thermal time switch

Are you talking about this switch?

http://www.ricambiamerica.com/product_info.php?products_id=194393

 

Where are you getting that part number?

My notes show that your model uses the earlier 113980 (Bosch 0280130220), not the later 118790 (Bosch 0280130219)? They are not the same...

 

That would be this one then.

http://www.ricambiamerica.com/advanced_search_result.php?keywords=113980&x=6&y=8

 

Replaced mine, same year car, about 5 years ago and everyone had them then...meaning I chose by price. Bought from TRutlands P/n 113980 incl s/h was $99.36. Installation by my mechanic was about an hour...would have taken me all day as it's under the plenum as the wrench only gains about 1/10 turn per attempt.

 

That particular thermostatic switch located behind the thermostat appears both in the 1983 Mondial Workshop manual and in the 1980 Ferrari North America's Bosch CIS training manual. But while the part is included on NA car diagrams, it isn't included on Euro car diagrams (OM 195-80). Which may explain why it doesn't appear on Ricambi's ¿Euro? parts diagrams and why you are encountering difficulty finding it. The manual refers to it as mechanically the same as the thermal switch under the expansion tank but having different temperature specs, which are:

closes 12°C to 18°C (54°F to 64°F)
opens 22°C to 28°C (72°F to 82°F)
wrench flat is "25/15"

 

Incidentally, that circuit only gets voltage in those few seconds when the key is turned to engage the starter.

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http://www.FerrariDiagrams.com

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Your description seems a little odd. I believe that item 106 on the 1980 US 308i-2V OM schematic is shown in the yellow circle in this jpeg (as Paul described -- near the thermostat, not "next to the thermal switch") -- is this the thermal switch that you are looking for or is it located elsewhere on the engine?
Image Unavailable, Please Login

 

115652

Go here:

http://www.ferraridatabase.com/The_Downloads/Manuals_Parts.htm

and download the Mondial8 US (1981-1982) Spare Parts Catalogue (it's item 51 on TAV 20) -- with regard to the engine components, it will be identical to your 1980 US 308i-2V.

Did you physically break your old one, or did it have an internal electrical fault (like always staying closed or always staying open)?

 

which where the symptoms ?
failure functions ?

 

So is the Bosch 02801130219 the correct P/N for n 84 QV? This is the switch located at the bottom of the expansion tank not the oil thermoswitch in the block I'm referring to.

 

Definitely not -- the switch in the coolant tank is a "thermal switch" -- not a "thermal-time switch".

 

Thanks Steve....So do you know the Bosch P/N for the "thermal switch" in the expansion tank? Is this the switch that controls the CSI as far as warm start is concerned?

Regarding the "thermal time switch" is the correct version #118790 for a 84QV?

Cheers

 

This thread was started a 1980 car and has moved to a 1984...the circuits are different. I won't use the word hijack but a new thread still might be in order to reduce the confusion. Incidentally, the 1984 expansion tank thermal switch is used by the lamda circuit and not directly used by the CSI.

Mcaputo - did your mechanic solve your cold start issue by temporarily bypassing the switch near the water pump, thus enabling the CSI circuit? Since cars without that circuit are sold to the Scandinavian countries and start fine, I've always been a bit surprised by it's need in Canada. Course we don't see the Swedish complaint file.

 

Sorry for for hijacking the thread. I'll start a new one for lambda circuits since there is little to be found specific to that system that I could find through the search function

 

Looking morely closely (OM 195-80) Euro cars DO have CSI but it's full time, i.e. it doesn't have the one or two thermal switches to shut down the circuit of warm engines which was added to NA cars (or more precisely added to catalytic cars). Understanding the 'why' comes very slowly for me but since F provided more venting cool the engine compartment of catalytic cars perhaps the thermal switches give greater life to the therm-time switch. Would still like to know if your car was tried without that warm cutoff switch in the circuit which disables the injector.

 

Could be that the US emissions restrictions didn't allow a "fart" of hydrocarbons at warm restart, so the inclusion of that extra thermal switch on the US version was more of a kluge to get by than something desirable for engine operation. Have you tried just shorting that switch always closed on your (US?) 308i Paul to see if warm restart is altered, or is yours a euro?

 

I can't see my 'waterpump' thermal switch much less acces it. I'm of the school which doesn't touch things which aren't broken. Until Birdman brought attention to the cold start circuit by posting his 'hate the CSI' diatribe, I didn't fully know what my expansion thermal switch did and totally misunderstood the dash cold engine light. Basically I'm trying to understand design differences through the experience of others.

My present quandry is...as the engine warms up, both the air diverter and fast idle electrovalves are disabled, but at a different temperature than the CSI is disabled. Yet Euro CSIs are never disabled. One difference between them is inclusion of the cat. Ongoing...

 

"To aid cold starting the fuel accumulator delays the build up to full working pressure on the control plunger in the MCU (mixture control unit). When the engine is switched off during or after a run, the accumulator maintains the working pressure for a limited period to assist hot starting"

 

Sounds contradictory without context. Where is that quote found?

I thought the WUR is the device which delays pressure build until full warmup and accumulator maintains pressure, however little, to prevent fuel drainback from the distributor which on my car then requires about 8-10 seconds to refill after a few days of non-use. My MB with the same Bosch injection system (wur, accumulator, dist, etc) works that same way also, taking 8-10 seconds for fuel to fill the injection system after a few days of non-use.