Help Carbs wont pick up fuel when cold

[lyons]

Car is 3.8 E and runs ok when hot, however starting from cold it is painful.as it takes forever to draw fuel up into carbs. Usually have to resort to "Quick Start" as an answer. Ignition checked and is spot on

No obvious air leaks around spindle and butterflies fully close. Carbs have been rebuild but not all parts have been replaced, the exception being the diaphram in the base. If this is brittle (not on inspection and not torn) would this account for poor fueling draw up on start.

Any other ideas out there apart from a full rebuild by Burlen/ SUcarbs.

Thanks for all replies.

[Heuer]

The SU's do not 'draw' fuel, it is pumped under pressure. First thing would be to check all fuel filters - tank sump filter, in line filter and SU filters. Try removing the in line filter bowl and turn the ignition on to see what kind of flow you are getting. SU's need at least 2.5psi.

[christopher storey]

David : a small correction if I may. SUs need not more than 2.5 psi : an awful lot of the idling problems people suffer are caused by excessive fuel pressure , admittedly more commonly where after market pumps of the continuous flow type e.g. Facet have been fitted . Your advice about filters sounds spot on to me, although it could also be that the rich mixture linkage is not in fact lowering the jets . Failing diaphragms do not usually produce this problem, and more commonly result in leaks from the base of the carb

[lyons]

David /Chris - the fuel system is all new eg pump , in-line filter and float bowl. Have even checked the small filters in the carbs.

Disconnected the fuel line at the float bowl and presure is excellent.

Any other thoughts and ideas why she is difficult to start or are all E types like this when not used on regular every day basis.

[kingzetts]

I certainly find that my 3.8 takes a while to fire up after standing for a while. After standing for a few days, it usually deigns to run on about the 5th try, if it has been stood for say a month it can take 9 or 10 tries before it finally runs consistently - but it always starts eventually.

Once started and stopped again it will usually start first turn for a day or two.

I've never had to use "quick start" or anything else, though. I think most owners find the 6-cylinder cars can take a few goes to start from cold.

Having the ignition spot-on helps as does ensuring the cold start mechanism works (as Christopher mentions).

Cheers

[john wyatt]

best to avoid using easy start too much, are all your jets dropping fully when you operate choke?, my car takes a couple of turns before it runs if it has not been out for a few weeks, if you dont have it already would also install electronic ignition, it definitely helps, one thing I really dislike about SU's is not being able to give them a "couple of pumps" to help things along!