[Johnbear]

I'm helping my friend tune his stock 85 civic HR and i turn on the heater motor and it stalls the engine. There is alot of jackass wiring so i have no idea where to start. There is also a problem with the engine dieing at a stop sometimes(hot or cold) but thats going to take more checking up on before i can ask a question.
I know there are carb honda forums but alot of you guys play around with old import motors so i thought i can shoot here first.

 

[Billgear]

Might want to check the vacuum lines, could be a major vacuum leak. The 85' had a complete mess of vacuum hoses. There should be a vacuum line diagram under the hood some where.

 

[manley]

I agree on the vacuum lines..check them all. Remove the vacuum ball and inspect it for holes and cracks. I know someone that had a problem like this and it was due to a hole in the vacuum ball.

 

[Huskinhano]

I didn't think of the vacuum lines but that's a good call. I'd also suggest checking related wiring to the heater motor. The motor uses a fair amount of power. With it on, it may cause enough of a voltage drop to foul up the engine, especially of the wiring is FUBAR as you said.

I'm not familiar with Hondas but even if it does have a carb, it still may have a CPU to ajust fuel mixture. The voltage drop with the fan running, may give it problems.

But check those vacuum lines, check one thing at a time!

 

[Lightning]

If it has A/C look to see if It has an idle speed solenoid, if so verify that it works. Its designed to bump up the idle when the added load of the compressor is applied to the motor. Many cars use the A/C compressor in the heat mode.

 

[amartin725]

Good luck! The cars I've owned from that era have had computer-controlled carburetors (no user adjustments) and thousands of miles of vacuum hoses. Added to that, hodge-podge wiring can really give you a headache.

Al