Mexican Fuel Injection Question

[blue72beetle]

I'm converting my carbed bus engine to straight stock Mexican 1600i fuel injection. Yes, I did think about doing Megasquirt for awhile, but for now I just want to stick with all the stock stuff. May do Megasquirt in the future.

I've got 95% of the parts collected, and I think I've gathered almost all the info I need to put this together and get it going. One thing I can't figure out, is the engine temp sensor. It looks like a normal coolant temp sensor, and I can't figure out where it goes. I did find one picture that I think shows it screwed into the head, where the engine tin screws into it.

Does anyone have one of these, or is familiar with it? I don't have Mexican heads, just regular German ones. So I'm concerned that the sensor won't fit. This is one of the few parts I don't have in hand yet.

[66brm]

The sensor won't fit in your heads, there are heads designed with an extra boss tapped for the purpose, you could find out what thread the sensor is and drill/tap your current head around the rocker box somewhere

[gtmdriver]

My heads have a tapped boss but it's not for the sensor shown in the picture.

This is mine.



and it fits here

[Piledriver]

Its probably the same PTC resistor in a different body.
You could easily grind off the body of the later sensor, make it into a pigtail like Mario does for the GM sensors, and JBWeld it into a large crimp and install it on an intake port stud.

(The GM sensors are not same spec, but the idea is sane)

[blue72beetle]

Thanks for the help guys, and that picture really helps. Is the sensor port open to the rocker box, or is it closed off?

I'm assuming that it's used for warm up enrichment much like Megasquirt. Do you suppose I'd have any problems if I MacGuyvered something together? I've got a friend that's very good at welding aluminum and could probably put a boss right there on the head.

[profab]

I think Blue72beetle is right, i think it's closed off from the looks of it. Putting a boss on the head will work.

[Clonebug]

You could build a bracket and hang it underneath in the warm air flow around the thermostat or get it up close and personal with a fin in there.
Piledriver has a sensor positioned that way and it works fine for him.

More than likely it is for warmup only and just needs to get to a warmer temp fairly quick like 150-180 degrees to be effective.

[Bruce2]

Thanks for the help guys, and that picture really helps. Is the sensor port open to the rocker box, or is it closed off?

The hole in the middle is through to the inside of the rocker area. Thus, the sensor gets oil splashed on it.

In order to weld something on, you will have to remove the head. Once you do that, buy a new head with the threaded hole already. Heads are CHEAP!