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steam coming from radiator cap on top of motor.

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Old 11-17-12, 01:20 AM
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TX steam coming from radiator cap on top of motor.

alright so i just bought an 87 13b nonturbo. car sat for 2 weeks and wouldnt start. ive learned its the apex seals drying out from sitting. so i push started it and it fired up. leaks coolant from the waterpump and i think the rad cap on the engine (mine has two rad caps, one on the radiator) is not as tight as it should be. i topped it off with water before testdriving it. and after about 10 minutes after parking it. steam was shooting out of the engine mounted radiator cap. im completely new to rotory motors but im assuming its overheating. the add coolant light and coolant fan lights come on. what is the coolant fan light indicate?? i have a feeling my water pump empeller came off so coolant hot coolant isnt reaching the sending unit giving the dash a normal temp reading. could this be the case? remember i do have a pretty bad coolant leak from the waterpumps weap hole. rear right wheel sounds horrible, found later a brake pad between the rotor and backing plate!!! how is this caliper not blown yet?? wow so im assuming new rear rotors a right rear caliper and fresh pads all around. also car grinds going into 3rd, looks like it will need the transmission overhauled. luckily i got a buddy that knows how to recut the syncros and stuff to make it work properly again, most of the time no parts need to be replaced! AC does not work, and no air blows out the vents, where is the blower motor? i looked at the car right at dark time so i didnt have time to check for it.
Old 11-17-12, 01:23 PM
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replace the rad cap. the system wont make pressure if your cap is leaking. same if your water pump is leaking. just because its a rotary doesnt mean that the cooling system is that much different from a piston engine.
Old 11-17-12, 01:43 PM
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Change your water pump for starters . they not only leak water out but sometimes they suck air in causing problems with circulation . Get a new cap for the thermostat housing , you will never get it fixed if you don't fix what is obvious first . I'm not saying the impeller is ok but almost never do they comes off the shaft . If the rear brakes are wore out there is a good chance that the front may also need some attention as the front usually wear out twice before the rear need work . Gerald m. go to this link and download your copy of the FSM's and do some reading ,they are free . Foxed.ca - Mazda RX-7 Manuals
Old 11-17-12, 06:31 PM
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TX

so i picked it up today! im pretty excited to be messing with a rotory thats for sure. its like im starting back on square one with this thing. ok so today i ordered a waterpump, oil pan gasket, front and rear brake pads, right rear caliper, oil filter, thermostat. i forgot to get the radiator cap though. ill be waiting till the end of the month for all my stuff to get to autozone (figured parts for this car would be tough to get) ill keep you informed of my progress. first things first is fix the cooling system and change the oil. as of right now the car wont start on its own cold but easily starts if i push start it. i wonder why that is? from what i can tell the engine is spinning over at around the same as a piston engine would. is the engine supposed to spin over super fast with the starter? my car does have a flat spot at around 3-4 grand which is supposed to be the secondaries? how many injectors does this engine have?
Old 11-19-12, 05:01 PM
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I had a coolant leak up by the engine/thermostat; turned out the cap mount is made of plastic and had a hairline crack; cap was ok. I sealed mine with a plate cause they are $50 and am saving money till my engine is sound. I am also leaking pressure thru a small plug on the radiator by the upper hose; have not found a replacement part anywhere yet so I had to make a gasket for that for now. Learn where the weak spots are from me.
Old 11-19-12, 05:15 PM
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Spark plugs are very important; plugs need replacing every 5-10,000 miles; NGK or Denso plugs. Wires are more important than normal 4-strokes also. Oil changes and type of oil are critical; 3000 mile oil changes and run Castrol 20w-50 if you can. Do a compression test to see if you have enough compression. Seems like these engines have a narrow acceptable compression range. If the compression is low, something is wrong and it can get worse very quick. Rebuilds cost $500-1000 plus labor but a ruined engine will cost you $3000.
Old 11-19-12, 05:23 PM
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RX7's are a little odd and what you don't know can hurt. There are several folks on this forum that have vast knowledge. Do lots of reading and get to know Aaron Cake and Rotary Evolution. See below: https://www.rx7club.com/2nd-generati...7/#post5131155
Old 11-19-12, 05:27 PM
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Try replacing your radiator cap
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