m10 engine - engine water connection for choke

[JustMe]

Hey everyone,

 

I haven't posted in a while but will seen be updating the thread initially started where I'm trying to get an 02 back on the road, in Europe

 

Started from back-to-front, ie. from the trunk to the hood, and now looking into getting a weber water operated choke installed (after spending hours last night replacing the heater valve which wasnt a complete success).

 

I'm slightly confused as the current engine does not provide access to the engine coolant at the same place as where it seems to be when checking pictures about this point on the FAQ (cf. attached, blue arrow). 

 

Is there another entry where I could hook up the hose from the choke?

 

The one on the intake manifold is spotted :).

 

I'm not home but I can check the block references when I'm back (second pic shows the 7 digit engine number: 1667815)

 

Thanks for the feedback everyone.

 

JustMe

[JustMe]

[TobyB]

so if you take that (bolt? stud?) out, there's no hole to the water jacket?

 

What about the next boss forward from that?

 

If it's a European engine, you may have gotten a manual choke.

I would have thought it would have been drilled and plugged,

but, then, I've seen a few undrilled blocks .

 

A long time ago, but well into the fuel injected age, I rented a car

in the UK.  The very cute woman at the desk was kind of flirty-

so it was particularly embarrassing to have to go back in and have

her start it for me... when I didn't even think to look for a choke on

a car built in the mid- nineties...  

 

so you never know when the strangleur will sneak up and dump cold water over your head.

 

t

yep, he's losing it.

[JustMe]

Hey TobyB, 

 

Thanks for reverting, fun story, might be the UK accent that conquered you.

 

The picture I posted is that of another engine and I don't actually have anything at that place on the engine of the 02 (which is a 1972 2002 from California) ... seems like it isn't drilled.

 

Is a water operated choke then an option at all ?

 

Note: removed all the emission control... technology

[John76]

The "big dripper" water choke housing might be for plumbing into the intake manifold coolant hose.

 

[JustMe]

Hey John76!

 

Thanks for the info, I'll take a look into that.

 

Solution is then to tap into the hosing cooling then intake manifold.

 

Appreciate the help and will go down that route, unless anyone has any other suggestion!

[Mike Self]

Only a guess, but those US cars fitted with the manual choke, single barrel Solex  (up to partway through 1972 production) had either no drilled bosses for the water choke nipples, or they were plugged with bolts.  I suspect the former.   Early automatics with 1 barrel Solexes had automatic chokes, the only early cars that did.  All the two barrel Solexes fitted from mid-72 on (US cars) had automatic water-controlled chokes.

 

mike

[JustMe]

Mike Self,

 

Great info, thanks for sharing.

 

Even if its a 1976 BMW from California, the engine seems to be one from 1969 and falls within your date range.

 

The temperature switch on the intake manifold for emission control equipment measures the temperature of air, not water within the manifold?

 

Thanks

 

JustMe

 

Always amazed at the quality of info on the FAQ.

[Conserv]

Yes, VIN 1667815 was manufactured in August 1969. BMW Group Archives can provide a specific date. More importantly, the engine block will have been cast in the few months up to and including August 1969. Here’s how to find the block’s casting date:

 

 

This was well before any water chokes on U.S.-spec ‘02’s.

 

Regards,

 

Steve

 

 

[JustMe]

Thanks Conserv, came across the engine identification thread earlier to help understand that the block was from 1969

 

So here goes for some fun plumbing with a slightly more knowledgeable self! 

 

Cheers.

 

JustMe

[John76]

18 hours ago, JustMe said:

The temperature switch on the intake manifold for emission control equipment measures the temperature of air, not water within the manifold?

There are two temperature switches on the intake manifold.

The one on top between the #3 & #4 runner is the air temp switch (open < 59 deg. F, closed > 59 deg. F). This controls the thermo-start valve on the Solex carb.

The other switch is under the intake manifold (above the starter). This measures the coolant temperature and is closed < 150 deg. F, and open > 150 deg. When closed (grounded) it turns off the Black electro-valve and activates the distributor vacuum advance. Turns off the advance when the engine is warm and only gets retarded function.

A bit confusing, but not having vacuum advance is NOT a good thing.

 

Here's a sketch of the '76 Ca. car emissions for your viewing enjoyment!

 

 

Edited November 20, 2022 by John76
Correction

[JustMe]

@John76, thanks again for all the insights and great that you referred to both temperature switches for smog emission control, I had only noticed the more obvious one and quickly went back to see the bottom of the manifold and saw this...

[JustMe]

[JustMe]

 

...will plug it correctly now.

 

I did have a question given the little dripper style water choke and the block which doesn't actually have a water inlet above the starter:

 

- can I use the temperature switch spot at the bottom of the intake manifold as the second connection for the little dripper? I'm thinking no as it's almost directly opposite the other spot where the choke would be connected.

 

- otherwise, can I add a T shaped connector on the turquoise highlighted hose or should I use the yellow one? Given the size and access, I do prefer using the turquoise one :).

 

Thanks for the feedback!

Edited November 27, 2022 by JustMe

[John76]

The water choke needs coolant flow, so if connecting the manifold spigot (upper) to the coolant temp spigot (lower) is not a dead end (no flow), then it should work. Easy enough to check once you fill your system and attach your water pump belt.

John