Thanks for that. Hose ordered.
E3 2500 Zenith Cold Start Rough Running
- Thread starter E3_UK
- Start date
not sure what is a bulkhead, not an expert in foreign languages, but from fuel pump to end of metal supply hose count 1,7m (metal tube ends at wheel well)
from fuel pump to T 10cm, from T to carbs, 20 and 30 cm respectively,
say 2,7 m and you are done
if you add a filter and an anti return valve with 2,3 m is enough
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this is fantastic first time i see that the tube for the oil mist and gases protruding from the cyl head cover is not protruding at all
Excellent, thank you. In the US it would be called the firewall.
yes, firewall !
that one i knew, thank you
...p.s. i do have problems with trunk and boot, but you know what i mean,...
Its just the camera angle making it look like it isn't protruding.this is fantastic first time i see that the tube for the oil mist and gases protruding from the cyl head cover is not protruding at all
After further investigation, the rear carb' choke isn't responding from a cold start. The front choke immediately opens partially when the engine fires then gradually opens fully after around 5 minutes. The rear carb' choke flap doesn't move however when opened manually in time with the front carb' the engine runs fine. I have removed the cover and have continuity to earth from the feed terminal to the end of the heating element, although initially I couldn't achieve continuity therefore I am still a bit suspicious that the element may have a break that I have disturbed by poking with the probes and have now temporarily re-established connection. Anyway my question is, what is the interaction between the electrical heating and water heating of the bi-metallic spring ?. Is the electrical supply cut off when the coolant achieves normal temperature, triggered by the temperature switch in the manifold and thereafter the chokes are held open solely due to the coolant temperature ?. I expect the rear choke would open eventually as coolant temperature rises but until then it will be running over rich. I'm guessing it will be difficult to source a choke cover, although there must be plenty lying around having been swapped out with Webbers ?
After further investigation, the rear carb' choke isn't responding from a cold start. The front choke immediately opens partially when the engine fires then gradually opens fully after around 5 minutes. The rear carb' choke flap doesn't move however when opened manually in time with the front carb' the engine runs fine.
Here is your problem, if it does not open at the begining, it has nothing to do with the solenoid heating element, you must find cause in lack of vacuum (unlikely), stuck elements (probably) broken triangular membrane (probable)
I have removed the cover and have continuity to earth from the feed terminal to the end of the heating element, although initially I couldn't achieve continuity therefore I am still a bit suspicious that the element may have a break that I have disturbed by poking with the probes and have now temporarily re-established connection. Anyway my question is, what is the interaction between the electrical heating and water heating of the bi-metallic spring ?.
My assumption is electric heater is not that relevant in mild climates, IMHO, the electric heater help the coolant that is principal actor
Is the electrical supply cut off when the coolant achieves normal temperature, triggered by the temperature switch in the manifold and thereafter the chokes are held open solely due to the coolant temperature ?.
Not in my setup, but I learnt that there is a relayed version which I assumes might be yours with the temp sensor present behind the front manifold cover, you should have a relay in the brake booster arm
I expect the rear choke would open eventually as coolant temperature rises but until then it will be running over rich. I'm guessing it will be difficult to source a choke cover, although there must be plenty lying around having been swapped out with Webbers ?
Yeah, plenty of those swapped ones laying around, just in the same condition as yours
IMHO you should clean, overhaul and reset those carbs, once in a 40 years time is due.
I agree regarding the rebuild, that will be a job for next winter. In the meantime, I now know that the heating element is definitely broken. I have still to check the vacuum pull down diaphragm and to verify that the rod is free to move. Regarding electrical vs coolant action on the choke, this morning before removing the cover and starting from cold the rear choke didn't move at all whereas the front was fully open in 5 minutes. If this was determined mainly by the coolant temperature then why did the rear choke not move ?. The mechanism is free. It is my assumption that the electrical element is doing the work early on and the coolant thereafter holds the choke open so I do still need the electrical element for cold start. It is not driven in the winter however in Scotland the summer temperatures are not hot, especially in the mornings therefore electrical heating is probably a necessity. I'm trying to source a replacement choke cover now, not sure how easy that will be.
So I managed to remove the pull down diaphragm. Now a quick question regarding the choke flap setting stage 1, flap fully closed. When the procedure states that the fast idle adjusting screw should be pointing to the uppermost notch on the disc, does this mean that the screw is sitting on the highest point of the cam, or on the next step down ?.
you need to make more room
Managed to remove the diaphragm. Ref. my next question above regarding first stage setting, can you explain the idle screw position on the cam more clearly ?
highest
Excellent, thank you. Perhaps if I learned Spanish I could have gained this information from your videos
i read it yes
to make more room, that you will need to install it back simply free the rod that actuates over the buterfly
Excellent, thank you. Perhaps if I learned Spanish I could have gained this information from your videos
definitely yes
, or is it definitively ?
New choke unit and pull down diaphragm fitted to the rear carb' and it is now starting perfectly. One issue however is that the choke flap sticks a bit and I have to tweak the three clamp screws to allow it to free off fully. The screws are only just nipped up from slack and as evenly tightened as possible. The face of the new choke housing can't be perfectly flat presumably.
On another note, adjusting mixture and idle speed. I have followed Steve's procedure as best i can, using just the Carbmate. I did the full adjustment initially with the air cleaner removed for easier access. Everything nicely balanced then air cleaner back on. Idle rev's were a bit high so I hooked up the carbmate again without removing the air cleaner thinking it wouldn't affect anything however the rev's dropped right off making it pointless trying to adjust the throttles. Removed the carbmate and fitted the vacuum lines back on and it was still running a little fast so I just had to tweak the idle screws without the meter. Also found it impossible to get to the front carb' adjuster so will try to add a short piece of hose to the screw head for remote adjustment with the air cleaner on. Maybe I'm missing something but I'm annoyed that I had to blindly screw up the balance without the carbmate after all the time I spent getting it spot on.
On another note, adjusting mixture and idle speed. I have followed Steve's procedure as best i can, using just the Carbmate. I did the full adjustment initially with the air cleaner removed for easier access. Everything nicely balanced then air cleaner back on. Idle rev's were a bit high so I hooked up the carbmate again without removing the air cleaner thinking it wouldn't affect anything however the rev's dropped right off making it pointless trying to adjust the throttles. Removed the carbmate and fitted the vacuum lines back on and it was still running a little fast so I just had to tweak the idle screws without the meter. Also found it impossible to get to the front carb' adjuster so will try to add a short piece of hose to the screw head for remote adjustment with the air cleaner on. Maybe I'm missing something but I'm annoyed that I had to blindly screw up the balance without the carbmate after all the time I spent getting it spot on.
Thanks, most informative videos indeed. Unfortunately I need to ask about my specific setup using the Carbmate as it's all I have. Looking at the photo below I am connecting it to the vacuum ports to the left of the vacuum units. These are connected to a T piece with the third tube normally connected to the air filter housing. So having connected the Carbmate to these two ports I adjust the mixture screws to achieve smoothest idle then adjust the butterfly screws to balance per the Carbmate with a 900rpm idle. All going well I then reinstalled the filter housing and vacuum connections and the idle speed was a little high. I then reconnect the Carbmate to lower the idle and keep the balance however with the Carbmate connected (air filter housing still on) the revs drop way down to about 300 so I can't adjust the idle unless I remove the Carbmate and reinstall the vacuum lines therefore I'm adjusting the idle speed with no check on synchronisation, not ideal. I know this has all been done to death but there must be something obvious I'm missing here.
20180511_120216 by Robin Derrick, on Flickr
20180511_120216 by Robin Derrick, on Flickr