Removing internal thermostat without dropping engine

[JT]

I have my ’81 3.0 lowered as far as it will go and have a simple/dumb question. Is the thermostat on the left of the oil pressure switch or is it under the gray cover over the cooler?

Thanks,

JT

[efhughes3]

It is under the aluminum cover near the pressure switch.

[tevake]

Hey J T Do you know about" PET Porsche Parts" It has a complete parts break down and assembly drawings, and parts #s. Very helpful to locate parts and understand how they go together.
You can Google it and down load for your year/ model, It takes a few minutes to down load.
I just got turned on to this a few months ago and love it.

Cheers Richard

[JT]

Richard,

Yeah I've looked at PET, but that really doesn't make it clear for me. My buddy who does a lot of 911 engine work says the thermostat is not under the aluminum cover, but Ed says it is. Another thread implies it is also. I can see something that looks like the thermostat and has 2 10mm nuts, just as described on the thermostat. I've removed the nuts, but cannot seem to pry up whatever the nuts held down. I'm hoping that's the thermostat as I cannot seem to get the aluminum cover off. A new thermostat should arrive Monday, so I guess I could wait until then, but I have a track event on the 26th and want to be ready. There's never enough time.

JT

[boyt911sc]

JT,

The engine thermostat could easily be removed by prying it up after you removed the two (2) securing nuts. The O-ring gives a very tight fit and resistance to slide easily. After you cleared the 2 studs, rotate or wiggle it out.




Tony

[JT]

Ed, Richard & Tony,

I got the sucker out, but had to remove a lot of the smog hoses and valves. Hopefully I can get them reconnected, although I would love to take them off. Since its a track car and a '74 it's CA smog exempt. However, i'm afraid to just take everything off, it might not run.

Thanks again for your help.

JT

[efhughes3]

Congrats. Are you going to replace the breather gasket while there?

[JT]

Since I'm pressed for time and really don't know what the breather gasket is, I don't think so.

[efhughes3]

It's under the oval cover next to t-stat. That and the pressure switch are part of what should be replaced if you're at this point of access.

[JT]

Oh boy, that's what I initially thoght was the t-stat, but couldn't remove it. What's the secret and why does the gasket need replacing? I didn't order one and really don't have time to wait for one.

[efhughes3]

That's the breather and one of the three leak points in that vicinity.

[JT]

I had a slight interruption to attend my aunt’s funeral in Texas, but now I’m back with a little more time. I’m still looking for options to remove some of the smog hoses since this is a track car. The back bending begins anew on Saturday.

[boyt911sc]

Originally Posted by JT

I had a slight interruption to attend my aunt’s funeral in Texas, but now I’m back with a little more time. I’m still looking for options to remove some of the smog hoses since this is a track car. The back bending begins anew on Saturday.

JT,

If you want it done correctly and quicker, consider an engine drop. The backbreaking work could be eliminated unless you don't care having a sore back and you're young. Add up all the time and effort you had spent with the engine installed doing what you did. With the engine on the floor or dolly, it would take minutes to accomplish the same work you have done earlier. Just my two-cents.

Tony

[LakeCleElum]

Originally Posted by john walker's workshop

be sure to disconnect the shift coupler. lower it until the fan housing just clears the rear cross-member. that's about the end of the safe/won't bend anything range. that's where it needs to be if you remove the engine and leave the trans in place, if you were to do that.

OR, you can just pay JW a reasonalble fee to do it and it will be done right!

[JT]

I’ve got the thermostat installed and am currently reconnecting all that damn smog stuff. Unfortunately, I’ve come upon a blue plastic electrical connection with 2 prongs that sits behind (toward the front) the sensor plate in the throttle housing. Any idea what it’s for? I can’t seem to find the connection wire. Be advised that this is a ’81 3.0 in a ’74. Here’s a picture. BTW, I did lower the engine quite bit and I did disconnect the shift coupler – thanks.

[john walker's workshop]

the green connector goes there. it's hanging down behind somewhere. get a mirror. sensor plate fuel pump relay cut-off switch. so the pump doesn't run with the key on, engine off. grounds the 86 terminal on the FP relay until the sensor plate raises.

[JT]

Oh no, I can't find the green connector and don't even remember disconnecting it - old age and too long ago. Where does the green connector come from? Maybe I can trace it from its source.

Bob S., John Walker is a little far from me, but I'm about ready to get some physical help. This car was originally from Seattle, but since '79 it's lived with me in the SF Bay Area.

[chrismorse]

Shortly after installing an 85 front fender cooler,i was cruising down the road, well warmed up and everything behind me was blue fog.

Somefool had overtightened the two tiny 6 mm bolts securing the thermostat to the mag block and the car dumped 12 quarts of oil in 2 seconds.

If you drop the engine, you can install helicoils in the block for this precious part and avoid tragedy.

hth,
chris

[JT]

Finally got everything back together. I even found that green connector (Thanks JW). Tested it out and loved it when the temp hit 180 and then dropped a bit - that new thermostat opened and no leaks!

I will add one more caveat to all the above great comments: Before lowering the motor, disconnect the wire that goes from the engine fuse box to the sending unit on the driver’s side rear corner of the motor.

Thanks again for a great thread and information.

JT

[CaptainCalf]

JT, you got a pic of the correct o-ring for that thermostat? I've got o-rings running outta my ears with the gasket kits and want to make sure I get the right one on it so there are no leaks.

Thanks,
RC