and F in the attached picture place a vacuum on the float chambers, reducing the fuel delivered. Pinch both of them closed and see if it starts to run well.



Jeff.
 

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Jeff,

Check the key for that diagram again. Hoses E & F appear to be the overflow hoses. If one of the needles gets stuck and too much fuel makes it into the carb this allows it to be dumped through the funnel-like contraption numbered 5 in the diagram.

Hoses B & C are the two connected to the anti-dieseling and weakener solenoids (and I can't remember which is which without my key) and that's where the vacuum on the float chambers comes from [or, I should say, is allowed to pass through or not].
 

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Brian,

B is the weakener line, and provides a partial vacuum (from the throttle butterflies) to weaken the mixture slightly.

C is the anti-run-on line, and provides full vacumm (from the inlet manifold) to really weaken the mixture (and kill any dieseling).

E and F are what transmit either the partial or full vacuum to the float chambers, which is what actually does the weakening. But yes, they also serve as vapor relief lines under hot-soak conditions and fuel overflow lines if the needle valves stick.

Jeff.
 

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Discussion Starter · #14 ·
well my gents,

it is running perfectly. i went through the wiring and hoses, and all was just fine except for the power input feeding into the secondary harness, which i had connected to both the leads of the choke solenoid. and the ground side i had connected to the power input on the secondary harness. in any case, the car started right up and it runs fantastic. aside from a little ticking from the brake pumps the engine is smooth as new.

thanks again for all your efforts.

i will be finishing the brake work by this week and the leather re-dye by this weekend hopefully i can be driving by the next 2 weeks.
 
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