K-RX7 101.7 FM

Wonder what a tell tail sign would be that my 7 is burning coolant ?

I noticed that i have had to add coolant last three times i drove it ,and i didn't see any coolant on the ground . It has been small amount s that i replaced , about 16 oz or less .

I just got engine coolant added after replacing heater core and thought maybe just needed to get ran through engine before it would get to a stable lvl , and my coolant in the overflow return jug is at proper lvl .

Just startd to think after the second time of adding coolant it might be losing it in the combustion chamber ,

Maybe i have the first rotary steam engine out there ?

Thnx for help ...

K-RX7 101.7 FM

Delete - I found some answers on how to tell if it is burning and it doesnt white smoke or smell sweet on the exhuast so I think it must be just a med sized air pocket that needed seetling , I ll keep watching the coolant lvls = )

Sponge Bob Square Pants

Well if you're losing coolant, there isn't too many places it can go.
It could be leaking out, but as you said, there would usually be a spot on the ground. It has happened before with really slow leaks that they are getting evaporated by a hot component (ie: exhaust manifold) but that's unlikely, especially on the rotary due to it's design.
It may be a small leak with the water jacket inside (most likely). How many miles on the engine since last rebuilt? Overheated at all?
You may want to consider taking the engine apart to inspect and refreshen it up.

Also, burning can usually be detected by a sweet smell and/or white exhaust.

K-RX7 101.7 FM

Also, burning can usually be detected by a sweet smell and/or white exhaust. [/B][/QUOTE]

Delete - I found some answers on how to tell if it is burning and it doesnt white smoke or smell sweet on the exhuast so I think it must be just a med sized air pocket that needed seetling , I ll keep watching the coolant lvls = )
Crossed in posts I'll bet ,

I really hope it was just a big bubble , cuz I bought this engine and told had just 35k on it from wrecked mazda .

I know you not supposed to believe everything you are told from people but this guy races them in Bonneville speedway and I have directions to his house , LoL

If it is a water seal , I hope i can find a good link to some really good step by step s on rebuild , Or i will just save 2k up and get a reman ...

Sponge Bob Square Pants

Yeah, hopefully it's ok.
If not, you can rebuild it yourself if you know how to operate some basic tools (socket set and a couple flat wrenches). Easiest mass produced engines in the world to rebuild.

K-RX7 101.7 FM

I have those tools , and i took the burnt engine out and put this eng in all by my self, I am getting pretty good at this engine , I was alittle leary about opening one up and switching out the rubberbands inside = )

It always looked like a the insides of a clock from the pages of my Haynes mazda book , but if it is that easy , then I might clear out the Garage and give it a whirl with the old motor first = ) I am too cautious sometimes ... At least if I do have a good engine still , I will have another good rebuild as back up .

mad_7tist

check the cap on the ast. mine went bad and so did another fd here in tampa 1 week later. the cap would not hold vac so it will not draw coolant in from the resivior. GL

K-RX7 101.7 FM

Thanx for cap info , so i took you up on it and bought the T-stat and a new pressure cap , I bought a cheap stat from napa b/c my Mazda Oem T-stat won't be in till next week and i want to get to the bottom of this overheating annoyance I have'nt started the car today b/c i want to wait the full 24 hours for my hi temp make a gasket sealant to fully cure ,plus I had alot to do at the radio station today and it's dark now ...Lmao , ---WAY--- too much info !

K-RX7 101.7 FM

Ok , Update time ... I installed the T-stat and the pressure cap yesterday and today i started the 1986 RX-7 to see if i had cooler temps and zero leaks .
well i had much cooler temps at 1/4 on the water guage , I mean i reved it and raced it but I couldn't get that thing to get to half way ... Coolness ,

so moving right along , the rez works now too sucking up reserve coolant when it needs , but heres the problem , I have coolant spray into the drivers side inside compartment near where the heater core(I just replaced) goes out ...

I wonder if i stretched the little rubber hose with all the hot coolant circulating thru the engine ? If i have to tear into that dash again would i be looking at a new Heater core ? or do theses 2inch rubber hose conectors stretch and leak ?

I know I will more than likly need to get in there to see so it matters not , just wonder going into this if any have had this problem as well ?

K-RX7 101.7 FM

found the leak , it was a bad clamp on the inlet to heater core from engine side of firewall that was allowing coolant to leak out at higher rpm s , that fixed it no longer leaves any traces of coolant on ground now and that is tight !

K-RX7 101.7 FM

found the leak , it was a bad clamp on the inlet to heater core from engine side of firewall that was allowing coolant to leak out at higher rpm s , that fixed it no longer leaves any traces of coolant on ground now and that is tight !

allforjesus06

those hoses often fail due to the location they're at, had to replace mine also. i had the same problem as you, i would let it sit in my garage, and there wouldnt be a leak. but i'd go around and drive it for awhile, and it would run out. one day i revved it up in my garage being the 16 year old i am, and bam, coolant lake on my cement. if you do your oil changes nicely and cleanly, you will preserve your hoses - because the hoses will soak up oil, and eventually burst. so be professional