Overheating on the highway. 76, 2.0 Options

[SVG223]

My 914 overheats on the highway. I had concerns about the air flap, but I think the thermostat has broken and it stays in the open position. I thought something might be clogging the fan but it looks clear. I wonder about the heater air hose that goes over the motor. It could be blocking some air possibly. I may try to tie it out of the way. After exiting the highway and stopping at a stopsign the idle was extremely low, I was surprised it was still running. I turned the engine off for a while and it ran better after it cooled down. Any ideas would be appreciated.

[SVG223]

I think the ignition timing has been retarded by a bunch. I just turned the distributor counter-clockwise enough to increase the idle by 1000rpm and it ran better, so far no overheating but it's not summer yet. I need to get a timing light. I tried to get it to ping but it didn't so I need the light. It is running well so far.

[Superhawk996]

tried to get it to ping but it didn't so I need the light.

You are playing with fire.

Detonation kills engines so fast you would hardly believe it. The ability to hear detonation on an an air cooled engine is impaired by the valve clatter and fan noise.

Get a timing light on it. Stop guessing

[SVG223]

tried to get it to ping but it didn't so I need the light.

You are playing with fire.

Detonation kills engines so fast you would hardly believe it. The ability to hear detonation on an an air cooled engine is impaired by the valve clatter and fan noise.

Get a timing light on it. Stop guessing

Thanks, will do that. I didn't expect the timing to be off, purchasing it from a dealer that had done a tune-up on it. I had my doubts about it because of the vacuum hoses being misrouted. The engine runs much better now and doesn't overheat so far. That overheating was keeping me from driving it. I didn't know ignition timing had that much effect on engine temperature.

[VaccaRabite]

tried to get it to ping but it didn't so I need the light.

Get a timing light on it. Stop guessing

The engine runs much better now and doesn't overheat so far. That overheating was keeping me from driving it. I didn't know ignition timing had that much effect on engine temperature.

Too much or too little advance timing will raise temps.
Yes, put a light on it. Under no load it will be hard to make ping. It will certainly ping as soon as you put load on it once the engine is over-advanced.

Remove the crap from the engine that you are not using.
If you don't use the smog pump - pull it off the engine. Cap the ports. Those go directly into your combustion chambers. Don't trust duct tape! IIRC, an M8 nut cap works fine on the port.

And, yeah, get an inspection camera / borescope and look in your tins for debris especially your oil cooler. I'm sure its caked over with grime.

Zach

[SVG223]

tried to get it to ping but it didn't so I need the light.

Get a timing light on it. Stop guessing

The engine runs much better now and doesn't overheat so far. That overheating was keeping me from driving it. I didn't know ignition timing had that much effect on engine temperature.

Too much or too little advance timing will raise temps.
Yes, put a light on it. Under no load it will be hard to make ping. It will certainly ping as soon as you put load on it once the engine is over-advanced.

Remove the crap from the engine that you are not using.
If you don't use the smog pump - pull it off the engine. Cap the ports. Those go directly into your combustion chambers. Don't trust duct tape! IIRC, an M8 nut cap works fine on the port.

And, yeah, get an inspection camera / borescope and look in your tins for debris especially your oil cooler. I'm sure its caked over with grime.

Zach

I hear no pinging under load I may have guessed correctly, but the light will come in tomorrow so I can check. I pulled all of the smog crap off and getting some vacuum
caps tomorrow. I got a borescope camera and almost everything was covered with grease. I pumped a gallon of diesel fuel through the holes in the sheet metal, but I didn't get it all out.

[VaccaRabite]

I hear no pinging under load I may have guessed correctly, but the light will come in tomorrow so I can check. I pulled all of the smog crap off and getting some vacuum
caps tomorrow. I got a borescope camera and almost everything was covered with grease. I pumped a gallon of diesel fuel through the holes in the sheet metal, but I didn't get it all out.

Did you check and clean the oil cooler? Or is that what you were talking about?

Zach

[SVG223]

I hear no pinging under load I may have guessed correctly, but the light will come in tomorrow so I can check. I pulled all of the smog crap off and getting some vacuum
caps tomorrow. I got a borescope camera and almost everything was covered with grease. I pumped a gallon of diesel fuel through the holes in the sheet metal, but I didn't get it all out.

Did you check and clean the oil cooler? Or is that what you were talking about?

Zach

Yes the cylinder fins and the oil cooler. I had to have help with the cooling flaps to get them in the right position to flush the oil cooler with diesel. I suppose the engine would have to come out to do a thorough clean. I'm still hoping that the new ignition timing will allow me to drive it this summer.