"boil over" inti res. tank
08-17-2002, 07:31 PM
#1
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Join Date: Jul 2002
Posts: 58
'86 GXL Auto. stock
I've been working on this car for some time. I bought it not running and have had to fix a few things. I've had several 1st gens but this is my only 2nd gen.
All coolant hoses have either been replaced or checked thoroughly and hose clamps replaced. The thermostat is new from a parts store(not mazda) and the fan clutch was replaced 3 times with used ones until I found a good one.
The car runs/starts fine and the temp stays around 1/3.....for a while
once the car reaches norm. temp. it slowly starts to "boil" or "blow-out" air and coolant into the res. untill it eventually overflows....then the temp. starts to climb more and more. If I use the A/C it happens faster.
I don't see steam in the exaust (I have a modified 12a which has done this) and the coolant does get sucked back into the system while it's cooling (after turning it off)
Initially I was using 50/50 Ethtlene glycol/water but added a little more ethylene glocol (probably 60/40 now) this didn't help.
What should I try next? (Really I just want to learn /fix what's wrong and then sell the car)
I've been working on this car for some time. I bought it not running and have had to fix a few things. I've had several 1st gens but this is my only 2nd gen.
All coolant hoses have either been replaced or checked thoroughly and hose clamps replaced. The thermostat is new from a parts store(not mazda) and the fan clutch was replaced 3 times with used ones until I found a good one.
The car runs/starts fine and the temp stays around 1/3.....for a while
once the car reaches norm. temp. it slowly starts to "boil" or "blow-out" air and coolant into the res. untill it eventually overflows....then the temp. starts to climb more and more. If I use the A/C it happens faster.
I don't see steam in the exaust (I have a modified 12a which has done this) and the coolant does get sucked back into the system while it's cooling (after turning it off)
Initially I was using 50/50 Ethtlene glycol/water but added a little more ethylene glocol (probably 60/40 now) this didn't help.
What should I try next? (Really I just want to learn /fix what's wrong and then sell the car)
08-18-2002, 12:12 AM
#2
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Join Date: Jul 2001
Location: NJ
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unfortunately it sounds like you have a broken coolant seal...... and its burning off the coolant. you can get a tester to see if there is exhaust in the coolant. i would check that first so you don't waste anytime. i hope it's not the coolant seals 
08-18-2002, 07:24 PM
#5
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would it have anything to do with the radiator cap being located in the original position above the thermostat/ not on the radiator...
..or... that the generic thermostat doesn't have the jiggle pin that the mazda one has?
..or... that the generic thermostat doesn't have the jiggle pin that the mazda one has?
08-18-2002, 08:31 PM
#7
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i'm not refering to the cap but rather the thermostst itself--the mazda one has a jiggle pin and the generic one doesn't.
also for '86-'87 the is a service bullitin 07/87 about relocating the rad cap and source for the overflow---these mods hanen't been done to my '86 but...are ther truly needed?
also for '86-'87 the is a service bullitin 07/87 about relocating the rad cap and source for the overflow---these mods hanen't been done to my '86 but...are ther truly needed?
08-18-2002, 10:20 PM
#9
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Originally Posted by fstedy' date='Aug 18 2002, 06:31 PM
i'm not refering to the cap but rather the thermostst itself--the mazda one has a jiggle pin and the generic one doesn't.
also for '86-'87 the is a service bullitin 07/87 about relocating the rad cap and source for the overflow---these mods hanen't been done to my '86 but...are ther truly needed?
also for '86-'87 the is a service bullitin 07/87 about relocating the rad cap and source for the overflow---these mods hanen't been done to my '86 but...are ther truly needed?
08-18-2002, 10:28 PM
#10
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Originally Posted by 13BAce' date='Aug 18 2002, 11:20 PM
[quote name='fstedy' date='Aug 18 2002, 06:31 PM']i'm not refering to the cap but rather the thermostst itself--the mazda one has a jiggle pin and the generic one doesn't.
also for '86-'87 the is a service bullitin 07/87 about relocating the rad cap and source for the overflow---these mods hanen't been done to my '86 but...are ther truly needed?
also for '86-'87 the is a service bullitin 07/87 about relocating the rad cap and source for the overflow---these mods hanen't been done to my '86 but...are ther truly needed?
so far i'm 3 for 3 on coolant seals. the only engine that didn't have bad ones was the original TII engine that broke a few apex seals