Author Topic: TCS cold starting help.  (Read 1812 times)

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Offline ottocycle

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TCS cold starting help.
« on: Sunday,February 16, 2014, 10:10:51 AM »
Hello all,

I have not posted in a while and thought I would solicit some advice before I started to diagnose the problem, in case this was a common occurrence. My car is a pig to start when cold. I have rebuilt a set of Strombergs on my 1974 TCS and I cannot give the car enough choke to start it when cold. I realize that a lot of carb problems can be traced to ignition issues and I will re check the ignition system when I get dug into the project but I thought I would throw it out here for general discussion. Once started (I have to spray raw gasoline into the carbs to enrichen the A/F mix), she warms up and drives just fine but I should not have to do this. I rebuilt the carbs with new gaskets and diaphragms and I am wondering if I might have made a mistake when I assembled the choke discs. The carbs were gummed up when I got the car and I have no "before baseline" to go off.
Has anyone had cold starting issues with these motors and how have you dealt with it?

BTW. This problem existed before we went through this cold spell on the east coast.

Thanks,

Dermot.

Offline Bainford

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Re: TCS cold starting help.
« Reply #1 on: Monday,February 17, 2014, 01:11:07 PM »
It may be of little help, but my TCS starts willingly when cold and I never use the choke. In fact, during some carb work last summer I disconnected the choke cable and never re-attached it. Even during below freezing conditions starting is not a problem if the engine has been run in the last week or so. I guess what I'm trying to say is that these engines will cold start easily if all is well.

Just thinking out loud here; It sounds like the fuel pump needs to refill the float bowls during the cold start. Check the plug on the  bottom of the float bowls carefully to ensure they are not leaking.

If no leaks, then I think I would inspect the fuel pump. It may not be performing up to requirements and may need a rebuild. Rebuild kits are readily available and inexpensive. I got mine a Dave Bean.

Check the fuel filter and all up-stream (between pump and tanks) fuel line joints while you're at it. It may be that the pump, filter and fuel line joints are marginally suffucient for keeping a warm engine running, but are too heavily taxed to get a cold engine started. I mention specifically up stream line joints as these can be tricky to detect a leak since when the engine is running they will be under negative pressure and can draw air in through the joint, reducing pump efficiency.

Just a few thoughts. Good luck.
The Twin Cam plays the symphony whilst my right foot conducts the orchestra. At 3800 rpm the Mad Pipe Organ joins in.

Trevor

Offline EuropaTC

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Re: TCS cold starting help.
« Reply #2 on: Monday,February 17, 2014, 11:54:32 PM »
It's a very long time since I had a car with Stromberg or SU carbs, but I'll try to contribute a few ideas;

The obvious one - is the cable operating correctly or is there any slack which means you don't get full choke ?

A pure guess, but my second thoughts always go to "what's adjustable ?"  (followed closely by "what have I messed with ?"  ;)  )  So are the jet heights fixed on your carbs ? I know early versions you could set the height which meant a richer or leaner mixture from tick-over which may possibly affect starting ? The other thing is float height, that's critical with Webers but again I don't know how important it is with Strombergs but it's something I would check.

I've also used the aerosol sprays into the air filter to get something running but it's only been when the car has been standing for a while and the petrol has gone off.  Would yours start it you pumped the accelerator while turning it over, like you can do with Webers ? I realize SU/Strombergs don't have a pumped squirt of fuel into the inlet, but maybe it would lift the needle enough to enrichen the mixture ? 

Finally, as Trevor says, the fuel pump has little valves in it which might be clogged up based upon your findings with the carbs themselves. If it's an original then it is a very easy overhaul and gets rid of another potential problem.

Brian