Help: Overheating Honda Civic

[Daves]

My Honda Civic has at least three engine problems, and I would like to know whether they are related. Any sharing of knowledge would be greatly appreciated. Here are the facts:

1. Ever since replacing the head gasket (2 years ago), my 1991 1.5 liter Honda Civic has been consuming oil. The local machine shop said they did a 3 angle valve job, milled the head for flatness tolerance, checked for cracks, and replaced 5 intake valves they claimed were broken. The results were 1 quart of oil burned per 1000 miles.

2. Since 4 months ago, my Civic has been running hot but only when driving 60 mph or faster for over 15 minutes. I have been compensating by turning the heater on high when driving on the highway.

3. Today my car overheated very quickly on a 10 minute trip, and when I turned the interior heater on, only cool air was available.

My initial hypothesis was that the burnt oil had clogged my catalytic converter, so the increased backpressure was causing the car to overheat when driving at higher speeds.

This new turn of events puzzles me, though. What would cause my heater to blow cold air?

[Daves]

My Honda Civic has at least three engine problems, and I would like to know whether they are related. Any sharing of knowledge would be greatly appreciated. Here are the facts:

1. Ever since replacing the head gasket (2 years ago), my 1991 1.5 liter Honda Civic has been consuming oil. The local machine shop said they did a 3 angle valve job, milled the head for flatness tolerance, checked for cracks, and replaced 5 intake valves they claimed were broken. The results were 1 quart of oil burned per 1000 miles.

2. Since 4 months ago, my Civic has been running hot but only when driving 60 mph or faster for over 15 minutes. I have been compensating by turning the heater on high when driving on the highway.

3. Today my car overheated very quickly on a 10 minute trip, and when I turned the interior heater on, only cool air was available.

My initial hypothesis was that the burnt oil had clogged my catalytic converter, so the increased backpressure was causing the car to overheat when driving at higher speeds.

This new turn of events puzzles me, though. What would cause my heater to blow cold air?

[BryanH]

Sorry to hear you are still having dramas Dave.
Hondas use low tension piston rings, If you recon the cyl head the closed throttle vacuum is improved enough to suck oil past the by now relatively worn rings. In my 6 years running Frankston Honda I saw the same situation virtually every time somebody tried it. You have to fit new rings when reconning the head.

Cold heater means no flow / no coolant left in system!!!
Getting hot over 60mph might be;
partially blocked radiator,
retarded ign timing, or locked at base timing
(ECU in limp home mode)
I never did buy the dead cat story.
water pump impellor badly corroded

[Daves]

I let the engine cool overnight, and this morning I noticed a coolant leak somewhere near the bottom of the radiator. I'll take it to a shop in the morning.

Thanks, Halfast.

[Daves]

The problem was a leak in the radiator. The shop replaced it with an all-metal (brass/copper) CSF heavy duty radiator, and now it is running cooler than ever. Apparently the previous problem of overheating on the highway was also the radiator's fault.